title: SHP-2 Mediates Cryptosporidium parvum Infectivity in Human Intestinal Epithelial Cells.
abstract: The parasite, Cryptosporidium parvum, induces human gastroenteritis through infection of host epithelial cells in the small intestine. During the initial stage of infection, C. parvum is reported to engage host mechanisms at the host cell-parasite interface to form a parasitophorous vacuole. We determined that upon infection, the larger molecular weight proteins in human small intestinal epithelial host cells (FHs 74 Int) appeared to globally undergo tyrosine dephosphorylation. In parallel, expression of the cytoplasmic protein tyrosine phosphatase Src homology-2 domain-containing phosphatase 2 (SHP-2) increased in a time-dependent manner. SHP-2 co-localized with the C. parvum sporozoite and this interaction increased the rate of C. parvum infectivity through SH2-mediated SHP-2 activity. Furthermore, we show that one potential target that SHP-2 acts upon is the focal adhesion protein, paxillin, which undergoes moderate dephosphorylation following infection, with inhibition of SHP-2 rescuing paxillin phosphorylation. Importantly, treatment with an inhibitor to SHP-2 and with an inhibitor to paxillin and Src family kinases, effectively decreased the multiplicity of C. parvum infection in a dose-dependent manner. Thus, our study reveals an important role for SHP-2 in the pathogenesis of C. parvum. Furthermore, while host proteins can be recruited to participate in the development of the electron dense band at the host cell-parasite interface, our study implies for the first time that SHP-2 appears to be recruited by the C. parvum sporozoite to regulate infectivity. Taken together, these findings suggest that SHP-2 and its down-stream target paxillin could serve as targets for intervention.
authors.affiliation: Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America.|National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, Ohio, United States of America.
authors.forename: Eunice A
authors.initials: EA
authors.lastname: Varughese
authors.affiliation: Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America.
authors.forename: Susan
authors.initials: S
authors.lastname: Kasper
authors.affiliation: National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, Ohio, United States of America.
authors.forename: Emily M
authors.initials: EM
authors.lastname: Anneken
authors.affiliation: Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America.
authors.forename: Jagjit S
authors.initials: JS
authors.lastname: Yadav
mesh_terms: D000818:Animals; D002460:Cell Line; D003457:Cryptosporidiosis / Q000209:etiology / Q000378:metabolism / Q000469:parasitology; D016785:Cryptosporidium parvum / Q000378:metabolism / Q000472:pathogenicity*; D006790:Host-Parasite Interactions / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000469:parasitology*; D051379:Mice; D051419:Paxillin / Q000037:antagonists & inhibitors / Q000378:metabolism; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D034101:Sporozoites / Q000378:metabolism; D014774:Virulence / Q000187:drug effects / Q000502:physiology; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: C496061:PXN protein, human; D051419:Paxillin; D019061:src-Family Kinases; C516724:PTPN11 protein, human; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11