rHIV-pWPT-EF1-a-GFP-W lentiviral vector modification does not affect msc viability or differentiation potential. (A) Evaluation of rHIV-pWPT-EF1-a-GFP-W vector toxicity on rMSC viability by MTT assay. (B) Representative images (magnification 20X) of non-induced control MSCs and MSCs induced towards the adipogenic pathway (i) non-transduced, (ii) rHIV-pWPT-EF1-a-GFP-W transduced (MOI 100) MSCs. (C) Oil red O positive cells per microscope field (number of differentiated cells). (D) Oil red O quantitation. Data are presented as mean ±SD (n = 5) or as representative images of three independent experiments.