Tumour necrosis factor in hepatosplenic schistosomiasis.

Periportal fibroplasia is the dominating feature of hepatosplenic schistosomiasis. Since monokines play an important role in the regulation of fibroplasia, tumour necrosis factor (TNF) and interleukin 1 beta (IL-1 beta) were assessed in sera and cell culture supernatants from patients with intestinal and hepatosplenic schistosomiasis before and 3-6 months after treatment with praziquantel. Uninfected controls were from the study area in Alagoas, Brazil. TNF was measured using an L-M mouse fibroblast bioassay and radioimmunoassays specific for TNF-alpha. Whereas TNF-alpha was elevated threefold in the patients' sera, three- to five-fold reductions of TNF were observed by radioimmunoassay and bioassay, respectively, in cell culture supernatants of hepatosplenic schistosomiasis patients. Significant deviations, in opposite directions, from TNF levels in control sera and supernatants are most plausible in the event of a sequestration of TNF-alpha-producing cells from the circulation. This process may be disease stage-specific since a dichotomy between incipient and advanced cases of hepatosplenic schistosomiasis became apparent in the amplitude and kinetics of changes during the follow-up after treatment.