Immuno-Grade A2A Adenosine Receptor Antibodies

The A2A adenosine receptor, encoded by the ADORA2A gene, is a G protein-coupled receptor that is highly expressed in the striatum, immune cells, blood vessels, and platelets. A2A primarily couples to Gs proteins, stimulating adenylyl cyclase activity and increasing intracellular cAMP levels, thereby modulating neuronal activity, inflammation, and vascular tone. In the central nervous system, A2A plays a key role in regulating dopaminergic neurotransmission and motor control through its interaction with dopamine receptors. A2A expression is regulated by developmental factors, inflammatory mediators, hypoxia, and receptor desensitization mechanisms involving phosphorylation and internalization. Dysregulated A2A signaling has been implicated in Parkinson’s disease, neuroinflammation, cancer, and cardiovascular disorders. Several pharmacological agents targeting A2A have been developed, with antagonists receiving particular clinical interest. Istradefylline is a selective A2A antagonist approved as an adjunctive treatment for Parkinson’s disease to reduce “off” episodes in patients receiving levodopa therapy. Additional selective A2A agonists and antagonists are under investigation for inflammatory, oncological, and neurodegenerative diseases. A2A receptor on immune cells (e.g. T cells, NK cells, dendritic cells and macrophages) mediate the immunosuppressive effects of adenosine, an action that produces a powerful tolerogenic/immunosuppressed state. As a result, A2A has been suggested as an immune checkpoint that produces a negative feedback loop in the tumor microenvironment. The A2A receptor primarily couples to Gs proteins ti stimulate adenylyl cyclase. The A2A receptor is constitutively phosphorylated at serine329 (pS329-A2A). Agonist activation enhances S329 phosphorylation. For more information on A2A receptor pharmacology please refer to the IUPHAR database. For further reading refer to:

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Fredholm BB, Frenguelli BG, Hills R, IJzerman AP, Jacobson KA, Klotz KN, Linden J, Müller CE, Schwabe U, Stiles GL. Adenosine receptors in GtoPdb v.2021.2. IUPHAR/BPS Guide to Pharmacology CITE. 2021; 2021(2).