Compositions and Methods for Improving Viral Transduction

Abstract

Disclosed herein is a fusion protein comprising the CR3 domain of low density lipoprotein receptor (LDLR) and a polypeptide having co-behavior. Also provided herein is a polypeptide having co-behavior. In addition, provided herein is a method for improving or reducing the efficiency of viral transduction, comprising the step of administering the fusion protein or the polypeptide having co-behavior described herein.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of U.S. Provisional Application No. 63 / 388,544, filed on Jul. 12, 2022, the entire disclosure of which is incorporated herein by reference.

[0002] Reference to Electronic Sequence Listing The content of the electronic sequence listing (ISOL_010_01WO_SeqList_ST26.xml; size: 54,873 bytes; created on Jul. 11, 2023) is incorporated herein by reference in its entirety.

[0003] The present disclosure generally relates to compositions and methods for improving the efficiency of lentiviral transduction. The present disclosure also provides fusion proteins comprising the CR3 domain of LDLR and a polypeptide having co - behavior, and methods of using them to improve the efficiency of lentiviral transduction. The present disclosure also relates to the use of a polypeptide having co - behavior to improve the efficiency of lentiviral transduction.

Background Art

[0004] Lentiviral transduction is used to genetically engineer therapeutic cells. For example, lentiviral transduction is used to generate T cells such as chimeric antigen receptor (CAR) T cells, which express a chimeric antigen receptor on their surface that targets antigens on tumor cells, resulting in tumor cell death. These therapeutic agents can save lives. However, the transduction efficiency can be low, resulting in high manufacturing costs. There is a need in the art for compositions and methods for improving the efficiency of lentiviral transduction to reduce the cost of CAR T therapeutics. The present disclosure addresses the needs in the art for compositions and methods for improvement.

Summary of the Invention

[0005] Provided herein are compositions comprising a fusion protein comprising the CR3 domain of the low density lipoprotein receptor (LDLR) and a polypeptide having co-behavior. The compositions described herein unexpectedly improve or prevent lentiviral transduction depending on the identity of the polypeptide having co-behavior.

[0006] In this specification, a fusion protein is provided that includes a CR3 domain of low density lipoprotein receptor (LDLR) that is at least 80% identical to the polypeptide of SEQ ID NO: 14, and a polypeptide having co-behavior that is at least 80% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, or 11 - 13. In an embodiment, the CR3 domain of LDLR includes a polypeptide that is at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO: 14. In an embodiment, the CR3 domain of LDLR includes the polypeptide sequence of SEQ ID NO: 14. In an embodiment, the polypeptide having co-behavior includes a polypeptide that is at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, or 11 - 13. In an embodiment, the polypeptide having co-behavior includes the polypeptide sequence of SEQ ID NO: 1. In an embodiment, the polypeptide having co-behavior includes the polypeptide sequence of SEQ ID NO: 2. In an embodiment, the polypeptide having co-behavior includes the polypeptide sequence of SEQ ID NO: 11. In an embodiment, the polypeptide having co-behavior is the N-terminus with respect to the CR3 domain of LDLR (for example, the polypeptide having co-behavior is bound at the N-terminus of the CR3 domain of LDLR). In an embodiment, the polypeptide having co-behavior is the C-terminus with respect to the CR3 domain of LDLR (for example, the polypeptide having co-behavior is bound at the C-terminus of the CR3 domain of LDLR). In an embodiment, the fusion protein includes a linker between the polypeptide having co-behavior and the CR3 domain of LDLR.In an embodiment, the linker has an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 21 to 38.

[0007] Provided herein is a method for improving the efficiency of lentiviral transduction, which includes the steps of transducing cells using a lentivirus and administering to the cells the fusion protein described herein. In an embodiment, the efficiency of lentiviral transduction is improved as compared to the efficiency of a method that does not include the step of administering to the cells transduced using a lentivirus the fusion protein described herein. In an embodiment, the efficiency of lentiviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%.In an embodiment, the method includes administering a fusion protein comprising a polypeptide having a phase behavior with at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to SEQ ID NO: 11. In an embodiment, the method includes administering a fusion protein having the amino acid sequence of SEQ ID NO: 11. In an embodiment, the method includes administering a fusion protein having an amino acid sequence with at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to SEQ ID NO: 5. In an embodiment, the method includes administering a fusion protein having the amino acid sequence of SEQ ID NO: 5. In an embodiment, the method improves the efficiency of lentiviral transduction by at least 120%.

[0008] In an embodiment, a method for improving lentiviral transduction includes transducing cells using a lentivirus and administering to the cells a polypeptide having co-behavior; the amino acid sequence of the polypeptide having co-behavior is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 2. In an embodiment, a method for improving lentiviral transduction includes transducing cells using a lentivirus and administering to the cells a polypeptide having co-behavior; the polypeptide having co-behavior has the amino acid sequence of SEQ ID NO: 2.In an embodiment, the method improves the efficiency of lentiviral transduction by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%. In an embodiment, the method improves the efficiency of lentiviral transduction by at least 90%. In an embodiment, the method includes improving the efficiency of lentiviral transduction as compared to the efficiency of a method that does not include administering a polypeptide having co-behavior to cells transduced with a lentivirus.

[0009] Disclosed herein is a fusion protein comprising a CR3 domain of low density lipoprotein receptor (LDLR) that is at least 80% identical to the polypeptide of SEQ ID NO: 14, and a polypeptide having co-behavior that is at least 80% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, and 41-42. In an embodiment, the CR3 domain of the LDLR in the fusion protein comprises a polypeptide that is at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO: 14. In an embodiment, the CR3 domain of the LDLR comprises the polypeptide sequence of SEQ ID NO: 14. In an embodiment, the polypeptide having co-behavior in the fusion protein comprises a polypeptide that is at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, and 41-42. In an embodiment, the polypeptide having co-behavior in the fusion protein comprises the polypeptide sequence of any one of SEQ ID NO: 1, SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 42. In an embodiment, the fusion protein comprises a linker between the polypeptide having co-behavior and the CR3 domain of the LDLR.In an embodiment, the linker has an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 21 to 38. In an embodiment, the fusion protein has an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO: 5.

[0010] Provided herein is a method for improving the efficiency of lentiviral transduction, the method comprising transducing cells with a lentivirus and administering a fusion protein as described herein, wherein the lentiviral transduction of the cells administered with the lentivirus and the fusion protein is improved as compared to cells transduced with the lentivirus and not administered with the fusion protein. In embodiments, the efficiency of lentiviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%. In embodiments, the efficiency of lentiviral transduction is from about 10% to about 100%, from about 20% to about 100%, from about 30% to about 100%, from about 40% to about 100%, from about 50% to about 100%, from about 60% to about 100%, from about 70% to about 100%, from about 80% to about 100%, from about 90% to about 100%, from about 20% to about 200%, from about 30% to about 200%, from about 40% to about 200%, from about 50% to about 200%, from about 60% to about 200%, from about 70% to about 200%, from about 80% to about 200%, from about 90% to about 200%,From about 100% to about 200%, from about 110% to about 200%, from about 120% to about 200%, from about 130% to about 200%, from about 140% to about 200%, from about 150% to about 200%, from about 160% to about 200%, from about 170% to about 200%, from about 180% to about 200%, from about 190% to about 200%, from about 20% to about 300%, from about 30% to about 300%, from about 40% to about 300%, from about 50% to about 300%, from about 60% to about 300%, from about 70% to about 300%, from about 80% to about 300%, from about 90% to about 300%, from about 100% to about 300%, from about 110% to about 300%, from about 120% to about 300%, from about 130% to about 300%, from about 140% to about 300%, from about 150% to about 300%, from about 160% to about 300%, from about 170% to about 300%, from about 180% to about 300%, from about 190% to about 300%, from about 200% to about 300%, from about 210% to about 300%, from about 220% to about 300%, from about 230% to about 300%, from about 240% to about 300%, from about 250% to about 300%, from about 260% to about 300%, from about 270% to about 300%, from about 280% to about 300%, from about 290% to about 300%, from about 300% to about 300%, from about 20% to about 400%, from about 30% to about 400%, from about 40% to about 400%, from about 50% to about 400%, from about 60% to about 400%, from about 70% to about 400%, from about 80% to about 400%, from about 90% to about 400%, from about 100% to about 400%, from about 110% to about 400%, from about 120% to about 400%, from about 130% to about 400%, from about 140% to about 400%, from about 150% to about 400%, from about 160% to about 400%, from about 170% to about 400%, from about 180% to about 400%, from about 190% to about 400%, from about 200% to about 400%, from about 210% to about 400%, from about 220% to about 400%, from about 230% to about 400%, from about 240% to about 400%, from about 250% to about 400%, from about 260% to about 400%, from about 270% to about 400%, from about 280% to about 400%, from about 290% to about 400%, from about 300% to about 400%, from about 310% to about 400%, from about 320% to about 400%, from about 330% to about 400%, from about 340% to about 400%, from about 350% to about 400%, from about 360% to about 400%, from about 370% to about 400%, from about 380% to about 400%, from about 390% to about 400%, from about 20% to about 500%Improved by about 30% to about 500%, about 40% to about 500%, about 50% to about 500%, about 60% to about 500%, about 70% to about 500%, about 80% to about 500%, about 90% to about 500%, about 100% to about 500%, about 110% to about 500%, about 120% to about 500%, about 130% to about 500%, about 140% to about 500%, about 150% to about 500%, about 160% to about 500%, about 170% to about 500%, about 180% to about 500%, about 190% to about 500%, about 200% to about 500%, about 210% to about 500%, about 220% to about 500%, about 230% to about 500%, about 240% to about 500%, about 250% to about 500%, about 260% to about 500%, about 270% to about 500%, about 280% to about 500%, about 290% to about 500%, about 300% to about 500%, about 310% to about 500%, about 320% to about 500%, about 330% to about 500%, about 340% to about 500%, about 350% to about 500%, about 360% to about 500%, about 370% to about 500%, about 380% to about 500%, about 390% to about 500%, about 400% to about 500%, about 410% to about 500%, about 420% to about 500%, about 430% to about 500%, about 440% to about 500%, about 450% to about 500%, about 460% to about 500%, about 470% to about 500%, about 480% to about 500%, or about 490% to about 500%. Lentiviral transduction of cells administered with lentivirus and a fusion protein is improved compared to cells transduced with lentivirus without administration of the fusion protein.,

[0011] In an embodiment, the method includes administering a fusion protein comprising a polypeptide having a phase behavior with at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to SEQ ID NO: 12 or SEQ ID NO: 42. In an embodiment, the method includes administering a fusion protein comprising a polypeptide having a phase behavior with the amino acid sequence of SEQ ID NO: 12 or SEQ ID NO: 42.

[0012] In an embodiment, the method includes administering a fusion protein comprising the CR3 domain of LDLR having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the polypeptide of SEQ ID NO: 14. In an embodiment, the method includes administering a fusion protein having an amino acid sequence with at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to SEQ ID NO: 5. In an embodiment, the efficiency of lentiviral transduction is improved by at least 120%.

[0013] Provided is a method for improving the efficiency of lentiviral transduction, which includes the steps of transducing cells using a lentivirus and administering a polypeptide having co-behavior; the amino acid sequence of the polypeptide having co-behavior is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 12, and the lentiviral transduction of the cells administered with the lentivirus and the polypeptide having co-behavior is improved as compared to the cells administered with the lentivirus and without the polypeptide having co-behavior. In an embodiment, the efficiency of lentiviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%,Lentiviral transduction of cells administered with a lentivirus and a polypeptide having a co-behavior is improved compared to cells administered with a lentivirus and without a polypeptide having a co-behavior. In embodiments, the efficiency of lentiviral transduction is from about 10% to about 100%, from about 20% to about 100%, from about 30% to about 100%, from about 40% to about 100%, from about 50% to about 100%, from about 60% to about 100%, from about 70% to about 100%, from about 80% to about 100%, from about 90% to about 100%, from about 20% to about 200%, from about 30% to about 200%, from about 40% to about 200%, from about 50% to about 200%, from about 60% to about 200%, from about 70% to about 200%, from about 80% to about 200%, from about 90% to about 200%, from about 100% to about 200%, from about 110% to about 200%, from about 120% to about 200%, from about 130% to about 200%, from about 140% to about 200%, from about 150% to about 200%, from about 160% to about 200%, from about 170% to about 200%, from about 180% to about 200%, from about 190% to about 200%, from about 20% to about 300%, from about 30% to about 300%, from about 40% to about 300%, from about 50% to about 300%, from about 60% to about 300%, from about 70% to about 300%, from about 80% to about 300%, from about 90% to about 300%, from about 100% to about 300%, from about 110% to about 300%, from about 120% to about 300%, from about 130% to about 300%, from about 140% to about 300%, from about 150% to about 300%, from about 160% to about 300%, from about 170% to about 300%, from about 180% to about 300%, from about 190% to about 300%, from about 200% to about 300%, from about 210% to about 300%, from about 220% to about 300%, from about 230% to about 300%, from about 240% to about 300%, from about 250% to about 300%, from about 260% to about 300%, from about 270% to about 300%, from about 280% to about 300%, from about 290% to about 300%, from about 300% to about 300%, from about 20% to about 400%, from about 30% to about 400%, from about 40% to about 400%, from about 50% to about 400%, from about 60% to about 400%, from about 70% to about 400%, from about 80% to about 400%, from about 90% to about 400%, from about 100% to about 400%, from about 110% to about 400%, from about 120% to about 400%, from about 130% to about 400%, from about 140% to about 400%,From about 150% to about 400%, from about 160% to about 400%, from about 170% to about 400%, from about 180% to about 400%, from about 190% to about 400%, from about 200% to about 400%, from about 210% to about 400%, from about 220% to about 400%, from about 230% to about 400%, from about 240% to about 400%, from about 250% to about 400%, from about 260% to about 400%, from about 270% to about 400%, from about 280% to about 400%, from about 290% to about 400%, from about 300% to about 400%, from about 310% to about 400%, from about 320% to about 400%, from about 330% to about 400%, from about 340% to about 400%, from about 350% to about 400%, from about 360% to about 400%, from about 370% to about 400%, from about 380% to about 400%, from about 390% to about 400%, from about 20% to about 500%, from about 30% to about 500%, from about 40% to about 500%, from about 50% to about 500%, from about 60% to about 500%, from about 70% to about 500%, from about 80% to about 500%, from about 90% to about 500%, from about 100% to about 500%, from about 110% to about 500%, from about 120% to about 500%, from about 130% to about 500%, from about 140% to about 500%, from about 150% to about 500%, from about 160% to about 500%, from about 170% to about 500%, from about 180% to about 500%, from about 190% to about 500%, from about 200% to about 500%, from about 210% to about 500%, from about 220% to about 500%, from about 230% to about 500%, from about 240% to about 500%, from about 250% to about 500%, from about 260% to about 500%, from about 270% to about 500%, from about 280% to about 500%, from about 290% to about 500%, from about 300% to about 500%, from about 310% to about 500%, from about 320% to about 500%, from about 330% to about 500%, from about 340% to about 500%, from about 350% to about 500%, from about 360% to about 500%, from about 370% to about 500%, from about 380% to about 500%, from about 390% to about 500%, from about 400% to about 500%, from about 410% to about 500%, from about 420% to about 500%, from about 430% to about 500%, from about 440% to about 500%, from about 450% to about 500%, from about 460% to about 500%, from about 470% to about 500%, from about 480% to about 500%, or from about 490% to about 500% improved, and lentiviral transduction of cells administered with a lentivirus and a polypeptide having a co-behavior is,Cells administered with lentivirus and having a polypeptide with co-behavior are improved compared to cells not administered with the polypeptide.

[0014] In embodiments, the efficiency of lentiviral transduction is improved by at least 90%. In embodiments, the polypeptide having co-behavior has the amino acid sequence of SEQ ID NO: 12.

[0015] These and other embodiments are further described in the following detailed description, examples, and claims.

Brief Description of the Drawings

[0016]

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Mode for Carrying Out the Invention

[0017] Definition As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include the plural unless the context clearly dictates otherwise. Thus, for example, reference to “a protein” can refer to one protein or a mixture of such proteins, and reference to “a method” includes reference to equivalent steps and / or methods known to those of ordinary skill in the art.

[0018] As used herein, the terms “about” or “substantially” when preceding a numerical value indicate a value that plus or minus in the range of 10%. For example, “about 100” includes 90 and 110.

[0019] Also, as used herein, “and / or” refers to and encompasses any and all possible combinations of one or more of the associated listed items, as well as the lack of combinations when interpreted in the alternative (“or”).

[0020] Unless otherwise specified, it is specifically intended that the various features described herein can be used in any combination.

[0021] Furthermore, the present disclosure also contemplates that, in some embodiments, any feature or combination of features described herein can be excluded or omitted. For further illustration, for example, if the present specification indicates that a particular amino acid can be selected from A, G, I, L, and / or V, this language also indicates that the amino acid can be selected from any subset of these amino acids, e.g., A, G, I, or L; A, G, I, or V; A or G; L only; etc., as if each such subcombination were explicitly recited herein. Furthermore, such language also indicates that one or more of the specified amino acids can be waived. For example, in certain embodiments, the amino acid is not A, G, or I; not A; not G or V, as if each such possible waiver were explicitly recited herein.

[0022] As used herein, the term "fragment" when referring to a protein or polypeptide includes truncated forms of the protein or polypeptide. For example, a fragment of LDLR may comprise about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 97%, or about 99% of the amino acids of the full-length LDLR. A fragment of the CR3 domain of LDLR may have about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 97%, or about 99% of the amino acids of the full-length CR3 domain of LDLR. The full-length CR3 domain of LDLR has the amino acid sequence of SEQ ID NO: 14. In embodiments, a fragment of the CR3 domain of LDLR comprises at least 20, at least 21, at least 22, at least 23, at least 24, at least 25, at least 26, at least 27, at least 28, at least 29, at least 30, at least 31, at least 32, at least 33, at least 34, at least 35, at least 36, at least 37, or at least 38 amino acids of the CR3 domain of LDLR.

[0023] As used herein, the terms "peptide", "polypeptide", and "protein" are used interchangeably and refer to a compound composed of amino acid residues covalently linked by peptide bonds. A protein must have at least two amino acids, and there is no limit to the maximum number of amino acids that can make up the sequence of a protein. The term "peptide" may refer to, for example, a short chain of amino acids including natural peptides, recombinant peptides, synthetic peptides, or combinations thereof. Proteins and peptides may include, among others, biologically active fragments, substantially homologous polypeptides, oligopeptides, homodimers, heterodimers, variants of polypeptides, modified polypeptides, derivatives, analogs, and fusion proteins.

[0024] The term "modification" when referring to a polypeptide refers to a mutation, deletion, or addition of one amino acid of the polypeptide. In an embodiment, the polypeptide is the CR3 domain of LDLR. The position of the modification within the CR3 domain of LDLR can be determined based on aligning the polypeptide sequence with SEQ ID NO: 14 (the amino acid sequence of the CR3 domain of LDLR).

[0025] A "polynucleotide" is a sequence of nucleotide bases and may be an RNA, DNA, or DNA-RNA hybrid sequence (including both naturally occurring nucleotides and non-naturally occurring nucleotides). In some embodiments, the polynucleotide is either a single-stranded DNA sequence or a double-stranded DNA sequence.

[0026] For two or more nucleic acid or polypeptide sequences, the term "percent identity" refers to two or more sequences or subsequences that have a specified percentage of nucleotides or amino acid residues that are the same when compared. Unless otherwise specified, percent identity is determined using the EMBL’s European Bioinformatic’s Institute (EMBL-EBI) tool EMBOSS Needle available at https: / / www.ebi.ac.uk / Tools / psa / emboss_needle / . The following default parameters can be used for EMBOSS Needle Pairwise Alignment: Matrix = BLOSUM62; Gap Open = 10; Gap Extension = 0.5; End Gap Penalty = false; End Gap Open = 10; End Gap Extend = 0.5. In embodiments, percent identity is calculated over the full length of the sequences being compared. In some embodiments, sequence identity is calculated over fragments of each of the sequences being compared of about 10 amino acids, about 15 amino acids, about 20 amino acids, about 25 amino acids, about 30 amino acids, about 35 amino acids, about 40 amino acids, about 45 amino acids, about 50 amino acids, about 55 amino acids, about 60 amino acids, about 65 amino acids, about 70 amino acids, about 75 amino acids, about 80 amino acids, about 85 amino acids, about 90 amino acids, about 95 amino acids, about 100 amino acids, about 105 amino acids, about 110 amino acids, about 115 amino acids, about 120 amino acids, about 125 amino acids, about 130 amino acids, about 135 amino acids, about 140 amino acids, about 145 amino acids, about 150 amino acids, about 155 amino acids, about 160 amino acids, about 165 amino acids, about 170 amino acids, about 175 amino acids, about 180 amino acids, about 185 amino acids, about 190 amino acids, about 195 amino acids, or about 200 amino acids.

[0027] A composition comprising a fusion protein comprising a polypeptide having the CR3 domain of LDLR and its relative behavior The present disclosure provides a composition comprising a fusion protein comprising a polypeptide having the CR3 domain of LDLR and co-behavior. In embodiments, the CR3 domain of LDLR is a polypeptide having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO: 14. In embodiments, the CR3 domain of LDLR has contiguous amino acids from about 20 to about 39, about 21 to about 39, about 22 to about 39, about 23 to about 39, about 24 to about 39, about 25 to about 39, about 26 to about 39, about 27 to about 39, about 28 to about 39, about 29 to about 39, about 30 to about 39, about 31 to about 39, about 32 to about 39, about 33 to about 39, about 34 to about 39, about 35 to about 39, about 36 to about 39, about 37 to about 39, or about 38 to about 39 of SEQ ID NO: 14. In embodiments, the CR3 domain of LDLR has contiguous amino acids of about 20, about 21, about 22, about 23, about 24, about 25, about 26, about 27, about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, or about 39 of SEQ ID NO: 14. In embodiments, the CR3 domain of LDLR comprises 1 to 5 modifications, 1 to 4, 1 to 3, or 1 to 2 modifications compared to the polypeptide of SEQ ID NO: 14. In embodiments, the CR3 domain of LDLR comprises 1, 2, 3, 4, or 5 modifications compared to the polypeptide of SEQ ID NO: 14.

[0028] In an embodiment, a polypeptide having phase behavior has at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with a polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, 39, and 41-42. In an embodiment, a polypeptide having phase behavior has 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 modifications as compared to a polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, 39, and 41-42. In an embodiment, a polypeptide having phase behavior includes from about 1 to about 5, from about 1 to about 6, from about 1 to about 7, from about 1 to about 8, from 1 to about 9, or from 1 to about 10 modifications as compared to a polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, 39, and 41-42.

[0029] In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 1. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 2. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 11. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 12. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 13. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 39. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 41. In an embodiment, a polypeptide having phase behavior includes the amino acid sequence of SEQ ID NO: 42.

[0030] In an embodiment, the fusion protein is a polypeptide having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with any one of SEQ ID NOs: 3-5 and 15-20. In an embodiment, the fusion protein is a polypeptide having 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 modifications as compared to the polypeptide of any one of SEQ ID NOs: 3-5 and 15-20. In an embodiment, the fusion protein comprises about 1 to about 5, about 1 to about 6, about 1 to about 7, about 1 to about 8, 1 to about 9, or 1 to about 10 modifications as compared to the polypeptide of any one of SEQ ID NOs: 3-5 and 15-20.

[0031] In an embodiment, the fusion protein comprises the amino acid sequence of SEQ ID NO: 3. In an embodiment, the fusion protein comprises the amino acid sequence of SEQ ID NO: 5.

[0032] In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 1 and the CR3 domain of LDLR (SEQ ID NO: 14). In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 2 and the CR3 domain of LDLR (SEQ ID NO: 14). In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 11 and the CR3 domain of LDLR (SEQ ID NO: 14). In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 12 and the CR3 domain of LDLR (SEQ ID NO: 14). In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 13 and the CR3 domain of LDLR (SEQ ID NO: 14). In an embodiment, the fusion protein comprises a polypeptide having the phase behavior of SEQ ID NO: 42 and the CR3 domain of LDLR (SEQ ID NO: 14).

[0033] In embodiments, nucleic acids encoding the fusion proteins described herein are provided herein. In embodiments, nucleic acids encoding polypeptides having the co-behaviors described herein are provided herein. In embodiments, the polypeptide having co-behaviors is a nucleic acid of any one of SEQ ID NOs: 6-8, or a nucleic acid having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity with any one of SEQ ID NOs: 6-8. In embodiments, the fusion protein is a nucleic acid of any one of SEQ ID NOs: 9-10, or a nucleic acid having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity with any one of SEQ ID NOs: 9-10.

[0034] In embodiments, the fusion protein contains an N-terminal methionine. In embodiments, the fusion protein lacks an N-terminal methionine.

[0035] In embodiments, the fusion protein contains a linker between the polypeptide having co-behaviors and the CR3 domain of LDLR. In embodiments, the linker does not interfere with the function of the fusion proteins described herein. In some embodiments, the linker can take various secondary structures including, but not limited to, α-helix, β-strand, and random coil. In some embodiments, the linker takes an α-helix and contains the amino acid repeat (SEQ ID NO: 21) of (EAAAK) n where n is an integer from 1 to 20.

[0036] In some embodiments, the linker is (G4S) nIt is composed of (SEQ ID NO: 22), where n can be an integer from 1 to 30 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30, etc.). In an embodiment, the polypeptide linker has a repeat of (SGGG)n (SEQ ID NO: 23), where n is an integer from 1 to 50 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50, etc.). In an embodiment, the polypeptide linker has a repeat of (GGGS) n (SEQ ID NO: 24), where n is an integer from 1 to 20 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20, etc.).

[0037] In some embodiments, the linker has the amino acid sequence of KESGSVSSEQLAQFRSLD (SEQ ID NO: 25). In some embodiments, the linker has the amino acid sequence of EGKSSGSGSESKST (SEQ ID NO: 26). In some embodiments, the linker consists of only glycine.

[0038] In some embodiments, the peptide linker contains a protease cleavage site. In some embodiments, the protease cleavage site is a furin cleavage site.

[0039] In some aspects, the polypeptide linker is poly-(Gly) nA linker, where n is an integer from 1 to 30 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30, etc.) (SEQ ID NO: 27). In other embodiments, the linker is selected from the group consisting of dipeptides, tripeptides, and tetrapeptides. In an embodiment, the linker is a dipeptide selected from the group consisting of alanine - serine (AS), leucine - glutamic acid (LE), and serine - arginine (SR).

[0040] In some embodiments, the linker is selected from GKSSGSGSESKS (SEQ ID NO: 28), GSTSGSGKSSEGKG (SEQ ID NO: 29), GSTSGSGKSSEGSGSTKG (SEQ ID NO: 30), GSTSGSGKPGSGEGSTKG (SEQ ID NO: 31), EGKSSGSGSESKEF (SEQ ID NO: 32), SRSSG (SEQ ID NO: 33), and SGSSC (SEQ ID NO: 34).

[0041] In some embodiments, the linker is a self - cleaving peptide. In some embodiments, the self - cleaving peptide is a 2A peptide. The 2A peptide is a class of peptides 18 - 22 amino acids in length that induce ribosome skipping during protein translation in cells. In some embodiments, the 2A peptide is a T2A peptide having the amino acid sequence of EGRGSLLTCGDVEENPGP (SEQ ID NO: 35), a P2A peptide having the amino acid sequence of ATNFSLLKQAGDVEENPGP (SEQ ID NO: 36), an E2A peptide having the amino acid sequence of QCTNYALLKLAGDVESNPGP (SEQ ID NO: 37), or an F2A peptide having the amino acid sequence of VKQTLNFDLLKLAGDVESNPGP (SEQ ID NO: 38). In some embodiments, the 2A peptide has at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% identity with any one of SEQ ID NOs: 35 - 38.

[0042] In an embodiment, a polypeptide having phase behavior is located at the N-terminus with respect to the CR3 domain of LDLR (for example, the polypeptide having phase behavior binds at the N-terminus of the CR3 domain of LDLR). In an embodiment, a polypeptide having phase behavior is located at the C-terminus with respect to the CR3 domain of LDLR (for example, the polypeptide having phase behavior binds at the C-terminus of the CR3 domain of LDLR).

[0043] Method of using a composition comprising a polypeptide having phase behavior or a fusion protein comprising a polypeptide having phase behavior with the CR3 domain of LDLR In embodiments, methods are provided herein for improving the efficiency of lentiviral transduction. In embodiments, the method for improving the efficiency of lentiviral transduction includes administering to a cell the fusion protein described herein. In embodiments, the fusion protein is administered to the cell simultaneously with (i.e., within 15 minutes of) the lentivirus. In embodiments, the fusion protein is administered within 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, or 24 hours of the lentivirus. In embodiments, the fusion protein is administered to the cell before the lentivirus is administered to the cell. In embodiments, the fusion protein is administered to the cell after the lentivirus is administered to the cell. In embodiments, the fusion protein has a sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to any one of SEQ ID NOs: 3-5 or 15-20.

[0044] In an embodiment, a method for improving the efficiency of lentiviral transduction comprises the step of administering to a cell a polypeptide having a phase behavior. In an embodiment, the polypeptide having a phase behavior is administered simultaneously with (i.e., within 15 minutes of) the lentivirus. In an embodiment, the polypeptide having a phase behavior is administered within 15 minutes, within 30 minutes, within 45 minutes, within 1 hour, within 2 hours, within 3 hours, within 4 hours, within 5 hours, within 6 hours, within 7 hours, within 8 hours, within 9 hours, within 10 hours, within 11 hours, within 12 hours, within 13 hours, within 14 hours, within 15 hours, within 16 hours, within 17 hours, within 18 hours, within 19 hours, within 20 hours, within 21 hours, within 22 hours, within 23 hours, or within 24 hours of the lentivirus. In an embodiment, the polypeptide having a phase behavior is administered to the cell before the lentivirus is administered to the cell. In an embodiment, the polypeptide having a phase behavior is administered to the cell after the lentivirus is administered to the cell. In an embodiment, the polypeptide having a phase behavior has a sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to any one of SEQ ID NO: 1, 2, or 11-13.

[0045] In an embodiment, the efficiency of lentiviral transduction (or the proportion of cells infected with lentivirus) is evaluated by flow cytometry. For example, in an embodiment, the lentivirus encodes a fluorescent protein such as green fluorescent protein. The efficiency of lentiviral transduction is the proportion of cells expressing the fluorescent protein. In other embodiments, the lentivirus encodes a cell surface protein. Cells transduced using a lentivirus encoding a cell surface protein can be incubated with a fluorescent antibody that binds to the cell surface protein. The efficiency of lentiviral transduction is the proportion of cells to which the fluorescent antibody binds.

[0046] In an embodiment, the method described herein provides an improved efficiency of lentiviral transduction as compared to alternative methods. In an embodiment, alternative methods include lentiviral transduction methods that do not administer the fusion protein or polypeptide having phase behavior described herein. In an embodiment, alternative methods are conventional methods for improving lentiviral transduction. Examples of conventional methods for improving lentiviral transduction include transduction in the presence of polybrene or the lentiviral enhancer TRANSDUX™ MAX.

[0047] In an embodiment, the method described herein improves the efficiency of lentiviral transduction by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500% compared to an alternative method.

[0048] In an embodiment, a method for improving the efficiency of lentiviral transduction includes administering a polypeptide having a co-behavior with an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 2. In an embodiment, the step of administering a polypeptide having a co-behavior with an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 2 improves the efficiency of lentiviral transduction by at least 90% compared to an alternative method.

[0049] In an embodiment, a method for improving the efficiency of lentiviral transduction includes administering a fusion protein having an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 5. In an embodiment, the step of administering a fusion protein having an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 5 improves the efficiency of lentiviral transduction by at least 120%.

[0050] In an embodiment, the method described herein results in a decrease in the efficiency of lentiviral transduction. In an embodiment, the efficiency of lentiviral transduction of the method for lentiviral transduction described herein, which includes the step of administering to a cell a polypeptide or fusion protein having the co-behavior described herein, is at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500% lower compared to a method that does not administer a polypeptide or fusion protein having the co-behavior described herein. In an embodiment, a method of lentiviral transduction that includes the step of administering a fusion protein having an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 3 decreases the efficiency of lentiviral transduction by at least 80% compared to a method that does not include the step of administering a polypeptide having the co-behavior.

[0051] In embodiments, the methods described herein reduce the efficiency of adenovirus transduction. In embodiments, the efficiency of adenovirus transduction of the methods for adenovirus transduction described herein, which include the step of administering a polypeptide having the phase behavior described herein, is at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500% lower compared to methods that do not administer a polypeptide having the phase behavior. In embodiments, the method includes the step of incubating the cells with the adenovirus and a polypeptide having the phase behavior. In embodiments, the polypeptide having the phase behavior comprises an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 1, 13, 39, and 41.

[0052] Method for stabilizing lentivirus In embodiments, methods for stabilizing lentiviral particles are provided herein. As used herein with respect to lentiviral particles, the terms "stabilizing" or "stabilized" refer to reducing the degradation or aggregation of a sample containing a plurality of lentiviral particles, preventing lentiviral molecules from binding to other proteins, enhancing the synthesis of lentiviral particles by producer cells, or otherwise enhancing the functionality of lentiviral particles by the ability of a fusion protein. In embodiments, lentiviral particles incubated with the fusion proteins described herein are stabilized compared to lentiviral particles not incubated with the fusion proteins described herein in the presence of conditions such as salts, freeze-thaw cycles, about 4-8°C, or about 37°C.

[0053] In embodiments, a method for stabilizing lentivirus includes the step of incubating the lentivirus with a fusion protein described herein. In embodiments, the fusion protein comprises an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to any one of SEQ ID NO: 4 and 5. In embodiments, the fusion protein comprises the CR3 domain of LDLR. In embodiments, the CR3 domain of the LDLR protein comprises an amino acid sequence that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 14. In embodiments, the fusion protein comprises a polypeptide having a phase behavior that is at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to any one of SEQ ID NO: 42 and 2.

[0054] In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of up to about 1.5 M NaCl at room temperature for up to about 1 hour, up to about 2 hours, up to about 3 hours, up to about 4 hours, up to about 5 hours, or up to about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of up to about 1.5 M NaCl at room temperature for at least about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of up to about 1.5 M NaCl at room temperature for from 1 to about 6 hours, from 1 to about 5 hours, from 1 to about 4 hours, from 1 to about 3 hours, or from 1 to about 2 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of up to about 1.5 M NaCl at room temperature for up to about 1 hour, up to about 2 hours, up to about 3 hours, up to about 4 hours, up to about 5 hours, or up to about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of about 1.5 M NaCl at room temperature for at least about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable in the presence of about 1.5 M NaCl at room temperature for from 1 to about 6 hours, from 1 to about 5 hours, from 1 to about 4 hours, from 1 to about 3 hours, or from 1 to about 2 hours.

[0055] In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 4 - 8°C for up to about 1 week, up to about 2 weeks, up to about 3 weeks, up to about 4 weeks, up to about 5 weeks, or up to about 6 weeks. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 4 - 8°C for at least about 1 week, at least about 2 weeks, at least about 3 weeks, at least about 4 weeks, at least about 5 weeks, or at least about 6 weeks. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 4 - 8°C for 1 to about 6 weeks, 1 to about 5 weeks, 1 to about 4 weeks, 1 to about 3 weeks, or 1 to about 2 weeks.

[0056] In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 37°C for up to about 1 hour, up to about 2 hours, up to about 3 hours, up to about 4 hours, up to about 5 hours, or up to about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 37°C for at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, at least about 5 hours, or at least about 6 hours. In embodiments, when the lentivirus is incubated with the fusion protein described herein, the lentivirus is stable at about 37°C for 1 to about 6 hours, 1 to about 5 hours, 1 to about 4 hours, 1 to about 3 hours, or 1 to about 2 hours.

[0057] In embodiments, when a lentivirus is incubated with the fusion proteins described herein, the lentivirus is stable through multiple freeze-thaw cycles. In embodiments, when a lentivirus is incubated with the fusion proteins described herein, the lentivirus is stable during at least 1 freeze-thaw cycle, at least about 2 freeze-thaw cycles, at least about 3 freeze-thaw cycles, at least about 4 freeze-thaw cycles, at least about 5 freeze-thaw cycles, at least about 6 freeze-thaw cycles, at least about 7 freeze-thaw cycles, at least about 8 freeze-thaw cycles, at least about 9 freeze-thaw cycles, or at least about 10 freeze-thaw cycles. In embodiments, when a lentivirus is incubated with the fusion proteins described herein, the lentivirus is stable during from 1 to about 10 freeze-thaw cycles, from 1 to about 9 freeze-thaw cycles, from 1 to about 8 freeze-thaw cycles, from 1 to about 7 freeze-thaw cycles, from 1 to about 6 freeze-thaw cycles, from 1 to about 5 freeze-thaw cycles, from 1 to about 4 freeze-thaw cycles, from 1 to about 3 freeze-thaw cycles, or from 1 to about 2 freeze-thaw cycles.

[0058] Sequence In embodiments, the polypeptides or nucleic acids of Table A are provided herein. In embodiments, polypeptides or nucleic acids having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the polypeptides or nucleic acids of Table A are provided herein.

[0059] [Table 1] TIFF2025522745000003.tif240170TIFF2025522745000004.tif226170TIFF2025522745000005.tif237170TIFF2025522745000006.tif136170 [Examples]

[0060] Example 1: The polypeptide and / or fusion protein having the phase behavior described in this specification inhibits or enhances lentiviral transduction. Objective: To evaluate the ability of a polypeptide having phase behavior or a fusion protein (reagents 1 to 5 in Table B) containing a polypeptide having phase behavior and the CR3 domain of the low-density lipoprotein receptor (LDLR) to affect lentiviral transduction. Each fusion protein of SEQ ID NOs: 3 to 5 contained a different polypeptide having phase behavior.

[0061] [Table 2] Method - Cell culture: HEK293T cells were seeded in 24-well plates. 500 μL of cells were suspended in complete medium (Dulbecco's Modified Eagle's Medium (DMEM, GIBCO® catalog No. A4192001) supplemented with 10% fetal bovine serum (FBS GIBCO® catalog No. 10082147) and 1x non-essential amino acids (NEAA GIBCO® catalog No. 11140050)). 50,000 cells were added to each well. The plates were incubated overnight in an incubator at 37°C and 5% CO2.

[0062] Method - Lentiviral transduction: The next morning, the cell medium was replaced with 500 μL of fresh medium. 5 μL of a lentivirus encoding green fluorescent protein (GFP) (4×10 6 vg / mL) was added to each well. Reagent 1, 2, 3, 4, or 5 was added to each well (1 μM). HEK293T cells transduced with lentivirus without incubation with reagent 1, 2, 3, 4, or 5 were used as a control. The lentivirus was incubated with the cells for 24 hours. p24 ELISA was evaluated to determine the virus load. Flow cytometry was performed to identify the amount of GFP-expressing cells.

[0063] Results: Figure 1 shows the percentage of cells expressing GFP compared to the control. Reagents 1 and 4 had no effect on the transduction efficiency. Reagents 2 and 5 significantly enhanced the lentiviral transduction efficiency. In contrast, Reagent 3 significantly blocked the lentiviral transduction efficiency. Notably, Reagents 3 and 5 contained different polypeptides with opposite behaviors. Reagent 3 contained a polypeptide with the opposite behavior of SEQ ID NO: 1, and Reagent 5 contained a polypeptide with the opposite behavior of SEQ ID NO: 11. This data unexpectedly shows that polypeptides with opposite behaviors have different effects on lentiviral transduction. The viral load in the supernatant of each sample remained unchanged (Figure 2). This indicates that the virus was retained in the supernatant without being damaged.

Example

[0064] Example 2: The fusion proteins described herein stabilize lentivirus under various conditions Objective: To evaluate the ability of the polypeptides with opposite behaviors in Example 1 (Reagents 4 and 5 in Table B) to stabilize lentivirus under various conditions before transduction. Each protein of SEQ ID NOs: 4 and 5 contained different polypeptides with opposite behaviors.

[0065] Method - Cell culture: HEK293T cells were seeded in 24-well plates. 500 μL of cells were suspended in complete medium (Dulbecco’s Modified Eagle’s Medium (DMEM, GIBCO™ Catalog No. A4192001) supplemented with 10% fetal bovine serum (FBS GIBCO™ Catalog No. 10082147) and 1x non-essential amino acids (NEAA GIBCO™ Catalog No. 11140050)). 50,000 cells were added to each well. The plates were incubated overnight in an incubator at 37°C and 5% CO2.

[0066] Method - Lentivirus Generation: Lentiviruses were generated using adherent cells in medium containing serum or suspension cells in serum-free medium.

[0067] Method - Lentiviral Transduction: The next morning, the cell medium was replaced with 500 μL of fresh medium. 5 μL of lentivirus encoding green fluorescent protein (GFP) (4×10 6 vg / mL) was incubated with reagent 4 or 5 (10 μM). Then, the composition containing the lentivirus and reagent 4 or 5 was added to each well. HEK293T cells transduced with lentivirus without incubation with reagent 4 or 5 were used as a control. The lentivirus was incubated with the cells for 24 hours. Flow cytometry was performed to determine the amount of cells expressing GFP.

[0068] Method - Stabilization at Various Temperatures: Aliquots containing reagent 4 or 5 mixed with lentivirus were stored under the following conditions: (1) stored at 4 - 8 °C for 2 months, and additional samples were taken weekly for testing; (2) stored at 37 °C for 6 hours, and additional samples were taken every hour for testing; or (3) stored at -80 °C for 1 hour, then thawed on ice (one freeze-thaw cycle), and the freeze-thaw cycle was repeated for a total of 5 cycles, and additional samples were taken after each freeze-thaw cycle for testing. Samples taken at various time points were transduced as described above.

[0069] Method - Stabilization at High Salt Concentrations:: Aliquots containing reagent 4 or 5 mixed with lentivirus were stored, rotated with 1.5 M NaCl at room temperature for 12 hours, and additional samples were taken every hour for testing. Samples taken at various time points were transduced with lentivirus as described above.

[0070] Results: Figures 3A and 3B show the stability of lentiviral particles in 1.5 M NaCl from 0 to 12 hours, as measured by percent GFP+ cells. Figure 3A shows the stability of lentivirus produced in adherent cells in the presence of serum and reagent 5, compared to the control. Figure 3B shows the stability of lentivirus produced in suspension cells in the absence of serum and in the presence of reagent 4 or 5, compared to the control. The CR3 domain of LDLR resulted in enhanced statistically significant stability up to 6 hours for both lentiviruses produced using adherent and suspension cells, compared to the control.

[0071] Figures 4A and 4B show the stability of lentiviral particles at 4 - 8 °C for two months, as measured by percent GFP+ cells. Figure 4A shows the stability of lentivirus produced in adherent cells in the presence of serum and reagent 4 or 5, compared to the control. Figure 4B shows the stability of lentivirus produced in suspension cells in the absence of serum and in the presence of reagent 4 or 5, compared to the control. The CR3 domain of LDLR resulted in enhanced stability up to 5 weeks for both adherent and suspension conditions, compared to the control.

[0072] Figures 5A and 5B show the stability of lentiviral particles at 37 °C for 6 hours, as measured by percent GFP+ cells. Figure 5A shows the stability of lentivirus produced in adherent cells in the presence of serum and reagent 5, compared to the control. Figure 5B shows the stability of lentivirus produced in suspension cells in the absence of serum and in the presence of reagent 4 or 5, compared to the control. The CR3 domain of LDLR resulted in enhanced statistically significant stability up to 6 hours for both adherent and suspension conditions, compared to the control.

[0073] Figure 6 shows the stability of lentiviral particles in five freeze - thaw cycles at - 80°C, measured by percent GFP+ cells, in serum - free suspension conditions for lentivirus production with reagent 4 or 5, compared to the control. The CR3 domain of LDLR resulted in enhanced statistically significant stability up to five freeze - thaw cycles compared to the control.

[0074] These results indicate that the addition of reagent 4 and / or 5 stabilizes lentiviruses exposed to various temperatures (4 - 8°C, 37°C, and - 80°C) and salt conditions (1.5 M NaCl), thus maintaining the effectiveness of the lentiviruses.

Example

[0075] Example 3: Polypeptides having the phase behavior described herein inhibit adenovirus transduction Objective: To evaluate the ability of polypeptides having phase behavior (reagents 1 and 2 in Table C) to affect adenovirus transduction.

[0076]

Table 3

[0077] Method - Adenovirus transduction: The next morning, the cell medium was replaced with 500 μL of fresh medium. 1 μL of an adenovirus encoding green fluorescent protein (GFP) (1x10 12(vg / mL) was added to each well. Reagent 1 or 2 was added to each well (0.1 μM, 1 μM, 10 μM, 100 μM). HEK293T cells transfected with adenovirus without incubation with Reagent 1 or 2 were used as a control. The adenovirus was incubated with the cells for 24 hours. Infectivity was verified using the INVITROGEN™ EVOS™ M5000 Live Cell Imager. Flow cytometry was performed to identify the amount of cells expressing GFP.

[0078] Results: Figures 7A and 7B show the percentage of cells expressing GFP compared to the control for Reagents 1 and 2, respectively. Both Reagents 1 and 2 blocked adenovirus transfection at concentrations above 1 μM (not determined at higher concentrations).

[0079] Numbered embodiments of the present disclosure Notwithstanding the appended claims, the present disclosure describes the following numbered embodiments.

[0080] 1. A fusion protein comprising a CR3 domain of low density lipoprotein receptor (LDLR) that is at least 80% identical to the polypeptide of SEQ ID NO: 14, and a polypeptide having co-behavior that is at least 80% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, or 11 - 13.

[0081] 2. The fusion protein of embodiment 1, wherein the CR3 domain of LDLR comprises a polypeptide that is at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO: 14.

[0082] 3. The fusion protein of embodiment 2, wherein the CR3 domain of LDLR comprises the polypeptide sequence of SEQ ID NO: 14.

[0083] 4. The polypeptide having phase behavior is a fusion protein of any one of Embodiments 1 to 3, including a polypeptide having at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with the polypeptide of any one of SEQ ID NO: 1, 2, or 11-13.

[0084] 4. The polypeptide having phase behavior is a fusion protein of any one of Embodiments 1 to 3, including the polypeptide sequence of SEQ ID NO: 1.

[0085] 5. The polypeptide having phase behavior is a fusion protein of any one of Embodiments 1 to 3, including the polypeptide sequence of SEQ ID NO: 2.

[0086] 6. The polypeptide having behavior is a fusion protein of any one of Embodiments 1 to 3, including the polypeptide sequence of SEQ ID NO: 11.

[0087] 7. The polypeptide having phase behavior is the N-terminus with respect to the CR3 domain of LDLR, and is a fusion protein of any one of Embodiments 1 to 6.

[0088] 8. The polypeptide having phase behavior is the C-terminus with respect to the CR3 domain of LDLR, and is a fusion protein of any one of Embodiments 1 to 6.

[0089] 9. A fusion protein of any one of Embodiments 1 to 6, including a linker between the polypeptide having phase behavior and the CR3 domain of LDLR.

[0090] 10. The linker is a fusion protein of Embodiment 9 having an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 21 to 38.

[0091] 11. A method for improving the efficiency of lentiviral transduction, comprising the steps of transducing cells with a lentivirus and administering a fusion protein of any one of Embodiments 1 to 10.

[0092] 12. The method of Embodiment 11, wherein the efficiency of lentiviral transduction is improved as compared to the efficiency of a method that does not include the step of administering a fusion protein of any one of Embodiments 1 to 10.

[0093] 13. The method of Embodiment 11, wherein the efficiency of lentiviral transduction is improved as compared to a conventional method for improving lentiviral transduction.

[0094] 14. The method of any one of Embodiments 11-13, wherein the efficiency of lentiviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%.

[0095] 15. The method of any one of Embodiments 11-14, wherein the fusion protein comprises a polypeptide having a phase behavior having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO: 11.

[0096] 16. The method of Embodiment 15, wherein the fusion protein comprises a polypeptide having a phase behavior having the amino acid sequence of SEQ ID NO: 11.

[0097] 17. The method according to any one of embodiments 11 to 16, wherein the fusion protein has an amino acid sequence having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO: 5.

[0098] 18. The method according to embodiment 17, wherein the fusion protein has the amino acid sequence of SEQ ID NO: 5.

[0099] 19. The method according to any one of embodiments 14 to 18, wherein the efficiency of lentiviral transduction is improved by at least 120%.

[0100] 20. A method for improving the efficiency of lentiviral transduction, comprising the steps of transducing cells with a lentivirus and administering a polypeptide having a co-behavior, wherein the amino acid sequence of the polypeptide having a co-behavior is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 2.

[0101] 21. The method according to embodiment 20, wherein the polypeptide having a co-behavior has the amino acid sequence of SEQ ID NO: 2.

[0102] 22. The method of Embodiment 20 or 21, wherein the efficiency of viral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%.

[0103] 23. The method of any one of Embodiments 20 to 22, wherein the efficiency of lentiviral transduction is improved by at least 90%.

[0104] 24. The method of any one of Embodiments 20 to 23, wherein the efficiency of lentiviral transduction is improved as compared to the efficiency of viral transduction of a method that does not include the step of administering a polypeptide having a phase behavior.

[0105] 25. The method of any one of Embodiments 20 to 23, wherein the efficiency of lentiviral transduction is improved as compared to a conventional method for improving lentiviral transduction.

[0106] Incorporation by reference All references, articles, publications, patents, patent publications, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes. However, no reference, article, publication, patent, patent publication, or patent application cited herein is to be construed as an admission or suggestion that it constitutes valid prior art or forms part of the common general knowledge in any country in the world, nor should it be so construed. The following references are hereby incorporated by reference in their entirety herein: U.S. Patent No. 11,015,174 and U.S. Patent Publication No. 2019 / 0055523.

Claims

1. A fusion protein comprising a CR3 domain of low density lipoprotein receptor (LDLR) that is at least 80% identical to the polypeptide of SEQ ID NO: 14, and a polypeptide having co-behavior that is at least 80% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, and 41-42.

2. The fusion protein according to claim 1, wherein the CR3 domain of the LDLR comprises a polypeptide that is at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO:

14.

3. The fusion protein according to claim 2, wherein the CR3 domain of the LDLR comprises the polypeptide sequence of SEQ ID NO:

14.

4. The fusion protein according to any one of claims 1 to 3, wherein the polypeptide having co-behavior comprises a polypeptide that is at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 1, 2, 11-13, and 41-42.

5. The fusion protein according to any one of claims 1 to 4, wherein the polypeptide having co-behavior comprises the polypeptide sequence of any one of SEQ ID NO: 1, SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO:

42.

6. The fusion protein according to any one of claims 1 to 5, comprising a linker between the polypeptide having co-behavior and the CR3 domain of the LDLR.

7. The linker of the fusion protein according to claim 6 has an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of any one of SEQ ID NOs: 21 to 38.

8. The fusion protein according to any one of claims 1 to 7 has an amino acid sequence that is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the polypeptide of SEQ ID NO:

5.

9. A method for improving the efficiency of lentiviral transduction, comprising the steps of transducing cells using a lentivirus and administering the fusion protein according to any one of claims 1 to 8, wherein the lentiviral transduction of the cells administered with the lentivirus and the fusion protein is improved as compared to cells transduced using the lentivirus without administering the fusion protein.

10. The method according to claim 9, wherein the efficiency of retroviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%.

11. The method according to claim 9 or 10, wherein the fusion protein comprises a polypeptide having a co-behavior having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO: 12 or SEQ ID NO:

42.

12. The method according to claim 11, wherein the fusion protein comprises a polypeptide having a co-behavior having the amino acid sequence of SEQ ID NO: 12 or SEQ ID NO:

42.

13. The method according to any one of claims 9 to 12, wherein the CR3 domain of the LDLR is a polypeptide having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO:

14.

14. The method according to any one of claims 9 to 13, wherein the CR3 domain of the LDLR is the polypeptide of SEQ ID NO:

14.

15. The method according to any one of claims 9 to 14, wherein the fusion protein has an amino acid sequence having at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity with SEQ ID NO:

5.

16. The method according to any one of claims 9 to 15, wherein the efficiency of the lentiviral transduction is improved by at least 120%.

17. A method for improving the efficiency of lentiviral transduction, comprising the steps of transducing cells with a lentivirus and administering a polypeptide having a co-behavior, wherein the amino acid sequence of the polypeptide having the co-behavior is at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 12, and the lentiviral transduction of the cells administered with the lentivirus and the polypeptide having the co-behavior is improved as compared to cells administered with the lentivirus but not with the polypeptide having the co-behavior. **Claim 18** The method according to claim 17, wherein the efficiency of lentiviral transduction is improved by at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, at least 200%, at least 210%, at least 220%, at least 230%, at least 240%, at least 250%, at least 260%, at least 270%, at least 280%, at least 290%, at least 300%, at least 310%, at least 320%, at least 330%, at least 340%, at least 350%, at least 360%, at least 370%, at least 380%, at least 390%, at least 400%, at least 410%, at least 420%, at least 430%, at least 440%, at least 450%, at least 460%, at least 470%, at least 480%, at least 490%, or at least 500%.

19. The method according to claim 17 or 18, wherein the efficiency of lentiviral transduction is improved by at least 90%.

20. The method according to any one of claims 17 to 19, wherein the polypeptide having the phase behavior has the amino acid sequence of SEQ ID NO: 12.

Images