THE EFFECT OF LECTINS ON CRYPTOSPORIDIUM PARVUM OOCYST IN VITRO ATTACHMENT TO HOST CELLS

• Published in: The Journal of parasitology 2006-02, Vol.92 (1), p.1-9
• Main Authors: Stein, Barry, Stover, Larry, Gillem, Ashley, Winters, Katherine, Lee, John H, Chauret, Christian
• Format: Article
• Language: English
• Subjects: Agglutination; Agglutination - drug effects; Agglutination Tests - methods; Agglutinins; Animals; Artocarpus integrifolia; Attachment; Biological and medical sciences; Carbohydrate Metabolism; Carbohydrates; Cell Adhesion - drug effects; Cell culture; Cell Line, Tumor; Cell walls; Codium fragile; Cryptosporidium; Cryptosporidium parvum; Cryptosporidium parvum - drug effects; Cryptosporidium parvum - physiology; Cryptosporidium parvum - ultrastructure; D-Galactosamine; Development; Dogs; Epithelial cells; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Glycoproteins; Glycosylation - drug effects; Gold Colloid - metabolism; Gold collolid; Helix pomatia; Humans; Infections; Invertebrates; Laboratories; Lectins; Lectins - metabolism; Lectins - pharmacology; Maclura pomifera; Mammals; Mice; Mice, Inbred BALB C; Microscopy; Microscopy, Electron, Transmission - methods; N-Acetylgalactosamine; Oocysts; Oocysts - drug effects; Oocysts - physiology; Oocysts - ultrastructure; Parasite hosts; Parasites; Proteins; Protozoa; Sporozoites; Sugar; Sugars; Time Factors; Transmission electron microscopy
• ISSN: 0022-3395; 1937-2345
• DOI: 10.1645/GE-570R.1

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 μg/ml Codium fragile lectin, 10 μg/ml Maclura pomifera lectin, 10 μg/ml Helix pomatia lectin, and 10–200 μg/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 μg/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.