Biolegend, 584404, Biotinylated Recombinant Human CD28H (TMIGD2)-Fc Chimera (carrier-free)

CD28 homolog (CD28H), also referred to as TMIGD2 (Transmembrane and Immunoglobulin Domain Containing 2) and IGPR-1 (Immunoglobulin-containing and Proline-rich Receptor-1), is a member of the immunoglobulin superfamily. It is predominantly expressed in epithelial and endothelial cells. The CD28H structure consists of an extracellular domain resembling an immunoglobulin V-like (IgV-like) domain, which contains two potential glycosylation sites. It also features a transmembrane segment and a cytoplasmic tail with a tyrosine residue. CD28H was previously recognized both as a co-stimulatory receptor and as an adhesion molecule. HHLA2 (B7-H7) is the known ligand for CD28H. Connection of the CD28H and HHLA2 primarily co-stimulates human T cell growth through an Akt-dependent signaling cascade which mediate tumor resistance against NK cells and promotes cytokine production. CD28H is associated with immune dysregulation and angiogenesis. In autoimmune diseases, abnormal CD28H signaling can cause inappropriate T cell activation, resulting in tissue damage. Additionally, CD28H expression can promote the abnormal self-renewal and differentiation of acute myeloid leukemia cells via downstream signaling pathways like ERK1/2-p90RSK-CREB signaling. Targeting CD28 signaling with anti-CD28 mAb attenuates self-renewal of leukemia stem cells, providing promising therapeutic value.