CD69 and infection: Our study may also indicate that both CD103− and CD103+ subsets of CD69+ Trm-like cells produce IFN-γ and express CD107a equally well and more effectively than CD69−CD103− and CD69−CD103+ cells, suggesting an important role for CD69+ Trm-like cells in exerting the cytolytic effector function and probably successful adaptation of the immune system to fight off infections (Figure 6).