动物造模 z-bio 2022-09-05 475

　　Objective To establish a mouse model of chronic lymphocytic choriomeningitis virus LCMV-CL13 infection, and to analyze its possibility as a model for high-frequency mutation of B cell receptors.

　　Methods C57BL/6N mice were inoculated with 2×106PFU dose of LCMV-CL13 virus via tail vein route, and samples were collected on the 10th, 20th, 30th, 40th, 50th, 60th, and 70th days after infection. The proportions of CD4+ T, CD8+ T, CD19+ B cells in peripheral blood and B cells in spleen germinal center were detected and analyzed, and the gene abundance and mutation rate of BCR V region were analyzed by immune repertoire sequencing.

　　Results The virus replication at the level of 1×106copies/μL was detected in LCMV-CL13 virus-infected mice; during the infection plateau, the proportion of CD4+T cells in peripheral blood of mice gradually increased (13.15%±0.72%), CD8+T cells The cells first decreased (2.17% ± 0.40%) and then gradually recovered (6. 65% ± 0. 52%). The proportions of CD19+ B cells and germinal center B cells increased to (40.32% ± 0.46%) and (10.03% ± 0.52%), respectively. 0.60%); sequencing results showed that the frequency of BCR heavy chain V gene usage decreased and the mutation rate increased significantly (P<0.05).

　　Conclusion The LCMV-CL13 chronic infection mouse model was successfully established; this model can be used for the study of BCR mutation, which lays a foundation for the study of B cell hypermutation caused by chronic viral infection.