LOCALIZATION OF THE A1.12 9 ANTIGEN FAMILY TO THE NEURONS, PUTATIVE SENSORY RECEPTORS AND TEGUMENT OF SCHISTOSOMA-MANSONI/

The A1.12/9 antigen family were localized to the periphery of vesicle- like structures in neurones and in the putative sensory receptors of c ercariae by immuno-electron microscopy. After transformation into schi stosomula, the antigens were rapidly lost until, after 18 h, no immuno reactivity could be detected. Expression resumed at approximately 36 h post-transformation and had returned to high levels by 4 days post-in fection. This level was maintained through to the adult worm stage. In 4 day lung schistosomula and in 14 day and 21-day liver schistosomula immunolabelling was observed within the matrix of the tegument itself and also in association with the tegumental membrane and vesicles wit hin the tegument. These properties suggest that the A1.12/9 antigens m ay be involved in neuropeptide processing pathways. In particular, thi s family may represent the schistosome homologue of the granin family with which they share common properties and some sequence homology.