Autor: CASTANHEIRA, P

Orientador: CHAVEZ-OLORTEGUI, C

Outros autores: BOHORQUEZ, K; MARTINS, M S; GRANIER, C;;

Linhas de pesquisa no CNPq: IMUNOLOGIA / IMUNMOQUIMICA

Unidade: INSTITUTO DE CIÊNCIAS BIOLÓGICAS
Departamento: BIOQUIMICA E IMUNOLOGIA

Palavras-Chave: PEPTIDEOS SINTETICOS, SPOT-SINTESE, PHAGE DISPLAY - -

Local or evasive hemorrhage is a major complication resulting from envenomation by Bothrops and Lachesis snake venoms. Mutalysin-II is a 22.5 kDa single chain protein, purified from the Lachesis venom with broad substrate specificity and hemorrhagic effects. We have shown previously that polyclonal antibodies and a monoclonal antibody against Mutalysin show cross-reactivy and neutralize the hemorrhagic effects of some Bothrops and Lachesis whole venoms. These results suggest that Mutalysin-II is a very efficient antigen, which might have potential for the preparation of efficient anti-venom antisera for passive immunotherapy or even for human vaccination. Two different approaches, the phage display technique and the Spot peptide synthesis on cellulose membranes, were used to identify sequences recognized by specific antibodies against Mutalysyn-II, and define the preferred chemical composition of functional epitopes. Our results show that the functional epitope of noclonal and policlonal antibodies derived from the complete aminoacid sequence of mutalisyn and identified by Spot synthesis methods requires precise physico-chemical properties at a limited number of positions, and that residues flanking these key residues can influence binding affinity. However, the phage display method localize functional epitopes no related with the aminoacid sequence. The results obtained in the present study indicate that the phage display and Spot synthesis methods should be used as technique for the precise localization of conformational and linear funceional epitopes, respectively.

Apoio: CNPq, FAPEMIG, INSERM-FRANCEp>