Although no significant differences were found in the frequency of CD4+Foxp3+ T cells between all groups evaluated at the beginning of infection (2 and 6 weeks post-infection), we found that the oral administration of Hsp65-producing L. lactis increased the frequency of CD4+Foxp3+ (at 10 weeks of infection) in cultures of draining lymph node cells, indicating that regulatory T cells may be involved in mitigating the inflammation caused by L. braziliensis. This evidence concerns the gene CD4 and infection.