RESUMO
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.
Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos CD/análise , Apirase/análise , Leishmania braziliensis/enzimologia , Animais , Anticorpos Imobilizados/imunologia , Antígenos CD/imunologia , Apirase/antagonistas & inibidores , Apirase/imunologia , Western Blotting , Imunoprecipitação , Isoenzimas/análise , Isoenzimas/imunologia , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Imunoeletrônica , CoelhosRESUMO
In this paper, we showed for the first time that the conserved domains within Schistosoma mansoni ATP diphosphohydrolase isoforms, shared with potato apyrase, possess epitopes for the IgG1 and IgG4 subtypes, as 24 (80%) of the 30 schistosomiasis patients were seropositive for this vegetable protein. The analyses for each patient cured (n = 14) after treatment (AT) with praziquantel revealed variable IgG1 and IgG4 reactivity against potato apyrase. Different antigenic epitopes shared between the vegetable and parasite proteins could be involved in susceptibility or resistance to S. mansoni AT with praziquantel and these possibilities should be explored.
Assuntos
Anticorpos Anti-Helmínticos/imunologia , Apirase/imunologia , Imunoglobulina G/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Solanum tuberosum/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anti-Helmínticos/uso terapêutico , Criança , Pré-Escolar , Reações Cruzadas , Humanos , Pessoa de Meia-Idade , Praziquantel/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Adulto JovemRESUMO
In this paper, we showed for the first time that the conserved domains within Schistosoma mansoni ATP diphosphohydrolase isoforms, shared with potato apyrase, possess epitopes for the IgG1 and IgG4 subtypes, as 24 (80 percent) of the 30 schistosomiasis patients were seropositive for this vegetable protein. The analyses for each patient cured (n = 14) after treatment (AT) with praziquantel revealed variable IgG1 and IgG4 reactivity against potato apyrase. Different antigenic epitopes shared between the vegetable and parasite proteins could be involved in susceptibility or resistance to S. mansoni AT with praziquantel and these possibilities should be explored.