动物造模,T细胞缺陷 z-bio 2023-09-12 751

　　1. The homozygous CD4 antigen knockout mice cannot express CD4 on the cell surface. CD8+T cells and myeloid components develop normally. This indicates that expression in ancestral cells and CD4+CD8+thymocytes is not necessary. The antiviral activity of cytotoxic T cells in mutant mice was normal, while the antiviral activity of helper T cells was significantly reduced. Therefore, mutant mice are very useful for studying the function of CD4+helper T cells in immune disorders.

　　2. CD8 gene deficient mice have no expression of CD8 on the surface of T cells, while homozygous mice do not have functional cytotoxic T cells and have a normal CD4+T lymphocyte population. Although the cytotoxic T cell response to homologous and viral antigens in mice was significantly reduced, the proliferative response to homologous antigens and its auxiliary performance on B lymphocytes in vivo were normal. This indicates that CD8 cells are necessary for the maturation and positive selection of cytotoxic T cells restricted by type I MHC, but not for the successful development of helper T cells restricted by type II MHC in intermediate lymphocyte populations (CD8+CD4 TcR - or CD4+CD8+TcR -).

　　3. CD14 gene knockout mice. CD14 gene knockout mice are homozygous and can survive and reproduce. Mouse macrophages cannot produce cytokines involved in LPS response. This non responsiveness is related to the activity damage of NF-kB and c-Jun N-terminal mitogen activated protease (MAPK) pathways, and is a model for analyzing the mechanisms of macrophage and bacterial infection.

　　4. Fc receptor γ Subunit gene knockout of Fc receptor in mice γ Homozygotes of subunit gene knockout mice can survive and reproduce, but lack immunoglobulin Fc receptors γ Subunit (Fcer1g). Fcer1g is an important component of IgG high affinity receptors and is associated with IgG high affinity receptors and T cell receptor CD3 complexes. When lacking immunoglobulin Fc segment receptors γ When subunits are present, CD3 complexes and others become unable to assemble. Although Fcer1g homozygotes produce normal T cells, they cannot phagocytose antibody encapsulated particles and lack NK cell-mediated antibody dependent cytotoxicity and mast cell-mediated allergic reactions, weakening the inflammatory response to immune complexes. This type of mouse can be used to evaluate the function of Fc receptors in humoral and cellular immunity.

　　5. Perforin gene knockout mice (PERFORIN) is a medium released by NK, CTL, LAK and other cytoplasmic particles to kill target cells, and has important significance in anti-tumor, antiviral, and parasitic treatments. In lymphocyte mediated cytotoxicity, perforin and other mediators are released from the cell and act on the target cell. They mainly bind in the form of monomers and insert into the membrane, gradually forming a hollow polymer, which forms a hole of 5-20nm in size on the membrane, allowing water molecules, ions, and other small molecules to form