TIGIT axis: novel immune checkpoints in anti-leukemia immunity.

Hematologic malignancy evades immune-mediated recognition through upregulating various checkpoint inhibitory receptors (IRs) on several types of lymphocytes. Immunotherapies targeting IRs have provided ample evidence supporting regulating innate and adaptive immunity and obtaining clinical benefits. Newly described IRs have received considerable attention and are under investigation in cancer immunotherapy. Specifically, T cell immunoglobulin and ITIM domain is a novel inhibitory checkpoint receptor, and its immune checkpoint axis includes additional receptors such as CD96 and CD226, which are very promising targets. However, how the dynamics and functions of these receptor networks remain unknown, this review addresses the recent findings of the relevance of this complex receptor-ligand system and discusses their potential approaches in translating these preclinical findings into novel clinical agents in anti-leukemia immunotherapy.