ACTA TROPICA ELSEVIER Acta Tropica 68 (1997) 23-35 Detection of lectin activity in Leishmania promastigotes and amastigotes Milena Svobodová a,*, Paul A. Bates b, Petr Volfa / a Department oj' Parasitology, Faculty oj' Science, Charles University, Vinicná 7, 12844 Prague, Czech Republic b Liverpool School oj' Tropical Medicine, Pembroke Place, Liverpool L3 5QA UK Received 20 September 1996; received in revised form 21 March 1997; accepted 20 April 1997 Abstract Celllysates [rom 16 strains o[ eight Leishmania species were used to test haemagglutina- tion activity (HA) against a variety o[ RBC. HA was detected using native or neuraminidase- treated rabbit RBC; it was [ound in promastigotes o[ all the Leishmania strains tested and in axenic amastigotes o[ L. mexicana. The HA was trypsin-sensitive, heat-resistant and partially dependent on divalent cations. The HA was inhibited by amino-sugars, LPS [rom E. coli K 235, [etuin and heparin. The HA is probably located on the sur[ace o[ promastigotes, as shown by the same sugar-binding specificity when live cells were used in inhibition tests. Leishmania promastigotes were agglutinated with neoglycoproteins NAc-glc-BSA and NAc- gal-BSA. This agglutination was blocked by galactosamine, glucosamine and sialic acid, blit not by glcNAc or galNAc. The level o[ HA is increased in axenic amastigotes when compared to promastigotes. In general, HA was [ound at a higher litre in in[ective compared to unin[ective strains o[ Leishmania. These results suggest lhal the haemagglutinin could play a role in the vertebrate phase o[ the parasite li[e cycle, possibly in macrophage attachment or invasion. @ 1997 Elsevier Science B.V. Keywords: Leishmania; Amastigotes; Lectin activity; Li[e cycle * Corresponding author. Fax.: + 42 2 299713; e-mail: volf@beba.cesnet.cz 0001-706Xj97j$17.00 @ 1997 EIsevier Science B.V. AU rights reserved. PIl SOOO1-706X(97)00069- 7