Serum levels of soluble tumor necrosis factor alpha receptor I (sTNF-RI) we
re elevated in patients with lepromatous (LL) reactional-state type II lepr
osy, and sTNF-RII levels were increased in patients with full tuberculoid (
TT) or LL type II leprosy. The sTNF-R in sera from patients with type II le
prosy, but not other forms of leprosy, inhibited recombinant TNF cytolytic
activities in vitro. This suggests that sTNF-R regulatory activities are pa
rtially impaired in patients with leprosy.