Ex vivo depletion of TCRαβ+ T cells and CD19+ B cells (TCRαβ+/CD19+ depletion)

Ex vivo depletion of TCRαβ+ T cells and CD19+ B cells is a graft engineering strategy used primarily in haploidentical hematopoietic stem cell transplantation (HSCT) to prevent severe complications (Locatelli et al., 2017, Blood). This process is not a single molecular drug target but a cellular-level manipulation that selectively removes αβ T-cell receptor-positive T cells, which are the primary drivers of Graft-versus-Host Disease (GvHD), and CD19+ B cells to prevent Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disorder (Handgretinger et al., 2014, Bone Marrow Transplantation). Unlike traditional pan-T-cell depletion (CD3+ depletion), this method preserves γδ T cells and Natural Killer (NK) cells, which provide essential early anti-infective and anti-leukemic activity (Bertaina et al., 2014, Blood). The procedure is typically performed using automated immunomagnetic separation systems like the CliniMACS, which utilize biotinylated antibodies and streptavidin-coated microbeads (Miltenyi Biotec). This approach allows for the safe use of HLA-mismatched donors by reducing the need for intensive pharmacological GvHD prophylaxis while maintaining a potent graft-versus-leukemia effect.

Other names

Alpha/beta T-cell and B-cell depletionTCRαβ/CD19-depleted haploidentical HSCTGraft engineeringSelective T-cell depletionTCR alpha/beta and CD19 depletion

Selective ex vivo removal of alloreactive αβ T cells and EBV-carrying B cells from a donor graft using immunomagnetic separation to prevent GvHD and PTLD while preserving innate-like T cells and NK cells.