A beta chain of antigen-presenting major histocompatibility complex class II (MHCII) molecule. In complex with the alpha chain HLA-DRA, displays antigenic peptides on professional antigen presenting cells (APCs) for recognition by alpha-beta T cell receptor (TCR) on HLA-DRB1-restricted CD4-positive T cells. This guides antigen-specific T-helper effector functions, both antibody-mediated immune response and macrophage activation, to ultimately eliminate the infectious agents and transformed cells. Typically presents extracellular peptide antigens of 10 to 30 amino acids that arise from proteolysis of endocytosed antigens in lysosomes. In the tumor microenvironment, presents antigenic peptides that are primarily generated in tumor-resident APCs likely via phagocytosis of apoptotic tumor cells or macropinocytosis of secreted tumor proteins. Presents peptides derived from intracellular proteins that are trapped in autolysosomes after macroautophagy, a mechanism especially relevant for T cell selection in the thymus and central immune tolerance. The selection of the immunodominant epitopes follows two processing modes: ''bind first, cut/trim later'' for pathogen-derived antigenic peptides and ''cut first, bind later'' for autoantigens/self-peptides. The anchor residue at position 1 of the peptide N-terminus, usually a large hydrophobic residue, is essential for high affinity interaction with MHCII molecules.

HLA class II histocompatibility antigen, DRB1 beta chain
Human leukocyte antigen DRB1 (HLA-DRB1)
HLA-DRB1

p01911

WB,IHC,IF,ICC

WB 1:1000
IHC 1:1000
IF 1:100
ICC 1:100-1:400

Human

Predicted size: 30 kDa

Rabbit

Cell membrane. Endoplasmic reticulum.

Protein A affinity purified.

Recombinant Rabbit monoclonal

IgG

Liquid

1*TBS (pH7.4), 0.05% BSA, 40% Glycerol. Preservative: 0.05% Sodium Azide.

Store at +4°C short term. Store at -20°C long term. Avoid freeze / thaw cycle.