REVIEW: Conditioned Medium of Mesenchymal Stromal Cells: A New Class of Therapeutics

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N. V. Bogatcheva^1,a* and M. E. Coleman^2,b

¹Division of Pulmonary and Critical Care, Department of Medicine, Indiana University School of Medicine, IUPUI, Indianapolis, IN 46202, USA

²Theratome Bio, Inc., Indianapolis, IN 46202, USA

^* To whom correspondence should be addressed.

Received June 2, 2019; Revised July 17, 2019; Accepted July 17, 2019

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Mesenchymal stromal cell (MSCs) represent a class of biologics with the prospects for employment as immunomodulatory, tissue-protective, and regenerative therapeutics. In parallel with cellular therapy, cell-free therapy based on MSC-secreted bioactive factors is being actively developed. MSCs secrete a variety of protein, peptide, RNA, and lipid mediators which can be concentrated, frozen, or even lyophilized without loss of activity, which gives them a certain advantage over cellular products requiring liquid nitrogen storage and infrastructure to revive frozen cells. This review (i) describes currently conducted clinical trials of cell-free products containing MSC secretome; (ii) summarizes main approaches to the generation and characterization of conditioned media concentrates and extracellular vesicle isolates; (iii) analyzes a variety of preclinical studies where effectiveness of secretome products has been shown; and (iv) summarizes current knowledge about secretome bioactive components obtained by analysis of in vivo models testing the therapeutic potential of the MSC secretome.

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KEY WORDS: MSC, secretome, conditioned media, extracellular vesicles, exosomes

DOI: 10.1134/S0006297919110129

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