Pathomechanisms of Immune-Mediated Alopecia

April 2019 in “ International Immunology ”

Alessandra Anzai, Eddy Hsi Chun Wang, Eunice Lee, Valéria Aoki, Angela M. Christiano

alopecia areata primary cicatricial alopecia T cells hair follicles dendritic cells macrophages NK cells cytokines CD8+NKG2D+ T cells Janus kinase inhibitors gut microbiome scalp trauma skin care products AA PCA JAK inhibitors

Studysummary This review discusses the mechanisms behind alopecia areata and primary cicatricial alopecia and reports no new clinical results, aiming to guide the development of targeted treatments.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The 2019 study "Pathomechanisms of immune-mediated alopecia" investigated the mechanisms behind immune-mediated hair loss, specifically alopecia areata (AA) and primary cicatricial alopecia (PCA). The study found that AA is primarily driven by T cells, which attack hair follicles, causing hair loss. Other immune cells, such as dendritic cells, macrophages, and NK cells, also play a role in this process, as do cytokines, small proteins that aid in immune responses. The study also found that genetic and environmental factors contribute to AA and PCA, with certain genes and immune cells, particularly CD8+NKG2D+ T cells, playing a significant role in AA. The study also noted the effectiveness of Janus kinase inhibitors (JAKi) in treating AA. Changes in the gut microbiome were suggested as potential triggers for AA. For PCA, potential genetic components and external triggers, including scalp trauma and the use of certain skin care products, were identified. The study concluded that understanding these mechanisms is crucial for developing specific and effective treatments.

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Research cited in this study

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