Protein tyrosine phosphatase receptor type C (CD45RA isoform) (CD45RA)

Protein tyrosine phosphatase receptor type C (PTPRC), specifically the CD45RA isoform, is a transmembrane glycoprotein essential for regulating the signaling threshold of T and B cell receptors (UniProt P08575). It is characterized by the presence of the A exon and is primarily expressed on naive T lymphocytes, as well as subsets of B cells and natural killer cells (PMID: 24652961). In the context of ex vivo manufacturing for hematopoietic stem cell transplantation, CD45RA+ leukocytes are targeted for selective depletion to improve patient outcomes. This depletion aims to remove naive T cells, which are the primary mediators of graft-versus-host disease (GvHD) due to their broad repertoire of alloreactive TCRs (PMID: 35130348). By contrast, CD45RO+ memory T cells are preserved, allowing the recipient to maintain protective immunity against common pathogens like CMV and EBV. The targeting is typically achieved using monoclonal antibodies conjugated to paramagnetic beads in automated systems like the CliniMACS (Miltenyi Biotec). Clinical trials have demonstrated that CD45RA-depleted grafts can significantly reduce the incidence of chronic GvHD without compromising engraftment or increasing relapse rates (PMID: 35130348).

Other names

PTPRCLeukocyte common antigenLCAT200CD45 isoform RACD45

Selective ex vivo depletion of CD45RA-expressing naive T cells from a cellular graft to prevent graft-versus-host disease while preserving memory T cells for infection control (PMID: 24652961).