Generally, induction of T lymphocyte activation, proliferation and function not only requires the recognition between the T-cell receptor (TCR) and specific major histocomptability complex (MHC) peptide complexes expressed on the surface of antigen presenting cells (APCs) (such as DCs and tumor cells), but also the interaction between co-stimulatory molecules on T-cells and APCs [44], [45]. The gene discussed is HLA-C; the disease is neoplasm.