Assessment of Haematological and Immunological Effect after New Direct ‎Acting Antiviral Drugs in Chronic Hepatitis C Virus Egyptian Patients

• Hepatitis C virus infection is one the most endemic infection all over the developing countries.
• With the introduction of new direct acting analogues in management of chronic hepatitis C virus infection, this lead to higher frequency of sustained virological response.
• Sofosbuvir and Dacltasvir are considered safe and tolerable agents with high efficacy in management of chronic hepatitis C virus infection
• Impact of direct acting analogues on immune cells proliferation is still a matter of controversy and frequent future studies are warranted.

Study patients: Are those patients with chronically infected with HCV infection and eligible for SOF-DAC regimen.

Table (1): Baseline and follow up complete blood picture the patients

Data expressed as mean (SD). RBCs: red cell cells; Hct: hematocrite; MCV: mean corpuscular volume; MCH: mean corpuscular hemoglobin; MCHC: mean corpuscular hemoglobin; RDW: red cell distribution width; MPV: mean platelets volume. *indicates to significant difference in comparison to baseline where comparison was done by paired t test between baseline data and different times of assessment.  

Table (2): Baseline and 3-months post-therapy other laboratory data in the patients

Data expressed as mean (SD). P value was significant if< 0.05 (paired t test was used for comparison). PT: prothrombin time; PC: prothrombin concentration; INR: international randomized ratio; ALT: alanine transaminase; AST: aspartate transaminase; HCV-RNA: hepatitis C virus- ribonucleic acid

Table (3): Baseline and post-therapy PBMC phenotypes in the patients

Data expressed as mean (SD). P value was significant if< 0.05 (paired t test was used for comparison). PBMC: peripheral mononuclear cell; CD: cluster differentiation

Table (4): Correlation of viral load with other parameters in the study at the baseline

Data expressed as r (strength of correlation), P (significance of correlation). P value was significant if< 0.05 (Pearson correlation was used). CD: cluster differentiation

DISCUSSION

Direct acting analogues with high efficacy DAA-based therapies have been game changers in the treatment of HCV infection. DAA treatment may modify the altered host immune response by eradicating the hepatitis C virus [9]. The immune system response following HCV clearance, on the other hand, is unknown. As a result, our research focused on changes in haematological profiles and PBMC during DAA therapy.

The current longitudinal, observational cohort study included 100 patients with chronic HCV and was eligible for therapy with DAAs in form of SOF with DAC. Mean age of those patients was 44.87 ± 14.55 years and majority (68%) of them was males. Sustained virological response (SVR) was obtained in all patients with no reported side effects in majority of patients.

This study was agreed with previous studies that reported high efficacy and safety of DAAs in the treatment of chronic HCV infection. For HCV infections, DAAs-based therapy provides a sustained virologic response in ≥95% of treated persons with fewer side effects [10-12, 13].

In terms of haematological changes in the current study, it was discovered that parameters of the complete blood picture showed insignificant differences when comparing baseline data and follow-up data. The most commonly reported adverse effects were anaemia, thrombocytopenia, and leucopenia, which may necessitate dose adjustment in some patients [13,14]. In our cohort, anaemia wasn’t reported may be due to none of those patients received ribavirin.

In the current study, there was a significant reduction in the levels of alanine transaminase and aspartate transaminase after therapy, but no changes in other parameters of liver function tests. In line with our findings, Babatin et al. and Abdel-Aziz et al. reported that SOF/DCV with or without RBV was associated with decreased liver transaminases and fibrosis in HCV GT4 patients. This improvement could be accompanied by a significant improvement in liver fibrosis [15,16].

Our study revealed that viral load had insignificant correlations with other parameters with exception of significant negative correlation with hemoglobin (r=-0.45; P< 0.001), RBCs (r=-0.46; P< 0.001), Hct (r=-0.48; P< 0.001), and CD3⁺ CD8⁺ cells (r=-0.30; P< 0.001). Generally, there are lacking in published data about correlations of HCV viral load with other parameters. Fayed et al found that viral load had positive correlations with liver enzymes, inflammatory monocytes and degree of fibrosis with inverse correlation with serum albumin level [17].

The current work revealed a significant reduction in CD³ cells (69.99 ± 3.81 vs. 59.17 ± 5.97%; P< 0.001), CD⁴ cells (40.01 ± 4.76 vs. 36.40 ± 4.36 %; P< 0.001), CD⁸ cells (29.96 ± 4.30 vs. 26.78 ± 4.45 %; P< 0.001), CD³ CD⁴ cells (39.69 ± 2.82 vs. 30.27 ± 2.82 %; P< 0.001) and CD³ CD⁸ cells (24.27 ± 2.82 vs. 17.50 ± 2.36 %; P< 0.001) after therapy in comparison to baseline data.

Chronic HCV infection maintains T cell exhaustion phenotypes while increasing regulatory T cell (Treg) frequency of function. T cell exhaustion is characterised by excessive activation, high apoptosis, and decreased proliferation. T cells that have been exhausted have higher levels of the CD28 family. During HCV infection, circulating Tregs increase and suppress CD4+ and CD8+ T cell responses and functions [18].

DAA-based therapy may restore altered immune subsets, as well as exhaustion and activation phenotypes similar to those seen in healthy people. Following therapy, numerous studies show a reversal in NK cell subset distribution, as well as decreases in NK cell activation states and T cell exhaustion phenotypes [19,20,21].

Our results were consistent with previous Egyptian study revealed that demonstrated that the administration of SOF-based therapy regimens could reduce the percentage of CD3⁺, CD4⁺ and CD3⁺CD8⁺ cells as compared to the baseline. They also, found that a significant increase percentage of CD14⁺cells, with no significant effects on the CD20⁺cells [13].

Furthermore, SOF/DCV therapy was found to significantly reduce the number of pro-inflammatory monocytes. This could be due to suppressed monocyte activation and maturation, downregulation of CD16, and/or decreased turnover and tracking of this subset of myeloid cells from the bone marrow [17].

These results were also, consistent with previous  report  that  demonstrated  significant decrease  of  CD4⁺ and  CD8⁺T  cells,  and  of  their  CD45RO⁺ and  CD45RA ⁺ subpopulations,  in  HCV/HIV  co-infected  patients treated with RBV and peg-IFN-α [22].

Several mechanisms have been proposed to contribute to immune dysfunction, including the immunoregulatory properties of HCV proteins, the availability of CD4 T cell assistance, and an increase in the number of CD4+ CD25+ Treg cells. Furthermore, galectin-9 (Gal-9), a TIM-3 ligand, is upregulated by Kupfer cells and monocytes in HCV and promotes the expansion of CD4+ regulatory T cells[9].

It was also discovered that SOF-based therapy regimens (SOF and RBV or SOF, RBV, and peg-IFN—2a) induced apoptosis in PBMCs. The proliferative capacity of PBMCs was significantly reduced in both regimens, while the percentage of apoptotic cells was significantly increased [13].

DAA-based therapy, however, does not restore NK and T cell function, normalise NK subsets and activation states, or reduce Treg frequency, according to studies. Furthermore, it is unknown what clinical or demographic factors may influence the immune system after viral eradication, which is an important factor to consider when using DAA st-based therapy [19, 23,20].

The main limitations included; 1) relatively small sample size, 2) short term of follow up and 3) didn’t included different regimens of DAAs. So, its recommended to perform such results on large scale of patients with different regimens of DAAs.

CONCLUSION

In patients with chronic HCV infection, SOF and DAC are tolerable, safe, ‎and effective agents. Nonetheless, this combination has the potential to alter ‎the proliferation of different subsets of peripheral mononuclear cells. Future ‎research should compare the immunological effects of different DAA ‎regimens.

Ethical consideration:

Permission and official approval to carry out the study was obtained. All patients signed a written informed consent before inclusion into this study and the institutional ethical committee at Faculty of Medicine, Assiut University, approved the study. The study protocol conforms with the ethical guidelines of the 1975 Declaration of Helsinki.

Conflict of interest:

No.

Acknowledgments:

No.

Funding:

No.