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Alopecia areata, autoimmune, gene expression, hair follicles, RT-qPCR, toll like receptors, SALT-score
Background Alopecia areata (AA) is a hair loss of scalp with out scarring and other hair bearing area. In AA immune system invade hair follicles The innate immunity and Toll-like receptors (TLRs) can express significant role in this autoimmune disorder. According to available data the role of expression of TLRs studied in multiple cutaneous disorders; however, some were investigated in relation to pathogenesis of AA
Methodology This retrospective cross-sectional study is to investigate the role of TLR-3, TLR-7, TLR-8, and TLR-9 in the AA patients. 40 (AA) patients were recruited from the Institute of Skin Disease Sindh and 10 healthy controls after getting an informed consent. Venous whole blood was used to extract the total RNA, and by using a real time quantitative PCR (RT-qPCR) expression of four TLRs with GAPDH (a house-keeping gene) was determined. The ANOVA statistical test was applied to analyze the expression values.
Results The expressions of all the four TLRs in AA were considerably significant than in the controls. The average relative expression of TLR-3, TLR-7, TLR-8, and TLR-9 was 54.40, 111.69, 34.45, and 112.51 respectively in all the AA patients. By comparing between male and female AA patients, the expression of all the four TLRs was non-significantly higher in male AA patients (p<0.5). TLRs expression was observed highest in the age group 21-30 yrs.
Conclusion This study identifies the significance of TLRs expression in AA patients indicating the fundamental role in autoimmunity, which will further provide a new insight in the therapeutic strategies of AA and other linked cutaneous diseases. Furthermore, studies are required to understand the targeted TLRs expression in introducing new modulated therapies for management of AA patients.
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