Polymorphisms in the Th17 cell-related RORC gene are associated with spontaneous clearance of HCV in Chinese women

Genetic variation in FOXP3 and ROR-γ genes in pediatric acute lymphocytic leukemia (ALL) patients: correlation with associated cytokines

BACKGROUND

FOXP3 and ROR-γ genes are master regulators of the Treg and Th17 differentiation, respectively. This work was planned to investigate the impact of FOXP3 (rs3761548C/A and rs3761549C/T) and ROR-γ (rs9017A/G & rs9826A/G) gene polymorphism on the vulnerability of pediatric Egyptians to acute lymphoblastic leukemia (ALL). Furthermore, we evaluated the impact of these genetic variations on Treg/Th17-related cytokines.

METHODS

FOXP3 SNPs were genotyped using PCR-based restriction fragment length polymorphism (PCR-RFLP), while ROR-γ SNPs polymorphism were performed by PCR-sequence-specific primer (PCR-SSP). An Enzyme-linked immunosorbent assay (ELISA) was used to assess the levels of Treg/Th17 associated cytokines on 128 ALL children and 124 healthy donors.

RESULTS

Compared to controls, patients had a significant increase (p < 0.01/p < 0.05) in FOXP3rs3761548CC genotype and a significant decrease (p < 0.001/p < 0.01) inrs3761548CA genotype. A significant elevation (p < 0.001/p < 0.01) in ROR-γ rs9017AA genotype and a significant reduction (p < 0.01/p < 0.05) in rs9017AG genotype were detected in ALL patients versus controls. An insignificant change in FOXP3 (rs3761549C/T) and ROR-γ (rs9826A/G) genotypes was demonstrated between both groups. ROR-γ GG and GA haplotypes were significantly decreased (p < 0.05/p < 0.05; p < 0.05/p < 0.05) in ALL subjects compared to healthy ones. Relapsed patients had a significantly higher (p < 0.05/P < 0.05) frequency of FOXP3 rs3761548CA genotype than non-relapsed subjects. ROR-γ rs9017AG and rs9826GG genotypes might be associated with the increase in IL-23 plasma level.

CONCLUSIONS

Our preliminary data provided evidence for the impact ofFOXP3 (rs3761548C/A) and ROR-γ (rs9017A/G) gene polymorphisms and the occurrence of ALL in Egyptian children. Another large-scale prospective study should be conducted to validate these findings.

Chronic Hepatitis C Virus Infection Modulates the Transcriptional Profiles of CD4+ T Cells

Background

Chronic hepatitis C (CHC) is associated with altered cell-mediated immune response.

Objective

The aim of the study was to characterize functional alterations in CD4⁺ T cell subsets and myeloid-derived suppressor cells (MDSCs) during chronic hepatitis C virus (HCV) infection. Methodology. The expression levels of the lineage-defining transcriptional factors (TFs) T-bet, Gata3, Rorγt, and Foxp3 in circulating CD4⁺ T cells and percentages of MDSCs in peripheral blood were evaluated in 33 patients with CHC, 31 persons, who had spontaneously cleared the HCV infection, and 30 healthy subjects. Analysis. The CD4+ T cells TFs T-bet (T-box expressed in T cells), Foxp3 (Forkhead box P3 transcription factor), Gata3 (Gata-binding protein 3), and Rorγt (retinoic-acid-related orphan receptor gamma) and activation of CD8+ T cells, as well as percentages of MDSCs, were measured by multicolor flow cytometry after intracellular and surface staining of peripheral blood mononuclear cells with fluorescent monoclonal antibodies.

Result

The patients with CHC had significantly lower percentages of CD4⁺ T cells expressing Rorγt and Gata3 and higher percentages of Foxp3-expressing CD4⁺ T cells than healthy controls and persons who spontaneously cleared HCV infection. The ratios of T-bet⁺/Gata3⁺ and Foxp3⁺/Rorγt⁺ CD4⁺ T cells were the highest in the patients with CHC. In the patients with CHC, the percentages of Gata3⁺ and Rorγt⁺ CD4⁺ T cells and the percentages of T-bet⁺ CD4⁺ T cells and CD38⁺/HLA-DR⁺ CD8⁺ T cells demonstrated significant positive correlations. In addition, the percentage of CD38⁺/HLA-DR⁺ CD8⁺ T cells correlated negatively with the percentage of MDSCs.

Conclusion

Chronic HCV infection is associated with downregulation of TFs Gata3 and Rorγt polarizing CD4+ T cells into Th2 and Th17 phenotypes together with upregulation of Foxp3 responsible for induction of regulatory T cells suppressing immune response.