I want to differentiate MSC in the tri lineage tissues in an in vitro system. May I use human insuline to differentiate those cells in adipogenic tissue?
Yes, you can definitely use human insulin on human derived primary cultures and it's a universal rule that human derived products are better suited to human cultures than those derived from animals (in clinical trials we always prefer human FBS) but due to scarcity associated with human products, we rely on animals. So, until and unless it is not associated with any immunogenic reaction human products can be used for human cell culture.