Mannose binding lectin gene 2 (rs1800450) missense variant may contribute to development and severity of COVID-19 infection

Background/objectives

COVID-19 followed a mortal course in some young patients without any underlying factors, however, it followed a very benign course in some very older individuals with multiple comorbidities. These observations question if some genetic factors may be related to the vulnerability and poor prognosis of the disease. In this study, we aimed to investigate whether MBL2 gene B variant at codon 54 (rs1800450) were related to the variabilities in clinical course of this infection.

Methods

284 PCR-confirmed COVID-19 patients and 100 healthy controls were included in the study. COVID-19 patients were subdivided according to the clinical features and clinical characteristics were analyzed. DNAs of all patients and controls were examined for the codon 54 A/B (gly54asp: rs1800450) variation in exon 1 of the MBL2 gene.

Results

In univariate analysis, BB genotype of MBL2 gene was more common among COVID-19 cases compared with controls (10.9% vs 1.0%, respectively; OR = 12.1, 95%CI = 1.6–90.1, p = 0.001). Multivariate analyses, adjusted for age, sex and MBL genetic variants, revealed that when compared with the COVID-19 patients that had AA genotype (reference), the patients that had BB or AB genotypes suffered from a higher risk for severe disease (for BB genotype, odds ratio (OR) = 5.3, p < 0.001; for AB genotype, OR = 2.9, p = 0.001) and for ICU need (for BB genotype, OR = 19.6, p < 0.001; for AB genotype, OR = 6.9, p = 0.001). On the other hand, there was not any significant difference between the genotype variants in terms of mortality at 28 days or development of secondary bacterial infection.

Conclusion

The B variants of MBL2 gene at codon 54, which were associated with lower MBL2 levels, were related to a higher risk for a more severe clinical course of COVID-19 infection in some respects. Our findings may have potential future implications, e.g. for use of MBL protein as potential therapeutics or prioritize the individuals with B variants during vaccination strategies.

Serum ficolin-2 concentrations are significantly changed in patients with hepatitis B virus infection and liver diseases

Human ficolin-2 is an important lectin complement pathway activator that is secreted from liver cells and has been implicated as an anti-infection innate immune molecule. However, the role of ficolin-2 protein and its dynamic changes over the course of and in the prognosis of chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) remain unclear. In this study, we analyzed ficolin-2 protein expression in a cohort of individuals with CHB infection, HCC and cirrhosis. A sandwich enzyme-linked immunosorbent assay (ELISA) method was used to measure serum ficolin-2 concentrations. Ficolin-2 expression in liver tissues was detected by immunohistochemical staining. Serum ficolin-2 concentrations in CHB patients were significantly higher than in healthy controls and HBV carriers. After 48 weeks of routine amelioration liver function treatment, serum ficolin-2 concentrations decreased and were positively correlated with favorable alanine aminotransferase (ALT), HBV DNA and HBeAg-seroconversion outcomes. Interestingly, we observed much lower expression of serum and intrahepatic ficolin-2 in HCC and cirrhosis compared with healthy controls. Our findings suggest that serum and intrahepatic ficolin-2 levels may be considered one of the indicators for the response of chronic HBV infection, HCC and cirrhosis.

Serum Soluble CD14 in Egyptian Patients with Chronic Hepatitis C: Its Relationship to Disease Progression and Response to Treatment

Hepatitis C virus (HCV) is a major public health problem. Soluble CD14 (sCD14) level was shown to be associated with HCV infection. In this study, we aimed to investigate the relationship between sCD14 concentration and disease progression, as well as the response to pegylated interferon/ribavirin (peg-IFN/RBV) therapy in Egyptian patients with chronic hepatitis C (CHC). The ELISA technique was used to test 80 patients with CHC and 20 healthy control persons for serum levels of sCD14 (pretreatment and after 12 weeks of treatment). CHC patients were 65 males and 15 females. Normal healthy controls included 20 age- and sex-matched volunteers. The mean age of the CHC patients was 39.94 years, while that of the controls was 39.2 years The serum sCD14 level was significantly higher in chronic HCV-infected patients (3.6±0.18 μg/mL) compared to healthy control subjects (3.1±0.18 μg/mL). The serum sCD14 level was significantly directly correlated with the hepatic fibrosis score (r=0.24, P=0.03), histological activity index (r=0.26, P=0.02), and serum aminotransferases [r=0.28, P=0.005 for alanine aminotransferase (ALT) and r=0.30, P=0.003 for aspartate aminotransferase (AST)]. The pretreatment sCD14 level was not significantly correlated to the treatment response, but it increased after 12 weeks of peg-IFN/RBV therapy and values were significantly higher in nonresponders (P=0.02). The pretreatment sCD14 level cannot predict the treatment response in chronic HCV patients receiving peg-IFN/RBV therapy. However, the serum sCD14 level after 12 weeks of treatment can serve as a negative predictor of treatment response.

Human lectins and their roles in viral infections

Innate recognition of virus proteins is an important component of the immune response to viral pathogens. A component of this immune recognition is the family of lectins; pattern recognition receptors (PRRs) that recognise viral pathogen-associated molecular patterns (PAMPs) including viral glycoproteins. In this review we discuss the contribution of soluble and membrane-associated PRRs to immunity against virus pathogens, and the potential role of these molecules in facilitating virus replication. These processes are illustrated with examples of viruses including human immunodeficiency virus (HIV), hepatitis C virus (HCV) and Ebola virus (EBOV). We focus on the structure, function and genetics of the well-characterised C-type lectin mannose-binding lectin, the ficolins, and the membrane-bound CD209 proteins expressed on dendritic cells. The potential for lectin-based antiviral therapies is also discussed.

Anti-C1q in chronic hepatitis C virus genotype IV infection: association with autoimmune rheumatologic manifestations

A growing body of evidence suggests that anti-complement-1q (anti-C1q) antibodies are elevated in a variety of autoimmune disease. Therefore, we investigated their prevalence and clinical significance in plasma of patients with hepatitis C virus (HCV) genotype IV in the presence and absence of autoimmune extra hepatic manifestations in comparison to normal healthy individuals. Plasma Anti-C1q Abs levels were assessed by an Enzyme Linked Immunosorbant Assay in 91 chronic HCV-infected patients (51 with and 40 without autoimmune rheumatic manifestations) and 40 healthy volunteers matched for age and gender. Epidemiological, clinical, immunochemical and virological data were prospectively collected. Positive Anti-C1q antibodies were more frequent among HCV patients with extra-hepatic autoimmune involvement, than those without and healthy control subjects. No significant correlations were found between Anti-C1q levels with either the liver activity or the fibrosis scores. In HCV-patients with autoimmune involvements, plasma Anti-C1q levels were significantly higher in patients with positive cryoglobulin, and in those with lymphoma than in those without. These results were confirmed by multivariate analysis. Further large scale longitudinal studies are required to assess and clarify the significance and the pathogenic role of anti-C1q antibodies among HCV infected patients with positive cryoglobulinaemia and lymphoma.

Early increased ficolin-2 concentrations are associated with severity of liver inflammation and efficacy of anti-viral therapy in chronic hepatitis C patients

Ficolin-2 is a kind of human serum complement lectin with a structure similar to mannan-binding lectin (MBL), and it has been implicated in innate immunity. Recent studies have shown that complement pathway activation may contribute to hepatitis. However, the relationship between ficolin-2 and viral hepatitis remains largely elusive. The aim of this study was to determine the dynamics of ficolin-2 in patients with chronic hepatitis C. Forty nine patients who had not yet received therapy [24 patients with abnormal alanine aminotransferase (ALT) levels (>40 U/L) and 25 patients with normal ALT levels (≤ 40 U/L)], 28 patients with hepatitis C who received therapy for 2 weeks and 16 patients received therapy for a full month or longer were included in the study. A sandwich enzyme-linked immunosorbent assay (ELISA) was used to measure the ficolin-2 concentrations in all serum samples of patients and 42 healthy donors. We found the concentrations of ficolin-2 were significantly higher in chronic hepatitis C patients with abnormal ALT values than in chronic hepatitis C patients with normal ALT values and healthy controls. Ficolin-2 concentrations in chronic hepatitis C patients with abnormal ALT values were positively correlated with ALT levels (P < 0.05). After therapy, the concentrations of ficolin-2 decreased and accompany with ALT and Hepatitis C virus (HCV) RNA levels. Then, we found ficolin-2 concentrations in rapid viral response (RVR) group decreased significantly (P < 0.05), while in non-RVR group, ficolin-2 decreased slightly (P > 0.05). Our findings suggest that early increased ficolin-2 is highly correlated with hepatic inflammation and rapid viral response.