Abstract

Pigeon fanciers' lung is an immunologically-mediated lung disease as a result of inhaling pigeon derived materials. High antibody titres are observed for symptomatic and asymptomatic pigeon fanciers. The aim of the present study was to investigate whether immune complexes from individuals with pigeon fanciers’ lung were better at activating macrophages than immune complexes from asymptomatic pigeon fanciers. Serum samples were obtained from fifteen individuals with pigeon fanciers’ lung, fifteen asymptomatic pigeon fanciers and fifteen non-farming controls. Solid immune complexes were generated with these serum samples with the pigeon derived antigen mucin. The immune complexes were then incubated with macrophage U937 cells. The supernatants of the cell culture were thereafter analysed for tumour necrosis factor-a (TNF-a), interleukin 6 (IL 6), interleukin 1 (IL 1), nitric oxide and catalase as indices for the activation of macrophages. The activation by lipopolysaccharide was used as a positive control. The results showed that the immune complexes from symptomatic pigeon fanciers activated macrophages significantly better than immune complexes from asymptomatic pigeon fanciers (P < 0.05). Immune complexes from non-farming controls exhibited the least propensity in activating the macrophages. The findings suggest that immune complex activation of macrophages could be used to assign farmers to been symptomatic and asymptomatic.

Key words: Pigeon fanciers’ lung, macrophages, activation, immune complexes, mucin.