Characterisation of a monoclonal antibody recognising specifically the HSP70 from Leishmania

Heat-shock protein 70 (HSP70) is ubiquitously distributed along the evolutionary scale and has such an amino acid sequence conservation that it is considered the most evolutionarily conserved protein. In order to obtain immunological tools specific against Leishmania infantum HSP70, hybridomas were established that secreted monoclonal antibodies (mAbs) against recombinant L. infantum HSP70. One of them, named mAb 2B8D2, specifically reacted with the Leishmania protein and did not recognise HSP70 from the related kinetoplastid Trypanosoma cruzi. The use of synthetic peptides allowed us to determine the B-cell epitope recognised by this mAb, an epitope located in the divergent C-terminal domain of the protein. Remarkably, the mAb possesses the capacity to immunoprecipate HSP70 from promastigote extracts of L. infantum. The fact that human HSP70 is not recognised by this mAb assures the usefulness of this antibody for diagnostic purposes and studies involving Leishmania infection of macrophages.