CHARACTERIZATION OF A MONOCLONAL-ANTIBODY AGAINST A 180 KDA HEMOCYTE POLYPEPTIDE INVOLVED IN CELLULAR DEFENSE REACTIONS OF THE STICK INSECTBACILLUS-ROSSIUS

Defence properties of hemoctyes were investigated using the anti-hemoc yte monoclonal antibody BrH1 obtained by immunizing mice with 2% paraf ormaldehyde-fixed hemoctyes of the stick insect Bacillus rossius, In W estern blot analysis, the antibody recognized a 180 kDa antigen in hem ocyte cell lysates, whereas fat body lysates and cell-free hemolymph w ere negative, In immunofluorescence analysis of cultured or freshly co llected hemoctyes, BrH1 stained intracellular antigen(s) in detergent- treated cells, Transverse cryosections of adult stick insects probed b y immunofluorescence with BrH1 showed in situ the scattered distributi on of hemoctyes inside the haemocoel. The antigen(s) recognized by BrH 1 appears to be involved in cell defence hemocyte-mediated mechanisms, as evidenced by the fact that cryosections of insects challenged in l ive with yeast cells, bacteria, or polystyrene lates particles and pro bed with BrH1 showed an accumulation of antigen surrounding the inject ed stimuli. (C) 1997 Elsevier Science Ltd.