Expression of mixed lymphocyte reaction class I/II and costimulatory molecules on adipose tissue stromal/stem cells (ASCs) following IFN-γ treatment. Human leukocyte antigen D-related (HLA-DR) expression on the surface of ASCs following interferon-gamma (IFN-γ) treatment under (a) ambient (21% O2) conditions and (b) low (5% O2) culture conditions for 5 days. (c, d, and e) Expression of costimulatory molecules CD40, CD80, and CD86, respectively, on ASCs under ambient and low O2 culture conditions. (f) Quantification of flow analyses following ASC culture under low or ambient O2 culture conditions. Three independent sets of experiments were performed. Data are reported as mean (μ)±standard error (SE). ***P<0.0001 comparing HLA-DR expression in an unstimulated ASC to IFN-γ-stimulated ASC, &P<0.05 comparing HLA-DR expression in ASCs under low O2 to ambient O2.