A preclinical model of double- versus single-unit unrelated cord blood transplantation.

Cord blood transplantation (CBT) with units containing total nucleated cell (TNC) dose >2.5 x 10(7)/kg is associated with improved engraftment and decreased transplant-related mortality. For many adults no single cord blood units are available that meet the cell dose requirements. We developed a dog model of CBT to evaluate approaches to overcome the problem of low cell dose cord blood units. This study primarily compared double- versus single-unit CBT. Unrelated dogs were bred and cord blood units were harvested. We identified unrelated recipients that were dog leukocyte antigen (DLA)-88 (class I) and DLA-DRB1 (class II) allele-matched with cryopreserved units. Each unit contained