Persistence of Hepatitis C Virus during and after Otherwise Clinically Successful Treatment of Chronic Hepatitis C with Standard Pegylated Interferon α-2b and Ribavirin Therapy

Abstract

Resolution of chronic hepatitis C is considered when serum HCV RNA becomes repeatedly undetectable and liver enzymes normalize. However, long-term persistence of HCV following therapy with pegylated interferon-α/ribavirin (PegIFN/R) was reported when more sensitive assays and testing of serial plasma, lymphoid cells (PBMC) and/or liver biopsies was applied. Our aim was to reassess plasma and PBMCs collected during and after standard PegIFN/R therapy from individuals who became HCV RNA nonreactive by clinical testing. Of particular interest was to determine if HCV genome and its replication remain detectable during ongoing treatment with PegIFN/R when evaluated by more sensitive detection approaches. Plasma acquired before (n = 11), during (n = 25) and up to 12–88 weeks post-treatment (n = 20) from 9 patients and PBMC (n = 23) from 3 of them were reanalyzed for HCV RNA with sensitivity <2 IU/mL. Clone sequencing of the HCV 5′-untranslated region from plasma and PBMCs was done in 2 patients. HCV RNA was detected in 17/25 (68%) plasma and 8/10 (80%) PBMC samples collected from 8 of 9 patients during therapy, although only 5.4% plasma samples were positive by clinical assays. Among post-treatment HCV RNA-negative plasma samples, 9 of 20 (45.3%) were HCV reactive for up to 59 weeks post-treatment. Molecularly evident replication was found in 6/12 (50%) among PBMC reactive for virus RNA positive strand collected during or after treatment. Pre-treatment point mutations persisted in plasma and/or PBMC throughout therapy and follow-up. Therefore, HCV is not completely cleared during ongoing administration of PegIFN/R otherwise capable of ceasing progression of CHC and virus commonly persists at levels not detectable by the current clinical testing. The findings suggest the need for continued evaluation even after patients achieve undetectable HCV RNA post-treatment.

Assessment of Hepatitis C Virus RNA in Peripheral Blood Mononuclear Cells as a Predictor of Response to Pegylated-Interferon and Ribavirin: A Cohort Study

“…In contrast to the current study, Chen et al (19) and Taliani et al (20) found that detection of HCV RNA in PBMCs specimens could not predict relapse after treatment. One of the weak points of Chen's study was the small number of patients with detectable HCV RNA in their PBMCs (19).…”

“…Sample size was one of the advantages of the current study compared to previous studies (14,(19)(20)(21)(22) type 3a at the end of treatment (14). Intervals of the follow up of patients in a study by Coppola (21) were the same as the current study.…”

“…One of the weak points of Chen's study was the small number of patients with detectable HCV RNA in their PBMCs (19). Another possible reason could be the use of conventional IFN instead of PegIFN, which was used in this study.…”

Authentic Patient-Derived Hepatitis C Virus Infects and Productively Replicates in Primary CD4 + and CD8 + T Lymphocytes In Vitro

“…The combined results from qRT-PCR and nRT-PCR/NAH analyses showed that virus was detected in 10 out of 13 CHC patients (76.9%) whose PBMC were available for analysis (Table 1). It is of note that PBMC were examined without prior ex vivo mitogen stimulation that normally augments HCV RNA expression and virus replication in PBMC of patients with low HCV loads in these cells (4,9,10,15,29,30,42).…”

“…In addition to symptomatic chronic infection, which is normally accompanied by circulating HCV RNA and anti-HCV antibodies, HCV also persists as an essentially clinically silent (occult) infection accompanied by very low levels of HCV RNA in serum (usually below 100 to 200 virus genome copies or virus genome equivalents [vge]/ml), liver, and peripheral blood mononuclear cells (PBMC) (3). This occult HCV infection (OCI) may continue for decades after spontaneous (self-limited) or antiviral therapy-induced resolution of hepatitis C (4)(5)(6)(7)(8)(9)(10)(11). In this context, the accumulated experimental data indicate that HCV propagates not only in the liver but also in the immune system, where it can modify the proliferation and function of affected cells (12)(13)(14)(15)(16)(17)(18).…”