Phenotypic and functional alterations of innate lymphoid cells in hematological malignancies: potential clinical application

Innate lymphoid cells are lymphocytes that are neither T cells nor B cells. They are relatively rare in lymphoid tissues and peripheral blood and are distinguished by their absence of an adaptive antigen receptor. In the present study, we describe the mechanisms underlying the generation of the various cell populations and highlight the functional importance of their plasticity. These cells are indeed capable of transdifferentiating from one type to another. This adds complexity to their functional program, and this feature appears to be crucial for adapting and modulating immune responses under different conditions. These lymphoid cells are of great hematological interest due to their pathophysiological and therapeutic role in many onco-hematological pathologies such as acute myeloid leukemia, multiple myeloma, and several types of lymphomas. In hematological disorders, innate lymphoid cells may exert differential effects on the pathogenesis of hematologic malignancies. Furthermore, within the same disease, certain cell populations have been shown to play a protective role in antitumor immune responses, whereas others appear to suppress these responses. This review aims to provide an integrated description of innate lymphoid cells, their alterations in hematological malignancies, and potential preventive strategies, by proposing new specific targets for correcting anomalies. We also discuss the use of innate lymphoid cells as new therapies by applying chimeric antigen receptor-modified natural killer cells. We examine the current knowledge and outline future perspectives.