Table 1. Effects of Schistosome Coinfection on the Host Immune Response to Hepatitis C Virus.
| Study | Study Type | Sample Size | Sex (% Female) | Age in Years (Weighted Mean) | Country | Species | Immune and Viral Alterations in Schistosome Coinfected | Overall Effects of Schistosomes on HCV Infection |
|---|---|---|---|---|---|---|---|---|
| Kamal 2001 [20] | Human | 32 | 34% F | 28.0 | Egypt | S. mansoni |
↑ IL-4 ↑ IL-10 ↓ CD4+ |
Some studies report impaired anti-HCV responses of CD4+ helper T cells Decreased Th1 immune response (IFN-ɣ) and increased Th2 immune response (IL-4, IL-10) Increased HCV viral load and replication Impaired response and increased relapse after interferon therapy |
| Kamal 2001 [21] | Human | 85 | 35% F | 38.0 | Egypt | S. mansoni | ↓ CD4+ | |
| Kamel 2014 [22] | Human | 82 | 43% F | 51.2 | Egypt | S. mansoni | No difference in CD4+ or CD8+ | |
| Loffredo-Verde 2015 [23] | Human | 44 | 41% F | 39.5 | Egypt | S. mansoni |
No difference in CD4+
or CD8+ ↑ granzyme B+ T regulatory cells ↑ HCV viral load |
|
| Elrefaei 2003 [24] | Human | 24 | Not reported | 41.0 | Egypt | S. mansoni | ↓ Memory T-cells | |
| Kamal 2004 [25] | Human | 68 | 40% F | 34.3 | Egypt | S. mansoni |
↓ CD4+
Th1 intrahepatic T cells ↑ HCV viral load |
|
| El-Kady 2005 [26] | Human | 70 | 30% F | 44.3 | Egypt | S. mansoni |
↑ IL-4 ↑ IL-10 ↓ IFN-ɣ |
|
| Emam 2006 [27] | Human | 50 | 44% F | 44.7 | Egypt | S. mansoni |
↑ IL-4 ↑ IL-10 ↓ IFN-ɣ |
|
| Ahmed 2016 [28] | Human | 107 | 47% F | Range, 30–81 years | Egypt | S. mansoni |
↑ HCV viral load ↑ IL-28B No difference in IFN-ɣ |
|
| Elrefaei 2004 [29] | Human | 38 | Not reported | 42.5 | Egypt | S. mansoni |
No difference in IL-10 or IFN-ɣ with HCV peptide stim; ↑ IL-10 and ↓ IFN-ɣ with PHA stim* |
|
| Bahgat 2010 [30] | In vitro | Not reported | Not reported | Not reported | Egypt | S. mansoni | ↑ HCV viral replication | |
| El-Awady 2006 [31] | In vitro | 26 | Not reported | Not reported | Egypt | S. mansoni | ↑ HCV viral replication | |
| Edwards 2005 [32] | Animal | Not reported | Not reported | Not reported | Not reported | S. mansoni | ↑ HCV viral replication | |
| El-Shazly 1994 [33] | Human | 60 | 17% | 41.0 | Egypt | S. mansoni |
After interferon therapy: ↓ % ALT** normalization ↓ Response rate ↑ Relapse rate |
|
| Kamal 2000 [34] | Human | 62 | 35% | 43.1 | Egypt | S. mansoni |
After interferon therapy: ↓ Response rate ↑ Relapse rate |
*Phytohemagglutinin (PHA) stimulation, a positive control
**Alanine aminotransferase