Binding of Lectins to Culture and Vector Forms of Trypanosoma rangeli Tejera, 1920 (Protozoa, Kinetoplastida) and to Structures of the Vector Gut

Abstract

Culture forms of Trypanosoma rangeli could be agglutinated with Canavalia ensiformis (Con A) lectin and, less effectively with Pisum sativum agglutinin (PEA), at a concentration of 200 micrograms/ml. Ricinus communis agglutinin I (RCA I) agglutinated trypanosomes only if they were not previously washed with physiological Ringer's solution. Three other lectins did not react with the same parasite forms. Direct or indirect lectin-gold labeling techniques were applied to LR-White embedded thin sections of T. rangeli culture forms and to forms in the gut, hemolymph, and salivary glands of Rhodnius prolixus. Under these conditions, Con A was the only lectin out of 9 that bound to the surface of trypanosomes from culture and from the bug hemolymph. Con A did not react with any midgut or salivary gland forms. The preservation of the biological activity of the lectin-gold complexes that did not bind to the parasite surface was confirmed by reactions with structures of the invertebrate host.

Revisión de los aspectos biológicos y diagnósticos del Trypanosoma (Herpetosoma) rangeli

“…Importante campo de estudios ha sido también el uso de lectinas, como marcadores de la composición de los resíduos de azúcares en la superficie de T. rangeli 42 58 . Observaciones con ConA y PEA (Pisum sativum) hechas con formas de cultivo, de la hemolinfa y también, en los tejidos de los insectos infectados, sugieren que, las variaciones de esos azúcares en la superficie del tripanosoma permitirían explicar por qué algunas cepas de T. rangeli, se adaptan mejor a algunas especies de triatominos y son más propicias para evolucionar en los insectos, que otras 51 . Significativo aporte ha surgido ultimamente del arsenal de herramientas de la biología molecular 49 62 Tanaka et al 64 y Henrikson et al 30 en sus estudios de kariotipaje molecular de T. rangeli, usando el sistema de Pulse Field Gel Electrophoresis, PFGE e hibridización con diversas sondas moleculares, fueron capaces de identificar bandas cromosómicas específicas de T. rangeli, que permitirían clara distinción con las de T. cruzi.…”

Involvement of Trichomonas vaginalis surface-associated glycoconjugates in the parasite/target cell interaction. A quantitative electron microscopy study

“…According to several studies (Horisberger 1984;Benhamou and Ouellette 1986;Morioka et al 1987;Rudin et al 1989), thin sections of various pathogenic agents can be labeled with gold particle-conjugated lectins. Mannose was found in the cell walls and in some vacuoles after labeling of thin sections of Candida utilis with gold particle-conjugated Con A (Horisberger 1984).…”

“…Morioka et al (1987) reported the labeling of thin sections of Escherichia coli with WGA-gold complex. Rudin et al (1989) labeled thin sections of two Although we employed several methods (chemical ®xation of T. vaginalis cells, thermal polymerisation of resin and the freeze-substitution technique, UV polymerisation of resin) to prepare T. vaginalis cells for electron microscopy, no label was observed after exposure of thin sections of T. vaginalis to various gold particle-conjugated lectins (Figs. 2, 3).…”