Perspectives for Clinical Translation of Adipose Stromal/Stem Cells

Abstract

Adipose stromal/stem cells (ASCs) are an ideal cell type for regenerative medicine applications, as they can easily be harvested from adipose tissue in large quantities. ASCs have excellent proliferation, differentiation, and immunoregulatory capacities that have been demonstrated in numerous studies. Great interest and investment have been placed in efforts to exploit the allogeneic use and immunomodulatory and anti-inflammatory effects of ASCs. However, bridging the gap between in vitro and in vivo studies and moving into clinical practice remain a challenge. For the clinical translation of ASCs, several issues must be considered, including how to characterise such a heterogenic cell population and how to ensure their safety and efficacy. This review explores the different phases of in vitro and preclinical ASC characterisation and describes the development of appropriate potency assays. In addition, good manufacturing practice requirements are discussed, and cell-based medicinal products holding marketing authorisation in the European Union are reviewed. Moreover, the current status of clinical trials applying ASCs and the patent landscape in the field of ASC research are presented. Overall, this review highlights the applicability of ASCs for clinical cell therapies and discusses their potential.

Figure 1

Cell populations in stromal vascular fraction (SVF) [14]. The SVF contains a heterogeneous mesenchymal cell population, e.g., cells of endothelial, hematopoietic, and pericytic origin, among others. Cells of hematopoietic origin include granulocytes (15%), monocytes (15%), lymphocytes (15%), and stem and progenitor cells (<0.1%). Additionally, endothelial cells (20%), pericytes (50%), and stromal cells (30%) are found in SVF.

Figure 2

A total number of 282 clinical trials using ASC were ongoing on the 11th of September 2018, based on http://www.clinicaltrials.gov. Clinical studies were categorized based on the disease or target tissue of the treatment. Only 13 out of 282 trials had progressed into phase III or IV. A commercial sponsor was involved in 116 trials.

Figure 3

Required steps during clinical translation of ASCs.