{"title":"NKG2D/CD28 chimeric receptor boosts cytotoxicity and durability of CAR-T cells for solid and hematological tumors.","authors":"Xia Teng, Shance Li, Chaoting Zhang, Huirong Ding, Zhihua Tian, Yuge Zhu, Ting Liu, Guanyu Zhang, Kang Sun, Huimin Xie, Jiaxin Tu, Zheming Lu","doi":"10.1186/s40164-025-00646-3","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>CAR-T cell therapy faces challenges in solid tumor treatment and hematologic malignancy relapse, among which the limited persistence of CAR-T cells and target antigen downregulation are prominent factors. Therefore, we engineered an NKG2D/CD28 chimeric co-stimulatory receptor (CCR), leveraging its broad ligand expression on tumors to enhance the antitumor activity of MSLN CAR and CD19 CAR-T cells.</p><p><strong>Methods: </strong>We generated MSLN CAR-T and CD19 CAR-T cells co-expressing the NKG2D/CD28 CCR and assessed their antitumor efficacy in vitro and in vivo. CAR-T cell activation, differentiation, and exhaustion were analyzed over time following tumor antigen stimulation. Furthermore, a chronic antigen stimulation model was established using tumor cells with low antigen density to simulate the sustained antigenic pressure encountered in vivo treatment conditions.</p><p><strong>Results: </strong>Our study shows that NKG2D/CD28&CAR-T cells exhibit enhanced cytotoxicity against tumor cells, especially those with low antigen density, both in vitro and in vivo. Compared to conventional second-generation MSLN CAR or CD19 CAR-T cells, these dual-targeted NKG2D/CD28&CAR-T cells demonstrate superior sensitivity in recognizing and lysing low-density antigen-expressing lung cancer and leukemia cells, and they are capable of eradicating tumors with low-density antigen expression in vivo. Furthermore, the complementary co-stimulation provided by the 4-1BB and CD28 intracellular domains in the CAR and NKG2D/CD28 promotes cytokine secretion, reduces CAR-T cell exhaustion, and enhances the in vivo persistence of CAR-T cells, significantly improving their antitumor efficacy.</p><p><strong>Conclusion: </strong>The combination of CAR and NKG2D/CD28 offers a potent strategy to enhance the cytotoxicity and durability of CAR-T cells. This approach is promising for improving therapeutic outcomes in solid and hematological tumors and preventing recurrence in tumors with low target antigen density.</p>","PeriodicalId":12180,"journal":{"name":"Experimental Hematology & Oncology","volume":"14 1","pages":"52"},"PeriodicalIF":9.4000,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11967049/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Experimental Hematology & Oncology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1186/s40164-025-00646-3","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"HEMATOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: CAR-T cell therapy faces challenges in solid tumor treatment and hematologic malignancy relapse, among which the limited persistence of CAR-T cells and target antigen downregulation are prominent factors. Therefore, we engineered an NKG2D/CD28 chimeric co-stimulatory receptor (CCR), leveraging its broad ligand expression on tumors to enhance the antitumor activity of MSLN CAR and CD19 CAR-T cells.
Methods: We generated MSLN CAR-T and CD19 CAR-T cells co-expressing the NKG2D/CD28 CCR and assessed their antitumor efficacy in vitro and in vivo. CAR-T cell activation, differentiation, and exhaustion were analyzed over time following tumor antigen stimulation. Furthermore, a chronic antigen stimulation model was established using tumor cells with low antigen density to simulate the sustained antigenic pressure encountered in vivo treatment conditions.
Results: Our study shows that NKG2D/CD28&CAR-T cells exhibit enhanced cytotoxicity against tumor cells, especially those with low antigen density, both in vitro and in vivo. Compared to conventional second-generation MSLN CAR or CD19 CAR-T cells, these dual-targeted NKG2D/CD28&CAR-T cells demonstrate superior sensitivity in recognizing and lysing low-density antigen-expressing lung cancer and leukemia cells, and they are capable of eradicating tumors with low-density antigen expression in vivo. Furthermore, the complementary co-stimulation provided by the 4-1BB and CD28 intracellular domains in the CAR and NKG2D/CD28 promotes cytokine secretion, reduces CAR-T cell exhaustion, and enhances the in vivo persistence of CAR-T cells, significantly improving their antitumor efficacy.
Conclusion: The combination of CAR and NKG2D/CD28 offers a potent strategy to enhance the cytotoxicity and durability of CAR-T cells. This approach is promising for improving therapeutic outcomes in solid and hematological tumors and preventing recurrence in tumors with low target antigen density.
期刊介绍:
Experimental Hematology & Oncology is an open access journal that encompasses all aspects of hematology and oncology with an emphasis on preclinical, basic, patient-oriented and translational research. The journal acts as an international platform for sharing laboratory findings in these areas and makes a deliberate effort to publish clinical trials with 'negative' results and basic science studies with provocative findings.
Experimental Hematology & Oncology publishes original work, hypothesis, commentaries and timely reviews. With open access and rapid turnaround time from submission to publication, the journal strives to be a hub for disseminating new knowledge and discussing controversial topics for both basic scientists and busy clinicians in the closely related fields of hematology and oncology.