Abstract
Possible effects of sera from patients with collagen diseases on human EC proliferation in vitro were investigated. EC from umbilical vein were incubated with 20% test serum for 3 days and uptake of 3HTdR by EC was determined. Ten out of 29 PSS and 4 out of 18 Raynaud disease sera remarkably suppressed EC proliferation (below 10% of normal control sera) . On the other hand, only one out of 17 RA sera and none of 14 SLE sera possessed such effect. By morphological observation, this suppressive effect revealed to be cytotoxicity against EC.
The experiment with fractionated serum on Sephadex G-200 gel suggested that this cytotoxic factor eluated with albumin. Possible contribution of this factor to the pathogenesis of vascular damage and Raynaud phenomenon in PSS was discussed.
