Haemagglutinating and microfilaricidal factors in haemolymph of Brugia pahagi-infected Armigeres subalbatus

Abstract

It is not uncommon to see dead parasites in the haemocoels of insects and the production of toxic factors associated with 'immune' response have been demonstrated by many workers. In this communication, we demonstrate the presence of haemaglutinins and also microfilaricial factors in the haemolymph of Brugia pahangi-infected Armigeres subalbatus. Maximum haemagglutinating activity was observed at 24 hours post infection (p.i) followed by day 6 p.i. Similarly, peak microfilaricidal activity was in the haemolymph obtained from mosquitoes with a 24 hour old infection and the effect was minimal in the mosquitoes dissected on day 6 or day 10 p.i. The mosquitoes seemed to mount a significant response only during the early stages of infection i.e. when the microfilariae were in the haemocoel and when stage 2 larvae moult into stage-3 in the thorax.