Evolution of ASC Immunophenotypical Subsets During Expansion In Vitro

Abstract

Adipose-derived stromal/stem cells (ASCs) are currently being considered for clinical use for a number of indications. In order to develop standardized clinical protocols, it is paramount to have a full characterization of the stem cell preparations. The surface marker expression of ASCs has previously been characterized in multiple studies. However, most of these studies have provided a cross-sectional description of ASCs in either earlier or later passages. In this study, we evaluate the dynamic changes of 15 different surface molecules during culture. Using multichromatic flow cytometry, ASCs from three different donors each in passages 1, 2, 4, 6, and 8 were analyzed for their co-expression of markers associated with mesenchymal stem cells, wound healing, immune regulation, ASC markers, and differentiation capacity, respectively. We confirmed that at an early stage, ASC displayed a high heterogeneity with a plethora of subpopulations, which by culturing became more homogeneous. After a few passages, virtually all ASCs expressed CD29, CD166 and CD201, in addition to canonical markers CD73, CD90, and CD105. However, even at passage 8, there were several predominant lineages that differed with respect to the expression of CD34, CD200 and CD271. Although the significance of remaining subpopulations still needs to be elucidated, our results underscore the necessity to fully characterize ASCs prior to clinical use.

Telocytes/CD34+ Stromal Cells in Pathologically Affected White Adipose Tissue

“…Indeed, the CD34 expression of these cells only occurs during early passages [ 2 , 3 , 4 , 5 ]. In successive passages, the loss of CD34 expression is followed by the acquisition of other markers, depending on culture conditions [ 2 , 3 , 4 , 5 ]. Thus, CD34+ cells adhere to culture plastic, proliferate and differentiate in several tissue components, including adipocytes, chondrocytes, osteoblasts and myocytes.…”

“…Other “non-traditional” functions, widely reviewed in different locations by Zwick et al (2017) [ 1 ], include (a) the modulation of tissue growth and regeneration by paracrine signals (e.g., progenitor signalling to hair follicles, mammary gland and bone marrow cell components), (b) participation in repair and cancer by crosstalk signalling and (c) the contribution to innate immunity in the skin and intestine by cytokines and antimicrobial peptides. In addition, human adipose tissue is an abundant and easily procured source of CD34+ adipose-derived stromal cells (ASCs) for studies in vitro and tissue engineering, which have received great attention [ 2 , 3 , 4 , 5 ].…”

Extracellular Vesicles from Adipose Tissue Stem Cells in Diabetes and Associated Cardiovascular Disease; Pathobiological Impact and Therapeutic Potential

“…Until now there has been no definitive description of the immunophenotypic characteristics of ADSCs, and other markers were added to the previously reported ones. Of those, CD34, is a hematopoietic marker that has been reported both to be positive in SVF and lose its expression with time and culture passages of ADSCs [ 37 ], or to maintain its expression even at late culture passages [ 38 ]. Traktuev showed that a population of adipose-derived adherent CD34+ cells are resident pericytes that play an important role in vascular stabilization by reciprocal interaction with endothelial cells [ 39 ].…”

Adipogenesis, Osteogenesis, and Chondrogenesis of Human Mesenchymal Stem/Stromal Cells: A Comparative Transcriptome Approach

“…On the other hand, looking for markers that were differentially expressed, it was found that CD143 (an angiotensin-converting enzyme) was highly expressed in bone marrow and adipose tissue-derived MSC in comparison with umbilical cord blood and umbilical cord-derived MSC, suggesting that this marker could differentiate MSC from adult tissues and those derived from perinatal tissues ( Amati et al, 2018 ). In relation to the influence of passage number, analysis of adipose tissue-derived MSC at passages #1 to #8 showed that they changed its immunophenotypic profile based on passage number, although some of the markers presented a variable expression independently from time ( Peng et al, 2020 ).…”