SERUM LEVELS OF SOLUBLE FAS APO-1 RECEPTOR IN HUMAN RETROVIRAL INFECTION AND ASSOCIATED DISEASES/

Fas/APO-1 mediates apoptosis via Fas and Fas ligand transduction, Rece ntly, a soluble form of Fas (sFas) was described which seems to be fun ctionally implicated in the Fas signal system, suggesting a relationsh ip between some disorders and sFas function, We measured sFas-levels i n sera from normal controls and patients with disorders linked to huma n retroviral infection of human immunodeficiency virus (HIV) and human T-cell leukemia virus type-1 (HTLV-1), The sFas level of normal contr ols, HTLV-1 carriers seronegative for HIV, and patients with HTLV-1 as sociated myelopathy/tropical paraparesis (HAM/TSP), adult T-cell leuke mia (ATL), and AIDS was 1.62+/-0.49, 1.90+/-0.49, 2.00+/-0.59, 3.32+/- 2.05, and 3.06+/-0.92 ng/ml, respectively, Although the level of sFas in patient groups with HAM/TSP, ATL, and AIDS was significantly high i n comparison to that of normal controls (p<0.01), the individual value s were highly variable within the groups, The sFas level was statistic ally correlated to the soluble interleukin-2 receptor (sIL-2R) level, as well as to cells expressing membrane Fas (mFas), indicating the sam e cellular origin, In some ATL cases, however, serum sFas levels and m Fas expression density on leukemic T-cells were discrepant, with espec ially high levels of the soluble form and a lack of expression of the membrane form observed in 2 cases, sFas detection could serve as a put ative marker for active diseases in patients with ATL and AIDS.