Leishmania (Viannia) braziliensis nucleoside triphosphate diphosphohydrolase (NTPDase 1): Localization and in vitro inhibition of promastigotes growth by polyclonal antibodies

Nucleoside triphosphate diphosphohydrolase (NTPDase) activity was recently characterized in Leishmania (Viannia) braziliensis promastigotes (Lb), and an antigenic conserved domain (r82-121) from the specific NTPDase 1 isoform was identified. in this work, mouse polyclonal antibodies produced against two synthetic peptides derived from this domain (LbB1LJ, r82-103; LbB2LJ, r102-121) were used. the anti-LbB1LJ or anti-LbB2LJ antibodies were immobilized on protein A-sepharose and immunoprecipitated the NTPDase 1 of 48 kDa and depleted approximately 40% of the phosphohydrolytic activity from detergent-homogenized Lb preparation. Ultrastructural immunocytochemical microscopy identified the NTPDase 1 on the parasite surface and in its subcellular cytoplasmic vesicles, mitochondria, kinetoplast and nucleus. the ATPase and ADPase activities of detergent-homogenized Lb preparation were partially inhibited by anti-LbB1LJ antibody (43-79%), which was more effective than that inhibition (18-47%) by anti-LbB2LJ antibody. in addition, the immune serum anti-LbB1LJ (67%) or anti-LbB2LJ (33%) was cytotoxic, significantly reducing the promastigotes growth in vitro. the results appoint the conserved domain from the L braziliensis NTPDase as an important target for inhibitor design and the potential application of these biomolecules in experimental protocols of disease control. (c) 2012 Elsevier Inc. All rights reserved. ; Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) ; PROQUALI/UFJF ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Univ Fed Juiz de Fora, Inst Ciencias Biol, Dept Bioquim, BR-36036900 Juiz de Fora, MG, Brazil ; Univ Fed Alfenas, Inst Ciencias Biomed, Dept Ciencias Biol, Alfenas, MG, Brazil ; Fiocruz MS, Inst Oswaldo Cruz, Lab Biol Estrut, Rio de Janeiro, RJ, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Biofis, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Biofis, São Paulo, Brazil ; FAPEMIG: CBB-APQ-01384-09 ...