T-cell receptor recognizing Keyhole Limpet Hemocyanin-derived peptide–MHC class II complexes (TCR-KLH:MHCII)

The T-cell receptor (TCR) recognizing Keyhole Limpet Hemocyanin (KLH)-derived peptide–MHC class II complexes is a specialized immune receptor found on the surface of CD4+ T-helper cells (Harris & Markl, 1999, PMID: 10466336). KLH is a highly immunogenic protein derived from the giant keyhole limpet, frequently used in clinical immunology as a carrier protein for haptens and as an adjuvant to stimulate the immune system (Swaminathan et al., 2014, PMID: 24750110). When dendritic cells (DCs) take up KLH, they process it into peptides and present them via Major Histocompatibility Complex (MHC) class II molecules (Lebrecht et al., 2004, PMID: 15164104). The specific TCR then recognizes this complex, initiating a robust adaptive immune response characterized by T-cell proliferation and cytokine production. In oncology, this interaction is leveraged to enhance the immunogenicity of cancer vaccines or to monitor the functional integrity of a patient's cellular immune system during treatment (Lamm et al., 1982, PMID: 7066883). While not a target for inhibition, this TCR-ligand interaction is a critical focal point for activation in various immunotherapeutic strategies, including the treatment of superficial bladder cancer. The receptor's ability to mount a de novo response makes it a valuable tool for assessing immune competence in immunocompromised patients. Therapeutic interventions often aim to maximize the frequency and affinity of these TCR-bearing cells to ensure a potent anti-tumor or anti-pathogen response.

Other names

KLH-specific T-cell receptorKeyhole Limpet Hemocyanin-specific TCRTCR-KLHKLH-specific CD4+ T-cell receptor

Agonism of the T-cell receptor via MHC-presented KLH peptides, leading to T-cell activation, cytokine release, and proliferation.