Fibroblast-Negative CD34-Negative Cells from Human Adipose Tissue Contain Mesodermal Precursors for Endothelial and Mesenchymal Cells

Abstract

There is considerable evidence that stem/progenitor cells reside in the vasculature during the prenatal and postnatal stages. The stromal vascular fraction (SVF) of human adipose tissue is markedly rich in blood vessels, and it is a source of mesenchymal/stromal cells (MSCs). Therefore, we hypothesized that, in addition to MSCs, the SVF may contain other mesodermal precursors. However, the SVF has a high content of CD34(+) cells with high proliferative capacity, which can prevent the growth of the most quiescent cells. By using an antifibroblast (FIB) antibody coupled to microbeads, we show that ∼ 90%-95% of the nonhematopoietic CD34(+) cells were retained in the CD45(-)FIB(+) fraction. Reverse transcription-polymerase chain reaction analysis revealed that the CD45(-)FIB(-)CD34(-) cell fraction expressed higher mRNA levels of KDR and GATA2 than its complementary CD45(-)FIB(-)CD34(+) cell fraction, which contained the SVF endothelial cells. Surprisingly, when CD45(-)FIB(-)CD34(-) cells were cultured in endothelial growth medium, they gave rise to endothelial colonies and mesenchymal colonies. Moreover, when CD45(-)FIB(-)CD34(-) cells were cultured in embryonic stem cell expansion medium, they gave rise to cells exhibiting the full range of phenotypes observed in the freshly isolated SVF, including CD34(+) and CD31(+) cells. Together, these results suggest that the CD45(-)FIB(-)CD34(-) cells within the SVF of human adipose tissue function as mesodermal precursors of mesenchymal and endothelial cells.

Differential phenotype and behavior in culture of CD34 positive cells from peripheral blood and adipose tissue

“…At 7 days in culture, cells no longer expressed CD34, but were persistently VEGFR2 positive, expressed CD31, and were also positive for eNOS expression on confocal microscopy ( Figure 1 , bottom right). These cells did not express CD45, consistent with a non-hematopoeitic phenotype, and consistent the findings of others [ 31 ]. We concluded therefore that CD34 + cells from adipose tissue were phenotypically different to those that circulate in blood and unlike those from blood, proliferate in endothelial cell culture medium, and demonstrate some features of an endothelial cell phenotype.…”

“…The paracrine effects of these cells has been described and the CD34 positive subfraction of ADSCs identified from the SVF express and secrete VEGF among other growth factors [ 29 , 30 ]. It is noteworthy that adipose derived CD34 + cells do not express CD45 [ 31 ], consistent with a non-hematopoietic lineage.…”

Necroptosis in Macrophage Foam Cells Promotes Fat Graft Fibrosis in Mice

“…In this study, the number of S100A4-positive cells (fibroblasts) was increased in fat grafts. Approximately 85% of stromal vascular fraction CD45-negative cells are anti-fibroblast (FIB)-positive cells in adipose tissue (Navarro et al, 2015), which are considered to be involved in ECM remodeling (Tanaka et al, 2014). Collagen I and collagen VI were highly expressed and their expression remained high for up to 16 weeks in fat grafts relative to before grafting.…”

Comparative Analysis of Stromal Vascular Fraction and Alternative Mechanisms in Bone Fracture Stimulation to Bridge the Gap between Nature and Technological Advancement: A Systematic Review

“…Secondly, SVF's ability to modulate biomarkers associated with bone regeneration, as highlighted in Table 1, showcases its potential to influence healing processes at a molecular level. This precision in targeting key factors involved in bone repair can result in superior and more predictable outcomes [69]. In comparison to other bone healing methods like electrical stimulation, ultrasound stimulation, and mechanical stimulation, SVF offers a unique advantage through its ability to address multiple facets of the healing process at the molecular level.…”