An Evaluation of the Stemness, Paracrine, and Tumorigenic Characteristics of Highly Expanded, Minimally Passaged Adipose-Derived Stem Cells

Abstract

The use of adipose-derived stem cells (ADSC) in regenerative medicine is rising due to their plasticity, capacity of differentiation and paracrine and trophic effects. Despite the large number of cells obtained from adipose tissue, it is usually not enough for therapeutic purposes for many diseases or cosmetic procedures. Thus, there is the need for culturing and expanding cells in-vitro for several weeks remain. Our aim is to investigate if long- term proliferation with minimal passaging will affect the stemness, paracrine secretions and carcinogenesis markers of ADSC. The immunophenotypic properties and aldehyde dehydrogenase (ALDH) activity of the initial stromal vascular fraction (SVF) and serially passaged ADSC were observed by flow cytometry. In parallel, the telomerase activity and the relative expression of oncogenes and tumor suppressor genes were assessed by q-PCR. We also assessed the cytokine secretion profile of passaged ADSC by an ELISA. The expanded ADSC retain their morphological and phenotypical characteristics. These cells maintained in culture for up to 12 weeks until P4, possessed stable telomerase and ALDH activity, without having a TP53 mutation. Furthermore, the relative expression levels of TP53, RB, and MDM2 were not affected while the relative expression of c-Myc decreased significantly. Finally, the levels of the secretions of PGE2, STC1, and TIMP2 were not affected but the levels of IL-6, VEGF, and TIMP 1 significantly decreased at P2. Our results suggest that the expansion of passaged ADSC does not affect the differentiation capacity of stem cells and does not confer a cancerous state or capacity in vitro to the cells.

Phenotypic characterization and differentiation of mesenchymal stem cells originating from adipose tissue

“…In our study, we showed that expression patterns of cell surface markers on P3 cells were associated with MSCs [28][29][30]. El Atat et al [31] reported that ADSCs displaying CD90 and CD105 expressions were able to adhere to plastic surfaces under in vitro culture conditions. Moreover, these markers have also been used to determine multilineage differentiation capabilities of ADSCs [30].…”

Effect of adipose-derived mesenchymal stem cells on hepatocellular carcinoma: In vitro inhibition of carcinogenesis

“…Multilineage differentiation of ADMSCs: ADMSCs showed a differentiation capacity to become adipocytes, osteocytes, and chondrocytes. Adipogenic differentiation, osteogenic differentiation and chondrogenic differentiation was performed as previously described[24].…”

Ex-Vivo Stimulation of Adipose Stem Cells by Growth Factors and Fibrin-Hydrogel Assisted Delivery Strategies for Treating Nerve Gap-Injuries

“…Adipose-derived stem cells (ASC) are easily accessible in large quantities from fat-tissue enabled by liposuction or abdominoplasty [ 6 , 13 , 16 ]. ASC proliferate rapidly [ 6 ] and possess a multi-lineage capacity, i.e., adipocytes, osteoblasts, chondrocytes [ 13 , 17 , 18 ]. Furthermore, ASC retain their mesenchymal potency over long-term culture [ 6 , 18 ] and promote the nerve regeneration similar to bone marrow stem cells [ 7 ].…”

“…ASC proliferate rapidly [ 6 ] and possess a multi-lineage capacity, i.e., adipocytes, osteoblasts, chondrocytes [ 13 , 17 , 18 ]. Furthermore, ASC retain their mesenchymal potency over long-term culture [ 6 , 18 ] and promote the nerve regeneration similar to bone marrow stem cells [ 7 ]. In allogeneic transplantation, usage of ASC, like any other adult stem cells, benefits from their hypo-immunogenicity or immune-privilege by virtue of the reduced expression of HLA-DR class II histocompatibility antigen [ 19 , 20 ].…”