Circulating TNF-alpha, TGF-beta, and IL-10 in tuberculosis patients and healthy contacts

Levels of tumour necrosis factor (TNF)-alpha, transforming growth factor (T GF)-beta, and interleukin (IL)-10 in plasma of pulmonary tuberculosis (TB) patients and healthy contacts and plasma and pleural fluid of patients with tuberculous pleuritis were examined by enzyme immunoassay. Plasma TNF-alph a and IL-10 were elevated to significant levels in healthy contacts, High l evels of TGF-beta and IL-10 were also detected in plasma from TB patients a nd healthy contacts. Pleural fluid contained all three cytokines with the l evel of IL-10 being highest followed by TGF-beta and TNF-alpha. Plasma of t uberculous pleuritis patients also had detectable levels of the three cytok ines. Increased levels of TNF-alpha in plasma of contacts and to some exten t pleural fluid of pleuritis patients, is perhaps to limit the infection, w hile elevated IL-10 in plasma of TB patients and contacts and pleural fluid would perhaps modulate excess proinflammation. Elevated TGF-beta in TB pat ients suggests its role in the immunopathogenesis.