• Origin: The MC38 cell line is derived from C57BL/6 murine colon adenocarcinoma cells. The cell line is a commonly used murine model for colorectal carcinoma.
• Background Information: HLA-A belongs to the HLA class I heavy chain paralogues. This class I molecule is a heterodimer consisting of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules play a central role in the immune system by presenting peptides derived from the endoplasmic reticulum lumen so that they can be recognized by cytotoxic T cells. Human Papillomavirus type 16 (HPV16) has been associated with a subset of head and neck cancers. Two HPV encoded oncogenic proteins, E6 and E7, are important for the malignant progression of HPV‑associated cancers.
• Gene targeting strategy: The B2M gene (Exon2 to Exon3) of mouse were replaced by the sequence encompassing the human B2M CDS, HLA-A*0201 gene that included leader sequence, α1 and α2 domains ligated to a fragment of the murine H-2Db gene containing the α3, transmembrane and cytoplasmic domains, HPV16 E6 and E7. The HPV16 E6 was linked to murine H-2Db’ cytoplasmic domains through T2A. The HPV16 E7 was linked to HPV16 E7 through IRES2. Human HLA-A2.1 is highly expressed on the surface of B-HLA-A2.1/HPV16 E6/E7 MC38.
• Application: B-HLA-A2.1/HPV16 E6/E7 MC38 tumor models can be used for preclinical evaluation of cancer vaccines.

Human HLA-A2.1 expression analysis in B-HLA-A2.1/HPV16 E6/E7 MC38 cells by flow cytometry. Single cell suspensions from wild-type MC38 and B-HLA-A2.1/HPV16 E6/E7 MC38 #1-C10 cultures were detected with species-specific anti-human HLA-A2.1 antibody (Biolegend, 343306). Human HLA-A2.1 was detected on the surface of B-HLA-A2.1/HPV16 E6/E7 MC38 cells but not wild-type MC38 cells(A). HPV16 E7 was detected in the tumor cells(B).

Human HLA-A2.1 expression evaluated in B-HLA-A2.1/HPV16 E6/E7 MC38 tumor cells by flow cytometry. B-HLA-A2.1/HPV16 E6/E7 MC38 cells were subcutaneously transplanted into B-HLA-A2.1 mice (Female, 8-week-old, n=7). Upon conclusion of the experiment, tumor cells were harvested and assessed with species-specific anti-human HLA-A2.1 antibody (Biolegend, 343306). Human HLA-A2.1 was highly expressed on the surface of tumor cells. Therefore, B-HLA-A2.1/HPV16 E6/E7 MC38 cells can be used for in vivo efficacy studies evaluating cancer vaccines.

Subcutaneous tumor growth of B-HLA-A2.1/HPV16 E6/E7 MC38. B-HLA-A2.1/HPV16 E6/E7 MC38 (1×10⁶) and wild-type MC38 cells (5×10⁵) were subcutaneously implanted into B-HLA-A2.1 mice (Female, 8-week-old, n=7). Tumor volume and body weight were measured twice a week. (A) Average tumor volume. (B) Body weight. Volume was expressed in mm³ using the formula: V=0.5 × long diameter × short diameter². Results indicate that B-HLA-A2.1/HPV16 E6/E7 MC38 cells were able to establish tumors in vivo and can be used for efficacy studies. Values are expressed as mean ± SEM.