Mehmet BERKÖZ, Nurcan ARAS, Serap YALIN, KARAKAŞ Sevim ÇELİK, Özlem KANDEMİR, Ayşe KUBİLAY, Gülay BÖREKÇİ, İrem BEKALP

Kronik hepatit c hastalarında ıl 18 promotor bölge polimorfizmi

Amaç: Kronik HCV enfeksiyonu virüs ve immün sistemin etkileşimleri sonucu oluşan dinamik bir süreçtir. Hastalığın seyri bireyler arasında oldukça büyük ölçüde değişkenlik gösterir. Bu nedenle günümüzde HCV enfeksiyonunun altında yatan mekanizmaları araştıran çalışmalarda popülasyonlardaki genetik varyasyonları araştıran çalışmalar ön plana çıkmaktadır. Özellikle immün cevapta rol oynayan genlerdeki polimorfizmlerin HCV enfeksiyonuna genetik yatkınlıkla ilişkili olabileceği düşünülmektedir. IL18 Th1, immün cevapta önemli rolü olan proinflamatuar bir sitokindir. Promotor bölgesinde birçok farklı inflamatuar ve otoimmün hastalıkla ilişkili olduğu bilinen iki polimorfizmi (137G/C ve 607A/C) gösterilmiştir. Ancak IL18 gen polimorfizminin HCV enfeksiyonuna karşı konağın immün cevabını etkileyip etkilemediğini araştıran çok az sayıda çalışma vardır. Bu çalışmada kronik hepatit C enfeksiyonu ile IL18 promotor polimorfizmi arasında ilişki olup olmadığının araştırılması amaçlanmıştır. Yöntem: HCV enfeksiyonunda IL18 -607C/A (rs1946518) ve −137G/C (rs187238) polimorfizmlerinin etkisini araştırmak için PCR-RFLP yöntemi kullanılarak 65 kontrol ve 63 Hepatit C hastasında IL18 polimorfizmleri çalışılmıştır. Bulgular: Kronik hepatit C hastaları ile kontrol grubu arasında IL18 genotip ve allel frekansları açısından anlamlı bir farklılık bulunamadı. Sonuç: Bulgularımız IL18 polimorfizminin Kronik Hepatit C enfeksiyonunun gelişimine zemin hazırlayan önemli bir faktör olmadığını göstermiştir.

Promoter polymorphisms of ıl18 gene in chronic hepatitis c patients

Objective: Chronic HCV infection is a dynamic state of the interactions between virus and host immune response, and the natural course varies greatly among different individuals. So currently, most studies investigating the underlying mechanisms of HCV infection have focused on genetic variations in the human population. Specially, polymorphisms of immune response genes may be considered related to a genetic susceptibility to HCV infection. IL18 is a proinflammatory cytokine that plays an important role in the Th1 response. IL18 gene has two polymorphisms ( 137 G/C and 607 A/C) within the promoter of the gene have been associated with different inflammatory and autoimmune diseases. However, there are a few study whether IL18 polymorphisms have influence on host immune response to HCV infection. The aim of the present study was to determine whether IL18 promoter polymorphisms association with chronic HCV infection in Turkish subjects. Method: To evaluate the role of host IL18 -607C/A (rs1946518) and −137G/C (rs187238) polymorphism in predicting HCV infection, IL18 gene polymorphisms were studied in 63 hepatitis C patients and 65 control subjects by using the PCR-RFLP method. Results: No significant differences were observed in genotype or allele frequencies among chronically HCV-infected and healthy subjects. Conclusion: Our results suggest that the IL18 gene polymorphism is not a major factor predisposing to the development of chronic Hepatitis C infection.

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