Table 3.
Comparison of nonviremic EIA-positive injection drug users with or without in vitro neutralizing antibodies (nAbs).
| Characteristic | Nonviremic EIA-positive IDUs | Pa | |
|---|---|---|---|
| With nAbs (n = 9) | Without nAbs (n = 7) | ||
| Age, median (IQR), years | 53 (51.0–54.5) | 50 (45.0–51.0) | .0115 |
| Duration of IDU, median (IQR), years | 32 (31.5–37.0) | 30 (24.0–34.0) | NS |
| Frequency of IDU, median (IQR) | |||
| In the past month | 1 (0–65) | 1 (0–87.5)b | NS |
| In the past 6 months | 355 (54–391)c | 150 (12.5–830) | NS |
| No. of sex partners, median (IQR) | 1 (0–65) | 1 (0–4.5) | NS |
| HCV Abs, median (IQR), ECi score | 30.5 (28.5–30.8)c | 15 (3.6–29.8) | .0093 |
| HCV-specific T cell proliferation | |||
| No. (%) of subjects | 8 (89) | 4 (57) | NS |
| Response strength, median (IQR), SI | 13.4 (9.5–30.2) | 11.8 (5.1–72.2) | NS |
| HCV-specific T cell IFN-γ production | |||
| Subjects with T cell IFN-γ production, no. (%) | 6 (67) | 6 (86) | NS |
| Response strength, median (IQR), ELISPOTS/300,000 PBMCs | 65 (918.5–130.5) | 68 (29.5–111.5) | NS |
NOTE. Abs, antibodies; ECi, Vitros Immunodiagnostic Anti-HCV Assay (Ortho-Clinical Diagnostics); ELISPOT, enzyme-linked immunospots; HCV, hepatitis C virus; IDU, injection drug use; IFN, interferon; IQR, interquartile range; NS, not significant; PBMCs, peripheral blood mononuclear cells; SI, stimulation index.
a
By Mann-Whitney U test. One subject was not tested for neutralizing antibodies.
b
Data are shown for 6 subjects; 1 subject was not tested.
c
Data are shown for 8 subjects; 1 subject was not tested.