11. The pigment cell people always knew about John. 12. A maternal uncle has vitiligo, an autoimmune condition that destroys patches of pigment cells in the skin. 13. Phototaxis there is mediated by simple eyespots that consists of a pigment cell and a photoreceptor cell. 14. At this time, hogs cannot be successfully freeze branded, as their hair pigment cells are better protected. 15. The varied and often vivid colours of echinoderms are produced by the action of skin pigment cells . 16. Melanoma occurs when the skin's pigment cells become cancerous, most often after prolonged exposure to the sun. 17. The signal by which sunlight stimulates melanin to pour out of pigment cells is unknown, Dr . Gilchrest said. 18. Mutations on KIT appear to limit the migration of melanocytes, leaving the extremities and midline devoid of pigment cells . 19. John is cited extensively in both the pigment cell literature and the literature on the toxicity of anticancer drugs. 20. Skin color changes as the larvae develop and pigment cells migrate and concentrate in different regions of the body.
