1. ¹Division of Immunotherapy, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
2. ²Maine General Medical Center, Waterville, ME, USA
3. ³Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA

Correspondence: Dr RK Burt, Division of Immunotherapy, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA. E-mail: rburt@northwestern.edu

Received 6 December 2006; Accepted 6 December 2006; Published online 5 February 2007.

Abstract

Peripheral blood stem cells (PBSC) were mobilized in 130 patients with autoimmune diseases undergoing autologous hematopoietic stem cell transplantation using cyclophosphamide 2 g/m² and either granulocyte colony-stimulating factor (G-CSF) 5 mcg/kg/day (for systemic lupus erythematosus (SLE) and secondary progressive multiple sclerosis, SPMS) or G-CSF 10 mcg/kg/day (for relapsing remitting multiple sclerosis (RRMS), Crohn's disease (CD), systemic sclerosis (SSc), and other immune-mediated disorders). Mobilization-related mortality was 0.8% (one of 130) secondary to infection. Circulating peripheral blood (PB) CD34⁺ cells/l differed significantly by disease. Collected CD34⁺ cells/kg/apheresis and overall collection efficiency was significantly better using Spectra apheresis device compared to the Fenwall CS3000 instrument. Patients with SLE and RRMS achieved the lowest and the highest CD34⁺ cell yields, respectively. Ex vivo CD34⁺ cell selection employing Isolex 300iv2.5 apparatus was significantly more efficient compared to CEPRATE CS device. Circulating PB CD34⁺ cells/l correlated positively with initial CD34⁺ cells/kg/apheresis and enriched product CD34⁺ cells/kg. Mean WBC and platelet engraftment (ANC>0.5 10⁹/l and platelet count >20 10⁹/l) occurred on days 9 and 11, respectively. Infused CD34⁺ cell/kg dose showed significant direct correlation with faster white blood cell (WBC) and platelet engraftment. When adjusted for CD34⁺ cell/kg dose, patients treated with a myeloablative regimen had significantly slower WBC and platelet recovery compared to non-myeloablative regimens.