Updated project metadata. Male CD-1 mice (N=8) were intraperitoneally infected by culture-derived Trypanosoma cruzi trypomastigotes of the Brazil strain. One group (N=4) was treated with an antitrypanosomal drug (nifurtimox) on day 74 post-infection (chronic phase) for 20 days. A group of uninfected mice (N=3) was also included as control. All groups (N=11) were enthanized on day 110 post-infection, testes were collected and subjected to 2D-LC-MS/MS analysis. Label-free quantitation revealed that the testes of T. cruzi-infected mice had an altered proteome pattern relative to treated mice and uninfected controls. The analysis also demonstrated that the left and right testes had different proteomic profiles in infected animals.