HLA-F Antibody - #DF12204

Non-classical major histocompatibility class Ib molecule postulated to play a role in immune surveillance, immune tolerance and inflammation. Functions in two forms, as a heterotrimeric complex with B2M/beta-2 microglobulin and a peptide (peptide-bound HLA-F-B2M) and as an open conformer (OC) devoid of peptide and B2M (peptide-free OC). In complex with B2M, presents non-canonical self-peptides carrying post-translational modifications, particularly phosphorylated self-peptides. Peptide-bound HLA-F-B2M acts as a ligand for LILRB1 inhibitory receptor, a major player in maternal-fetal tolerance. Peptide-free OC acts as a ligand for KIR3DS1 and KIR3DL2 receptors. Upon interaction with activating KIR3DS1 receptor on NK cells, triggers NK cell degranulation and anti-viral cytokine production. Through interaction with KIR3DL2 receptor, inhibits NK and T cell effector functions. May interact with other MHC class I OCs to cross-present exogenous viral, tumor or minor histompatibility antigens to cytotoxic CD8+ T cells, triggering effector and memory responses. May play a role in inflammatory responses in the peripheral nervous system. Through interaction with KIR3DL2, may protect motor neurons from astrocyte-induced toxicity.

N-glycosylated.

Cell membrane>Single-pass type I membrane protein. Early endosome membrane. Lysosome membrane.
Note: For cross-presentation transits from the cell surface through endosomal pathway to lysosomes, where the peptide is generated from internalized exogenous antigen.

Expressed in resting B cells (at protein level). Expressed in secondary lymphoid organs rich in B and T cells such as the tonsils, spleen, and thymus (at protein level). Expressed in the endothelial cells of the tonsils. Expressed on activated lymphoid cells including B cells, NK cells, CD4+ T cells and memory T cells (at protein level). Expressed in motor neurons of spinal cord.

Forms a heterotrimer with B2M and a self-peptide. Binds a diverse number of peptides ranging from 7 to more than 30 amino acids. Peptide-bound HLA-F-B2M interacts with LILRB1 and LILRB2 but not with KIR3DS1 or KIR3DL2; this interaction is direct. The OC form interacts with KIR3DS1, KIR2DS4 and KIR3DL2; this interaction is direct. Interacts with TAP1-TAP2 complex and CALR; this interaction is required for appropriate folding and peptide loading. Interacts with the coat protein complex II and 14-3-3 proteins; these interactions likely control the anterograde ER-to-Golgi transport of HLA-F. HLA-F-B2M complex interacts with the heavy chain of other MHC class I molecules including HLA-A and HLA-E; this interaction may regulate the intracellular trafficking and the stability of peptide-free MHC class I OCs.

Belongs to the MHC class I family.