title: Immunomodulatory effects of crotoxin isolated from Crotalus durissus terrificus venom in mice immunised with human serum albumin.
abstract: Crotalus durissus terrificus venom and its main component, crotoxin (CTX), have the ability to down-modulate the immune system. Certain mechanisms mediated by cells and soluble factors of the immune system are responsible for the elimination of pathogenic molecules to ensure the specific protection against subsequent antigen contact. Accordingly, we evaluated the immunomodulatory effects of CTX on the immune response of mice that had been previously primed by immunisation with human serum albumin (HSA). CTX inoculation after HSA immunisation, along with complete Freund's adjuvant (CFA) or Aluminium hydroxide (Alum) immunisation, was able to suppress anti-HSA IgG1 and IgG2a antibody production. We showed that the inhibitory effects of this toxin are not mediated by necrosis or apoptosis of any lymphoid cell population. Lower proliferation of T lymphocytes from mice immunised with HSA/CFA or HSA/Alum that received the toxin was observed in comparison to the mice that were only immunised. In conclusion, CTX is able to exert potent inhibitory effects on humoral and cellular responses induced by HSA immunisation, even when injected after an innate immune response has been initiated.
authors.affiliation: Laboratório de Imunopatologia, Instituto Butantan, Av Vital Brasil, 1500, Butantã, CEP 05503-900, São Paulo, Brazil. brunafavoretto@hotmail.com
authors.forename: B C
authors.initials: BC
authors.lastname: Favoretto
authors.forename: R
authors.initials: R
authors.lastname: Ricardi
authors.forename: S R
authors.initials: SR
authors.lastname: Silva
authors.forename: J F
authors.initials: JF
authors.lastname: Jacysyn
authors.forename: I
authors.initials: I
authors.lastname: Fernandes
authors.forename: H A
authors.initials: HA
authors.lastname: Takehara
authors.forename: E L
authors.initials: EL
authors.lastname: Faquim-Mauro
mesh_terms: D056704:Adaptive Immunity / Q000187:drug effects* / Q000276:immunology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003435:Crotalid Venoms / Q000276:immunology*; D003439:Crotoxin / Q000633:toxicity*; D006801:Humans; D008198:Lymph Nodes / Q000187:drug effects / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009336:Necrosis / Q000139:chemically induced; D012709:Serum Albumin / Q000009:adverse effects* / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000473:pathology
chemical_list: D003435:Crotalid Venoms; D012709:Serum Albumin; D003439:Crotoxin