Selective lectin reactions of two stocks of Leishmania enriettii with differing pathogenicity.

Five days old promastigote culture forms of two stocks of Leishmania enriettii pathogenic and non-infective for Cavia procellus, were tested with the lectins of Canavalia ensiformis, Ricinus communis-120, Soja hispida (Glycine maxima), Arachis hypogaea, Ulex europaeus, Ulex europaeus I, Ulex europaeus II, Laburnum alpinum, Lotus tetragonolobus, Euonymus europaeus and with a monoclonal antibody against blood group H. The pathogenic stock reacted with the anti-H lectin of Lotus tetragonolobus and the monoclonal anti-H and the monoclonal anti-H but not with anti-H of U. europaeus I and E. europaeus. The non-infective stock reacted with none of these anti-H specific agglutinins. They had strong agglutination reactions to C. ensiformis (500 micrograms/ml, 1,000 micrograms/ml, 10 mg/ml) R. communis-120 (1:10), S. hispida (1,000 micrograms/ml) and A. hypogaea (500 micrograms/ml, 1,000 micrograms/ml, 2,000 micrograms/ml). They showed moderate agglutinations to U. europaeus, L. alpinum and U. europaeus II. The non-infective stock showed only moderate reactions to C. ensiformis (10 mg/ml), R. communis-120 (1:10), A. hypogaea (2,000 micrograms/ml) and S. hispida (1,000 micrograms/ml). Neither N-acetylneuraminic acid nor neuraminidase was detected on the cell surface of both stocks. This result demonstrates clearly that both stocks of L. enriettii differ in their cell surface carbohydrates. The agglutination reactions with lectins of the non-infective stock of L. enriettii are very similar to L.t. major.