Immunomodulatory effect of human adipose tissue‐derived adult stem cells: comparison with bone marrow mesenchymal stem cells

TLDR

Adipose tissue–derived adult stem cells (ADAS) can differentiate into multiple lineages and, like bone marrow mesenchymal stem cells, hold therapeutic potential for tissue repair, with allogenic use possible if graft tolerance is achieved. This study compares the immunosuppressive properties of ADAS cells to those of well‑characterized bone marrow mesenchymal stem cells. ADAS cells suppress alloreactive lymphocytes, inhibit mixed lymphocyte reactions and mitogen‑stimulated proliferation, require direct cell contact for full inhibition, and exhibit immunosuppressive effects comparable to BM‑MSCs, indicating their suitability as an alternative allogenic therapeutic source.

Abstract

Summary Like mesenchymal stem cells from bone marrow (BM‐MSCs), adipose tissue‐derived adult stem cells (ADAS cells) can differentiate into several lineages and present therapeutical potential for repairing damaged tissues. The use of allogenic stem cells can enlarge their therapeutical interest, provided that the grafted cells could be tolerated. We investigate here, for the first time, the immunosuppressive properties of ADAS cells compared with the well‐characterized immunosuppressive properties of BM‐MSCs. ADAS cells did not provoke in vitro alloreactivity of incompatible lymphocytes and, moreover, suppressed mixed lymphocyte reaction (MLR) and lymphocyte proliferative response to mitogens. The impairment of inhibition when ADAS cells and BM‐MSCs were separated from lymphocytes by a permeable membrane suggests that cell contact is required for a full inhibitory effect. Hepatocyte growth factor is secreted by both stem cells but, similar to interleukin‐10 and transforming growth factor‐ β (TGF‐ β ), the levels of which were undetectable in supernatants of MLR inhibited by ADAS cells or BM‐MSCs, it did not seem implicated in the stem cell suppressive effect. These findings support that ADAS cells share immunosuppressive properties with BM‐MSCs. Therefore, ADAS cell‐based reconstructive therapy could employ allogenic cells and because of their immunosuppressive properties, ADAS cells could be an alternative source to BM‐MSCs to treat allogenic conflicts.