Peripheral blood stem cell harvest in Saudi Arabia. A review of the first decade

Abstract

The possible use of marrow progenitor cells derived from peripheral blood was hypothesized almost 30 years ago 1 and confirmed two decades later with the first efforts to collect and preserve human stem cells from peripheral blood during remission after chemotherapy for hematological malignancy. 2,3 During the past 10 years the use of autologous progenitor cells mobilized to the peripheral blood has gradually replaced the use of autologous bone marrow due to certain obvious advantages such as ease of collection, avoidance of general anesthesia, low contamination with malignant cells, and a shorter cytopenic phase. The latter is due to the presence of large numbers of lineage committed cells. 4 While progenitor cells are present in peripheral blood in very low numbers in the steady state, chemotherapy 5 and, recently, chemotherapy in combination with recombinant growth factors 6 have been shown to effectively increase the level of stem cells peripherally. Post-harvest cell cultures have traditionally been used to evaluate the number of committed cells in the hemapheresis product, 7 with the obvious drawback of a 14-day delay in laboratory results. With the advent of flow cytometry which permits rapid assessment of progenitor cell numbers as expressed by CD34+ve cells 8 it is now possible to schedule peripheral blood stem cell harvests (PBSCHs) to coincide with the peak level of circulating stem cells.