Self-Reactivity and the Expression of Memory MarkersVary Independently in MRL-Mp+/+ and MRL-Mp-lpr/lprMice

摘要

MRL-Mp-lpr/lprmice contain phenotypically abnormal populations of T cells, andexhibit an SLE-like autoimmune disease in which autoantibodies are a prominentfeature. We analyzed the phenotype and T-cell receptor V?expression pattern in CD4+Tcells of this mutant mouse strain to detect abnormalities that could explain theautoimmunity. The CD4+T cells contain two distinct abnormal populations. One ofthese expresses B220 and HSA, and in these and other respects closely resembles theaccumulating CD4–CD8–population. The other expresses a high level of CD44 (Pgp-1),and a high level of the 16A epitope of CD45, and so resembles post-activation T cells.Both of these cell types are exclusive to MRL-Mp-lpr/lpr. We also identified V?5- andV?11-positive CD4+ T cells, in both MRL-Mp-lpr/lprand MRL-Mp-+/+ mice. Weconclude that autoimmune T cells can be detected in these mice, but that they are not thecause of the accumulation of abnormal CD4+and CD4–CD8–cells.