The efficacy in treating vitiligo with a new cell therapy technique has been demonstrated according to results obtained in patients by a team of specialists at the Clínica Universitaria de Navarra. The procedure consists of transplanting the patient’s own epidermal cells (skin cells) from a pigmented area to specific unpigmented areas.
As Dr. Pedro Redondo (pictured right), a specialist in Dermatology at the medical center in Pamplona, explained, “We can objectively confirm that repigmentation is produced in the affected area with this technique and overall, the results are good.” So far the team at the medical center in Pamplona has treated ten patients with stable vitiligo by transplanting a monolayer of pigmented cells on amniotic membrane. “In all the patients we had high success rates, achieving repigmentation of 75 to 100% of the affected area,” the dermatologist added.
Amniotic Membrane Culture
The surgical treatment of vitiligo can be achieved in two different ways, either by using small skin grafts or cell cultures. "The novelty of this method is that we grow monolayers of pigmented cells on an amniotic membrane substrate," said Dr Redondo, director of the research study, Dr. Julio del Olmo, from the Dermatology Department, Dr Felipe Prósper and María García Guzmán (pictured center), director and laboratory technician respectively at the Clínica Universitaria Cell Therapy department, and Laura Guembe, from the University of Navarra's Applied Medical Research Centre (CIMA), also took part in the study.
The first step in applying this new technique to treat vitiligo is the culture of epidermal cells - a mixture of keratinocytes and melanocytes - followed by the preparation of selective cultures, growing the cells as a monolayer on an amniotic membrane matrix. “Until now,” indicated Dr. Prosper, “there has been no research on monolayer cultures of melanocytes because a suitable scaffolding medium had not been found.” Amniotic membrane culture has previously been carried out at the Clínica Universitaria de Navarra but it was applied in the development of other types of Cell Therapy treatments, principally ophthalmological treatments. “In short,” concluded the specialist, “this is a tissue engineering procedure.”
The Disease and Its Incidence
As we know, vitiligo is an autoimmune disease that is manifested as a skin condition and which affects in the region of 2% of the population. “The incidence of the disease is quite high. It consists of the appearance of white patches on the skin which, although causing no complications from the clinical point of view, is basically a significant aesthetic problem, especially in people with dark skin in whom the contrast in skin color is highlighted," explained Dr. Redondo.
So, while in Western countries it is only a cosmetic problem, in other geographical regions it can become a serious social problem, given that vitiligo is similar in appearance to the depigmentation which occurs in leprosy. “This is why in countries like India, where they have darker skin and where leprosy is still endemic, vitiligo can become a social stigma, as people are unable to distinguish the symptoms of the two diseases,” insisted the dermatologist.
Symptoms, Patients, and the Procedure
In general, the disease manifests at different times, ranging from periods when there is greater depigmentation to stages when affected areas may become spontaneously repigmented. In some patients the condition may also stabilize and medical treatments prove ineffective, but the disease does not progress either. In these stable patients what is known as surgical vitiligo treatment is applied.
The procedure developed by the team at the hospital center in Navarra commences by obtaining a biopsy (a small sample of the skin surface) from a part of the body which is pigmented, although normally hidden from view, such as the buttocks or the back. Then the skin sample is processed in the Cell Therapy area. There enzymes are used to separate the epidermis from the dermis in order to obtain the cells from the epidermis, which has now been broken up, which are required for culture purposes. Afterwards the cell units obtained are grown on amniotic membrane until they have multiplied to produce millions of cells.
The epidermal cells obtained as a result of the cell culture procedure must be processed until the cell surface grown is sufficient to cover the affected area. “Growth is exponential so, if the surface which needs to be treated is very extensive, the number of weeks the epidermal cells must remain in the culture medium will have to be increased,” the specialist added. In this way as many layers of cells as the affected area required are obtained.
The application of the amniotic membranes carrying the epidermal cells is performed in the operating theater. First of all, the white patches are treated using a CO2 laser. “The laser has to be applied very superficially in order to eliminate the external layer of the epidermis. The amniotic membranes carrying the epidermal cells are then implanted on the epidermis,” Dr. Redondo explained. Once they have been transplanted, the layers of melanocytes must be covered using an occlusive dressing, which will be removed in 3 or 4 days. Then the patient must be exposed to solar ultraviolet radiation, if it is an appropriate time of year, or UVA rays, following a specific protocol.
The surgical procedure is performed under local anaesthetic, which is necessary for the laser application. This is an outpatient procedure and the patient can go home afterwards.
Recommended for the Face
In general the specialists at the Clínica Universitaria de Navarra have applied this cell therapy technique to areas such as the face, a part of the body which is of most concern to patients, and where a more satisfactory response would be expected. According to these medical experts, there are parts of the body where repigmentation is not so successful, such as in the hands, where vitiligo is also commonly found.
“Moreover, it is better not to treat large areas but rather selective areas, which are stable and have not responded to conventional medical treatments,” emphasized the specialist. It is important to bear in mind that surgical treatment using layers of epidermal cells “must never be the first choice for vitiligo and it must never be applied in cases of active vitiligo,” concluded the dermatologist.
Illustration: From left to right, Dr. Enrique Andreu and the technician María García Guzmán, from the GMP laboratory of the Cell Therapy area at the Clínica of the University of Navarra, and Dr. Pedro Redondo, specialist at the department of Dermatology of the same healthcare center. -- Clínica of the University of Navarra.
Clínica of the University of Navarra Medical Services Departmental News (09/24/08)
Basque Research News (09/30/08)
No Abstract Available (Repigmentation of vitiligo by transplantation of autologous melanocyte cells cultured on amniotic membrane. British Journal of Dermatology, Volume 158 Issue 5, Pages 1168 – 1171)