7results about How to "High transduction efficiency" patented technology

The application belongs to the technical field of cell engineering, and particularly relates to a bispecific antibody targeting CD22 and CD19, a chimeric antigen receptor thereof and application. In the bispecific antibody, a CD22 light chain and a CD22 heavy chain are connected through a linker 4 to form a CD22 single-chain antibody, and a CD19 light chain and a CD19 heavy chain are connected through a linker 4 to form a CD19 single-chain antibody, which comprises one of the following structures: (1) the CD22 single-chain antibody and the CD19 single-chain antibody are connected through a linker 1 or a liner 2; (2) the two ends of the CD19 single-chain antibody are connected with the CD22 light chain and the CD22 heavy chain through a linker 3, respectively. The chimeric antigen receptor provided by the application can simultaneously target two different tumor antigens, improve the killing of tumor cells, reduce the probability of immune escape, and reduce the tumor recurrence rate after CAR-T treatment.

This invention discloses a nucleic acid molecule encoding a modified retroviral Gag protein and its applications. The Gag protein contains an engineered acylated tag sequence at its N-terminus, comprising: a glycine residue at the second position after the initiating methionine for myristylation modification; and / or a cysteine ​​residue in the N-terminal region for palmitoylation modification. The tag sequence is selected from SEQ ID NO:1, 3-9, or derivative amino acid sequences having at least 80% identity and retaining function. Preferably, the modification involves replacing the first 9 amino acids at the N-terminus of the wild-type HIV-1 Gag protein with the aforementioned tag to enhance membrane anchoring and improve viral packaging efficiency. This invention also provides packaging plasmids containing this molecule, host cells, packaging systems, and preparation methods. This invention can significantly improve viral yield and titer, and is particularly suitable for overcoming the efficiency bottleneck in packaging large-load lentiviruses of 7-10 kb.

The invention discloses a novel adeno-associated virus variant library for gene and cell therapy as well as construction and application of the novel adeno-associated virus variant library, and belongs to the field of biological medicines. Through high-throughput sequencing and gene editing, an AAV variant library containing a large number of mutants is constructed, the construction efficiency is improved, the diversity of the mutants is ensured, the cap gene of AAV is modified by the variant library through a site-directed mutagenesis technology, the transduction efficiency of human immune cells is improved, the limitation of an existing AAV modification method is overcome, and the AAV mutant library has good application prospects. The constructed novel AAV variant library has higher packaging efficiency, lower cytotoxicity and better adaptability, and provides more choices for development of gene therapy drugs; the screened novel AAV6 variant P482L has remarkable advantages in the aspects of transduction efficiency, safety and the like, and becomes a potential candidate vector in the field of gene therapy; the invention not only accelerates the progress of new drug research and development, but also provides a new tool and method for treating hereditary diseases, tumors and the like, and promotes the development of the field of gene therapy.

The application provides a truncated transposase, a transposon system and application thereof. Compared with a wild-type PS transposase, the truncated transposase lacks 1-50 amino acids at the C terminal of the wild-type PS transposase, preferably 44 amino acids. By deleting the amino acids at the C terminal of the transposase which have less influence on transposition, the length of the transposase is shortened, which is beneficial to the expression of the transposase and the preparation of a fusion protein, so that a transposase or a fusion protein thereof with higher catalytic activity and smaller size is obtained. The application also provides a fusion protein of the transposase, which is preferably fused with a leucine zipper through a linker, and a transposon system comprising the transposase and the transposon, which has great application value in the transgenic industry.

The invention relates to the technical field of AAV vectors, in particular to a preparation method of an efficient AAV vector for gene therapy and an AVV vector, and the preparation method comprises the following steps: (1) creating a novel AAV capsid protein library through a DNA shuffling method; and (2) obtaining the AAV variant with high transduction efficiency through directed evolution screening, wherein the method specifically comprises the following steps: a) constructing a screening vector system containing a reporter gene; b) performing multiple rounds of screening in the HEK293T cells; c) sorting by a flow cytometry to obtain an AAV variant with high transduction efficiency; (3) optimizing an AAV genome packaging sequence; and (4) carrying out virus packaging and purification on the obtained AAV vector, and recombining dominant sequences of different serotypes on a molecular level through a DNA shuffling method, so that the diversity and quality of a gene pool are remarkably improved.

The application relates to a method for preparing a wearable potential ion sensor based on a conductive polymer nanofiber membrane and belongs to the field of electrochemical sensing. The method mainly comprises the following steps: (1) conductive polymer monomer solution and initiator-crosslinking agent mixed solution are successively drop-coated on the surface of an electrode, the latter induces monomer assembly polymerization, a conductive polymer nanofiber membrane is obtained, and drying is performed; (2) an ion-selective membrane dispersion liquid is prepared according to a certain proportion and is dropwise added to the electrode, and film drying is performed; (3) after the prepared electrode is dried overnight in the dark, the electrode is placed in a prepared standard ion solution (to-be-measured ion) for pretreatment; and (4) the electrode is placed in ion solutions with different concentrations for testing, the relationship between ion concentration and voltage is obtained, a standard curve and a linear equation are obtained, and monitoring of ion concentration in sweat is realized. The wearable potential ion sensor prepared by the method can realize high-sensitivity real-time monitoring of ions in sweat.

The invention relates to a method and a kit for improving lentivirus transduction efficiency and transduction stability of TIL cells. The invention relates to the technical field of biology. Specifically, the invention provides a method and a kit for promoting the lentivirus transduction efficiency and the transduction stability of TIL cells, BX-795 is added in the lentivirus infection process, the transduction efficiency can be improved to 60% or above, the transduction stability can be remarkably improved, and the viability of the TIL cells is not obviously influenced. The method for improving the lentivirus transduction efficiency and transduction stability of the TIL cells can be applied to obtaining genetically engineered TIL cells and promoting development and application of TIL cell therapy.