Natural killer cell immunotherapies beyond cancer

Natural killer (NK) cells are innate lymphocytes that play central roles in immune surveillance, tissue homeostasis, and the regulation of adaptive immunity. While traditionally studied in the context of viral infection and cancer, it is now clear that NK cells also influence the pathogenesis and outcomes of a wide range of non-malignant conditions. Growing evidence links NK cell activity to autoimmune diseases, transplantation tolerance or rejection, neurodegenerative disorders, and chronic infections. At the same time, advances in cellular engineering and immunotherapy have expanded opportunities to harness NK cells as therapeutic agents in these settings. In this review, we summarize recent progress in understanding how NK cells contribute to the development and regulation of non-malignant diseases, and highlight emerging strategies to harness NK cells for therapeutic benefit. By integrating findings across diverse fields, we aim to provide a comprehensive perspective on NK cell biology beyond cancer, emphasizing their dual potential as both drivers of pathology and tools for intervention. Ultimately, a deeper understanding of NK cell function in these contexts will open new avenues for precision immunotherapy and improve outcomes for patients with non-malignant diseases.