Targeting site-specific N-glycosylated B7H3 induces potent antitumor immunity

• Published in: Nature communications Vol. 16; no. 1; pp. 3546 - 18
• Main Authors: Huang, Yun, Zhong, Wen-Qing, Yang, Xiao-Yu, Shan, Jia-Lu, Zhou, Ling, Li, Zhi-Ling, Guo, Yi-Qing, Zhang, Kai-Ming, Du, Tian, Zhang, Hai-Liang, Hu, Bing-Xin, Chen, Yu-Hong, Yang, Dong, Feng, Gong-Kan, Tang, Jun, Zhu, Xiao-Feng, Deng, Rong
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.04.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 13/1; 13/31; 13/51; 13/89; 38/109; 38/35; 631/208/176; 631/250/1619/554; 631/67/1059; 631/67/580; 64/60; 82/29; Animals; Antibodies, Monoclonal - immunology; Antibodies, Monoclonal - pharmacology; Asparagine; Asparagine - metabolism; B7 Antigens - genetics; B7 Antigens - immunology; B7 Antigens - metabolism; Biodegradation; Cell activation; Cell Line, Tumor; Cell Membrane - metabolism; Cell Proliferation; Cell surface; Cytotoxicity; Degradation; Endoplasmic reticulum; Endoplasmic Reticulum - metabolism; Female; Glycosylation; Golgi apparatus; Golgi Apparatus - metabolism; HEK293 Cells; Humanities and Social Sciences; Humans; Immune checkpoint; Immunity; Immunotherapy; Immunotherapy - methods; Internalization; Localization; Lymphocyte Activation; Lymphocytes; Lymphocytes T; Membranes; Mice; Mice, Inbred C57BL; Monoclonal antibodies; multidisciplinary; N-glycans; Neoplasms - immunology; Polysaccharides; Polysaccharides - metabolism; Protein Transport; Proteins; Residues; Science; Science (multidisciplinary); T-Lymphocytes, Cytotoxic - immunology; Translocation
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-025-58740-3

B7H3, an immune checkpoint molecule, is a highly N-glycosylated membrane protein. However, the key glycosylated asparagine residues that mediate the function of the B7H3 protein are still unclear. Here we identify that N-glycans attached to asparagine residues N91/309 and N104/322 are required for proper B7H3 localization on the cell surface membrane. We demonstrate that mutations in these two pairs of N-glycosylation sites induce ER accumulation of B7H3 by blocking its ER-to-Golgi translocation and subsequently promote its degradation via the endoplasmic reticulum-associated protein degradation pathway. Additional evidence suggests that N-glycosylation at N91/309 and N104/322 of B7H3 is essential for its inhibition of T-cell proliferation and activation. More importantly, a monoclonal antibody, Ab-82, preferentially targeting B7H3 glycosylated at N91/309 and N104/322 is developed, which exhibits the ability to elicit cytotoxic T lymphocyte-mediated antitumor immunity via B7H3 internalization. Together, these findings offer a rationale for targeting glycosylated B7H3 as a potential strategy for immunotherapy. Glycosylated asparagine residues that mediate the function of the B7H3 protein are unclear. Here the authors identify the important N-glycosylation sites for B7H3 cell surface localization and T cell inhibition, followed by the development of N91/309 and N104/322 preferentially targeting monoclonal antibody manifesting enhanced antitumor immunity.