[Increased oxidative metabolism of alveolar macrophages in idiopathic fibrosing alveolitis].

The results of the present investigation show that, in IPF, alveolar macrophages are preactivated, and are capable, both spontaneously and also after cellular stimulation with a variety of stimulants, of producing appreciably more cytotoxic oxygen metabolites as compared with alveolar macrophages from healthy control subjects. A striking finding is the fact that the production of oxidants following stimulation with the complement factors C3a-C5a and aggregated IgG is appreciably lower than following stimulation with PMA or zymosan. This might be evidence in support of the theory that the alveolar macrophages in IPF are activated by immune complexes.