Human GUCY2C Stable Cell Line - HEK293

While checkpoint inhibitors and CAR-T cell therapies have initiated a paradigm shift in the management of some cancers, there remains an unmet need for improved treatment of colorectal cancer (CRC), the 4th leading cause of cancer and 2nd leading cause of cancer mortality worldwide. The researchers evaluated the cancer vaccine Ad5-GUCY2C-PADRE in a phase I clinical study of early-stage colorectal cancer patients. Ten patients received a single intramuscular injection of 10^11 viral particles (vp). Safety and immunological efficacy were assessed over 6 months. Results showed no adverse events > grade 1. GUCY2C-specific CD8 T-cell responses were detected in 40% of patients, reflecting preclinical findings in mice where CD4 T-cell responses were eliminated by self-tolerance. Pre-existing Ad5 neutralizing antibodies correlated with reduced vaccine efficacy, indicating their potential to inhibit GUCY2C-specific immune responses. This study demonstrates Ad5-GUCY2C-PADRE's ability to induce targeted immune responses in colorectal cancer patients without autoimmune reactions. Reduced vaccine efficacy was linked with pre-existing Ad5 neutralizing antibodies, suggesting that these antibodies may suppress GUCY2C-specific immune responses. This study shows that Ad5-GUCY2C-PADRE can stimulate specific immune responses in patients with colorectal cancer without causing autoimmune reactions.

Figure 1. The researchers utilized suspension HEK293 cells to produce Hexahistidine-tagged human GUCY2CECD protein (amino acids 1–429). The protein was purified to > 90% purity using immobilized metal affinity chromatography (IMAC). This cell line facilitated efficient protein expression and purification, crucial for subsequent biochemical and structural studies of GUCY2CECD. (Snook AE, et al., 2019)