Fig. 3. Applications of MSCs in the treatment of fibrotic diseases.

For pre-clinical and clinical trials of MSCs treatment, patients can either receive their own MSCs in an autologous way, or MSCs from related or not-related donors in an allogeneic way. Purified and amplified MSCs can be infused back into patients either systematically or locally. Systematic infusion includes intravenous injection (MSCs and MSC-derived factors are delivered in vein through circulation) and intradermal injection (MSCs and MSC-derived factors are delivered into the dermis, just below the epidermis). Local infusion can be achieved with direct injection of MSCs and MSC-derived factors into the sites of injury (for example, femur fracture), or transplantation of engineered MSC scaffolds to the sites of injury.