Detailed information about anatomy of human hair

Cell Isolation & Culture

Hair loss, which affects people so negatively, is a common problem so far as psychological impact is concerned. The causes can be hormone sensitivity, autoimmunity, radiation therapy, chemotherapy, and potentially many other factors. The desire to look good makes people affected by hair loss look for treatment.

Treatment may range from clinically proven pharmaceutical treatments such as topical minoxidil solution and oral finasteride to surgical options for autologous hair transplantation, and transplantation after hair cloning. Hair follicles are removed from a nonbalding region of the scalp and transplanted to the balding region.

But none of these treatments are perfect. Medications work with limited effect and last only for the time the patient uses the drug. When someone stops using the drug, the hair loss often returns. Surgical therapies, on the other hand, can provide permanent relief from hair loss. However, they not only require intense effort to develop improvements but can leave a lot to be desired so far as results are concerned.

Now scientists are working on a perfect solution to balding woes, the follicular cell implantation (FCI) technique. As the term suggests, follicular cells are developed in culture and then implanted inside the scalp skin. These cells then promote new hair follicles to grow. These cultures can also be used in hair cloning and for repairing hair follicle damage.

The permanency and non-dependency on the quantity of donor hair makes this treatment the perfect approach to treating hair loss. To start with, the patient’s own cells are used, taken from just a few hair follicles. These cells can then be grown to make enough cells to potentially promote new hair follicles even in extensively bald individuals. This process involves cell isolation and then cell culture.

Isolation and culture of follicular cells

Follicular cell implantation involves removing dermal papilla (DP) cells or dermal sheath cup (DSC) cells from hair follicles existing at the non balding site at the back of the scalp, culturing them to make many more cells, and implanting them into skin where they will instruct the skin to form new hair follicles.

Sounds easy, but conventional culture of DP cells makes them lose their ability to induce new hair formation. Therefore a hair transplantation process using DP cell transplantation is not commercially viable without a good culture method which allows expansion of cell number without loss of inductive ability.

To counter this problem scientists have proposed two methods that are able to support expansion of cell number while also maintaining the hair inductive potential of DP cells. They are:
  • In the first method, researchers used conditioned medium (CM) collected from mammalian epidermal cells (keratinocytes), or co-culture with keratinocytes. Cells developed this way have been shown to support both expansion of DP and DSC cell number and maintenance of the hair inductive phenotype over several culture passages. However, this method would require maintenance of a bank of cells with identical properties that can be used in the DP and DSC cell culture. This approach, with all its safety testing and eventual cell depletion problem, will jack up the costs considerably, besides there can be variations between the donors of the original cell strains that may result in irreproducible manufacturing conditions between different patients.
  • In the second method, dermal papilla cells are made to go through culture in the presence of an increased level of WNT protein or an agent that mimics the effects of WNT-promoted signal transduction. This method is based upon the discovery that WNT signaling is active during hair morphogenesis. The WNT pathway is active in the epidermal placode during development, and WNT proteins are thought to be part of the signal that triggers the dermal condensate to form.

    However, in this method, additional safety tests are required because the cells are producing or responding to recombinant proteins. However, WNT gene expression in the producer cells is quite stable. This would cause the re-deriving or sub-cloning the cells in the event WNT gene expression is lost or reduced over time in culture.