Kita-Kyushu lung cancer antigen 1 peptide–HLA-A*01:01 complex (KK-LC-1–HLA-A*01:01)

The Kita-Kyushu lung cancer antigen 1 (KK-LC-1) peptide–HLA-A*01:01 complex is a highly specific tumor-associated antigen target used in cancer immunotherapy. KK-LC-1, also known as Cancer/testis antigen 83 (CT83), is a protein that is normally expressed only in the germ cells of the testis but is frequently overexpressed in various epithelial malignancies, including lung, gastric, and breast cancers. Because the testis is an immunologically privileged site lacking MHC class I expression, the presentation of KK-LC-1 peptides by HLA-A*01:01 on the surface of tumor cells provides a unique signature for immune recognition. This complex is primarily targeted by T-cell receptor (TCR) engineered T-cell therapies, which are designed to bind specifically to the peptide-MHC interface. Upon binding, these engineered T-cells undergo activation and release cytotoxic granules to selectively eliminate the cancer cells while sparing healthy somatic tissues. Clinical development of therapies targeting this complex is particularly promising for patients with HLA-A*01:01 positive tumors that express the KK-LC-1 antigen.

Other names

CT83 peptide–HLA-A*01:01 complexCancer/testis antigen 83–HLA-A*01:01 complexKK-LC-1–MHC class I complexKK-LC-1(52–60)–HLA-A*01:01

T-cell receptor (TCR) mediated recognition of the peptide-MHC complex leading to cytotoxic T-lymphocyte activation and tumor cell lysis.