Nam, Giri Yeon, Hye Ran Park, Hyung Bae Chang, Hanna Kim, Ji Hwan Cho, Byoung-Kyu Jung, Hyeryeon Yi, Eugene C. Kim, Seoyeon An, Joon-Yong Lee, Ji Eun Lee, Youngjae Lee, Seoho Lim, Hyeonji Shon, Woo-Jeong Hwang, Eun Mi Ryu, Hoon Chang, Jun Choi, Kyungho Choi, Eun Young 2025-09-30T06:33:21Z 2025-09-30T06:33:21Z 2025-09-30 2025-08 https://pubs.kist.re.kr/handle/201004/153279 Despite the efficacy of chimeric antigen receptor (CAR)-T cells in selected hematological malignancies, further improvement on CAR-T designs is still desirable. We hypothesize that modifying the CAR structure to enhance immunological synapse (IS) stabilization and CAR target-binding may be a feasible strategy. Here we show that the membrane protein, CD99, is critical for IS formation in T cells by mediating actin-microtubule interaction. CD99 deficiency abolishes IS formation and prevents effective in vivo T cell immunity. Mechanistically, CD99 interacts with microtubules and actins through the transmembrane and cytoplasmic domains, respectively, with which myosin and IQGAP1 interact. As such, incorporating the transmembrane and juxtamembrane domains of CD99 into the CAR structure enhances IS formation and improves the therapeutic efficacy of human CAR-T cells against lymphoma in immune-deficient mice. Our data thus suggest that CD99-mediated IS stabilization may help improve CAR design and efficacy. English Nature Publishing Group CD99-mediated immunological synapse formation potentiates CAR-T cell function Article 10.1038/s41467-025-63184-w 1 Nature Communications, v.16, no.1 Nature Communications 16 1 Y scie scopus 001560602900024 2-s2.0-105014174403 Multidisciplinary Sciences Science & Technology - Other Topics Article MHC CLASS-I CENTROSOME POLARIZATION CD99 MYOSIN LYMPHOCYTES ENGAGEMENT REORGANIZATION ACTIVATION GENERATION MOLECULES