TIGIT and myelodysplastic syndrome: T-cells in the immunosuppressive BMME of AML and high-risk MDS patients with markedly deregulated innate and adaptive immune responses are characterized by a phenotype of “exhaustion” with augmented expression of PD-1, T cell immunoglobulin and ITIM domain (TIGIT), and T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) antigens as well as functional cytotoxic T-cell (CTL) deficiency (Brauneck et al., 2021; Goswami et al., 2016; Ladikou et al., 2020; Jia et al., 2018).