Do age and obesity affect any features of human adipose stem cells?

Introduction: Human adipose stem cells (hASCs) show osteodifferentiative potential and reduced immunogenicity that make them suitable candidates in bone-tissue-engineering. We believe that some factors such as age and body mass may influence the features of hASCs. Materials and Methods: We isolated hASCs from subcutaneous adipose tissue of healthy-young-females (n=12, mean age 31±4 years, BMI=23±1), from middle-age ones (n=14, mean age 56 ±7 years, mean BMI=26±2) and from obese-young-females (n=3, mean age 34±2 years, mean BMI=44±4) We characterized hASCs by their clonogenic ability, immunophenotype and their osteogenic potential. Moreover the cytokine profile of Peripheral Blood Leucocytes (PBL) cultured with hASCs and phytohemagglutinin (PHA) was performed by ELISA assay. Results: hASCs show a mesenchymal stem cells immunophenotype even if CD34 and CD49d antigens are differently expressed in cells derived from younger and elder women, whereas the expression of CD54, CD90 and CD166 is modified in hASCs isolated from healthy and obese-females. Next we observed that younger women show a clonogenic potential higher then elder women (p< 01) whereas hASCs derived from obese donors have a similar ability. In addiction, hASCs from younger women osteo-differentiate (p< 05) better than cells from elder and obese donors. Have we also observed that allogenic hASCs do not elicit Th1 and Th2 immuneresponse by actived PBL. Discussions: hASCs may be affected by both physiological and pathological conditions of the donors suggesting that not all the hASC’s sources are ideal for future clinical applications in bone regeneration, however their low immunogenicity may allow allogenic cells transplantation.