TCR1(-PROLIFERATION IN RHEUMATOID-ARTHRITIS() LARGE GRANULAR LYMPHOCYTE)

The T gamma-lymphoproliferative syndrome is characterized by a prolife ration of large granular lymphocytes (LGL). It is often associated wit h neutropenia, and in 30% of cases with rheumatoid arthritis (RA). Phe notypic analysis has demonstrated that in most cases of RA with T gamm a-proliferative disease, the LGL represent T cells with a clonal rearr angement of the alpha/beta T cell receptor (TCR2). Here, three patient s with gamma/delta TCR1(+) LGL proliferation suffering from long-stand ing arthritis and neutropenia are described. The first patient with RA showed an expansion of a heterogeneous CD2(+) CD16(+) CD56(-) LGL pop ulation, of which 30% coexpressed TCR1 with V delta 1 rearrangement. T he second patient with ankylosing spondylitis and RA was suffering fro m proliferation of TCR1(+) (V gamma 9(-), V delta 1(-)), CD2(+) CD16(- ) CD56(-) LGL with low coexpression of CD8. The third patient with RA was suffering from a proliferation of TCR1(+) (V delta 1(+), V gamma 9 (-)) CD4(-) CD8(-) CD16(-) CD56(-) lymphocytes. On the basis of these unusual findings, the pathogenetic role of TCR1(+) T cells in RA is di scussed.