Autologous recellularization of decellularized heart valve scaffolds is a promising challenge in the field of tissue-engineered heart valves and could be boosted by bone marrow progenitor cell mobilization.
We used unfractionated PBMC obtained from ∼1 ml of peripheral blood of ordinary blood donors in the absence of bone marrow stem cell mobilization or of ex vivo priming of any other type, and selectively expanded the contained stem cells by in vitro culture in the presence of a defined combination of growth factors favouring erythropoietic commitment and expansion [7].
This suggests that distinct mechanisms may be responsible for the recruitment of each population and argues against a generalized alteration in marrow-derived cell mobilization or trafficking.
Such disequilibrium would favor the proliferation and mobilization of pathological stem cells including hematopoietic, mesenchymal and endothelial stem/progenitor cells from the bone marrow to the blood, leading to bone marrow aplasia and stem cell mobilization.
It plays an important role in wound-healing [ 20], inhibiting plasmin and activating plasminogen and thrombin, and also inhibits haematopoietic stem cell mobilization in bone marrow [ 45].
This study was designed to investigate whether the inhibition of eosinophil influx to the lung of allergic rats reflects modifications in the pattern of cell mobilization from the bone marrow to peripheral blood and/or to lung.
In fact, stromal-derived factor (SDF-1) and VEGF favor the arrest of progenitors on the vascular endothelium, whereas interleukin-8 (IL-8) promotes stem cell mobilization from the bone marrow.
Our results support that, by repressing CXCL12 expression and inducing CXCR4 expression, the growth factor regulation of CXCL12 signaling could trigger these effects, as was observed during stem cell mobilization from the bone marrow to peripheral blood [ 43].
Thirdly, because SDF1α functions as a chemoattractant for stem/progenitor cells, the SDF1α gradient between bone marrow, peripheral blood and injured tissue/sites is crucial for stem/progenitor cell mobilization, differentiation and homing[26], [34] [36].
CXCR4-CXCL12 inhibition mobilizes marrow cells, and the CXCR4 inhibitor plerixafor is FDA approved for stem cell mobilization in non-Hodgkin's lymphoma and multiple myeloma prior to autologous SCT.
