Keratinocytes efficiently process endogenous antigens for cytotoxic T-cell mediated lysis

Area of Science:

• Immunology
• Cancer Research
• Cell Biology

Background:

• Cytotoxic T lymphocyte (CTL) responses are crucial for immunotherapy against epithelial tumors and viral infections.
• Limited research exists on the susceptibility of primary epithelial cells to CTL-mediated lysis when expressing endogenous antigens.

Purpose of the Study:

• To investigate if primary keratinocytes (KCs) expressing endogenous antigens are effective targets for CTL-mediated killing.
• To determine the susceptibility of KCs to CTL lysis in the context of immunotherapy.

Main Methods:

• Primary keratinocytes (KCs) engineered to express ovalbumin (OVA) as a transgene were used.
• Cell surface presentation of H-2K(b)/SIINFEKL complexes on KCs was measured.
• OVA-specific CTLs were used to assess the lysis of engineered KCs.
• The effect of interferon-gamma pretreatment on KC susceptibility was evaluated.

Main Results:

• Primary KCs expressing endogenous OVA presented measurable H-2K(b)/SIINFEKL complexes.
• OVA-specific CTLs effectively killed the engineered primary KCs.
• Target cell lysis was comparable to the traditional EL4 target cell line.
• Pretreatment with interferon-gamma enhanced KC susceptibility to CTL-mediated lysis.

Conclusions:

• Primary keratinocytes are susceptible to CTL-mediated apoptosis when targeting endogenous antigens.
• These findings support the potential of primary KCs as targets in immunotherapy for epithelial cancers and viral diseases.