Anti-Inflammatory Properties of Mesenchymal Stem Cells

Goals/Purpose: Clinical outcomes in adipose tissue transfer are dependent on several factors, which can lead to cell death, fat necrosis, resorption and fibrosis.  With the discovery of mesenchymal stem cells (MSCs) within adipose tissue there has been increasing interest in using these cells for their anti-inflammatory and regenerative properties for fat transfer.  The purpose of this study was to isolate MSCs from breast and abdominal adipose tissue and compare the immunomodulatory properties that may play a role in healing following fat transfer. 

Methods/Technique: Breast and abdominal tissues were obtained from healthy donors based on approved protocols.  MSCS were isolated according to established protocols.  Cells were characterized as MSCS according to standard surface markers and differentiation capabilities.  RNA expression of fibroblast growth factors and receptors were compared in culture expanded cell lines.  Additionally, MSCs were co-cultured with peripheral blood monocytes according to established protocols and compared for macrophage immunophenotype and RNA expression.

Results/Complications:  MSCs isolated from breast and abdominal tissue were uniformly positive for established mesenchymal surface markers (CD29, CD 44, CD73, CD90 and CD105) and negative for hematopoietic markers (CD14, CD 34, and CD45).  MSCs demonstrated ability to differentiate into bone, adipose and cartilage.  FGF and FGFR expression was the same in breast and abdominal derived MSCs.  Following 7 days of co-culture, macrophages displayed surface markers consistent with an anti-inflammatory phenotype (increased CD206, decreased HLA-DR and CD16) compared to control macrophages.  Further, macrophages cocultured with MSCs had higher expression of proteins important to inflammation and wound healing (serpine1 and osteopontin, p<0.05) compared to control cells. 

Conclusion: Recent work has shown that MSCs isolated from different tissue sources may have different immunomodulatory or reparative properties, though the clinical significance of this observation has yet to be determined.   Our work further supports the potentially vital role of MSCs in adipose tissue transfer.