Characterization of inflammatory infiltrates in male pattern alopecia: implications for pathogenesis

Abstract

Hair-bearing, transitional, and alopecic scalp from three males and one female with progressive pattern alopecia were examined. Ultrastructural studies disclosed measurable thickening of the follicular adventitial sheaths of transitional and alopecic zones compared with those in the non-alopecic zones. This finding was associated with mast cell degranulation and fibroblast activation within the fibrous sheaths. Immunohistochemically, control biopsies were devoid of follicular inflammation (n = 3), while transitional regions consistently showed the presence of activated T-cell infiltrates about the lower portions of follicular infundibula. These infiltrates were associated with the induction of class II antigens on the endothelial linings of venules within follicular adventitia and with apparent hyperplasia of follicular dendritic cells displaying the CD1 epitope. Inflammatory cells infiltrated the region of the follicular bulge, the putative source of stem cells in cycling follicles. The data suggest that progressive fibrosis of the perifollicular sheath occurs in lesions of pattern alopecia, and may begin with T-cell infiltration of follicular stem cell epithelium. Injury to follicular stem cell epithelium and/or thickening of adventitial sheaths may impair normal pilar cycling and result in hair loss.

Efficacy of a Nutritional Supplement, Standardized in Fatty Acids and Phytosterols, on Hair Loss and Hair Health in both Women and Men

“…It is commonly accepted that 5αRed activity is not the only pivotal point in hair pathology; indeed, follicular micro inflammation, oxidation and microcirculation at the hair bulb are the leading causes of these conditions [31][32][33]. Furthermore, the lack of immunity defense or nutritional deficiencies can increase the seriousness or enhance the disorders [34].…”

Controlled clinical trial for evaluation of hair growth with low dose cyclical nutrition therapy in men and women without the use of finasteride

“…Vitamin D has direct action on induction of hair growth from the dermal papilla. The role of oxidative stress [42] , nutrients, vitamins [43] , minerals [44,45] , amino acids in maintaining immunity, preventing micro inflammation [46,47] , and promoting hair growth has been discussed by several research scientists. The details of the role of non-androgenic factors have previously been published [48] .…”

Alopecia androgénica femenina: nuevos factores fisiopatológicos y futuras tendencias para un abordaje clínico más integral

“…Se ha confirmado la presencia de fenómenos de microinflamación en las zonas del cuero cabelludo con alopecia androgénica, con infiltración de linfocitos T activados y macrófagos en el tercio superior del folículo piloso, cerca del infundíbulo 23 . Esta localización superior del infiltrado inflamatorio sugiere que el problema causal podría afectar a esta región y permite distinguir esta forma de alopecia de la alopecia areata, en la que también se observa infiltrado inflamatorio, pero localizado en el bulbo y la papila del folículo pilosebáceo.…”