Recombinant Human CD276 antigen (CD276), partial (Active)

This recombinant human CD276 protein is a biologically active form produced in mammalian cells, ensuring proper folding and post-translational modifications. It contains the partial extracellular domain spanning amino acids 29 to 245 and is fused with a C-terminal 10xHis tag to facilitate purification and detection. This recombinant CD276 protein shows high purity, with levels exceeding 95% as confirmed by both SDS-PAGE and SEC-HPLC. Functional validation was performed using ELISA, where CD276 immobilized at 2 μg/mL demonstrated specific binding to the anti-CD276 recombinant antibody (CSB-RA733578MA1HU), yielding an EC₅₀ in the range of 47.12 to 54.16 ng/mL. These characteristics make it a dependable tool for research involving immune checkpoint regulation, antibody development, and cancer immunotherapy targeting CD276.

CD276, also known as B7-H3, is a member of the B7 family of immune checkpoint proteins that has gained significant attention in cancer immunology due to its multifaceted roles in tumor progression and immune evasion. Originally identified for its costimulatory effects in T cell activation, recent findings illustrate that CD276 primarily exhibits immunosuppressive properties in the tumor microenvironment (TME). High expression levels of CD276 have been associated with several malignancies, including melanoma, pancreatic cancer, and colorectal cancer, where its interaction with immune cells contributes to tumor progression and immune escape mechanisms [1][2][3][4].

The dual role of CD276 as both a costimulatory and a co-inhibitory molecule underscores its complexity. While it can enhance T-cell responses under certain conditions, in the context of cancer, CD276 frequently inhibits T-cell activation and promotes the survival of cancer stem cells. Studies indicate that blocking CD276 can enhance T-cell-mediated antitumor immunity, which is crucial for developing effective immunotherapy strategies [5][3]. For instance, research has demonstrated that the blockade of CD276 enhances CD8+ T cell infiltration and activity against tumors, presenting a therapeutic target for improving immunotherapy outcomes [6][7].

Additionally, CD276's expression is significantly associated with poor clinical outcomes, as its high levels in tumors correlate with reduced infiltration of T cells and other immune effector cells. This correlation has been noted particularly in cancers such as ovarian cancer and pancreatic cancer, where the presence of CD276-expressing tumor cells has been linked to tumor metastasis and resistance to therapies [6][7][4]. Moreover, CD276 facilitates various tumor-promoting processes, including angiogenesis and tumor cell proliferation, thereby augmenting the aggressive phenotype of certain cancers [8][9][10].

References:
[1] G. Li, X. Zhu, & C. Liu. Characterization of immune infiltration and construction of a prediction model for overall survival in melanoma patients. Frontiers in Oncology, vol. 11, 2021. https://doi.org/10.3389/fonc.2021.639059
[2] W. Zhou and W. Jin. B7-h3/cd276: an emerging cancer immunotherapy. Frontiers in Immunology, vol. 12, 2021. https://doi.org/10.3389/fimmu.2021.701006
[3] T. Deng, Y. Deng, et al. Rapidly-manufactured cd276 car-t cells exhibit enhanced persistence and efficacy in pancreatic cancer. Journal of Translational Medicine, vol. 22, no. 1, 2024. https://doi.org/10.1186/s12967-024-05462-7
[4] A. Getu, A. Tigabu, M. Zhou, J. Lu, Ø. Fodstad, & M. Tan. New frontiers in immune checkpoint b7-h3 (cd276) research and drug development. Molecular Cancer, vol. 22, no. 1, 2023. https://doi.org/10.1186/s12943-023-01751-9
[5] X. Liu, Y. Chen, et al. Pan-cancer analysis reveals correlation between rab3b expression and tumor heterogeneity, immune microenvironment, and prognosis in multiple cancers. Scientific Reports, vol. 14, no. 1, 2024. https://doi.org/10.1038/s41598-024-60581-x
[6] X. Liu, P. Liu, et al. Impact of human papillomavirus on the tumor microenvironment in oropharyngeal squamous cell carcinoma. International Journal of Cancer, vol. 150, no. 3, p. 521-531, 2021. https://doi.org/10.1002/ijc.33849
[7] H. Baysal, V. Siozopoulou, et al. The prognostic impact of the immune signature in head and neck squamous cell carcinoma. Frontiers in Immunology, vol. 13, 2022. https://doi.org/10.3389/fimmu.2022.1001161
[8] M. Lv, B. Liu, et al. Engineered biomimetic nanovesicles synergistically remodel folate-nucleotide and γ-aminobutyric acid metabolism to overcome sunitinib-resistant renal cell carcinoma. Acs Nano, vol. 18, no. 40, p. 27487-27502, 2024. https://doi.org/10.1021/acsnano.4c08055
[9] Z. Zhang, J. Xu, Z. Song, J. Zhang, Y. Lin, & J. Ouyang. Bioinformatic analysis and clinical case studies identify cd276 as a promising diagnostic biomarker for clear cell renal cell carcinoma. Cancer Control, vol. 31, 2024. https://doi.org/10.1177/10732748241250181
[10] S. Seaman, Z. Zhu, et al. Eradication of tumors through simultaneous ablation of cd276/b7-h3-positive tumor cells and tumor vasculature. Cancer Cell, vol. 31, no. 4, p. 501-515.e8, 2017. https://doi.org/10.1016/j.ccell.2017.03.005