Major Histocompatibility Complex class II (MHC class II) (MHC II)

Major Histocompatibility Complex class II (MHC II) molecules are essential cell-surface glycoproteins primarily expressed on professional antigen-presenting cells (APCs) like dendritic cells and macrophages (Roche & Furuta, 2015). The peptide-binding groove of MHC II is a specialized structural domain that captures and displays exogenous peptides, such as those derived from tumor lysates or carrier proteins like Keyhole Limpet Hemocyanin (KLH), to CD4+ T-helper cells (Neefjes et al., 2011). This interaction is the cornerstone of the adaptive immune response, as it triggers T-cell proliferation and the secretion of cytokines that orchestrate anti-tumor activity (Sahin & Türeci, 2018). In clinical oncology, this target is utilized in personalized immunotherapy where a patient's own MHC II molecules are loaded with tumor-specific antigens to bypass immune evasion (Constantino et al., 2016). Therapeutic strategies often involve loading these grooves with tumor-specific antigens to overcome immune tolerance and promote tumor eradication (Swartz et al., 2012).

Other names

HLA class IIHuman Leukocyte Antigen class IIMHC-IIHLA-DRHLA-DQHLA-DPMHC class II-peptide complex

Presentation of exogenous antigens to CD4+ T-helper cells to initiate an adaptive immune response.