Characterization of peripheral blood steady-state progenitor cells preserved in liquid culture conditions with or without GM-CSF and IL2.

Abstract

The cellular characteristics of steady-state peripheral blood progenitor cell (PBPC) apheresis, including total number of lymphomononuclear cells, CD34 and CFUs, was evaluated in a group of 26 chemo-radiotherapy patients as well as in a group of 23 surgically resected cancer patients. Three-to seven-day incubation in standard liquid culture conditions with growth factors (IL2, GM-CSF or both) correlated with a statistically significant increase in CD34+ and CD56+ cell populations compared with incubation without growth factors, especially when both GM-CSF and IL2 were used. In addition, an increase in CD33+, CD13+ and HLA-DR+ cell populations was observed after 3-7 days incubation with GM-CSF. The basal culture control exhibited a decrease in CD33+ and CD13+ cell populations while CD34+ and CD56+ cell populations were maintained. These results were similar in the treated and untreated groups of patients. The infusion of GM-CSF and IL2 preincubated PBPC after intensive chemotherapy was associated with a rapid hematological recovery with a median time duration for WBC < 500/uL, WBC < 1.000/uL and platelets < 20.000/uL of 7.9 days, 14.9 days and 10.7 days respectively. We conclude that a short GM-CSF and IL2 preincubation of steady-state PBPC is associated with an increase in cell populations exhibiting the immune and progenitor cell phenotypes and correlates with an early hematological recovery after intensive chemotherapy.