Mhammet Cemil SAVAŞ, İrfan KORUK, Mehmet KORUK, Abdurrahman KADAYIFÇI, İbrahim SARI

Association of prion protein with the stage of liver fibrosis in chronic viral hepatitis

Amaç: Prion protein (PrP) ekspresyonu karaciğer fibrozisinde anahtar rol oynayan karaciğer yıldızsı hücrelerinde gösterilmiştir. Bu çalışmada PrP ekspresyonu ile kronik viral hepatit hastalarındaki hepatik inflamasyon ve fibrosis arasındaki ilişki araştırılmıştır. Gereç ve Yöntemler: 40 kronik viral hepatit hastasının karaciğer biyopsileri ve kontrol grubu olarak da 10 adet metastatik karaciğer hastalığı nedeniyle opere olan ve normal karaciğer dokusu bulunan hastaların biyopsileri çalışmaya alındı. İmmün boyama sonrası PrP boyanma indeksi her mikroskopik alandaki PrP pozitif hücreler sayılarak hesaplandı. Hepatik inflamatuvar aktivite ve fibrozis skorları ile PrP pozitif hücre sayısı arasındaki ilişki karşılaştırldı. Bulgular: Kronik viral hepatit hastalarının karaciğerlerinde değişik oranlarda PrP ekspresyonu saptanırken, kontrol grupta hiç boyanma gözlenmedi. Ayrıca PrP boyanma indeksi ile kronik hepatit inflamatuvar aktivite derecesi ve fibrozis evresi arasında anlamlı bir korelasyon bulundu (inflamasyon için p=0.0001, fibrozis için p=0.005). Sonuç: PrP aktivitesi karaciğer yıldızsı hücrelerinin bir belirleyicisidir. Ayrıca PrP boyanmasının kronik viral hepatit hastalarında karaciğer inflamasyonu ve fibrozisi ile iyi bir korelasyonu mevcuttur.

Kronik viral hepatitde prion protein ve karaciğer fibrozis evresi arasındaki ilişki

Objective: Prion protein (PrP) expresion has previously been demonstrated in activated hepatic stellate cells (HSC), which play a key role in the development of liver fibrosis. In this study, we aimed to investigate the correlation between PrP expression and hepatic inflammation/fibrosis in patients with chronic viral hepatitis (CVH). Material and Methods: Liver specimens of 40 patients with CVH and 10 patients with metastatic liver disease having a normal liver architecture as a control group were evaluated. ThePrP staining index was calculated by counting PrP positive cells per microscopic field after immunostaining. Hepatic inflammatory activity and fibrosis scores were evaluated and compared with the number of PrP positive HSC. Results: Varying degrees of PrP expression were detected in histologic samples of the liver in patients with CVH, whereas no staining was observed in control specimens. It was also detected that the grade of inflammatory activity and stage of liver fibrosis were significantly correlated with PrP staining index (p=0.0001 for inflammation and p=0.005 for fibrosis). Conclusions: PrP is a good marker of activated HSC and correlates well with the inflammatory activity and stage of fibrosis in CVH.

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