The main targets for neutralizing anti-hepatitis C virus (HCV) antibodies (HCV-nAbs) are the E1 and E2
envelope glycoproteins. We have studied the characteristics of HCV-nAbs through a retrospective study
involving 29 HIV/HCV-coinfected patients who achieved sustained virological response (SVR) with pegIFNα+ribavirin anti-HCV therapy. Plasma samples at baseline and week 24 after SVR were used to
perform neutralization assays against fve JFH1-based HCV recombinant viruses coding for E1 and E2
from genotypes 1a (H77), 1b (J4), 2a (JFH1), 3a (S52) and 4a (ED43). At baseline, the majority of plasma
samples neutralized 1a, 1b, 2a, and 4a, but not 3a, genotypes. Twenty-four weeks following SVR, most
neutralizing titers declined substantially. Furthermore, titers against 3a and 2a were not detected in
many patients. Plasma samples with high HCV-nAb titers neutralized all genotypes, and the highest
titers at the starting point correlated with the highest titers at week 24 after SVR. In conclusion, high
titers of broad-spectrum HCV-nAbs were detected in HIV/HCV-coinfected individuals, however, those
titers declined soon after SVRThis study was supported by grants from Instituto de Salud Carlos III (ISCIII; grant
numbers PI14/01094 and PI17/00657 to JB, PI17/00903 to JGG, PI14CIII/00011 and PI17CIII/00003 to SR) and
Ministerio de Sanidad, Servicios Sociales e Igualdad (grant number EC11-241). Te study was also funded by the
RD16CIII/0002/0002, RD16/0025/0018, and RD16/0025/0017 projects as part of the Plan Nacional R+D+I
and co-funded by ISCIII- Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional
(FEDER
