This is a rather technical read. It was written for me by a writer for a medical communications company, initials KD, with over 25 years of experience in medical research, first at a medical school, then at two pharmaceutical companies. She has a degree in Biomedical Science, and has agreed to help explain exactly how a single foreskin can become a thousand vials of face cream. She has asked that I redact her name, because of intactivists prior contacting of people’s work, attempting to get people fired, along with harassment , threats of rape and threats on their very lives. Because of this, I have agreed to list this only under her initials and credentials
Before everything, of course, there is a circumcision. The parents give their informed consent, both for the procedure, and the acquisition of the foreskin for production of fibroblasts. A single foreskin can produce thousands of cells, and those cells can produce thousands more. This is an original article. I should mention that this addresses face creams. Fibroblasts from foreskins are also used to produce skin grafts for people who were severely injured, and for medical research.
The vast majority of the dermis layer of skin is made up of connective tissue, such as collagen. The dermis also contains nerves, blood vessels, and cells (fibroblasts). The fibroblasts produce collagen and extracellular matrix, along with growth factors that promote cell growth and differentiation.
To harvest fibroblasts from a piece of skin, the tissue is soaked in an antibiotic solution, and then minced with scissors or a razor blade. (The subsequent steps of this procedure are performed in a tissue culture hood to minimize contamination.) The minced tissue is placed in a solution of enzymes to separate the cells from the connective tissue, and then centrifuged and/or filtered through mesh to separate the cells from the rest of the non-cellular material. The cells are washed with saline solution, then resuspended in an artificial growth medium containing amino acids, vitamins, growth factors, and other nutrients. The cells are placed in one or more tissue culture plates.
This is called the “primary” culture. Over a period of several hours, the cells attach to the bottom of the plates. The cells are placed in an incubator at 37c, 95% air, and 5% CO2. The medium is replaced every few days. The cells divide at an exponential rate, with the number doubling every 12-24 hours. Once the cells almost cover the bottom of the plate, the cells are washed in saline, and treated with an enzyme (usually trypsin) to cause them to release their attachments to the plate. They can then be divided into multiple new plates, with the cells from one primary culture able to seed anywhere from a few to thousands of new plates. Each iteration of this process is called passaging. Fibroblasts from normal newborn skin can be passaged many times until division begins to slow down, the cells begin to differentiate, and eventually they cease dividing. (These cells can also be “immortalized” in a number of different ways. They are then considered to be “transformed” and can divide indefinitely. Traditionally, transformation was achieved by incubation of the cells with certain viruses, but there are now other ways this can be achieved.)
A single piece of tissue can generate millions and millions of cells. Kind of like a cutting from a plant can make an entire tree – over and over again.
The used culture medium, also called “human fibroblast conditioned medium,” collected from the cells, contains growth factors, collagen, and other nutrients produced by the fibroblasts. This medium is collected and purified, then can be added to cosmetic products. There is some debate as to the effectiveness of these factors applied to intact adult skin. However, there aren’t any actual cells in these cosmetic products. A single skin sample could generate thousands of separate cultures, each culture generating conditioned medium every couple of days, thus generating countless vials of face cream.
*This post was edited to remove a typo, and to include the points that this post is about face creams, while the fibroblasts also have other uses