Читать книгу Transfusion Medicine - Jeffrey McCullough - Страница 185
Quality control of peripheral blood stem cell concentrates
ОглавлениеBecause there is no definitive test for the primordial hematopoietic stem cell, quality control of these PBSC concentrates is not standardized. Cell culture techniques can be used to determine CFU‐GM, BFU‐E, and CFU‐MIX colonies, and the number of CD34+ cells can be determined by flow cytometry. In practice, the dose for transplantation is usually based on cell counting to obtain at least 3 × 108 mononuclear or 5 × 106 CD34+ cells per kilogram of the recipient’s body weight. The results of progenitor assays are not available for about 2 weeks and thus can be used only in retrospect for research purposes. Many centers do not even determine progenitor content because they do not believe there is a correlation with engraftment, although we believe this can be a valuable quality‐control test.
Table 6.3 Effects of 10 μg/kg G‐CSF dose on the quantity of cells collected by one apheresis procedure from healthy people treated with G‐CSF for 5 days (number of cells collected).
Source: Stroncek DF, Clay ME, Smith J, et al. Composition of peripheral blood progenitor cell components collected from healthy donors. Transfusion 1997; 37:411–417. © 1997 John Wiley & Sons. Reproduced with permission of John Wiley & Sons.
| All components (n = 150) | |||
|---|---|---|---|
| Cell type | Mean ± SD | Median | Range |
| WBCs (× 109) | 39.8 ± 21.8 | 36.0 | 15.6–163.3 |
| MNCs (× 109) | 38.1 ± 19.4 | 34.5 | 15.6–139.7 |
| CD34+ cells (× 108) | 452 ± 294 | 383 | 78–1,380 |
| CD34+ cells (× 106 per L processed) | 53.2 ± 33.1 | 46.5 | 9.3–146.3 |
| RBC (mL) | 7.2 ± 3.5 | 7.6 | 0–15.5 |
| Neutrophils (× 109) | 1.77 ± 3.37 | 1.05 | 0–23.68 |
| Platelets (× 1011) | 490 ± 100 | 490 | 250–740 |
MNC, mononuclear cell; RBC, red blood cell; WBC, white blood cell.
Table 6.4 Quantity of cells in the PBSC components.
Source: Stroncek DF, Clay ME, Smith J, et al. Comparison of two blood cell separators in collecting peripheral blood stem cell components. Transfus Med 1997; 7:95–99. © 1997 John Wiley & Sons. Reproduced with permission of John Wiley & Sons.
| Cell type | CS‐3000 (n = 15) | Spectra (n = 14) | P |
|---|---|---|---|
| WBCs (× 109) | 40.9 ± 21.7 | 33.1 ± 10.7 | 0.24 |
| Neutrophils (× 109) | 1.38 ± 1.88 | 5.53 ± 8.71 | 0.001 |
| Mononuclear cells (× 109) | 39.6 ± 21.9 | 26.9 ± 5.6 | 0.02 |
| Platelets (× 109) | 507 ± 98 | 531 ± 116 | 0.54 |
| CD34+ cells (× 106) | 470 ± 353 | 419 ± 351 | 0.69 |
WBC, white blood cell.
There is considerable variation in the number of CD34+ cells collected (Figure 6.3). In our early experience [115], a single‐cytapheresis procedure yielded a median dose of 780–1,658 × 106 CD34+ cells. In approximately 42% of the procedures, this would be an adequate cell dose to transplant 5 × 106 CD34+ cells/kg to a 75‐kg recipient.
In 86% of donors, two cytapheresis procedures would yield an adequate cell dose for transplanting the 75‐kg recipient. These numbers were obtained by processing approximately 10 L of whole blood, and most centers now process 15–20 L. Other reports involving processing of 15–20 L of blood for each cytapheresis procedure suggest that larger numbers of CD34+ cells are obtained [114]. Thus, currently for most donors, one or two procedures result in a dose of cells suitable for transplantation.
