The following description is provided to assist the understanding of the reader. None of the information provided or references cited is admitted to be prior art.
Vitiligo is a pigmentation disorder in which melanocytes, the cells responsible for skin pigmentation, are destroyed. As a result, white patches appear on the skin in different parts of the body. Although patches are initially small, they often enlarge and change shape. Vitiligo lesions can appear anywhere, but are most commonly found on the acral areas, mucous membranes (tissues that line the inside of the mouth and nose), retina and genitals. Other symptoms include increased photosensitivity, decreased contact sensitivity response to dinitrochlorobenzene, and premature whitening or graying of hair that grows on areas affected by vitiligo. A Black light can be used in the early phase of this disease for identification and to determine effectiveness of treatment. Skin with vitiligo, when exposed to a Black light, will glow yellow, green or blue, in contrast to healthy skin which will have no reaction.
A number of medical therapies including topical steroid therapy, psoralen photochemotherapy, and depigmentation can reduce the appearance of vitiligo. However, each of these therapies is associated with drawbacks in efficacy and/or severe side effects such as skin shrinkage, severe sunburn, blistering, hyperpigmentation, cataracts, inflammation, nausea, vomiting, itching, abnormal hair growth, and skin cancer. Furthermore, surgical therapies are not optimal because they are only appropriate for a subset of vitiligo patients and are accompanied by the risk of infection, scarring, blistering, and abnormal pigmentation. Thus the need for therapeutic strategies that effectively and safely combat vitiligo still remains.