RELATIONSHIPS BETWEEN CELL-SURFACE PROTEASE AND ACID-PHOSPHATASE ACTIVITIES OF LEISHMANIA PROMASTIGOTE

A correlation between the ratio of the cell surface protease activity to phosphatase activity and the complexity of the pattern of cell surf ace exposed polypeptides of Leishmania promastigotes was demonstrated for various strains grown under similar conditions. The ratio of the c ell surface protease activity to acid phosphatase activity was high fo r L. major and L.b. panamensis and it correlates with the expression o f a single polypeptide of 63 kDa on their cell surface. Intermediate a nd lower ratios of these enzymatic activities relate with more complex radio-iodinated patterns: two main bands in L.b. guyanensis (70 and 5 8 KDa) and L.b. braziliensis (72 and 60 KDa) and three main bands 65, 50, 27 KDa in all L.m. mexicana strains tested. Evidence is presented that the acid phosphatase located on the L.m. mexicana cell surface is not an artifact due to a secondary absorption of the secreted acid ph osphatase from the culture medium. These results confirm the Leishmani a antigen cell surface heterogeneity. The implication on the biology o f Leishmania and the clinical manifestation of leishmaniasis are discu ssed.