Collection of peripheral progenitor cells in paediatric patients with a new programme for the collection of mononuclear cells.

Abstract

When harvesting peripheral progenitor cells (PPC) in children, the special situation of their circulatory system has to be taken into account. Therefore, extracorporeal blood volume and product volume should be small to avoid side effects. Nine children (age 2-14 years, weight 12.8-58.5 kg) with malignancies underwent 10 PPC collections with the MNC programme of the Amicus blood cell separator. The disposable kit was primed with red blood cells (RBCs) or human albumin to avoid circulatory side effects. The children were monitored for blood pressure and heart rate during the whole apheresis procedure. A median blood volume of 4,577 ml (range 3,536-8,596 ml) was processed in a separation time of 270 min (range 176-331 min). The median product weight was 81 g (range 53-107 g) and the yield of CD 34 antigen expressing cells was 12.5 x 10(6)/kg body weight (range 1.8-26 x 10(6)/kg body weight). Only one child had to undergo a second apheresis to collect the desired transplantation dose. The median platelet contamination of the product was 0.32 x 10(11) (0.13-0.85 x 10(11)). No circulatory side effects were observed. Blood flow alarms occurred in seven of ten aphereses and one collection had to be terminated due to insufficient flow. PPC can be efficiently collected in children with the MNC programme without circulatory side effects. The platelet contamination of the product was low due to the elutriation principle of the collection process, thereby avoiding thrombocytopenic bleeding episodes in the patients.