CPB1 and infection: Leishmania cysteine protease B (CPB) has shown promise as a VL vaccine candidate antigen in mouse and dog infection models.8, 9 Genome analyses indicated segments with significant homology of cpb with human genes, however, so to minimize any likelihood of generating anti-host responses, we deleted amino acids 1–153 of the cpb gene, generating a truncated recombinant variant of CPB (ΔCPB) devoid of potential self-reactive epitopes (Table 1).