Volume 117, Issue 4, Pages 933-941 (October 1999) Recurrence of hepatitis C virus after loss of virus-specific CD4+ T-cell response in acute hepatitis C  J.Tilman Gerlach*,‡, Helmut M. Diepolder*,‡, Maria–Christina Jung*,‡, Norbert H. Gruener*, Winfried W. Schraut*, Reinhart Zachoval‡, Robert Hoffmann‡, C.Albrecht Schirren‡, Teresa Santantonio§, Gerd R. Pape*,‡  Gastroenterology  Volume 117, Issue 4, Pages 933-941 (October 1999) DOI: 10.1016/S0016-5085(99)70353-7 Copyright © 1999 American Gastroenterological Association Terms and Conditions

Fig. 1 Proliferative CD4+ T-cell response of the first sample in the acute phase of disease to recombinant HCV proteins (HCV-NS3, -NS4, -NS5, and -core) of PBMCs from 38 patients with acute hepatitis C. Patients are grouped according to the final outcome of disease in self-limited hepatitis C (SL, n = 20) and patients with chronic evolution (C, n = 18). Results are shown as SI = 3H-thymidine incorporation of antigen-stimulated PBMCs (cpm)/unstimulated control (cpm). Values ≥3 are considered significant. All patients with self-limited disease displayed a significant proliferative T-cell response against at least 1 of the viral proteins, while patients with chronic evolution mounted no or only transient antiviral T-cell responses. NS3 and NS4 revealed the most frequent (see Table 2) and most vigorous responses. In 4 patients, the proliferative response against NS5 was not tested in the first sample. Gastroenterology 1999 117, 933-941DOI: (10.1016/S0016-5085(99)70353-7) Copyright © 1999 American Gastroenterological Association Terms and Conditions

Fig. 2 (A) Proliferative response (3H-thymidine uptake) and (B) secretion of IFN-γ (ELISPOT assay) were assessed in patients with acute hepatitis C (n = 4) upon stimulation with HCV-specific antigen (C200) in CD4+- or CD8+-depleted PBMCs and in unfractionated PBMCs. Representative results of 1 patient. Depletion of CD4+ T cells but not depletion of CD8+ T cells resulted in a significant decrease of antigen-specific proliferation and IFN-γ secretion. Gastroenterology 1999 117, 933-941DOI: (10.1016/S0016-5085(99)70353-7) Copyright © 1999 American Gastroenterological Association Terms and Conditions

Fig. 3 Follow-up of HCV-RNA and ALT level (upper part of each graph), antiviral CD4+ proliferative T-cell responses (middle part of each graph), and number of spots representing IFN-γ–secreting cells/ 2 × 105 PBMCs in the ELISPOT assay (lower part of each graph) after stimulation with recombinant HCV protein (C200) in 2 representative patients with acute hepatitis C. (A) Patient with a self-limited course of acute hepatitis C and sustained vigorous proliferative T-cell responses against the viral proteins c33c (NS3), c100 (NS4), and c200 (NS3 and NS4). HCV RNA turns negative by week 8 and remains undetectable throughout the entire follow-up. Initially elevated ALT level falls to normal values in the acute phase. The increased number of IFN-γ–secreting cells upon antigen-specific stimulation is maintained during follow-up. (B) Patient with initially significant (SI ≥ 3) antiviral CD4+ T-cell responses and transient viral clearance. Loss of significant T-cell responsiveness is promptly followed by recurrence of HCV RNA. The precursor frequency of IFN-γ–secreting cells upon antigen-specific stimulation in the ELISPOT assay decreases during follow-up. Gastroenterology 1999 117, 933-941DOI: (10.1016/S0016-5085(99)70353-7) Copyright © 1999 American Gastroenterological Association Terms and Conditions

Fig. 4 Stimulatory index of HCV-specific T lymphocytes in the first ELISPOT assay within 6 months after onset of disease (SIE = number of spots after antigen-specific stimulation/number of spots in the control) for IFN-γ secretion after incubation of 2 × 105 PBMCs with viral protein (c200; 1 μg/mL) in healthy controls (n = 10), patients with acute hepatitis C and chronic evolution (n = 10), or patients with self-limited course of disease (n = 10). Differences are significant for healthy controls vs. self-limited course (**P = 0.020) and chronic evolution vs. self-limited course (*P = 0.025). Gastroenterology 1999 117, 933-941DOI: (10.1016/S0016-5085(99)70353-7) Copyright © 1999 American Gastroenterological Association Terms and Conditions