Comparison of three mobilization protocols for peripheral blood stem cell apheresis with Spectra Optia continuous mononuclear cell protocol in healthy dogs.

Peripheral blood stem cell (PBSC) transplantation following consolidation therapy is a feasible treatment option for canine haematological malignancies. In veterinary medicine, haematopoietic stem cells are generally mobilized into peripheral circulation using a granulocyte colony-stimulating factor (G-CSF). This pilot study aimed to evaluate the haematopoietic stem cell mobilization effect of three different regimens for PBSC apheresis with Spectra Optia continuous mononuclear cell (CMNC) protocol in healthy dogs. Stem cell mobilization was performed using high-dose plerixafor (CXCR-4 inhibitor) alone, a G-CSF alone, or a combination of the low-dose plerixafor and G-CSF. Three dogs were assigned to each mobilization protocol. Regardless of the mobilization protocol, the total blood volume processed was uniformly set as 270 mL/kg and many PBSCs, defined as CD34+/CD45 cells, within the apheresis product were compared. Changes in complete blood count, PBSC counts, and blood chemistry analysis were monitored before, during, and after apheresis. All dogs tolerated the apheresis procedure using the Spectra Optia system with minimal adverse effects. The mean PBSC counts of the apheresis products for plerixafor, G-CSF, and the combination groups were 1.3 ± 0.24, 4.2 ± 0.47, and 6.4 ± 0.9 × 10 cells/kg, respectively. The apheresis procedure using Spectra Optia CMNC protocol in dogs is safe and feasible. Furthermore, PBSC mobilization with a combination of G-CSF and plerixafor appeared more effective than either compound alone in mobilizing PBSC to the peripheral blood in dogs.