Evaluation of MX1 Gene Promoter Methylation in Different Severities of COVID-19 Considering Patient Gender.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), led to a pandemic in March 2020. During a viral infection, it has been reported that epigenetic changes occur for both sides: Infected cells elicit an antiviral environmental response, which induces and initiates certain pathways for proper response to the virus, while the virus silences the expression of vital genes in the anti-viral host cell. In this study, we aimed to examine the methylation level of the MX1 gene promoter in different stages in COVID-19 patients compared to the control group. METHODS: In total, 470 COVID-19 patients with a positive polymerase chain reaction (PCR) test (235 women and 235 men) were recruited into the study as the test group. Patients were divided based on the World Health Organization (WHO) classification into three groups: moderate, severe, and critical. Moreover, 100 healthy individuals (50 women and 50 men) were selected as the control group. Peripheral white blood cells were collected and PCR was performed using two types of primers designed for methylated and unmethylated states of the MX1 gene. The PCR products were then loaded on agarose gel and the band intensities were calculated by ImageJ software. RESULTS: The results showed a decrease in the methylation of the MX1 gene promoter in moderate and severe groups and an increase in the MX1 gene promoter methylation in the critical group. In addition, the level of methylation was higher in men than in women. CONCLUSIONS: Increased methylation of the MX1 gene in the critical group may indicate the role of SARS-CoV-2 in reducing the expression levels of this antiviral gene and thus promoting virus replication and disease progression.

Influence of Disease Severity and Gender on HLA-C Methylation in COVID-19 Patients.

In the pathophysiology of COVID-19, immunomodulatory factors play a vital role. Viruses have epigenetic effects on various genes, particularly methylation. Explaining the changes in immunological factor methylation levels during viral infections requires substantial consideration. HLA-C is a crucial determinant of immune function and NK cell activity and is primarily implicated in viral infections. This research focused on studying HLA-C methylation in COVID-19 patients with different severity. Peripheral blood samples were collected from 470 patients (235 men and 235 women) with RT-qPCR-confirmed COVID-19 test and classified into moderate, severe, and critical groups based on WHO criteria. Also, one hundred (50 men and 50 women) healthy subjects were selected as the control group. Peripheral blood mononuclear cells were used for DNA extraction, and the methylation-specific PCR (MSP) method and gel electrophoresis were used to determine the methylation status of the HLA-C. Significant statistical differences in HLA-C methylation were observed among cases and controls and various stages of the disease. HLA-C methylation in men and women has decreased in all stages (p < 0.05). In comparison with control, HLA-C methylation in both genders were as follows: moderate (women: 41.0%, men: 52.33%), severe (women: 43.42%, men: 64.86%), critical (women: 42.33%, men: 60.07%), and total patients (women: 45.52%, men: 56.97%). Furthermore, the methylation levels in men were higher than in women in all groups (p < 0.05). Significantly, among all groups, the severe group of men participants showed the highest methylation percentage (p < 0.05). No significant differences were detected for different disease severity in the women group (p > 0.1). This study found that HLA-C methylation was significantly lower in COVID-19 patients with different disease severity. There were also significant differences in HLA-C methylation between men and women patients with different severity. Therefore, during managing viral infections, particularly COVID-19, it is critical to consider patient gender and disease severity.

CCR2 and DPP9 expression in the peripheral blood of COVID-19 patients: Influences of the disease severity and gender.

INTRODUCTION: Hyper-inflammatory reactions play a crucial role in the pathogenesis of the severe forms of COVID-19. However, clarification of the molecular basis of the inflammatory-related factors needs more consideration. The aim was to evaluate the gene expression of two fundamental molecules contributing to the induction of inflammatory like CCR2 and DPP9 in cells from peripheral blood samples from patients with various patterns of COVID-19. METHODS: Peripheral blood samples were collected from 470 patients (235 male and 235 female) with RT-qPCR-confirmed COVID-19 test exhibiting moderate, severe, and critical symptoms based on WHO criteria. 100 healthy subjects (50 male and 50 female) were also enrolled in the study as a control group. The gene expression of DPP-9 and CCR-2 was assessed in the blood samples using real-time PCR method. RESULTS: The COVID-19 patients in severe stage expressed higher levels of CCR2 and DPP9 compared with healthy controls. In male and female patients, the levels of CCR2 and DDP9 expression significantly differed between moderate, severe, and critical patterns (p < 0.0001) as well as between each COVID-19 form and control group (p < 0.0001). The male patients with severe COVID-19 expressed greater levels of CCR2 and DPP-9 than female with same disease form. The female patients with moderate and critical COVID-19 expressed greater levels of CCR2 and DPP-9 than male patients with same disease stage. CONCLUSION: We demonstrated that the expression of DPP-9 and CCR-2 was substantially increased in COVID-19 patients with different forms of disease. Considerable differences were also demonstrated between male and female with different patterns of disease. Therefore, we suggest to consider the gender of patients and disease severity for management of COVID-19.