NATURAL-KILLER-CELLS AND GAMMA-DELTA T-CELLS IN SCLERODERMA - RELATIONSHIP TO DISEASE DURATION AND ANTI-SCL-70 ANTIBODIES

Objectives-To examine the expression of the natural killer (NK) antige n CD56, and T cell receptor delta chain antigen (TCR delta), expressed on the gamma delta T cell subset, in patients with scleroderma, and t o correlate levels of expression with clinical characteristics. Method s-Peripheral blood mononuclear cells (PBMCs) from 15 patients with scl eroderma and 11 controls were obtained from heparinised blood on a fic oll/hypaque gradient, stained with monoclonal antibodies, and examined by flow cytometry for expression of CD56 and TCR delta. Results-Overa ll, the proportion of PBMCs expressing CD56 in the patient group (14.4 (SEM 2.6)%) was not significantly different from controls (8.75 (2.6) %). The greatest levels of expression were found in patients late (mor e than three years) in their disease course (18.1 (3.3)%) and in patie nts who did not express anti-Scl-70 antibodies (17.1 (3.5)%). The prop ortion of gamma delta T cells was significantly lower in the patient g roup (1.61 (0.52)% v control 2.61 (0.46)%) (p < 0.05). Patients early in their disease or with anti-Scl-70 antibodies accounted for the redu ction in gamma delta T cells (0.71 (0.29)% and 0.96 (0.41)%) (p < 0.01 and p < 0.05, respectively). Conclusions-This study emphasises that N K and gamma delta T cell numbers vary depending upon patient character istics and may help explain prior contradictory reports. Decreased num bers of gamma delta T cells were seen in scleroderma patients, especia lly those with anti-Scl-70 antibodies and a disease duration of less t han three years.