Autoimmune vitiligo may help fight melanoma
Inducing vitiligo in persons with melanoma might enhance the natural immune response of these patients, according to data yielded by a recent study.
In the immunotherapy approach to cancer treatment, T cells attack tumors after recognizing antigens generated by the tumor cells. But noncancerous cells may produce molecules that are identical to those antigens, causing T cells to stage an unwanted autoimmune attack against the normal cells. This occurs in melanoma-associated vitiligo. In their quest to vanquish a skin cancer lesion, immune cells also destroy healthy melanocytes, leaving the person with a lack of normal skin pigmentation.
In exploring how vitiligo affected T cell responses to melanoma in mice, a team led by Mary Jo Turk, PhD, of Dartmouth Medical School in Lebanon, New Hampshire, learned that melanocyte destruction was required for tumor immunity. In addition, the T cells associated with vitiligo provided a lasting protection against tumor growth. These results indicate that autoimmune destruction of normal tissues is a beneficial process that occurs as the body fights cancer.
“This work establishes melanocyte destruction as a key determinant of lasting melanoma-reactive immune responses, thus illustrating that immune-mediated destruction of normal tissues can perpetuate adaptive immune responses to cancer,” wrote the researchers in a paper for The Journal of Clinical Investigation (www.jci.org/articles/view/44849/pdf).