Abnormal distribution of CD45 isoforms expressed by CD4+and CD8+T cells inrheumatoid arthritis

CD45RO+ T cells are referred to as memory or helper-inducer while CD45RA+ T cells are regarded as naive or suppressor-inducer T cells. The former popu lation predominates in the peripheral blood and even more in the synovial f luid of patients with rheumatoid arthritis, to the expense of the latter po pulation. Within the CD45RB+ compartment, there appears to be more of the f ully-differentiated than of the early-differentiated CD4+ T cells. In spite of the fact that these lymphocytes are close to undergoing apoptosis, this programmed cell death is inhibited in the rheumatoid synovium.