Enhanced antitumor efficacy of next-generation B7-H3 chimeric antigen receptor T cells containing CD28, CD137 and CD27 costimulatory domains in multiple myeloma
Issued Date
2026-03-01
Resource Type
ISSN
14653249
eISSN
14772566
Scopus ID
2-s2.0-105027236616
Pubmed ID
41539232
Journal Title
Cytotherapy
Volume
28
Issue
3
Rights Holder(s)
SCOPUS
Bibliographic Citation
Cytotherapy Vol.28 No.3 (2026)
Suggested Citation
Natungnuy K., Luangwattananun P., Supimon K., Yuti P., Rujirachaivej P., Sujjitjoon J., Junking M., Okada S., Yenchitsomanus P.t. Enhanced antitumor efficacy of next-generation B7-H3 chimeric antigen receptor T cells containing CD28, CD137 and CD27 costimulatory domains in multiple myeloma. Cytotherapy Vol.28 No.3 (2026). doi:10.1016/j.jcyt.2025.102014 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/114638
Title
Enhanced antitumor efficacy of next-generation B7-H3 chimeric antigen receptor T cells containing CD28, CD137 and CD27 costimulatory domains in multiple myeloma
Corresponding Author(s)
Other Contributor(s)
Abstract
Background: Multiple myeloma (MM) remains an incurable disease despite significant advancements in treatment strategies. Chimeric antigen receptor (CAR) T cell therapies targeting B-cell maturation antigen have demonstrated clinical promise; however, their effectiveness is often limited by disease relapse, partly due to CAR T cell exhaustion. B7-homolog 3 (B7-H3), an immune checkpoint molecule that is overexpressed in MM and may suppress T cell function, represents a potential alternative target to improve CAR T cell efficacy and enhance disease control. Methods: We engineered and characterized three generations of B7-H3-specific CAR T cells, second (B7H3.CAR2), third (B7H3.CAR3) and next-generation (B7H3.CAR-NG), each incorporating distinct costimulatory domains. B7H3.CAR2 contains the CD28 costimulatory domain, B7H3.CAR3 combines CD28 and CD137, and B7H3.CAR-NG incorporates CD28, CD137, and CD27 costimulatory modules. Their expression and function were evaluated in vitro using MM cell lines with differential B7-H3 expression. CAR T cell phenotype, cytotoxic activity, persistence and cytokine secretion were assessed through both short- and long-term coculture assays. Results: B7-H3 expression levels varied across MM cell lines, with MM.1S exhibiting the highest and NCI-H929 the lowest expression. Second-, third- and next-generation B7-H3-specific CAR T cells (B7H3.CAR2, B7H3.CAR3, and B7H3.CAR-NG) were successfully generated, with CAR expression rates of 31.27 ± 8.63%, 29.90 ± 8.86% and 37.27 ± 8.69%, respectively. All three CAR T cell types selectively lysed B7-H3-positive MM.1S cells in an antigen density-dependent manner while sparing B7-H3-negative SupT1 cells. Among them, B7H3.CAR-NG T cells showed the highest cytotoxicity, lysing 53.22 ± 9.28% of MM.1S cells at a 1:1 effector-to-target ratio, compared to 11.66 ± 1.62% of SupT1 cells. In long-term cocultures, CAR-NG T cells demonstrated superior tumor control and persistence, likely due to a higher frequency of central memory T cells. Cytokine analysis revealed elevated secretion of effector molecules by CAR-NG T cells, indicating enhanced antitumor functionality. Conclusions: B7-H3-specific CAR T cells exhibit potent antitumor activity against MM, with the next-generation construct (B7H3.CAR-NG) demonstrating superior cytotoxicity, persistence and cytokine production. These findings support the potential of B7H3.CAR-NG T cells as a promising therapeutic strategy for MM.