Schistosoma mansoni: excretion of circulating anodic antigen (CAA) during in vitro culture
Rotmans, J.P.; Burgers, A.
Acta Leidensia 56: 15-26
1987
ISSN/ISBN: 0065-1362 PMID: 3450116 Document Number: 289685
Adult Schistosoma mansoni were maintained in serum-free medium RPMI-1640. During the course of cultivation, the amounts of antigen excreted, and the antigen content of the worms were determined by a sandwich enzyme-linked immunosorbent assay, using hyperimmune sera directed against circulating anodic antigen (CAA) and excretory and secretory antigens (ESA) in general. Compared to the amounts of antigen, present in the worms at the start of the cultivation, the proportion of excreted CAA was much less than the proportion of ESA. Moreover, CAA excretion stopped when the cultivation medium was replaced with fresh serum free medium. Addition of 20% fetal calf serum greatly stimulated the excretion of CAA and prevented the cessation of CAA excretion which occurred after replacement with serum free medium. During cultivation in serum supplemented medium, an increase in ESA content of the worms and a decrease in CAA content were observed. The results of this study clearly indicate that CAA synthesis and excretion are very susceptable to changes in the environment.