Peripheral blood progenitor cells harvesting

Hypocalcemia is the result of alterations in the effect of parathyroid hormone and vitamin D on the bone, gut, and kidney (see Fig. 49-9). The primary causes of hypocalcemia are postoperative hypoparathyroidism and vitamin D deficiency. Other causes include magnesium deficiency, thyroid surgery, medications, hypoalbuminemia, blood transfusions, peripheral blood progenitor cell harvesting, tumor lysis syndrome, and mutations in the calcium-sensing receptor. " Parathyroid hormone concentrations are elevated in conditions of hypocalcemia, with the exception of hypoparathyroidism and hypomagnesemia (Fig. 49-11). ... 

Kishimoto M, Ohto H, Shikama Y, et al. Treatment for the decline of ionized calciumlevels during peripheral blood progenitor cell harvesting. Transfusion 2002 42 1340-1347. 

Sato N, Sawada K, Takahashi TA, et al. A time course study for optimal harvest of peripheral blood progenitor cells by granulocyte colony-stimulating factor in healthy volunteers. Exp Hematol 1994 22 973-978. 

E. Therapentic response In clinical trials Leukine was safe and effective in adult patients with acute myeloid leukemia, reducing the duration of neutropenia as well as chemotherapy-associated mortality and morbidity. Leukine, administered alone or after myeloablative chemotherapy, enhances the number of circulating peripheral blood progenitor cells, allowing harvest for autologous transplantation. 

Prior to peripheral blood stem cell harvesting, however, the stem cells must be mobilized or stimulated to enter the peripheral blood. The mobilization process is set into motion by stressing neutrophils and osteoclasts into activity by the use of cytokines with, or without chemotherapy. This results in the shedding and release of membrane-bound stem cell factor (SCF), proliferation of progenitor cells and activation or degradation of various adhesion molecules. Stem cells can be mobilized to enter the peripheral... 

Assessment of the progenitor cell content in bone marrow (BM) and peripheral blood stem cell (PBSC) harvests... 

Unlike BM harvests the success of PBSC harvesting depends on mobilization of progenitor cells into the peripheral blood with cytotoxic agents and/or cytokines. This is influenced by the age of the patient and the duration and type of previous chemotherapy. Among the elderly (> 65 years) and those who have previous treatment with aUylating agents or radiation, mobilization can be severely impaired (5). 

For clinical and research applications, there are three main sources of human HSCs bone marrow, G-CSF mobilized peripheral blood, and umbilical cord blood (UCB). For clinical purposes, harvests of marrow, mobilized blood, or UCB may be enriched for HSPCs by CD34 (Civin et al. 1996). Such clinical HSPC preparations are a heterogeneous population composed mainly of progenitor cells along with <1% HSCs. 

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