Non-erythropoietic tissue-protective erythropoietin receptor complex (TPR (tissue-protective receptor), or sometimes EpoR/βcR)

The non-erythropoietic tissue-protective erythropoietin receptor complex is a heteromeric cell-surface receptor formed by the erythropoietin receptor (EpoR) and the β common receptor (CD131), which is also a component of the receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and interleukin-5[1][2][4]. Unlike the EpoR homodimer, which is responsible for red blood cell production, the EpoR/CD131 complex mediates the non-erythropoietic, tissue-protective effects of erythropoietin—such as neuroprotection, inhibition of apoptosis, anti-inflammation, and tissue healing—without stimulating erythropoiesis[1][2][3][4]. EPO derivatives such as carbamylated EPO and helix B surface peptides selectively engage this complex, demonstrating beneficial effects in preclinical models of ischemic, traumatic, and inflammatory injury across multiple organs, while avoiding the classical erythropoietic and pro-thrombotic side effects associated with EpoR homodimer activation[1][2][3]. The tissue-protective receptor is upregulated in response to injury and plays a critical protective role in the paracrine-autocrine response of tissues to damage.

Other names

EpoR/βcR heteroreceptorEPO tissue-protective receptorTissue-protective receptor (TPR)Erythropoietin non-erythropoietic tissue-protective receptor complexEPOR–CD131 receptor complex

Ligand (EPO or EPO analog) binds to the EpoR/CD131 heteroreceptor complex on non-erythroid cells \n- Activation leads to anti-apoptotic, anti-inflammatory, and pro-survival signaling cascades (JAK2/STAT3 or STAT5, PI3K/Akt, MAPK pathways), distinct from those responsible for erythropoiesis[3]\n- Modulation of endothelial nitric oxide synthase and reduction of tissue edema