In our study, IFN-γ production (Fig. 1b) and CD4+ memory T cell expansion (Fig. 1c) were observed in spleen and lung cells isolated from mice treated with HSP70 and GrpE at various time points after infection with Mtb K, indicating that both antigens are recognised by the host immune system as immunogenic antigens. This evidence concerns the gene GRPEL1 and infection.