US researchers have found a first potentially effective treatment against vitiligo, an autoimmune epidermis disease whose causes have not been clearly elucidated and against which no treatment has been discovered so far.
Vitiligo is characterized by a total depigmentation of the skin that leads to the formation of white, rather discrete plaques, mainly on the face, neck, hands, feet or joints. The absence of melamine, the pigment responsible for tanning, makes the skin in the affected areas no longer protected against ultraviolet light. To avoid the appearance of skin cancer, patients are advised to constantly avoid the sun, especially during the summer.
Worldwide, vitiligo, whose origin may be genetic (about 10 genes are involved) or generated by violent stress, affects an average of 5 people in a thousand, regardless of gender or skin color. Falsely accused by some British tabloids that he “bleached” his skin to get rid of the natural black color of his epidermis, American singer Michael Jackson had suffered from vitiligo. The only “positive” points of this disease: the disease is neither painful nor contagious.
Researchers at the Institute of Oncology affiliated with Loyola University in Chicago presented the spectacular effect of a genetically modified protein on mice touched by vitiligo.
Called HSP70i, this protein, made up of a chain of 641 amino acids, plays a key role in triggering the autoimmune response that destroys melanocytes (melanin producing cells) and triggers vitiligo.
American doctors, coordinated by Caroline Le Pool, injected mice suffering from this disease with a mutant form of the HSP70i protein to which they had previously changed their aminated acid.
The result was spectacular: the mutant protein replaced the normal protein and reversed the autoimmune reaction at the origin of vitiligo disease. The skin smeared with white spots of the mice became black again. “Mice seem normal”, said Caroline Le Pool. In addition, tests performed on human skin samples showed similar effects.
Of course, from mice to humans it is a fairly large step, but the authors of the study are already looking for funding for their project and an authorization to conduct clinical trials on human patients, while Loyola University has already filed papers to obtain a patent.
Nowadays, steroid-based creams and surgery have limited efficacy, generating significant side-effects and expensive, especially for grafts. Establishing long-term, effective and well-tolerated treatment would be a great relief for the sick. In France, a country where the disease is higher than the world average – between 1% and 2% of the population – about 1 million people suffer from vitiligo.