title: The effect of lectins on Cryptosporidium parvum oocyst in vitro attachment to host cells.
abstract: The influence of lectins on Cryptosporidium parvum oocyst agglutination and on attachment to both fixed Madin Darby Canine Kidney (MDCK) cells and fixed HCT-8 (human colorectal epithelial) cells was examined. Oocyst cell wall characteristics were examined by transmission electron microscopy. Lectin-free oocysts were shown to adhere equally to both MDCK cells and HCT-8 cells. In MDCK cells, the addition of 1-25 microg/ml Codium fragile lectin, 10 microg/ml Maclura pomifera lectin, 10 microg/ml Helix pomatia lectin, and 10-200 microg/ml Artocarpus integrifolia lectin significantly increased attachment to at least 1 of the cell cultures as compared to oocysts incubated without any lectin. The lectin-enhanced attachment was reversed by co-incubation of lectin treated-oocysts with 250 mM of each specific sugar (for a given lectin). In agglutination assays, concentrations as low as 0.5 microg/ml of C. fragile, M. pomifera, and A. integrifolia lectin agglutinated oocysts within 60 min. Finally, in TEM samples, colloidal gold conjugated-lectins from A. integrifolia, C. fragile, H. pomatia, and M. pomifera attached to oocysts, and this could be competitively inhibited by a lectin-specific sugar. This suggests that C. parvum oocysts are highly reactive to N-acetyl galactosamine-binding lectins and that the presence of N-acetyl-galactosamine containing molecules on oocysts can potentially help in oocyst attachment to host cells.
authors.affiliation: Indiana University Kokomo, 2300 South Washington Street, Kokomo, Indiana 46904-9003, USA.
authors.forename: Barry
authors.initials: B
authors.lastname: Stein
authors.forename: Larry
authors.initials: L
authors.lastname: Stover
authors.forename: Ashley
authors.initials: A
authors.lastname: Gillem
authors.forename: Katherine
authors.initials: K
authors.lastname: Winters
authors.forename: John H
authors.initials: JH
authors.lastname: Leet
authors.forename: Christian
authors.initials: C
authors.lastname: Chauret
mesh_terms: D000371:Agglutination / Q000187:drug effects; D000372:Agglutination Tests / Q000379:methods; D000818:Animals; D050260:Carbohydrate Metabolism; D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D016785:Cryptosporidium parvum / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D004285:Dogs; D006031:Glycosylation / Q000187:drug effects; D017979:Gold Colloid / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D046529:Microscopy, Electron, Transmission / Q000379:methods; D033661:Oocysts / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D017979:Gold Colloid; D037102:Lectins