Potency Analysis of Mesenchymal Stromal Cells Using a Phospho-STAT Matrix Loop Analytical Approach

• Type of Material: Article
• Authors: Raghavan Chinnadurai, Emory University; Augustine Rajakumar, Emory University; Andrew J. Schneider, University of Wisconsin; Wade A. Bushman, University of Wisconsin; Peiman Hematti, University of Wisconsin; Jacques Galipeau, University of Wisconsin
• Language: English
• Date: 2019-08-01
• Publisher: Wiley
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © AlphaMed Press 2019.
• Final Published Version (URL): http://dx.doi.org/10.1002/stem.3035
• Title of Journal or Parent Work: Stem Cells
• Volume: 37
• Issue: 8
• Start Page: 1119
• End Page: 1125
• Grant/Funding Information: This work was supported by National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases award R01DK109508 to JG.; This project is supported in part by a grant from the When Everyone Survives Foundation to R.C.; This study is also supported by University of Wisconsin Carbone Cancer Center Support Grant P30 CA014520.
• Keywords: Interferon gamma; Cell Biology; Life Sciences & Biomedicine; Biotechnology & Applied Microbiology; Assay matrix; Potency analysis; Phosflow; Hematology; Assay; Immune suppression; Science & Technology; International society; Phospho-STAT; Oncology; Cell & Tissue Engineering; Mesenchymal stromal cells
• Research Categories: Health Sciences, Oncology; Biology, Cell; Biology, Microbiology

Abstract

Potency assays for mesenchymal stromal cells (MSCs) need to be defined in advanced clinical trials. Here, we have developed an assay matrix approach that captures the signal transducer and activator of transcription (STAT) phosphorylation of MSCs upon stimulation with their combined secretome that arose with the interaction of activated peripheral blood mononuclear cells (PBMCs). Secretome of heat-inactivated (HI) MSCs cocultured with and without activated PBMCs was used as an internal reference. We have compared the short-term phosphorylation status of STAT1, STAT3, STAT4, STAT5, and STAT6 on MSCs derived from human bone marrow, adipose tissue, and umbilical cord using phosflow technology. Secretome of live MSCs cocultured with activated PBMCs downregulate STAT1 and STAT3 phosphorylation on MSCs, whereas the secretome of HI-MSCs or PBMCs do not. Thus, investigation of the combined secretome of MSC and PBMC interaction on MSCs determine the potency of MSCs as the generator and sensor of the secretome. Bone marrow, adipose, and umbilical cord MSCs are comparable in modulating STAT1 and STAT3 responses. Measurements of STAT1 and STAT3 phosphorylation on MSCs as responder cells correlate and predict allogeneic T-cell suppression. Our comparative phosphomatrix approach between live and reference HI-MSCs defines the potency of MSCs as both stimulators and responders as part of a robust platform for predictive potency analysis. Stem Cells 2019;37:1119–1125.