Stem cells harvesting from peripheral blood

Various designs of cell separators have been used since the technique of stem cell harvesting from peripheral blood first became an option. In the main, these have relied upon the principle of... 

The success of transplantation with peripheral blood stem cells depends upon infusion of adequate numbers of hematopoietic stem cells. Administration of G-CSF to the donor (in the case of autologous transplantation, the patient who also will be the recipient of the transplantation) greatly increases the number of hematopoietic stem cells harvested from the donor s blood and available for the transplantation procedure. The answer is (B). 

Stem Cell Transplant. Stem cells can be found in either the bone marrow or the peripheral circulating blood. They also can be found in umbilical cord blood and fetal marrow and liver. Before stem cells can be harvested from a donor, mobilization of stem cells into the peripheral blood is stimulated by the use of cytokines. A process called apheresis is used to collect the stem cells from the donor s blood. These harvested stem cells are then injected into the patient. As with a bone marrow transplant, it is also possible to perform an autologous stem cell transplant. The transplanted patient will usually begin to produce new blood cells ten to twenty-one days after receiving the harvested stem cells. 

Stem cell therapy involves infusion of specialized cells utilized to perform specific functions. The traditional use of cell therapy includes harvest and cryopreservation of autologous hematopoietic cells either from the bone marrow (old approach) or mobilization and pheresis of hematopoietic stem cells from peripheral blood using stem cell-mobilizing cytokines such as hematopoietic colony-stimulating factors (G-CSF, GM-CSF) or chemokine inhibitors (AMD-3100). A more recent stem cell source is umbilical cord blood that has rich pleuripotent potential and can engraft at lower doses than bone marrow or mobilized peripheral blood stem cells. 

Autologous hematopoietic stem cells are obtained (or harvested ) from bone marrow or peripheral blood. The technique for harvesting autologous hematopoietic cells depends on the anatomic source (i.e., bone marrow or peripheral blood). A surgical procedure is necessary for obtaining bone marrow. Multiple aspirations of marrow are obtained from the anterior and posterior iliac crests until a volume with a sufficient number of hematopoietic cells is collected (i.e., 600-1200 mL of bone marrow). The bone marrow then is processed to remove fat or marrow emboli and usually is infused intravenously into the patient like a blood transfusion. 

The bone marrow is not the only source of hematopoietic stem cells. Such cells are present in low numbers in peripheral blood, and these can be expanded in number with specific factors. Peripheral blood stem cells have the major therapeutic advantage that their harvest is relatively painless and less invasive. Likewise, umbilical cord stem cells can also be obtained in a non-invasive manner from... 

In addition to bone marrow and peripheral blood, hematopoietic stem cells are also found in umbihcal cord blood (UCB). UCB is an attractive source for several reasons. Because the stem cells are collected from placental blood, there is no risk to the mother or the baby. There is also very low risk of hansmissible infectious diseases such as cytomegalovhus and Epstein-Barr virus. In addition, the cells are available immediately because the donor does not have to be located and harvested. Initially, UCB was obtained from sibhngs but now recipients of transplants from unrelated donors accountfor almost all patients who receive UCB transplants. It is estimated that more than 2,000 unrelated UCB transplants have been performed worldwide. ... 

Bone marrow was harvested from adult male mice and then transplanted into Isogeneic female recipient mice that had been treated with a level of irradiation sufficient to destroy their own hematopoetic stem cells (see the figure). Although the dose of irradiation given was lethal to mice that did not receive a transplant, the majority of the recipient mice receiving the transplant survived. After 4 weeks, peripheral blood from the recipient mice was analyzed. The composition of the blood was normal with respect to all blood cell types. Every blood cell examined was determined to be positive for the presence of the Y chromosome. 

Figure 1 Forward scatter (FSC) and right-hand scatter (RHS) from (a) peripheral blood stem cell, and (b) bone marrow harvests.

The filtered, standardized, whole aqueous extract of the stem of Tinospora cordifolia was found to stimulate polymorphonuclear (PMN) cell function when incubated in vitro. PMN leucocytes were harvested from the peripheral venous blood of healthy volunteers, patients with obstructive jaundice and patients with tuberculosis. 1 X 10 PMN cells were incubated at 37° C for 1 h with 0.2, 0.4 and 0.8 mg/ml of Tinospora cordifolia (along with the same number of Staphylococcus aureus (in the case of healthy volunteers and patients with obstructive jaundice), or Candida... 

Collecting peripheral blood stem cell (PBSC) harvests for CD34+ quantitation 378 Collecting bone marrow (BM) harvests for CD34+ quantitation 379 Quantitation of purified CD34 cells from PBSC harvests fix>m patients with chronic lymphocytic leukaemia 382... 

Success for forming vessel networks in vivo has also been demonstrated using EPCs from human peripheral blood (Fuchs et al., 2009) particularly to address ischemia (Kawamoto et al, 2001, Kalka et al., 2000). Another source of adult stem cells that has similar proliferative potential but requires less invasive harvesting methods are adipose-derived stem cells from adipose stroma. These cells have demonstrated promising preclinical potential by differentiating into ECs and contributing to neovascularization upon implantation for the treatment of ischemia (Gao et al, 2005b, Miranville et al., 2004). 

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