Abstract
Central centrifugal cicatricial alopecia (CCCA) is a type of primary scarring alopecia. Whether scaring alopecia occurs due to environmental, genetic, infectious, or autoimmune factors, or is multifactorial remains unclear. A comprehensive retrospective search of our pathology database was conducted to identify patients with CCCA and further characterize this scarring alopecia. Four specimens from African-American patients (2 females and 2 males) were identified. Skin sections from normal patients were used as controls. A two-sample t-test was used to analyze normal vs. abnormal groups. Light microscopy revealed histopathologic features consistent with CCCA. All 4 biopsy specimens showed a preponderance of CD3+ T cell population in the perifollicular region when compared to the intrafollicular region. Also, a parafollicular preponderance of CD4+ T cells, with a 1.2-4.5:1 CD4/CD8 ratio was noted. Intrafollicular findings showed more mixed results, which included a sparse CD3+ T cell infiltrate, a CD3+ T cell infiltrate with a CD4:CD8 ratio of 1.6:1, and primarily CD4+ T cells. All four biopsy specimens were negative for PD-L1 and caspase-3 had increased immunoreactivity. The two-sample t-test showed a dyskeratosis count/index with a p-value of 0.03816 and caspase 3 positive cell count/index with a p-value of 0.0466. In our study, 4 of the 4 cases also showed a predominance of CD4+ T cells in the perifollicular region. The cases were uniform regarding PDL1 and caspase-3, displaying an absent expression of the former and increased immunoreactivity of the latter, which raises the question of the role PDL1 and caspase in CCCA. Although PADI3 abnormalities have been associated with features of CCCA, it does not entirely explain the immune privilege collapse. Our findings support the idea of CCCA being mainly a CD4+ T cell lymphocytic-associated scarring alopecia and raise questions about the role of caspase 3 in hair follicle cell death in CCCA.
Financial Disclosure:
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