IL-17 A expression negatively correlates with ?? T-Cell density in human psoriasis lesions: a novel implication for disease pathogenesis

Abstract

BackgroundPsoriasis, an inflammatory autoimmune disease, arises from intricate interactions between the immune system and epithelium. Recent reports have suggested new roles for gamma delta (gamma delta) T-cells in addition to immune surveillance, however, it remains to be determined whether the mechanisms identified in psoriasis murine models have a similar role in humans. The aim of the present study was to investigate the relationship between IL-17 A mRNA expression levels and gamma delta T-cell frequency in human psoriatic lesions, and to clarify the potential role of gamma delta T-cells in psoriasis pathogenesis.MethodsThe study involved 20 patients diagnosed with psoriasis and 16 control subjects. Expression of the IL-17 A gene was measured in formalin-fixed paraffin-embedded (FFPE) tissues by RT-PCR method. TCR gamma delta+ immunofluorescence staining was performed to measure the distribution of gamma delta T-cells in the same samples.ResultsIn psoriatic lesion biopsies, TCR gamma delta+ T-cell percentage was found higher than the control samples. Additionally, psoriasis patients exhibited elevated levels of IL-17 A gene expression. In addition, this study showed a weak negative correlation between the proportion of gamma delta T-cells and IL-17 A mRNA expression in psoriatic skin samples.ConclusionA weak negative correlation between IL-17 A mRNA levels and gamma delta T-cell presence in human psoriasis lesions highlighting the novel effector functions of these cells in psoriasis pathogenesis.