• 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: The protein encoded by this gene functions as a key component of the system xc- amino acid antiporter. This heteromeric, sodium-independent transporter exhibits high selectivity for anionic amino acids, specifically exchanging extracellular cystine for intracellular glutamate. Beyond its metabolic role, this transporter is the dominant mediator permitting fusion and cellular entry of Kaposi sarcoma-associated herpesvirus (KSHV). Pathologically, overexpression of this gene in primary gliomas drives enhanced glutamate secretion via the system xc- transporter. The resulting elevated extracellular glutamate concentrations cause excitotoxic neuronal death. The SLC3A2 encodes a cell surface, transmembrane protein. The protein functions as the heavy chain of a heterodimer, forming a covalent linkage via disulfide bonds with one of several potential light chains. Acting as a transporter, it regulates intracellular calcium levels and facilitates the transport of L-type amino acids. Additionally, alternatively spliced transcript variants of this gene have been identified and characterized, resulting in the expression of distinct protein isoforms.
• Gene targeting strategy: The coding sequence of human SLC7A11 gene and SLC3A2 gene were randomly inserted into the genome of B-hSLC7A11/hSLC3A2 MC38. Human SLC7A11 and SLC3A2 are highly expressed on the surface of B-hSLC7A11/hSLC3A2 MC38.
• Application: B-hSLC7A11/hSLC3A2 MC38 tumor models can be used for preclinical evaluation of antibodies.

Human SLC7A11 and human SLC3A2 expression analysis in B-hSLC7A11/hSLC3A2 MC38 by flow cytometry. Single cell suspensions from wild-type MC38 and B-hSLC7A11/hSLC3A2 MC38 cultures were stained with species-specific anti-human SLC7A11 antibody and anti-human SLC3A2 (Ab1 and Ab2 were provided by the client.). Human SLC7A11 was detected on the surface of B-hSLC7A11/hSLC3A2 MC38 cells but not wild-type MC38 cells(A). Human SLC3A2 was highly expressed in the tumor cells(B). The 2-G02 clone of B-hSLC7A11/hSLC3A2 MC38 cells was used for in vivo experiments.

Human SLC7A11 expression evaluated in B-hSLC7A11/hSLC3A2 MC38 tumor cells by flow cytometry. B-hSLC7A11/hSLC3A2 MC38 cells were subcutaneously transplanted into C57BL/6 mice (female, 7-week-old, n=6), and on 35 days post inoculation, tumor cells were harvested and assessed for human SLC7A11 expression (LSBio, LS‑C142125) by flow cytometry. Due to the cross-reactivity of this antibody between humans and mice, the human SLC7A11 was detected in both the wild-type MC38 and the B-hSLC7A11/hSLC3A2 MC38. Therefore, B-hSLC7A11/hSLC3A2 MC38 can be used for in vivo efficacy studies of antibody therapeutics.

Subcutaneous homograft tumor growth of B-hSLC7A11/hSLC3A2 MC38 cells. B-hSLC7A11/hSLC3A2 MC38 cells (5x10⁵) and wild-type MC38 cells (5×10⁵) were subcutaneously implanted into C57BL/6 mice (female, 7-week-old, n=6). Tumor volume and body weight were measured three times a week. (A) Average tumor volume ± SEM. (B)  Body weight (Mean± SEM). Volume was expressed in mm³ using the formula: V=0.5 X long diameter X short diameter². As shown in panel A, B-hSLC7A11/hSLC3A2 MC38 cells were able to establish tumors in vivo and can be used for efficacy studies.