Both early and committed haemopoietic progenitors are more frequent in peripheral blood than in bone marrow during mobilization induced by high‐dose chemotherapy + G‐CSF

Abstract

Haemopoietic growth factor administration following high-dose chemotherapy markedly amplifies progenitor cell pool in the peripheral blood (PB). Collection and reinfusion of these cells enable rapid haemopoietic reconstitution following autograft. Less is known on engraftment potentiality of bone marrow (BM) cells taken under analogous conditions. To investigate this tissue, PB and BM were evaluated simultaneously during maximal mobilization in a series of 14 patients undergoing the HDS chemotherapy programme. A significantly higher growth of committed progenitors was found from PB rather than from BM (663 +/- 123 v 267 +/- 40 CFU-GM/10(5) MNC, respectively). Also, significantly more CFU-GM could be collected by a median of three leukaphereses, compared to those harvested from BM (158 +/- 31 v 16 +/- 4 x 10(4) CFU-GM/kg, respectively). Most mobilized CFU-GM were phenotypically immature (CD15-); in addition, circulating cells included primitive progenitors, as assessed by LTC-IC assay, or by evaluation of non-proliferating pre-CFU-GM, selected by an anti-CD71 immunotoxin. The amount of pre-CFU-GM determined by both techniques was consistently higher in PB than in BM. Moreover, a direct correlation could be established between circulating CFU-GM and primitive precursors. Thus, during optimally induced mobilization, PB contains many more haemopoietic progenitors, of both committed and primitive stages, than does BM. Under such conditions, PB is probably the best source of material for graft purposes.

Long-term follow-up of patients with peripheral T-cell lymphomas treated up-front with high-dose chemotherapy followed by autologous stem cell transplantation

“…13 A phycoerythrin-conjugated anti-CD34 monoclonal antibody was used (anti-HPCA-2, Becton Dickinson, Lincoln Park, NJ, USA), as described. 14 The number of circulating CD34 þ cells/ml of blood was obtained by multiplying the percentage of CD34 þ cells by the number of leucocytes in 1 ml of blood. Peripheral blood buffy-coat cells were collected when the white blood cell count was at least 1000/ml and PB CD34 þ cells 410/ml.…”

Very large amounts of peripheral blood progenitor cells eliminate severe thrombocytopenia after high-dose melphalan in advanced breast cancer patients

“…In spite of this, reassuring data have been reported by Bender et al, 21 and by our previous study that demonstrated a positive correlation between both committed progenitor cells (CFU-GM) and long-term repopulating stem cells (LTC-IC) during mobilization. 15 Furthermore, during the late phase of mobilization a higher number of nucleated cells are collected with a greater risk of tumor cell contamination. In our experience, however, patients transplanted with a higher number of CD34 + cells did not receive a higher dose of nucleated cells (Table 4).…”

“…The procedure has already been described in detail by Tarella et al 15 Briefly, myeloid progenitors (CFU-GM) were assayed in semisolid medium in the presence of: Iscove's modified Dulbecco's medium, agar 0.3%, FBS 20% and the supernatant of the 5637 cell line was used as stimulating factor. CFU-GM progenitor frequency was evaluated by plating blood samples from each apheresis before cryopreservation.…”

“…Only nine out of 21 patients required platelet support, while all patients but two needed 2 RBC unit transfusions (range 0-5). All patients experienced gastrointestinal toxicity (nausea and vomiting) and mucositis (degree I/III WHO) that persisted for 9 days (range [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Eleven patients needed opioid analgesic drugs.…”

“…The aplasia started on day +7 (range +5 to +9) after HD-L-PAM, and the WBC nadir ranged between 0.1 and 0.4 × 10 9 /l. There were 6 days (range 4-9) with leukocytopenia, and time to more than 1 × 10 9 /l leukocytes for 3 consecutive days was day +13 (range [11][12][13][14][15][16]. Median number of days with less than 20 or less than 50 × 10 9 /l platelets was 0 (range 0-3) and 3 days (range 0-7), respectively, while median time to reach more than 100 × 10 9 /l platelets was 12.5 days (range [11][12][13][14][15][16][17].…”