Expression of human ficolin-2 in hepatocytes confers resistance to infection by diverse hepatotropic viruses

The liver-expressed pattern recognition receptors (PRRs) mannose binding lectin (MBL), ficolin-2 and ficolin-3 contribute to the innate immune response by activating complement. Binding of soluble ficolin-2 to viral pathogens can directly neutralize virus entry. We observed that the human hepatoma cell line HuH7.5, which is routinely used for the study of hepatotropic viruses, is deficient in expression of MBL, ficolin-2 and ficolin-3. We generated a cell line that expressed and secreted ficolin-2. This cell line (HuH7.5 [FCN2]) was more resistant to infection with hepatitis C virus (HCV), ebolavirus (EBOV) and vesicular stomatitis virus (VSV), but surprisingly was more susceptible to infection with rabies virus (RABV). Cell-to-cell spread of HCV was also inhibited in ficolin-2 expressing cells. This illustrates that ficolin-2 expression in hepatocytes contributes to innate resistance to virus infection, but some viruses might utilise ficolin-2 to facilitate entry

Nanopore sequencing from extraction-free direct PCR of dried serum spots for portable hepatitis B virus drug-resistance typing

© 2020 Background: Effective drug regimens for the treatment of hepatitis B virus (HBV) infections are essential to achieve the World Health Organisation commitment to eliminate viral hepatitis by 2030. Lamivudine (3TC) is widely used in countries with high levels of chronic HBV, however resistance has been shown to occur in up to 50 % of individuals receiving continuous monotherapy for 4 years. Telbivudine (LdT) is now more commonly used in place of lamivudine but is ineffective against 3TC-resistant HBV. Genotyping and identification of resistanceassociated substitutions (RAS) is not practical in many locations. Objectives: A novel assay was designed to enable HBV genotyping and characterisation of resistance mutations directly from serum samples stored on filter paper, using Sanger and MinION sequencing. Study design: The assay was applied to a cohort of 30 samples stored on filter paper for several years with HBV viral loads ranging from 8.2 × 108 to 635 IU/mL. A set of 6 high-titre samples were used in a proof-of-principle study using the MinION sequencer. Results: The assay allowed determination of HBV genotype and elucidation of RAS down to 600 IU/mL using a 550bp amplicon. Sequencing of a 1.2 kb amplicon using a MinION sequencer gave results consistent with Sanger sequencing and allowed the identification of minor populations of variants. Conclusions: We present two approaches for reliable HBV sequencing and RAS identification using methods suitable for resource-limited environments. This is the first demonstration of extraction-free DNA sequencing direct from DSS using MinION and these workflows are adaptable to the investigation of other DNA viruses

SARS-CoV-2 vaccine breakthrough reinfection in a health-care worker of Iraq: A case report

The COVID-19 pandemic has severely affected the entire globe since the first isolation of SARS-CoV-2 from patients with severe respiratory illness in Wuhan, China. Although the global vaccination drive is in full swing, many cases of reinfection have also been reported after vaccination. Currently, there is a scarcity of data available on the reinfection and vaccine breakthrough infections in Iraq. In this letter, we have presented a case report on the SARS-CoV-2 vaccine breakthrough reinfection in a health-care worker after completion of the double-dose vaccination. An increased symptom severity was reported on the second infection, which was confirmed to be of Delta variant. Such vaccine breakthrough infection reports have raised important questions regarding the duration of vaccine-mediated immunity and vaccine effectiveness against all circulating variants. These have further emphasized the importance of following non-pharmaceutical interventions by fully vaccinated individuals, especially at health-care settings

SARS-CoV-2 Omicron Variant Genomic and Phylogenetic Analysis in Iraqi Kurdistan Region

Omicron variants have been classified as Variants of Concern (VOC) by the World Health Organization (WHO) ever since they first emerged as a result of a significant mutation in this variant, which showed to have an impact on transmissibility and virulence of the virus, as evidenced by the ongoing modifications in the SARS-CoV-2 virus. As a global pandemic, the Omicron variant also spread among the Kurdish population. This study aimed to analyze different strains from different cities of the Kurdistan region of Iraq to show the risk of infection and the impact of the various mutations on immune responses and vaccination. A total of 175 nasopharyngeal/oropharyngeal specimens were collected at West Erbil Emergency Hospital and confirmed for SARS-CoV-2 infection by RT-PCR. The genomes of the samples were sequenced using the Illumina COVID-Seq Method. The genome analysis was established based on previously published data in the GISAID database and compared to previously detected mutations in the Omicron variants, and that they belong to the BA.1 lineage and include most variations determined in other studies related to transmissibility, high infectivity and immune escape. Most of the mutations were found in the RBD (receptor binding domain), the region related to the escape from humoral immunity. Remarkably, these point mutations (G339D, S371L, S373P, S375F, T547K, D614G, H655Y, N679K and N969K) were also determined in this study, which were unique, and their impact should be addressed more. Overall, the Omicron variants were more contagious than other variants. However, the mortality rate was low, and most infectious cases were asymptomatic. The next step should address the potential of Omicron variants to develop the next-generation COVID-19 vaccine