Resposta humoral e celular em camundongos AIRmax e AIRmin tratados com crotoxina de Crotalus durissus terrificus

Abstract

Crotoxin (CTX) is the most abundant protein present in the venom of the rattlesnake Crotalus durissus terrificus (C.d.t.), being the main responsible for its toxicity. The immunomodulatory, anti-inflammatory, antitumor and analgesic action is also attributed to this toxin, presenting, therefore, great therapeutic potential. AIRmax and AIRmin mice were used as an experimental model. These strains were phenotypically selected based on maximal or minimal acute inflammatory response (AIR) intensity, but did not differ in adaptive response, producing equivalent amounts of antibodies, under the same conditions. As they are heterogeneous strains, there is great variability in the immune response and, therefore, they are a suitable model for this study. The aim of this study is to investigate the immunomodulatory effects of crotoxin on the humoral response of mice of the AIR strains. For this, AIRmax and AIRmin mice were immunized with 50 µg/mL of HGG adsorbed on aluminum hydroxide subcutaneously (s.c). At 1 h before or 72 h after immunization, a dose of crotoxin (obtained from C.d.t. rattlesnake venom) was administered intraperitoneally (i.p.). The chosen dose was 40 µg/kg of weight, whose anti-inflammatory effects can be observed. Serum was obtained every 7 days, for 28 days in order to perform the ELISA test for IgG anti-HGG detection. In conjunction with these data, splenocyte proliferation assays and cytokine (IL-2, IFN-γ) assays were carried out in order to assess whether there was cell damage. The analysis of the results obtained revealed that the treatment with crotoxin did not cause a decrease in the production of antibodies in these strains. The proliferative capacity and secretion of cytokines also did not undergo significant changes. Therefore, we consider the need to purify a new batch of crotoxin for future immunosuppression assays.