253 citations,
December 2007 in “Journal of Investigative Dermatology” The study explored how hair follicles (HFs) maintain immune privilege (IP) to avoid natural killer (NK) cell attacks, which typically target cells with low MHC class I expression. It was found that HFs actively suppress NK cells, with the HF epithelium expressing the NK cell inhibitor macrophage migration inhibitory factor. In healthy individuals, fewer NK function-activating receptors and more inhibitory receptors were present compared to those with alopecia areata (AA), an autoimmune disease linked to a breakdown of HF-IP. AA patients showed increased NK cell activity around hair follicles, suggesting a defect in NK cell inhibition that contributes to the disease's pathogenesis. This defect was previously unreported and highlighted the need for considering NK cell activity in AA management.
286 citations,
August 2007 in “Journal of Clinical Investigation” The study of alopecia areata provided insights into autoimmunity, particularly regarding immune privilege and the interaction between genetics and neuroimmunology. Alopecia areata was identified as a T cell–mediated autoimmune disease affecting hair follicles, with disease onset linked to the collapse of hair follicle immune privilege in humans and animal models. The research reviewed the involvement of HLA associations, other immunogenetic factors, and neuroendocrine parameters in the disease's pathogenesis, highlighting its significance as a model disease for the immunology community.
143 citations,
January 2007 in “The American Journal of Human Genetics” The study conducted a genomewide search for genetic linkage in 20 families with alopecia areata (AA), involving 102 affected and 118 unaffected individuals from the U.S. and Israel. It identified at least four susceptibility loci on chromosomes 6, 10, 16, and 18, with significant LOD scores on chromosomes 16 and 18. The findings supported previous associations of the human leukocyte antigen locus with AA and suggested that regions on chromosomes 16 and 18 might harbor genes involved in various skin and hair disorders. The study highlighted the complex genetic nature of AA, an autoimmune disorder affecting 1%-2% of the U.S. population, characterized by hair loss and psychological impact.
