Henoch-Schönlein Purpura Hastalarının Böbrek ve Cilt Dokularında Yardımcı T Hücre Yanıtının Analizi

Abstract

Henoch-Schönlein purpura (HSP) or IgA vasculitis is the most common childhood vasculitis in our country. The cardinal feature of the disease is a purpuric rash predominantly on lower extremities. Joint, gastrointestinal tract and renal involvement may also be observed. During the course of the disease, renal involvement may be observed in 30-60% of patients. In recent years, the role T cells in pathogenesis of HSP/IgA vasculitis has become a focus for research. In this study, the role of cytokines and transcription factors (FOXP3) of T helper cells in disease pathogenesis and their relations with clinical and histopathological parameters were investigated. Twentytwo patients diagnosed as HSP/IgA vasculitis with renal biopsy and non-tumoral renal tissues of nephrectomy materials of 20 patients diagnosed as Wilms tumor (control group) were included in the study. Immunohistochemical IFN-gamma, IL-4, IL-17 and FOXP3 expressions were investigated. Dispersion and intensity scores of immunohistochemical stainings were evaluated in the glomerular and tubulointerstitial areas. Renal biopsy specimens of HSP/IgA vasculitis patients had higher IFN-gamma, IL-4, IL-17 glomeruler and tubular scores when compared to the control group which was statistically significant. Interferon-gamma glomerule and tubule scores were positively correlated with protein/creatinine ratio of early morning urine specimen at the time of kidney biopsy. Interleukin-17 glomerule scores correlated negatively with serum albumin levels and positively with qualitative proteinuria at the time of kidney biopsy. Furthermore, IL-17 glomerular scores were positively correlated with the percentage of crescents. There was no difference of the amount of glomerular and tubuler FOXP3+ cells between HSP/IgA vasculitis and the control groups. Henoch-Schönlein purpura/IgA vasculitis group had more FOXP3+ cells on interstitial area when compared to the control group. There was no correlation of FOXP3 expression with any clinical parameter. Skin biopsies of patients with preliminary diagnosis of HSP and non-pathological skin biopsies of the control group were the second part of the study. In the specimens vii obtained from the area with a lesion, IFN-gamma, IL-4 and IL-17 expressions were statistically higher when compared to normal skin which was statistically significant. FOXP3 expressions were not statistically different. Our results showed that all T helper subtypes play role in pathogenesis of HSP/IgA vasculitis. Relations of Th17 cells with proteinuria and crescent indicates its role in renal prognosis of the patients. Better understanding of the role of these cells and processes may bring forward their potentials of being therapeutic targets.