Cytokine Profiles and Hepatic Injury in Occult Hepatitis C Versus Chronic Hepatitis C Virus Infection

Abstract

Occult hepatitis C virus (HCV) infection is a new entity that should be considered when diagnosing patients with abnormal liver functions of unknown origin. This work was carried out to evaluate T-helper liT-helper 2 (Thl/Th2) cytokine profiles in patients with occult HCV infection versus chronic hepatitis C (CHC) infection, also to investigate any association between theses cytokines and liver histological features in both groups. Serum levels of Thl cytokines (IL-2, IFN-y) and Th2 (IL-4 and IL-IO) were measured in 35 patients with occult HCV infection compared to 50 patients with chronic hepatitis C infection and 30 healthy controls. We have found that Thl cytokines were significantly increased in patients with CHC infection than in both occult HCV infection and control groups (p<O.OOl). On the other hand, serum IL-4levels were higher in occult HCV infection than in CHC and control groups (p<O.OOl). Furthermore, serum IL-IO levels were higher in both patient groups vs control group (p<O.OOl), with no significant difference between CHC and occult HCV groups. Finally, only serum IL-IO levels were significantly higher among patients with high activity (A2-A3) than those with low activity (AO-Al) in both CHC and occult HCV groups (p=0.038, p=0.025, respectively). Patients with occult HCV infection exhibited a distinct immunoregulatory cytokine pattern that is shifted towards the Th2 arm.Chronic HCV infection is endemic in Egypt, and based on the results of Ray et al., approximately 91% of Egyptian patients with chronic HCV are infected with HCY genotype 4 (l). Occult HCY infection is characterized by the presence ofHCY RNA strand in liver biopsy and peripheral blood mononuclear cell specimens in the absence of detectable level ofHCY RNA in plasma by current laboratory methods, and in the absence or presence of anti HCY antibodies. This occult infection has been reported in individuals with chronic liver disease with unknown etiology (2). Patients with occult HCY infection present a milder disease than patients with chronic hepatitis C. The low number of infected hepatocytes found in patients with occult HCY infection may be related to less liver damage. Furthermore, immune response of these patients may be finely-tuned better than that of patients with chronic hepatitis C, leading to a more effective control of the infection (3). There is suggestive evidence that T-cell immunoregulatory cytokines may play a key role in influencing the persistence of HCY infection and the extent of liver

A New Twist to a Chronic HCV Infection: Occult Hepatitis C

“…The cytokine balance between Th1/Th2 may also be a factor in the development of OCI cases [ 77 , 84 – 89 ]. Mousa et al [ 87 ] investigated the role of cytokine profiles including cytokines related to T-cell immunoregulation in the development of OCI. They compared the cytokines responses between OCI and those with an identifiable chronic hepatitis C infection (CHC).…”

Occult HCV Infection: The Current State of Knowledge

“…Similar results were described by Mousa et al, who revealed that Th1-type cytokines were significantly increased in patients with CHC relative to OCI but that the serum IL-4 levels as a Th2-type cytokine were higher in OCI. The serum IL-10 levels were high in both groups, with no significant difference between CHC and occult HCV groups ( 71 ). In light of these studies, we believe that perturbation of the immune response balance toward Th2-type cytokines plays a role in the clinical scenario of OCI, causing the virus to persist with fewer manifestations than CHC.…”

Occult Hepatitis C Infection and its Clinical Relevance in Lymphoproliferative Disorders

“…On the other hand, individuals with an OCI had higher serum IL-4 levels than in CHC and the healthy controls. Serum levels of IL-10 were higher in both OCI and CHC groups compared with control (Mousa et al, 2014).…”

“…The cytokine balance between Th1/Th2 may be an important factor in the development of OCI cases (Gad et al, 2012;Mousa et al, 2014).…”