ABSTRACT:

IL-7 is one of the very important cytokines in the regulation and maintenance of immune responses. IL-7 has been described as a very pivotal lymphocyte development, homeostasis, and activation mediator. Recent studies focused on the pathways influenced by IL-7 and their role in innate and adaptive immunities. Interleukin-7 (IL-7) is a critical cytokine in the development and homeostasis of T cells, as well as the signaling of other immune cells, such as natural killer (NK) cells. IL-7 signaling is also important for the majority of T cell functions and disease associations, which include protection against infectious diseases, autoimmunity, and tumor malignancies. This paper reviews the current findings on IL-7 and its role in the immune response, with particular emphasis on the mechanisms of signaling pathways it induces and its effects on lymphocyte functions, therefore opening a window for a future therapeutic application. It also presents recent research findings on the role of IL-7 in the diseased state dynamics of many illnesses, which consequently underscores possible therapeutic applications while simultaneously pinpointing the shortcomings in the existing knowledge regarding the biology of IL-7.

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