GZMB and HIV-1 infection: Our findings also showed a higher concentration of granzyme B in the supernatants of the co-cultures of HR-MSM, with a tendency to higher levels of TNF-α and IFN-γ, which could be linked to differences in the percentages of p24+ CD4+T cells observed, suggesting that granzyme B could be an important natural resistance mechanism to HIV-1 infection.