Strain specific B2M and HLA-A3 expression analysis in wild type C57BL/6 mice and homozygous humanized B-HLA-A3.1 mice by flow cytometry. Splenocytes(A) and blood(B) were collected from wild type C57BL/6 mice (+/+) and homozygous B-HLA-A3.1 mice (H/H), respectively, and analyzed by flow cytometry with species-specific anti-HLA-A3 and anti-B2M antibody. HLA-A3 and human B2M were exclusively detectable in homozygous B-HLA-A3.1 mice. 

Frequency of leukocyte subpopulations in spleen by flow cytometry. Splenocytes were isolated from wild type C57BL/6 mice and homozygous B-HLA-A3.1 mice (n=4, 2 female and 2 male, 7-week-old). A. Flow cytometry analysis of the splenocytes was performed to assess the frequency of leukocyte subpopulations. B. Frequency of T cell subpopulations. Percentages of T cells, B cells, NK cells, dendritic cells, granulocytes, monocytes, macrophages and Tregs in B-HLA-A3.1 mice were similar to those in C57BL/6 mice. Percent of CD8+ T cells were significantly decreased while percent of CD4+ T cells were significantly increased, demonstrating that introduction of hB2M-HLA-A3.1-H-2D in place of mouse B2M may affected the development of CD8 + T cells, which in turn affected the proportion of T cell subtypes in the spleen. Values are expressed as mean ± SEM.