Volume: 2 Issue: 4
Year: 2025, Page: 156-162, Doi: https://doi.org/10.71325/ajjms.v2i4.25.90
Received: Nov. 13, 2025 Accepted: Nov. 30, 2025 Published: Dec. 29, 2025
Background: The infection instigated by the Hepatitis C virus (HCV) continues to pose a substantial challenge to global health, with the advancement of the disease being profoundly affected by the immune responses of the host organism. Programmed cell death protein-1 (PD-1) and Interleukin-25 (IL-25) are pivotal immunoregulatory entities that have been associated with the phenomena of viral persistence and immune exhaustion. Aim: This investigation sought to elucidate the complex interplay among PD-1, IL-25, and viral load in subjects afflicted with HCV. Patients and Methods: A total of 110 subjects were enlisted for the purpose of this investigation, encompassing 40 individuals diagnosed with HCV exhibiting viremia, 40 subjects devoid of viremia, and 30 healthy control participants. Demographic attributes were evaluated, while serum concentrations of PD-1 and IL-25 were measured through the application of enzyme-linked immunosorbent assay (ELISA); furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to ascertain the HCV viral load. Results: The median serum level of PD-1 in HCV patients with viremia 3.73 ng/ml (range= 1.06-8.43 ng/ml pg/ml) which was higher than non-viremic patients (median= 2.33 ng/ml, range= 1.04-8.32 ng/ml) or controls (median= 2.41 ng/ml, range= 1.04- 3.98 ng/ml), with significant differences. In contrast, non-viremic HCV patients exhibited a markedly elevated mean serum concentration of IL-25 (33.35± 6.59 pg/ml) in comparison to both viremic HCV patients (15.19±3.77 pg/ml) and control subjects (13.64± 4.31 pg/ml), with statistically significant differences observed. Furthermore, PD-1 demonstrated a significant positive correlation with viral load (r= 0.375, p=0.040), as well as a significant negative correlation with IL-25 (r= -0.221, p= 0.043). Conclusion: The findings emphasize a multifaceted interplay between PD-1, IL-25, and the viral load of HCV. The augmented expression of PD-1 may promote viral persistence through mechanisms of immune suppression, whereas IL-25 may contribute to the attenuation of disease progression. These immunological indicators could serve as promising therapeutic targets for the modulation of immune responses in the setting of chronic HCV infection.
Keywords: Hepatitis C Virus; Programmed Cell Death-1; Interleukin-25; Viral Load
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© 2025 Published by Laxmi Memorial Education Trust. This is an open-access article under CC BY 4.0 license. (https://creativecommons.org/licenses/by/4.0/)
Gaidan AM. The Interplay of Programmed Cell Death Protein-1 (PD-1), Interleukin-25 (IL-25) and Viral Load in Patients with Hepatitis C. AJ J Med Sci 2025;2(4):156-162