PBPC collection techniques: standard versus large volume leukapheresis (LVL) in donors and in patients

Transplantations of autologous and allogeneic peripheral blood progenitor cells (PBPC) are able to assure a complete hematopoietic and immunologic reconstitution in patients. PBPC are collected by leukapheresis technique after prior mobilization therapy, but procedures and results remain still highly variable and are poorly characterized. An optimum regimen for PBPC collections has not yet been recommended, but 2–3 total blood volumes (TBV) of the donor or patient are regarded as a standard. Another promising technique is large volume leukapheresis (LVL) with processing of 3–6 TBV of donor or patient. The aim of this paper is to find the most efficient and safe collection technique for an individual donor or patient and, consequently minimize the number of procedures required. Finding the optimal collection procedure would be helpful while considering which method would be preferred in an individual donor or patient with respect to the result of mobilization, health state and required yield of CD 34+ cells for transplantation. We evaluated the results in a total of 134 standard and LVL procedures, which were performed in 21 well mobilized donors (Group I), in 65 well mobilized patients (Group II), and in 14 weakly mobilized patients (Group III) with hemato-oncological diseases. A precollection concentration of CD 34+ cells in peripheral blood higher than 20 × 10 3/mL was considered to be the criterion for efficient mobilization. Such levels of concentration indicating the start of PBPC collections could be easily reached in Group I of donors and Group II of well mobilized patients. Heavily pretreated patients at advanced stages of disease (Group III) did not respond to mobilization sufficiently and had a concentration of CD 34+ cells lower than 20 × 10 3/mL. LVL technique made it possible to obtain higher numbers of CD 34+ cells than in the standard collection in well mobilized donors (Group I), well mobilized patients (Group II), and even in weakly mobilized patients in Group III. In donors and well mobilized patients (Group I and Group II) it was possible to collect sufficient amounts of CD 34+ cells for allogeneic or for autologous transplantation from one LVL collection. The median yield of CD 34+ cells from one LVL collection was 5.5 × 10 6/kg b.w. in donors, and 6.0 × 10 6/kg b.w. in well mobilized patients. Due to the linear dependence of the yield of collected CD 34+ cells on the concentration of CD 34+ cells in blood, it can be used as a simple pr