Stem Cell Secretome for Skincare: Of Cell Types, Exosomes, Extracellular Vesicles, and Soluble Fractions

Considering adipose-, bone marrow-, and umbilical cord-mesenchymal stem cells, adipose mesenchymal stem cells (ADSCs) have evolved to arise in the skin during the third trimester of fetal development, while the other two arise in tissues other than the skin. The ADSCs, located in the hypodermis and reticular dermis, arise just before birth so that they can be present following birth to dampen inflammation that may arise in the baby’s new hostile, non-sterile environment where the skin is under constant insult from injuries, toxins, UV, antigens, allergens (triggers of IgE), and pathogens. ADSCs and the molecules they release are preferred over, 1. bone marrow mesenchymal stem cells and platelets, which serve to induce inflammation and rapid fibrotic scarring, and 2. over umbilical cord mesenchymal stem cells, that have evolved to operate in the sterile conditions of the womb to form the cord, which is unlike skin structure and function, and since it’s a sterile environment, not dampen inflammation which is unneeded and doesn’t happen in the sterile environment where infection can’t happen. The molecules released from ADSCs, and found in the soluble fraction, exosomes, ectosomes, and larger EVs such as blebbisomes, have been found to be the safest and most effective stem cell released molecules to use as skin therapeutics, with a consistent set of molecules across donors.