The infection of murine macrophages and fibroblasts by recently isolated infective bloodstream trypomastigotes of Trypanosoma cruzi is inhibited by the addition of human plasma protease inhibitor alpha-2-macroglobulin (alpha 2M) or of soybean trypsin inhibitor. The ingestion of the non-infective epimastigotes by macrophages is not affected by the physiological protease inhibitor. Incubation of bloodstream trypomastigotes for 20 h in a serum-free axenic medium enhances their ability to infect macrophages in a process influenced by the temperature and sensitive to alpha 2M. After this period the infectivity of the parasites to cells was not sensitive to alpha 2M. These observations suggest that proteases located on the surface and/or secreted by the bloodstream trypomastigote form of T. cruzi may modulate its ability to infect host cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.