HIGH INTERLEUKIN-10 SERUM LEVELS ARE ASSOCIATED WITH FATAL OUTCOME INPATIENTS AFTER BONE-MARROW TRANSPLANTATION

IL-10 plays an important role in the control of immune reactions durin g systemic infection. Here, IL-10 serum levels were investigated in pa tients after BMT. The IL-10 levels correlated with the clinical course of the patients and with serum Levels of C-reactive protein (CRP) and neopterin (NP). A total of 26 patients with ARIL (7), ALL (12), CML ( 2), NHL (3) and multifocal Ewing's sarcoma (2) had received autologous (10) or allogeneic (16) BMT from related (9) or unrelated donors (7). Routine serum samples mere obtained prior to BMT and at days 46 and 1 00 after BMT. However, in patients with severe complications additiona l samples were drawn at individual points in time. Prior to BMT, LL-10 serum levels were not detectable in 24/24 patients. Post-BMT, 11 pati ents developed elevated IL-10 levels, of these eight died of complicat ions (DOG), whereas only one of 15 patients with undetectable IL-10 di ed of complications, indicating that high IL-10 levels were significan tly correlated with severe life-threatening complications (chi(Z), P < 0.01). To determine the pathomechanism and role of the increased IL-1 0 levels, they were correlated to the respective NP and CRP serum conc entrations. CRP and NP concentrations mere found significantly elevate d in patients with detectable IL-10, indicating a severe acute phase r eaction associated with macrophage activation. In conclusion, high IL- 10 serum levels in patients after BMT were significantly associated wi th fatal outcome. Since IL-10 is a strong suppressor of T cell immunit y, high IL-10 production in patients with severe complications such as septic shock or GVHD > grade II after PMT might lead to functional im munodeficiency contributing to the poor prognosis of these patients.