We first leveraged a study of 26 granulomas from four cynomolgus macaques assessed at 10 weeks after low-dose infection with Mtb (<10 colony forming units (c.f.u.)) using single-cell RNA sequencing (RNA-seq)32 in which several T cell clusters, including GZMB+S100A10+ cytotoxic, MKI67+ proliferating, CCR7+TCF7+ stem-like and TXNIP+CCR6+ T1–T17 cell populations, were associated with reduced bacterial burden32. Here, GZMB is linked to infection.