Expression of CD45-Restricted Form B in (NZW × BXSB) F1 and MRL/Mp-1pr/1pr Mice

Abstract

Expression of CD45RB on CD4⁺ or CD8⁺ cells in combination with TCRVβ usages (Vβ6, Vβ8.1, Vβ8.2, Vβ11 and Vβ7a) in normal mouse strains (BALB/c and C57BL/6) was compared with autoimmune-prone strains ((NZW × BXSB) F1 and MRL/1pr) at young and old ages. The frequencies, and also the numbers of CD45RB cells in CD4⁺ T cells with various TcR repertoires was significantly less in the autoimmune-prone strains at old ages, while, in normal control strains, they remained unchanged. Furthermore, CD4⁺/CD45RB^- cells are CD4^high and CD62L (L-selectin).^low These findings suggest that most T cells, especially CD4⁺ T cells, in old W/BF1 and old MRL/1pr mice, were activated and this may reflect the elevation of autoantibodies and the progress of autoimmune status in aged autoimmune-prone mice. This will be discussed in relation to the progress of the autoimmune diseases.

Key Words:

• W/B FI mouse
• MRL/1pr mouse
• CD45KR
• TcKVβ