新型自然杀伤细胞既抗癌又能“自保”

Core Insights - A new type of chimeric antigen receptor-natural killer (CAR-NK) cell has been developed by scientists from MIT and Harvard, which can precisely destroy cancer cells while evading the human immune system, potentially addressing the long-standing issue of immune rejection in cell therapies [1][2] Group 1: CAR-NK Cell Development - The CAR-NK therapy typically requires extracting NK cells from patients, genetically modifying them to express chimeric antigen receptors, and then expanding them in vitro before reintroducing them into the patient [1] - The challenge with using NK cells from healthy donors is that the recipient's immune system often recognizes these foreign cells as "non-self" and eliminates them [1] Group 2: Mechanism of Action - The research team has enabled donor NK cells to learn an "invisibility trick" by removing HLA-1 class molecules, which are identity recognition proteins, allowing NK cells to evade host T cell attacks [2] - Short interfering RNA was introduced to silence genes responsible for HLA-1 production, while also integrating CAR genes and genes encoding PD-L1 or single-chain HLA-E (SCE) to enhance the anti-cancer capabilities of NK cells [2] Group 3: Experimental Results - In experiments targeting lymphoma, the modified CAR-NK cells nearly completely eradicated tumors, whereas unmodified or only CAR gene-carrying NK cells were quickly eliminated by the host immune system and failed to control cancer progression [2] - The new CAR-NK cells also exhibited a lower risk of triggering cytokine release syndrome [2] Group 4: Future Implications - The team predicts that CAR-NK cells may gradually replace CAR-T cells in cancer treatment [2] - The gene construction strategies developed in this research could be applied to optimize CAR-NK therapies for other types of cancer [2]