ABSTRACT
Hepatitis C virus (HCV) infection causes life threatening disease due to its persistence in the liver, over time leading to
cirrhosis and hepatocellular carcinoma. Therapeutic intervention with interferon (INF) - alpha combined with ribavirin
is aimed at viral clearance, Interferon and ribavirin might discontinue the virus induced hepatocytes damage, thus
slowing down the progress to end- stage liver disease. It has been demonstrated that HCV virion, via major structure
envelop (E) protein 2 or EIE2 complex could specifically bind to human CD81 molecule, thereby altering the cellular
activities in B cells, T cells and natural killer (NK) cells. CD81, a surface protein belonging to the tetraspanin family,
facilitates B–T cell interaction in the process of antigen presentation Evidence has revealed that CD81 on B and T cells
substantially enhanced T helper IL-4 secretion and NK-cell CD81 enabled E2-mediated reduction of the IFN-gamma
levels Those data suggest that CD81 might activate the pathway leading to a predominant type-2 immune response, and
as such be prone to cause a strong antibody production but weak or insufficient cytotoxic activities to clear the.The aim
of this work was to investigate the clinical relevance and the possible mechanism of CD81 down-regulation under IFN
alpha treatment to detect possible role of CD 81in response to INF therapy of chronic HCV patients.
Subjects and Methods: The study included: Group I: 10 healthy subjects. And 60 HCV patients classified into 3
groups: Group II: 20 chronic HCV patients have not received treatment Group IIIa: 20 chronic HCV patients have
received treatment responsive to treatment Group IIIb: 20 chronic HCV patients have received treatment not
responsive to treatment .the patients were subjected to: (CBC) .liver and kidney function tests and special investigation
CD 81, CD19, CD 22.
Results: TLC and PLT higher in group I while ALT and AST were significantly higher in group II, while T. bilirubin
was significantly higher in group IIIb, Direct bilirubin was significantly higher in group II ,and Alb was significantly
higher in group I ,ASMA and ANA more higher in group IIIb, AFP and TSH were significantly higher in group IIIb ,
there was negative correlation between CD81 and TLC positive correlation between ALT, AST and CD81 were
positively correlated to T Bilirubin , D Bilirubin and CD81.There was also significant negative correlation between
Albumin and CD81. CD81, CD19, CD22 and Lymphocytes were significantly higher in group IIIb.
Conclusion: In conclusion, CD81 down-regulation is a primary host response to interferon-alpha-based therapy and an
immunophenotype associated with anti-HCV sustained virological response (SVR)