title: Potential immunomodulatory effects of plant lectins in Schistosoma mansoni infection.
abstract: Lectins are sugar-binding glycoproteins that can stimulate, in a non-antigen-specific fashion, lymphocytes, leading to proliferation and cytokine production. Some lectins are utilized as in vitro mitogenic lymphocyte stimulators and their use as immunomodulators against infectious diseases has been evaluated experimentally. In the experimental murine model, the immune response to schistosomiasis is Th1-like during the initial stage of infection, with a shift towards a Th2-like response after oviposition. We report the response of schistosomiasis patients' (n=37) peripheral blood mononuclear cells (PBMC) to stimulation by lectins, including newly isolated lectins from Brazilian flora, and by Schistosomamansoni soluble egg antigens (SEA). Cytokine production upon lectin stimulation ex vivo was assessed in PBMC supernatants, collected at 24 and 72 h, by sandwich ELISA to IL-5, IL-10, TNF-alpha and IFN-gamma. In PBMC from infected patients all but one of the lectins induced a Th2-like cytokine response, characterized by elevated IL-5 production that was higher than that induced by SEA stimulation alone. Our results show that the Th2 environment present during schistosomiasis is not affected and that it may be further stimulated by the presence of lectins.
authors.affiliation: Fundação Oswaldo Cruz (FIOCRUZ), Bahia, Brazil.
authors.forename: Eliana A G
authors.initials: EA
authors.lastname: Reis
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Athanazio
authors.forename: Benildo Sousa
authors.initials: BS
authors.lastname: Cavada
authors.forename: Edson Holanda
authors.initials: EH
authors.lastname: Teixeira
authors.forename: Vicente
authors.initials: V
authors.lastname: de Paulo Teixeira Pinto
authors.forename: Theomira M A
authors.initials: TM
authors.lastname: Carmo
authors.forename: Alice
authors.initials: A
authors.lastname: Reis
authors.forename: Graziela
authors.initials: G
authors.lastname: Trocolli
authors.forename: Julio
authors.initials: J
authors.lastname: Croda
authors.forename: Donald
authors.initials: D
authors.lastname: Harn
authors.forename: Manoel
authors.initials: M
authors.lastname: Barral-Netto
authors.forename: Mitermayer G
authors.initials: MG
authors.lastname: Reis
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002478:Cells, Cultured; D002648:Child; D016207:Cytokines / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology*; D037102:Lectins / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012555:Schistosomiasis mansoni / Q000276:immunology*
chemical_list: D016207:Cytokines; D007155:Immunologic Factors; D037102:Lectins