Targeting b cell activating factor receptor (BAFF-r) using ligand-based chimeric antigen receptor (CAR)-t cells

Abstract

To provide ligand-based chimeric antigen receptor (CAR) cells.SOLUTION: The disclosure provides immune cells expressing a chimeric antigen receptor that recognizes a receptor of B-cell activating factor (BAFF). The immune cells are selected from cytotoxic T lymphocytes, natural killer cells or natural killer T cells. The chimeric antigen receptor recognizes the receptor of B-cell activating factor (BAFF) selected from the group consisting of variants comprising specific sequences. The disclosure further provides methods of treating a variety of conditions, such as cancers and autoimmune diseases, using the immune cells.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001]

[0001] Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 980,727, filed February 24, 2020, and U.S. Provisional Patent Application No. 62 / 908,795, filed October 1, 2019, all of which are hereby incorporated by reference in their entireties.

[0002]

[0003] Sequence Listing Reference The sequence listing in this patent document is provided as a text file entitled "60147-SEQ-LIST_ST25.txt," created on May 29, 2020, and is 46 kB in size. The contents of this file are incorporated herein by reference in their entirety.

[0003]

[0004] The present disclosure generally relates to chimeric antigen receptor (CAR) cells that recognize a receptor for B-cell activating factor (BAFF) on the surface of cells. More specifically, the present disclosure relates to cytotoxic T lymphocytes, natural killer (NK) cells, or natural killer T (NKT) cells that express a chimeric receptor that recognizes a receptor for BAFF. The present disclosure further relates to methods of using the disclosed CAR cells to treat various conditions, such as cancer and autoimmune diseases. [Background technology]

[0004]

[0005] Some cancers are currently incurable. For other cancers, chemotherapy is only partially effective, with a significant proportion of patients experiencing relapse following treatment. Some vascular tumors can be treated with hematopoietic stem cell transplantation (HSCT), but fewer than 30% of patients requiring HSCT have a matched donor of the required age. In another example, approximately 20% of patients with acute lymphoblastic leukemia (ALL), the most common childhood cancer in the United States, with more than 3,000 children diagnosed each year, develop resistance to conventional chemotherapeutic approaches. Thus, there is an urgent need to develop new therapeutic pathways to treat patients across a wide range of conditions.

[0005]

[0006] B-cell-activating factor (BAFF) is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. BAFF signaling is essential for the generation of mature B cells and supports the survival of normal and malignant B cells. BAFF has at least three known receptors: B-cell maturation antigen transmembrane activator (BCMA), TAML interactor (TACI), and BAFF receptor (BAFF-R). BAFF-R is specific for BAFF, whereas BCMA and TACI share another homologous ligand, APRIL. Recent studies have demonstrated that BAFF-R is expressed on the surface of ALL cells, making BAFF inhibition a potential target for treating ALL and other conditions in which BAFF is implicated. Summary of the Invention

[0006]

[0007] According to the present disclosure, in a first aspect, there is a method of treating a patient in need thereof, comprising administering a composition comprising cytotoxic T lymphocytes, natural killer (NK) cells, or natural killer T (NKT) cells. The cytotoxic T lymphocytes, NK cells, or NKT cells express a chimeric receptor that recognizes a receptor for B cell activating factor (BAFF). Furthermore, the chimeric receptor may be a chimeric receptor having a sequence similar to SEQ ID NO: 1 or a partial sequence thereof, or a BAF receptor having 95% or greater sequence identity to SEQ ID NO: 1 or a partial sequence thereof. Includes ent.

[0007]

[0008] In an example of the first embodiment, the partial sequence comprises SEQ ID NO:2 or a variant having 95% or greater sequence homology to SEQ ID NO:2.

[0009] In another embodiment of the first aspect, the partial sequence comprises SEQ ID NO:3 or a variant having 95% or greater sequence identity to SEQ ID NO:3.

[0008]

[0010] In yet another example of the first embodiment, the chimeric receptor further comprises one or more hinge domains.

[0011] In another example of the first embodiment, the hinge domain is selected from the group consisting of a hinge domain of CD8α having SEQ ID NO: 4 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 4 and a hinge domain of IgG1 having SEQ ID NO: 5 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 5.

[0009]

[0012] In another example of the first embodiment, the chimeric receptor further comprises one or more transmembrane domains.

[0013] In another example of the first embodiment, the transmembrane domain is selected from the group consisting of a transmembrane domain of CD8α having SEQ ID NO: 6 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 6 and a transmembrane domain of CD28 having SEQ ID NO: 7 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 7.

[0010]

[0014] In yet another example of the first aspect, the chimeric receptor further comprises one or more intracellular domains.

[0015] In another example of the first embodiment, the intracellular domain is selected from the group consisting of the intracellular domain of 41BB having SEQ ID NO:8 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:8, the intracellular domain of CD28 having SEQ ID NO:9 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:9, the intracellular domain of CD3-zeta having SEQ ID NO:10 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:10, and the intracellular domain of OX40 having SEQ ID NO:11 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:11.

[0011]

[0016] In yet another example of the first embodiment, the chimeric receptor further comprises a hinge domain, a transmembrane domain and one or more intracellular domains.

[0017] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:15 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:15.

[0012]

[0018] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:16 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:16.

[0019] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:17 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:17.

[0013]

[0020] In yet another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:18 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:18.

[0021] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:19 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:19.

[0014]

[0022] In another example of the first embodiment, the chimeric receptor is SEQ ID NO: 20 or SEQ ID NO: 20 Includes variants thereof with 95% or greater sequence homology.

[0023] In another example of the first embodiment, the chimeric receptor further comprises a signaling peptide.

[0015]

[0024] In one example of the first embodiment, the signaling peptide comprises SEQ ID NO:13 or SEQ ID NO:14, or a variant thereof having 95% or greater sequence homology to SEQ ID NO:13 or SEQ ID NO:14.

[0016]

[0025] In yet another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:21 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:21.

[0026] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:22 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:22.

[0017]

[0027] In another example of the first embodiment, the chimeric receptor comprises SEQ ID NO:23 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:23.

[0028] In yet another example of the first embodiment, the T lymphocytes, NK cells or NKT cells are isolated from a human.

[0018]

[0029] In another example of the first embodiment, the T lymphocytes, NK cells or NKTs are autologous.

[0030] In another example of the first embodiment, the T lymphocytes, NK cells or NKTs are allogeneic.

[0019]

[0031] In yet another example of the first aspect, the receptor for BAFF is selected from the group consisting of B-cell maturation antigen transmembrane activator (BCMA), TAML interactor (TACI) and BAFF receptor (BAFF-R).

[0020]

[0032] In another example of the first aspect, a patient in need thereof has been diagnosed with an autoimmune disorder.

[0033] In another example of the first aspect, the autoimmune disorder exhibits autoimmune B cells.

[0021]

[0034] In yet another example of the first aspect, the autoimmune disorder is selected from systemic lupus erythematosus, Sjogren's syndrome, narcolepsy, diabetes, pancreatitis, Crohn's disease, celiac disease, ankylosing spondylitis, psoriasis, Graves' disease, and rheumatoid arthritis.

[0022]

[0035] In another example of the first aspect, a patient in need thereof has been diagnosed with cancer.

[0036] In another example of the first aspect, the cancer is a hematological malignancy.

[0037] In yet another example of the first aspect, the malignant hematological disease is selected from the group consisting of acute lymphocytic leukemia, acute myeloid leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, hairy cell leukemia, diffuse large B-cell lymphoma, mantle cell lymphoma, follicular lymphoma, marginal zone lymphoma, acute lymphoblastic leukemia, non-Hodgkin's lymphoma, Hodgkin's lymphoma, B-cell malignancies, and multiple myeloma.

[0023]

[0038] In another example of the first aspect, the composition is co-administered with one or more chemotherapeutic agents.

[0039] In a second embodiment, there is a cytotoxic T lymphocyte, natural killer (NK) cell, or natural killer T (NKT) cell expressing a chimeric receptor that recognizes the receptor for B-cell activating factor (BAFF) and comprises SEQ ID NO: 1 or a partial sequence thereof, or a variant having 95% or greater sequence identity to SEQ ID NO: 1 or a partial sequence thereof.

[0024]

[0040] In an example of the second embodiment, the partial sequence comprises SEQ ID NO:2 or a variant having 95% or greater sequence homology to SEQ ID NO:2.

[0041] In another example of the second embodiment, the partial sequence comprises SEQ ID NO:3 or a variant having 95% or greater sequence homology to SEQ ID NO:3.

[0025]

[0042] In another example of the second embodiment, the chimeric receptor further comprises one or more hinge domains.

[0043] In another example of the second embodiment, the hinge domain is selected from the group consisting of a hinge domain of CD8α having SEQ ID NO: 4 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 4 and a hinge domain of IgG1 having SEQ ID NO: 5 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 5.

[0026]

[0044] In yet another example of the second embodiment, the chimeric receptor further comprises one or more transmembrane domains.

[0045] In another example of the second embodiment, the transmembrane domain is selected from the group consisting of a transmembrane domain of CD8α having SEQ ID NO: 6 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 6 and a transmembrane domain of CD28 having SEQ ID NO: 7 or a variant thereof having 95% or greater sequence identity to SEQ ID NO: 7.

[0027]

[0046] In another example of the second embodiment, the chimeric receptor further comprises one or more intracellular domains.

[0047] In another example of the second embodiment, the intracellular domain is selected from the group consisting of the intracellular domain of 41BB having SEQ ID NO:8 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:8, the intracellular domain of CD28 having SEQ ID NO:9 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:9, the intracellular domain of CD3-zeta having SEQ ID NO:10 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:10, and the intracellular domain of OX40 having SEQ ID NO:11 or a variant thereof having 95% or greater sequence identity to SEQ ID NO:11.

[0028]

[0048] In yet another example of the second embodiment, the chimeric receptor further comprises a hinge domain, a transmembrane domain and one or more intracellular domains.

[0049] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:15 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:15.

[0029]

[0050] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:16 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:16.

[0051] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:17 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:17.

[0030]

[0052] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:18 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:18.

[0053] In yet another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:19 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:19.

[0031]

[0054] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:20 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:20.

[0055] In another example of the second embodiment, the chimeric receptor further comprises a signaling peptide. In one example, the signaling peptide comprises SEQ ID NO:13 or SEQ ID NO:14, or a variant thereof having 95% or greater sequence homology to SEQ ID NO:13 or SEQ ID NO:14.

[0032]

[0056] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:21 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:21.

[0057] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:22 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:22.

[0033]

[0058] In another example of the second embodiment, the chimeric receptor comprises SEQ ID NO:23 or a variant thereof having 95% or greater sequence homology to SEQ ID NO:23.

[0059] In yet another example of the second embodiment, the T lymphocytes, NK cells or NKT cells are isolated from a human.

[0034]

[0060] In another example of the second embodiment, the T lymphocytes, NK cells or NKTs are autologous.

[0061] In another example of the second embodiment, the T lymphocytes, NK cells or NKTs are allogeneic.

[0035]

[0062] In yet another example of the second embodiment, the receptor for BAFF is selected from the group consisting of B-cell maturation antigen transmembrane activator (BCMA), TAML interactor (TACI) and BAFF receptor (BAFF-R).

[0036]

[0063] In yet another example of the second aspect, a method of treating cancer comprises administering to a patient in need thereof a composition comprising cytotoxic T lymphocytes, NK cells or NKT cells according to the second aspect.

[0037]

[0064] In another example of the second aspect, a method of treating an autoimmune disease comprises administering to a patient in need thereof a composition comprising cytotoxic T lymphocytes, NK cells or NKT cells according to the second aspect.

[0038]

[0065] Additional features and advantages will be set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from that description, or will be learned by practicing the embodiments described herein, including the detailed description that follows, the claims, and the accompanying drawings.

[0039]

[0066] It is to be understood that both the foregoing general description and the following detailed description are merely illustrative and are intended to provide a summary or framework for understanding the nature and characteristics of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate one or more embodiments and, together with the description, serve to explain the principles and operation of the various embodiments. As used herein, directional terms, such as up, down, right, left, front, back, top, and bottom, are used only in relation to the depicted figures and are not intended to imply absolute orientations. [Brief explanation of the drawings]

[0040]

[0067] The above and other features, examples, and advantages of aspects or examples of the present disclosure will be better understood from the following detailed description when read in conjunction with the accompanying drawings. [Figure 1]

[0068] FIG. 1 is an exemplary schematic diagram of a CAR construct according to the present disclosure. [Figure 2]

[0069] FIG. 2 is a schematic diagram of exemplary CAR constructs SEQ ID NOs: 15-17 and 21-23 according to the present disclosure. [Figure 3]

[0070] FIG. 3 contains a graph showing increased expression of BAFF-R on the surface of ALL cells. [Figure 4]

[0071] FIG. 4 shows flow cytometry histograms of BAFF-R expression in newly diagnosed, relapsed ALL patients. [Figure 5]

[0072] Figure 5 shows the killing activity of BAFF-CAR-T expressing SEQ ID NO: 15 and SEQ ID NO: 17 in MCL cells. [Figure 6]

[0073] Figure 6 is a series of graphs showing cytotoxicity against leukemia cell lines by BAFF-CAR-T cells. [Figure 7]

[0074] Figure 7 is a scatter plot showing increased degranulation of CAR-T cells following incubation with Jeko-1 cells. [Figure 8]

[0075] Figure 8 is a graph showing tumor burden following treatment with BAFF-CAR-T cells. [Figure 9]

[0076] Figure 9 shows photographs of mice engrafted with a human leukemia cell line following treatment with a PBS control (left) and BAFF-CAR-T cells (right) according to the present disclosure. [Figure 10]

[0077] Figure 10 is a line graph showing survival following treatment with control and BAFF-CAR-T cells according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0041]

[0078] Example embodiments will now be described more fully hereinafter with reference to the accompanying figures, in which example embodiments and representative data are shown. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts. However, embodiments may take many different forms and should not be construed as limited to the embodiments specifically set forth herein. These example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the claims to those skilled in the art.

[0042]

[0079] Directional terms used herein (e.g., up, down, right, left, front, back, above, below) are used only in relation to the depicted figures and are not intended to imply absolute orientation.

[0043]

[0080] As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other contents and characteristics are not necessarily exact, but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding, measurement error, and the like, as well as other factors known to those skilled in the art. When the term "about" is used to describe a value or an endpoint of a range, it should be understood that the disclosure includes the specific value or endpoint referred to. Whether or not a numerical value or range endpoint is stated as "about" in the specification, the numerical value or range endpoint is intended to include two embodiments, one modified by "about" and one not. It will be further understood that each endpoint of a range is significant both with respect to the other endpoint and independently of the other endpoint.

[0044]

[0081] As used herein, the terms "substantial," "substantially," and variations thereof are intended to refer to a described feature being equal or approximately equal to a value or description. For example, a "substantially planar" surface is intended to indicate a surface that is flat or nearly flat. Furthermore, "substantially" is intended to indicate that two values ​​are equal or approximately equal. In some embodiments, "substantially" can refer to values ​​that are within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.

[0045]

[0082] The terms "substantially" and "about" are used to describe any quantitative comparison, value, measurement, or other representation. It is noted that the terms "free" or "substantially free" may be used herein to express the inherent degree of uncertainty that can be attributed to a given quantity. These terms are also used herein to express the extent to which a quantitative expression may differ from a stated reference without changing the basic function of the subject matter in question. Thus, for example, cells that are "free" or "substantially free" of T cell contamination are cells to which T cells have not been actively added or batched into cell culture, but which may be present in negligible amounts as a contaminant resulting from natural cell progression during expansion. Similarly, other components may be similarly characterized as "free" or "substantially free."

[0046]

[0083] Furthermore, as used herein, the term "consisting essentially of" allows for the expressly recited elements, but excludes elements that affect the basic or novel characteristics of the invention. As recited herein, the term "consisting of" excludes elements not expressly recited.

[0047]

[0084] B-cell-activating factor (BAFF) is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. BAFF is abundantly produced by monocytes, macrophages, dendritic cells, and stromal cells, which are the major cellular components of the MCL tumor microenvironment. BAFF signaling is essential for the generation of mature B cells and supports the survival of normal and malignant B cells. BAFF has at least three receptors: transmembrane activator and interactor of CAM1 (TACI), B-cell maturation antigen (BCMA), and BAFF receptor (BAFF-R). Of these, BAFF-R is specific for BAFF, while BCMA and TACI share another homologous ligand, APRIL. Signaling through BAFF-R mediates B-cell survival. Virtually all mature B-cell leukemias and lymphomas express the BAFF receptor. Although early stage B cells, the counterparts of acute lymphocytic leukemia (ALL), do not express BAFF-R, cells from patients with several cancers, including ALL and mantle cell lymphoma (MCL), express high levels of BAFF-R. Furthermore, because BAFF-R is only expressed on mature B cells, it has become an attractive target for targeting and reducing side effects caused by off-target interactions. Therefore, BAFF-R offers a targeted opportunity for treating such cancers, as well as autoimmune diseases, in which elevated serum BAFF levels are often present.

[0048]

[0085] One example according to the present disclosure is a method of treating or preventing a disease or condition by targeting a receptor for BAFF. Another example according to the present disclosure is a method of treating or preventing a disease or condition by targeting cells that express or overexpress a receptor for BAFF, such as BAFF-R. In an exemplary embodiment, the disease or condition is a cancer, such as a malignant hematological disease. In one embodiment, the malignant hematological disease can be any malignant hematological disease in which cancer cells express or overexpress a receptor for BAFF, including, but not limited to, acute lymphocytic leukemia, acute myeloid leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, hairy cell leukemia, diffuse large B-cell lymphoma, mantle cell lymphoma, follicular lymphoma, marginal zone lymphoma, acute lymphoblastic leukemia, non-Hodgkin's lymphoma, Hodgkin's lymphoma, B-cell malignancies, and multiple myeloma. In another exemplary embodiment, the disease or condition is an autoimmune disease such as systemic lupus erythematosus, Sjogren's syndrome, narcolepsy, diabetes, pancreatitis, Crohn's disease, celiac disease, ankylosing spondylitis, psoriasis, Graves' disease, or rheumatoid arthritis. In another example, the disease or condition is a B-cell-mediated abdominal aortic aneurysm.

[0049]

[0086] Conventional chimeric antigen receptor-T (CAR-T) cells use single-chain variable fragments (Sc-Fv) of antibodies against corresponding tumor target antigens. Indeed, WO 2017 / 214167 reports BAFF-R antibodies that can bind to the human BAFF-R protein and induce antibody-dependent cellular cytotoxicity on BAFF-R-expressing cells. These antibodies can form part of chimeric antigen receptors (CARs) and are used for the treatment of cancer. However, this antibody treatment approach is limited to cells that express BAFF-R. Because the antibody approach is specific to only one receptor, the prior art disclosure is limited to that approach. Provided herein is a BAFF-ligand-based CAR that can be used to target not only BAFF-R but also any receptor of BAFF, including, for example, TACI and BCMA.

[0050]

[0087] Instead of Sc-Fv, the present disclosure uses a ligand approach that seeks out receptors for BAFF, such as BAFF-R, TACI, and BCMA, on the surface of tumor cells, for example, for CAR-T cell immunotherapy for a wide variety of cancers and autoimmune diseases. Using the BAFF protein, BAFF-ligand-based CARs have been produced and are reported herein.

[0051]

[0088] In this disclosure, a "BAFF protein" or "BAFF" refers to any recombinant or naturally occurring form of B cell activator set forth in SEQ ID NO:1, or a variant or analog thereof that maintains BAFF activity (e.g., within at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% activity compared to BAFF). Optionally, the variant or analog has at least 90%, 95%, 96%, 97%, 98%, 99% or 100% amino acid sequence identity (i.e., sequence homology) over all or a portion of SEQ ID NO:1.

[0052]

[0089] As used herein, a "partial sequence" or "BAFF partial sequence" refers to a portion of SEQ ID NO: 1 that maintains BAFF activity similar to that of the entire sequence, particularly the extracellular portion of BAFF that is responsible for binding to the BAFF receptor. An example of a partial sequence is a sequence that contains at least 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% of a naturally occurring BAFF sequence. Sequences with at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity across the partial sequence are also contemplated. In one example, the partial BAFF sequence includes amino acids 82-285 (SEQ ID NO:2) or a sequence having at least 90%, 95%, 96%, 97%, 98%, 99% or 100% amino acid sequence identity to SEQ ID NO:2. In another example, the BAFF partial sequence includes amino acids 134-285 (SEQ ID NO:3) or a sequence having at least 90%, 95%, 96%, 97%, 98%, 99% or 100% amino acid sequence identity to SEQ ID NO:3.

[0053]

[0090] As used herein, "chimeric antigen receptor T cells" or "CAR-T" cells are T cells genetically engineered to produce artificial T cell receptors for use in immunotherapy. A "chimeric antigen receptor" or "CAR" is a receptor protein engineered to confer new capabilities to T cells to target specific proteins. A CAR is a recombinant receptor that provides both antigen binding and T cell activation functions. In an example according to the present disclosure, CAR-T cells are engineered to target the receptor for BAFF using BAFF as a ligand. CAR-T cell therapy is based on the recognition of specific tumor antigens by genetically modified T cells, followed by intracellular signaling and T cell activation, which subsequently destroys tumor cells. In another example of the present disclosure, natural killer (NK) cells or natural killer T (NKT) cells are engineered to express a CAR.

[0054]

[0091] The present disclosure relates to CARs engineered to express a BAFF ligand. Figure 1 shows a schematic example of how a CAR according to the present disclosure can be designed. In one example, the CAR expresses the complete sequence of native human BAFF, i.e., SEQ ID NO: 1. In another example according to the present disclosure, the CAR expresses a partial sequence of BAFF. In one embodiment, The partial sequence comprises the extracellular domain of BAFF. In another embodiment, the partial sequence comprises a domain involved in receptor binding, such as the BAFF-R, TACI, or BCMA binding domain. In one embodiment, the partial sequence comprises amino acids 82-285 of BAFF (SEQ ID NO:2). In another embodiment, the partial sequence comprises amino acids 134-285 of BAFF (SEQ ID NO:3). In another example, a BAFF sequence (full or partial) can be incorporated into a construct to replace the BAFF domain to reverse the amino acid sequence. In other words, the amino acid normally at the C-terminus in the native sequence becomes the amine-terminus of the sequence, and the amino acid normally at the N-terminus becomes the C-terminus of the sequence.

[0055]

[0092] The CAR can further comprise one or more hinge domains. In one example, the hinge domain comprises the hinge domain of CD8α (SEQ ID NO: 4), or a partial sequence thereof. In another example, the hinge domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 4. In another example, the hinge domain comprises the hinge domain of IgG1 (SEQ ID NO: 5), or a partial sequence thereof. In another example, the hinge domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 5. In yet another example, a CAR cell of the present disclosure comprises the hinge domain of CD28. In yet another example, a CAR cell of the present disclosure comprises the hinge domain of FcγRIII.

[0056]

[0093] The CAR further comprises one or more transmembrane domains. In one example, the CAR comprises a transmembrane domain of CD8α, such as the transmembrane domain of SEQ ID NO: 6. In another example, the transmembrane domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 6. In another example, the CAR comprises a transmembrane domain of CD28, such as the transmembrane domain of SEQ ID NO: 7. In another example, the transmembrane domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 7. In one embodiment, the CAR comprises a hinge domain and a transmembrane domain.

[0057]

[0094] The CAR can further comprise one or more intracellular domains. In one example, the CAR comprises an intracellular domain of 41BB, such as SEQ ID NO: 8. In another example, the intracellular domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 8. In another example, the CAR comprises an intracellular domain of CD28, such as the intracellular domain disclosed in SEQ ID NO: 9. In another example, the intracellular domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 9. In yet another embodiment, the CAR comprises an intracellular domain of CD3-zeta, such as the intracellular domain disclosed in SEQ ID NO: 10. In another example, the intracellular domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 10. In yet another example, the CAR comprises the intracellular domain of OX40 (SEQ ID NO: 11). In another example, the intracellular domain comprises an amino acid sequence having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 11. In accordance with the present disclosure, a CAR can comprise more than one intracellular domain. In one embodiment, a CAR comprises a hinge domain, a transmembrane domain, and one or more intracellular domains.

[0058]

[0095] The CAR can further comprise a signaling peptide. In one example, the signaling peptide is a peptide according to SEQ ID NO: 21 or a peptide having at least 90%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to SEQ ID NO: 21. In another example, the signaling peptide is a peptide according to SEQ ID NO: 22. or a peptide having at least 90%, 95%, 96%, 97%, 98%, 99% or 100% amino acid sequence identity to SEQ ID NO: 22. In one embodiment, the CAR comprises a hinge domain, a signaling domain, a transmembrane domain, and one or more intracellular domains.

[0059]

[0096] Because the distance between T cells and target cells is an important factor affecting tumor recognition and cytotoxicity, a linker domain can be incorporated between BAFF and the hinge domain or between the hinge domain and the transmembrane domain. In some embodiments, the linker is -(CH2) n It contains a simple alkyl chain such as a CH3 unit, where n is the number of CH2 groups, It can vary from 1 to 100, preferably from 1 to 50, 1 to 20, or 1 to 10. In another example, the linker can be a peptide of 1 to 50 amino acids, such as 1 to 20 amino acids, or 1 to 10 amino acids. In a preferred embodiment, the linker comprises SEQ ID NO: 12, or a variant thereof having at least 85% sequence homology to SEQ ID NO: 12.

[0060]

[0097] Figure 2 shows schematic diagrams of six exemplary CAR constructs according to the present disclosure. The top schematic includes the complete BAFF sequence, of which SEQ ID NO: 15 is an example. The second schematic utilizes a partial BAFF sequence but is otherwise identical to the top schematic. SEQ ID NOs: 16 and 17 are examples of such constructs. The third and bottom schematics use BAFF and partial BAFF sequences, respectively, but incorporate different hinge, transmembrane, and intracellular regions. SEQ ID NO: 21 and SEQ ID NOs: 22 and 23, respectively, are represented by these schematic diagrams.

[0061]

[0098] The following examples are illustrative and are not intended to limit the scope of the invention as claimed.

[0099] [Example]

[0062]

[0100] Example 1 ALL cells express BAFF-R

[0101] To confirm BAFF-R expression in ALL cells, 359 pediatric patient samples and 147 adult ALL patient samples were compared with PBMCs from 74 healthy donors using the Haferlach Leukemia Oncomine database. In this disclosure, "peripheral blood mononuclear cells," "PBMCs," or "mononuclear cells" refer to mononuclear cells isolated from peripheral blood, typically used for anti-cancer immunotherapy. PBMCs may be obtained from healthy individuals, patients at risk for cancer, or cancer patients. Collected blood samples (30 mL) from healthy donors were processed to isolate peripheral blood mononuclear cells (PBMCs) by density gradient separation using Ficoll-Paque. The samples were diluted with 1x volume of PBS (pH 7.2), and the diluted blood (30 mL) was layered over 15 mL of Ficoll-Paque in a 50 mL conical tube. The samples were centrifuged (400 x g, 30 min) in a swing-cage rotor without a brake at 20°C. The resulting upper layer was aspirated, leaving the PBMC layer undisturbed. The PBMC layer was transferred to a new 50 mL conical tube, which was then filled with PBS and centrifuged (300 × g, 10 min) at 20 °C. The cell pellet was resuspended in PBS and centrifuged (300 × g, 10 min) at 20 °C. Cells were collected at a concentration of 1 × 10 8 The cells were resuspended in 1× MojoSort buffer at a density of 1 / mL. CD3+ T cells were then purified using the MojoSort Human CD3 T Cell Isolation Kit (Biolegend).

[0063]

[0102] As seen in Figure 3, mRNA expression was significantly increased in both ALL patient samples. Figure 3 shows a significant increase in BAFF-R expression in children (Figure 3, 2) and adults (Figure 3) compared to healthy donors (1), indicating that BAFF-R levels are increased in ALL cells compared to healthy cells.

[0064]

[0103] BAFF-R expression was also measured in newly diagnosed ALL cells at the time of diagnosis. Using flow cytometry (see Vicioso et al., "Combination Therapy for Treating Advanced Drug-Resistant Acute Lymphoblastic Leukemia," Cancer Immun. Res. 7, 1106-1119 (2019), hereby incorporated by reference for methods), levels of BAFF-R expression in newly diagnosed (Figure 4, bottom left) and relapsed (Figure 4, bottom right) ALL patients were measured and compared with Jurkat (negative control, top left) and Jeko-1 (positive control, top right) cells. In all graphs, the left column represents the unstained BAFF-R positive control, and the right column represents cells stained with anti-BAFF-R antibody.

[0065]

[0104] Example 2 Development of BAFF-CAR-T cells

[0105] The various BAFF-CAR-T cell designs are discussed above. The constructs were designed to contain the BAFF protein (full or partial sequence), a hinge domain, a transmembrane domain, and one or more intracellular domains. The constructs may also optionally contain an extracellular signaling domain and a linker domain to optimize spacing. Each construct was cloned into a third-generation lentiviral vector and packaged in HEK293T cells.

[0066]

[0106] Human PBMC cells were used to collect and purify CD3+ T cells as described above. T cells were activated using Dynabeads human T-activator CD3 / CD28 (Gibco / Invitrogen). 1 × 106 For CD3+ T cell activation, 25 µL of Dynabeads were mixed with T cells in 1.5 mL of complete culture medium (advanced RPMI medium 1640 with 2 mM L-glutamine, 10% FBS, and 100 U / mL penicillin / streptomycin) in the presence of 50 U / mL interleukin-2 (IL-2) (PeproTech). Cells were resuspended in culture medium along with the beads and distributed into one well of a 24-well plate. Cells were cultured at 37 °C in a 5% CO2 incubator for 24-48 hours before viral infection with concentrated lentivirus containing BAFF CAR.

[0067]

[0107] The production of lentiviral supernatant containing BAFF CAR was achieved as follows: Lentiviral supernatant was produced using the packaging cell line, 293FT. Healthy 293FT cells were cultured in DMEM with 10% FBS and 100 U / mL penicillin / streptomycin. The day before vector transfection, 293FT cells were transfected at 5 × 10 6The cells were split into 10cm tissue culture plates. Four plates of 293FT cells were required to generate enough supernatant for lentivirus concentration. For one 10cm plate, 200µL of Opti-MEM medium was added to an Eppendorf tube, followed by 3750ng of the packaging plasmid psPax2, 1250ng of the envelope plasmid pMD2G, and 5000ng of the BAFF CAR vector. The tube was gently mixed, and then 10µL of X-tremeGENE HP Transfection Reagent (Sigma, catalog no. 06 366 236 001) was added, mixed gently, and incubated at room temperature for 20 minutes. The DNA mixture was added dropwise to a 10cm 293FT plate and incubated at 37°C in a 5% CO2 incubator. After overnight incubation, the medium was removed and replaced with 6mL of fresh complete DMEM medium. Supernatants from four plates (23 mL total) were collected into 50 mL conical tubes at 48 and 72 hours after vector transfection and centrifuged at 500 × g for 10 minutes to remove cell debris. 23 mL of the clear supernatant was transferred to a new 50 mL conical tube, to which 7.6 mL of Lenti-X concentrator (Clontech) was added, mixed, and incubated overnight at 4°C. The supernatant was centrifuged (1500 × g, 45 min, 4°C), and the supernatant was removed to yield an off-white pellet. The pellet was resuspended in 1 mL of complete advanced RMPI medium with IL-2 and prepared for viral transduction into CD3+ T cells.

[0068]

[0108] Approximately 1×10 6 Activated T cells were enriched with Dynbeads and BAFF CA The T cells were resuspended in 1 mL of complete advanced RPMI medium containing R and dispensed in 100 μL volumes into each of 10–12 wells of a round-bottom 96-well plate. The T cells were spinoculated (3480 rpm, 22°C, 90 min). After centrifugation, the cells were resuspended, collected with Dynabeads, and then re-isolated into 24-well plates. An additional 1 mL of complete advanced RPMI medium was added along with IL-2 50 U / mL, IL-7 10 ng / mL, and IL-15 5 ng / mL. The T cells were cultured in a 5% CO2 incubator at 37°C. When the medium turned yellow, fresh medium containing cytokines was added. The Dynabeads were removed 4–5 days after initial T cell activation. The transduced T cells were exponentially expanded 5–8 days after activation. The T cell cultures reached 3×10 6 Cells were maintained at a density below 1 / mL and further supplemented with complete culture medium containing cytokines as needed. BAFF CAR transduction efficiency in T cells was monitored for 72 hours after viral transduction. Transduction was confirmed by the presence of GFP-positive cells or BAFF staining using an anti-human BAFF antibody APC conjugate (Biolegend). BAFF CAR T cells were used on days 7–10 for in vitro and in vivo experiments or frozen in 95% FBS + 5% DMSO in liquid nitrogen for later use.

[0069]

[0109] In one example, T cells are isolated from human blood, activated, and immunized with the lentivirus of SEQ ID NO: 15. The CAR-T cells were transduced using virus particles. Transduction efficiency was assessed by GFP expression (data not shown). Approximately 27% of the CAR-T cells expressed the protein corresponding to SEQ ID NO: 15.

[0070]

[0110] Example 3 CAR-T cells kill leukemia cells in vitro

[0111] MCL cell line Jeko-1 and ALL cell line RS4;11 were tumor-targeted. The efficacy of BAFF CAR-T cells was tested using SEQ ID NO: 15 and SEQ ID NO: 17. Cells were grown and transduced as described above using SEQ ID NO: 15 and SEQ ID NO: 17. Tumor cell killing by BAFF CAR-T cells was analyzed using a calcein-AM assay purchased from Life Technologies. Target tumor cells (10x10 6 ) were labeled with calcein-AM (0.5 μmol / L) for 30 min at 37°C. Following staining, cells were washed with PBS, counted using trypan blue (Sigma), and incubated with BAFF CAR-T cells at a 5:1 or 10:1 ratio as indicated for 4–6 h. The percentage of viable tumor cells was analyzed by Annexin / PI-negative and CD19-positive staining, and the percentage of lysis was determined according to the following formula:

[0071]

number

[0072] “AFU average spontaneous release” is calcein-AM release by target cells alone (in the absence of T cells); "AFU mean maximal release" is the calcein-AM release by target cells upon detergent lysis; and "AFU average experimental release" is calcein-AM release by target cells mixed with BAFF CAR-T cells.

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[0112] Figure 5 shows control T cells (left column), CAR-T cells expressing SEQ ID NO: 15 Figure 1 shows the % cell killing (y-axis) for CAR-T cells expressing SEQ ID NO: 15 (middle left), CAR-T cells expressing SEQ ID NO: 17 (middle right), and anti-CD19 CAR-T cells (right). In the MCL Jeko-1 cell line, cell killing following treatment with control T cells resulted in approximately 45% MCL cell death, while treatment with CD19 CAR-T cells resulted in over 90% cell death. Treatment with CAR-T cells expressing SEQ ID NO: 15 and SEQ ID NO: 17 resulted in approximately 60% cell death for both constructs. In RS4;11 ALL cells, CAR-T cells resulted in approximately 80% and 85% cell death. Treatment with the negative control showed approximately 60% cell death, while treatment with the positive control resulted in nearly 100% cell death. These results demonstrate the feasibility of treating cancer cells with the CAR-T cells of the present disclosure.

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[0113] Cytotoxicity of RS4;11 cells was measured using constructs SEQ ID NO: 15 and SEQ ID NO: 22. The effect of treatment of RS4 cells with a T cell control (left), CAR-T cells expressing SEQ ID NO: 15 (center), and CAR-T cells expressing SEQ ID NO: 22 (right) was further investigated. Figure 6 (top) shows the effect of treatment of RS4 cells with a T cell control (left), CAR-T cells expressing SEQ ID NO: 15 (center), and CAR-T cells expressing SEQ ID NO: 22 (right). Treatment with the negative control resulted in cell death of less than 10% of the cells. Treatment with CAR-T cells expressing SEQ ID NO: 15 and SEQ ID NO: 22 resulted in approximately 40% and 25% cell killing, respectively.

[0075]

[0114] Cytotoxicity in Jeko-1 and RS4;11 cells was also partially suppressed by SEQ ID NO:17. These studies were performed following exposure to BAFF CAR-T cells expressing a construct expressing the BAFF sequence. Following overnight incubation with control T cells (left), CAR-T cells (5:1 BAFF CAR-T vs. Jeko-1) (center), and 10:1 (right), we found that in all cases, CAR-T cells killed MCL and ALL cells more efficiently than controls. More specifically, at a 5:1 ratio of BAFF CAR-T cells to tumor cells, cell death was approximately 40% and 30% for Jeko-1 and RS4;11 cells, respectively. Cell death was higher, as expected, at a 10:1 exposure, reaching approximately 60% and 40% for Jeko-1 and RS4;11 cells, respectively. By comparison, cell death in control T cells was less than 20% in both cases.

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[0115] Example 5 Degranulation of CAR-T cells

[0116] We investigated CAR-T cell degranulation following incubation with Jeko-1. Lysosomal membrane protein-1 (LAMP-1 or CD107a) has been described as a marker for CD8+ T cell degranulation following stimulation. Cells were incubated with anti-CD107 antibody and analyzed for CD107-positive staining using flow cytometry.

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[0117] Figure 7 shows the results of CAR-T cells alone (left) and CAR T and Jeko-1 cells (right). ) incubation. As can be seen, the percentage of CAR-T cells exhibiting degranulation was approximately six-fold higher when incubated with cancer cells compared to incubation alone. This suggests that CAR-T cells according to the present disclosure recognize the tested MCL cells and are activated in the presence of these cells.

[0078]

[0118] Example 6 Granzyme B Release Studies

[0119] Granzyme B is a key molecule responsible for T cell-mediated cell death. Granzyme B is a serine protease commonly found in the granules of natural killer cells (NK cells) and cytotoxic T cells. This molecule is secreted by these cells together with the pore-forming protein perforin to mediate apoptosis in target cells. Thus, the release of granzyme B is associated with the incubation of cancer cells in the presence of BAFF-CAR-T cells. The CAR-T cell and CAR-T target cell co-culture plates were used for measurement following incubation. Supernatants were collected from the CAR-T cell or CAR-T target cell co-culture plates. A human GranzymeB Elisa kit (Biolegend) was used, and experiments were performed as specified in the manufacturer's instructions. GranzymeB binding was detected using a secondary antibody, streptavidin-HRP, and TMB substrate solution (provided with the designated ELISA kit). Substrate conversion was stopped after 20 minutes with 100 μL of stop solution (2N H2SO4) (Biolegend). Plates were washed with PBS plus 0.05% Tween 20 between incubations. The manufacturer's assay diluent or RPMI medium (Sigma) was used as a negative control, and specific standard proteins were used as positive controls. Standard reconstitution and curves were generated for each assay according to the manufacturer's instructions. Optical density values ​​were measured using a microplate reader (Bio-Rad iMark) set at 450 nm. The data were obtained using a microplate reader.

[0079] detail

[0120] Figure 8 shows CAR-T cells according to the present disclosure treated with both RS4;11 or Jeko-1 This shows that granzyme B is released when CAR-T cells are incubated with the cells. The cell ratio (5:1 or 10:1) did not appear to make a difference in the level of granzyme released, nor did the cell type. In all cases, granzyme B was released in approximately the same amount. When CAR-T cells were incubated alone, no granzyme B excretion was detected (left). This suggests that CAR-T cells according to the present disclosure recognize the leukemia cells tested and are activated in the presence of these cells.

[0080]

[0121] Example 7 BAFF-CAR T cells inhibit tumor growth in vivo

[0122] BAFF-CAR T cells expressing SEQ ID NO: 17 were used in in vitro studies In vivo studies were performed to determine whether Jeko-1 cells (1 × 10 6 BAFF-CAR-T cells) were injected subcutaneously into immunocompromised mice. 14 days after tumor cell implantation, the mice had palpable tumors. Mice received intratumoral injections of PBS solution (control), control T cells, or BAFF-CAR-T cells. Tumor size was monitored at 15, 18, 20, 22, and 25 days after tumor cell injection.

[0081]

[0123] Figure 9 shows the tumor burden (mm 3 The figure shows a plot of the number of days (x-axis) versus the number of days (y-axis). As shown, tumors treated with the PBS control and T cell control showed continued, uncontrolled tumor growth following treatment. Tumors treated with BAFF-CAR-T cells continued to grow for 1 day following treatment, at which point tumor growth not only stopped but also shrank. On day 25, after 11 days of treatment, the BAFF-CAR-T cell-treated tumors were almost completely gone. Figure 10 shows images of Jeko-1 tumor-bearing mice treated with PBS (left) and BAFF-CAR-T cells (right).

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[0124] Finally, survival of mice treated with BAFF-CAR-T cells was significantly greater than that of mice treated with PBS and The survival time was extended when compared with the control T cells. The PBS-treated group experienced 100% survival until approximately 35 days after tumor inoculation, and by 38 days after inoculation, all mice had died or were humanely euthanized due to tumor burden. Treatment with control T cells extended survival by approximately 2 days. Mice treated with BAFF-CAR-T cells experienced 100% survival until approximately day 45, and all mice had died or were euthanized by 60 days after inoculation.

[0083]

[0125] The above-described embodiments of the present disclosure may deviate substantially from the spirit and various principles of the present disclosure. Numerous variations and modifications may be made without departing from the spirit and scope of the present disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and are protected by the following claims. This specification includes the disclosure of the invention below. [Item 1] An immune cell expressing a chimeric antigen receptor that recognizes a receptor for B cell activating factor (BAFF), wherein the immune cell is selected from a cytotoxic T lymphocyte, a natural killer cell, and a natural killer T cell, and the chimeric antigen receptor is selected from SEQ ID NO: 18, a variant having 95% or more sequence identity to SEQ ID NO: 18, SEQ ID NO: 19, a variant having 95% or more sequence identity to SEQ ID NO: 19, The immune cell is selected from the group consisting of SEQ ID NO: 20 and a variant having 95% or greater sequence homology to SEQ ID NO: 20. [Item 2] The immune cell described in Item 1, wherein the chimeric antigen receptor further comprises a signaling peptide. [Item 3] The immune cell according to Item 2, wherein the chimeric antigen receptor is selected from the group consisting of SEQ ID NO: 21, a variant having 95% or more sequence identity to SEQ ID NO: 21, SEQ ID NO: 22, a variant having 95% or more sequence identity to SEQ ID NO: 22, SEQ ID NO: 23, and a variant having 95% or more sequence identity to SEQ ID NO: 23. [Item 4] The immune cells described in Item 1, wherein the immune cells are isolated from a human. [Item 5] The immune cell according to Item 1, wherein the immune cell is a cytotoxic T lymphocyte. [Item 6] The immune cell according to Item 1, wherein the immune cell is a natural killer cell or a natural killer T cell. [Item 7] The immune cell described in Item 1, wherein the receptor for BAFF is selected from the group consisting of B-cell maturation antigen, transmembrane activating factor and CAML interactor, and BAFF receptor. [Item 8] A method for treating a patient in need thereof, comprising the step of administering to a patient a therapeutically effective amount of a composition comprising immune cells expressing a chimeric antigen receptor that recognizes a receptor for B-cell activating factor (BAFF), wherein the immune cells are selected from cytotoxic T lymphocytes, natural killer cells, and natural killer T cells, and the chimeric antigen receptor is selected from the group consisting of SEQ ID NO: 18, a variant having 95% or greater sequence identity to SEQ ID NO: 18, SEQ ID NO: 19, a variant having 95% or greater sequence identity to SEQ ID NO: 19, SEQ ID NO: 20, and a variant having 95% or greater sequence identity to SEQ ID NO: 20. [Item 9] The method according to Item 8, wherein the patient has been diagnosed with cancer. [Item 10] The method according to Item 9, wherein the cancer is a malignant blood disease. [Item 11] The method according to Item 10, wherein the malignant blood disease is leukemia. [Item 12] The method of Item 8, wherein the patient has been diagnosed with an autoimmune disease. [Item 13] The method according to Item 12, wherein the autoimmune disease is selected from systemic lupus erythematosus, Sjogren's syndrome, narcolepsy, diabetes, pancreatitis, Crohn's disease, celiac disease, ankylosing spondylitis, psoriasis, Graves' disease, and rheumatoid arthritis. [Item 14] The method of Item 8, wherein the composition is administered simultaneously with one or more chemotherapeutic agents. [Item 15] The method described in Item 8, wherein the chimeric antigen receptor further comprises a signaling peptide. [Item 16] The method of Item 15, wherein the chimeric antigen receptor is selected from the group consisting of SEQ ID NO: 21, a variant having 95% or more sequence identity to SEQ ID NO: 21, SEQ ID NO: 22, a variant having 95% or more sequence identity to SEQ ID NO: 22, SEQ ID NO: 23, and a variant having 95% or more sequence identity to SEQ ID NO: 23. [Item 17] The method described in Item 8, wherein the immune cells are isolated from a human. [Item 18] The method described in Item 8, wherein the immune cells are cytotoxic T lymphocytes. [Item 19] The method described in Item 8, wherein the immune cells are natural killer cells or natural killer T cells. [Item 20] The method described in Item 8, wherein the receptor for BAFF is selected from the group consisting of B-cell maturation antigen, transmembrane activator and CAML interactor, and BAFF receptor.

Claims

1. 1. An immune cell expressing a chimeric antigen receptor that recognizes a receptor for B-cell activating factor (BAFF), wherein the immune cell is selected from a cytotoxic T lymphocyte, a natural killer cell, and a natural killer T cell, and the chimeric antigen receptor is selected from the group consisting of SEQ ID NO: 18, a variant having 95% or greater sequence identity to SEQ ID NO: 18, SEQ ID NO: 19, a variant having 95% or greater sequence identity to SEQ ID NO: 19, SEQ ID NO: 20, and a variant having 95% or greater sequence identity to SEQ ID NO:

20.

2. The immune cell of claim 1, wherein the chimeric antigen receptor further comprises a signaling peptide.

3. 3. The immune cell of claim 2, wherein the chimeric antigen receptor is selected from the group consisting of SEQ ID NO:21, a variant having 95% or greater sequence identity to SEQ ID NO:21, SEQ ID NO:22, a variant having 95% or greater sequence identity to SEQ ID NO:22, SEQ ID NO:23, and a variant having 95% or greater sequence identity to SEQ ID NO:

23.

4. The immune cell of claim 1 , wherein the immune cell is isolated from a human.

5. The immune cell of claim 1 , wherein the immune cell is a cytotoxic T lymphocyte.

6. The immune cell of claim 1 , wherein the immune cell is a natural killer cell or a natural killer T cell.

7. 2. The immune cell of claim 1, wherein the receptor for BAFF is selected from the group consisting of B-cell maturation antigen, transmembrane activator and CAML interactor, and BAFF receptor.

8. 1. A method of treating a patient in need thereof, comprising the step of administering to the patient a therapeutically effective amount of a composition comprising immune cells expressing a chimeric antigen receptor that recognizes a receptor for B-cell activating factor (BAFF), wherein the immune cells are selected from cytotoxic T lymphocytes, natural killer cells, and natural killer T cells, and the chimeric antigen receptor is selected from the group consisting of SEQ ID NO: 18, a variant having 95% or greater sequence identity to SEQ ID NO: 18, SEQ ID NO: 19, a variant having 95% or greater sequence identity to SEQ ID NO: 19, SEQ ID NO: 20, and a variant having 95% or greater sequence identity to SEQ ID NO:

20.

9. 9. The method of claim 8, wherein the patient has been diagnosed with cancer.

10. 10. The method of claim 9, wherein the cancer is a hematological malignancy.

11. 11. The method of claim 10, wherein the malignant hematological disease is leukemia.

12. 9. The method of claim 8, wherein the patient has been diagnosed with an autoimmune disease.

13. 13. The method of claim 12, wherein the autoimmune disease is selected from systemic lupus erythematosus, Sjogren's syndrome, narcolepsy, diabetes, pancreatitis, Crohn's disease, celiac disease, ankylosing spondylitis, psoriasis, Graves' disease, and rheumatoid arthritis.

14. 10. The method of claim 8, wherein the composition is co-administered with one or more chemotherapeutic agents.

15. 9. The method of claim 8, wherein the chimeric antigen receptor further comprises a signaling peptide.

16. 16. The method of claim 15, wherein the chimeric antigen receptor is selected from the group consisting of SEQ ID NO:21, a variant having 95% or greater sequence identity to SEQ ID NO:21, SEQ ID NO:22, a variant having 95% or greater sequence identity to SEQ ID NO:22, SEQ ID NO:23, and a variant having 95% or greater sequence identity to SEQ ID NO:

23.

17. 9. The method of claim 8, wherein the immune cells are isolated from a human.

18. The method of claim 8, wherein the immune cells are cytotoxic T lymphocytes.

19. The method of claim 8, wherein the immune cells are natural killer cells or natural killer T cells.

20. 9. The method of claim 8, wherein the receptor for BAFF is selected from the group consisting of B-cell maturation antigen, transmembrane activator and CAML interactor, and BAFF receptor.

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