Influence of age and pathological obesity on the potential use of human adipose-derived stem cells (hASCs) in orthopaedic tissue engineering

Human adipose stem cells (hASCs) show several features, such as a multi-differentiative potential and a reduced immunogenicity, that make them suitable candidates in tissue engineering for several applications in the orthopaedic field . We believe that it is important to define some factors that may influence the ability of hASCs to grow and osteo-differentiate and which could explain some inter-donor variabilities. In order to study the influence of age and the body mass index (BMI) we have isolated hASCs from abdominal subcutaneous adipose tissue aspirated from healthy younger females (n=12, mean age 31\ub14 years, BMI40). First of all the immunophenotype of hASCs has been analyzed by FACS, and the expression of specific Mesenchymal Stem Cells markers was detected: CD34 and CD49d antigens are differently expressed in cells derived from younger and elder women, whereas the expression of CD29, CD34, CD90 and CD166 markers is modified in hASCs isolated from healthy and obese females. Next we have evaluated a different ability of hASCs to produce colonies and to osteo-differentiate. We have observed that the number of cells derived from younger women is significantly more abundant (p<0.005) respect to elder women together with a higher clonogenic potential (p