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The antiviral activity of recombinant human IFN-lambda type 1 (IFNλ-1) against culture strain of SARS-CoV-2 virus was determined by infecting a highly sensitive VeroE6 coronavirus cell culture after preincubation test (the cell monolayer was incubated with 4-fold dilutions of IFNλ-1 in a concentration range of 0.16-42,500 ng/ml in a culture medium for 12 h at 37°C) and without preincubation (simultaneous addition of different concentrations of IFNλ-1 and SARS-CoV-2 infection in a dose of 102 TCID50). The created recombinant human IFNλ-1 demonstrated obvious antiviral activity against SARS-CoV-2 virus in vitro. In the tests with and without preincubation, IFNλ-1 exhibited significant activity, although somewhat lower in variant with simultaneous addition of IFNλ-1 and virus to the cell culture. It should be noted that the antiviral effect of IFNλ-1 was observed in a wide range of concentrations., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Different methods for producing bulk quantities of concentrated and purified SARS-CoV-2 for the use as antigens and for the research into COVID-19 biology were tested., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Simian immunodeficiency virus (SIV)-infected macaque is a widely used model to study human immunodeficiency virus. The purpose of the study is to discover the amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) changes in SIV-infected macaques. Seven rhesus macaques were involved in the longitudinal MRI scans: (1) baseline (healthy state); (2) SIV infection stage (12 weeks after SIV inoculation). ALFF and fALFF were subsequently computed and compared to ascertain the changes caused by SIV infection. Whole-brain correlation analysis was further used to explore the possible associations between ALFF/fALFF values and immune status parameters (CD4+ T cell counts, CD4/CD8 ratio and virus load). Compared with the baseline, macaques in SIV infection stage displayed strengthened ALFF values in left precuneus, postcentral gyrus, and temporal gyrus, and weakened ALFF values in orbital gyrus and inferior temporal gyrus. Meanwhile, increased fALFF values were found in left superior frontal gyrus, right precentral gyrus, and superior temporal gyrus, while decreased fALFF values existed in left hippocampus, left caudate, and right inferior frontal gyrus. Furthermore, ALFF and fALFF values in several brain regions showed significant relationships with CD4+ T cell counts, CD4/CD8 ratio, and plasma virus load. Our findings could promote the understanding of neuroAIDS caused by HIV infection, which may provide supplementary evidences for the future therapy study in SIV model.

Human herpes virus-6 (HHV-6) and human herpes virus-7 (HHV-7) are immunomodulating viruses potentially affecting the nervous system. We evaluated the influence of HHV-6 and HHV-7 infections on fibromyalgia (FM) clinical course. Forty-three FM patients and 50 control group participants were enrolled. 39.50% (n = 17) FM patients had light A delta and C nerve fiber damage, 27.91% (n = 12) had severe A delta and C nerve fiber damage. 67.44% (n = 29) FM patients had loss of warm sensation in feet, loss of heat pain sensation, and increased cold pain sensation (34.90%, n = 15 in both findings). HHV-6 and HHV-7 genomic sequences in peripheral blood DNA in 23/43 (51.00%) and 34/43 (75.50%) of samples from FM patients and in 3/50 (6.00%) and 26/50 (52.00%) of samples from the control group individuals were detected. Active HHV-6 (plasma viremia) or HHV-7 infection was revealed only in FM patients (4/23, 17.40% and 4/34, 11.80%, respectively). A statistically significant moderate positive correlation was found between A delta and C nerve fiber damage severity and HHV-6 infection (p < 0.01, r = 0.410). 23/43 patients from the FM group and control group participants HHV-6 and 34/45 HHV-7 did have infection markers. A statistically significant moderate positive correlation was found between A delta and C nerve fiber damage severity and HHV-6 infection (p < 0.01, r = 0.410). No difference was found between detection frequency of persistent HHV-6 and HHV-7 infection between FM patients and the control group. Statistically significant correlation was observed between quantitation of changes in QST thermal modalities and HHV-6 infection. There was no correlation between A delta and C nerve fiber damage and HHV-7 infection.

Background: Epstein-Barr virus (EBV) was the first human virus identified to express microRNA (miRNA). To date, 44 mature miRNAs are encoded for within the EBV genome. EBV miRNAs have not been profiled in paediatric renal transplant recipients. In this study, we investigated circulating EBV miRNA profiles as novel biomarkers in paediatric renal transplant patients., Methods: Forty-two microRNAs encoded within 2 EBV open reading frames (BART and BHRF) were examined in renal transplant recipients who resolved EBV infection (REI) or maintained chronic high viral loads (CHL), and in non-transplant patients with acute infectious mononucleosis (IM)., Results: Plasma EBV-miR-BART2-5p was present in higher numbers of IM (7/8) and CHL (7/10) compared to REI (7/12) patients. A trend was observed between the numbers of plasma EBV miRNAs expressed and EBV viral load (p < 0.07). Several EBV-miRs including BART7-3p, 15, 9-3p, 11-3p, 1-3p and 3-3p were detected in IM and CHL patients only. The lytic EBV-miRs, BHRF1-2-3p and 1-1, indicating active viral replication, were detected in IM patients only. One CHL patient developed post-transplant lymphoproliferative disease (PTLD) after several years and analysis of 10 samples over a 30-month period showed an average 24-fold higher change in plasma EBV-miR-BART2-5p compared to the CHL group and 110-fold higher change compared to the REI group., Conclusions: Our results suggest that EBV-miR-BART2-5p, which targets the stress-induced immune ligand MICB to escape recognition and elimination by NK cells, may have a role in sustaining high EBV viral loads in CHL paediatric kidney transplant recipients.

Purpose: Human papilloma virus (HPV) infection is associated with several anogenital malignancies. Here, we set out to evaluate digital droplet PCR (ddPCR) as a tool for HPV 16, 18, 33 and 45 viral load quantification and, in addition, to compare the efficacy of the ddPCR assay for HPV 16 detection with that of quantitative real-time PCR (qPCR)., Methods: Clinical samples, positive for HPV genotypes 16, 18, 33 and 45 were analyzed for viral load using ddPCR. Sample DNA was cleaved before droplet generation and PCR. Droplets positive for VIC and FAM fluorescence were read in a QX200 Droplet reader™ (BIO-RAD) after which the viral load was calculated using Quantasoft software., Results: We found that DNAs extracted from formalin fixed paraffin embedded (FFPE) tissue samples yielded lower amplification signals compared to those obtained from liquid based cytology (LBC) samples, but they were clearly distinguishable from negative background signals. The viral limit of detection was 1.6 copies of HPV 16, 2.8 copies of HPV 18, 4.6 copies of HPV 33 and 1.6 copies of HPV 45. The mean inter-assay coefficients of variability (CV) for the assays ranged from 3.4 to 7.0%, and the mean intra-assay CV from 2.6 to 8.2%. The viral load in the different cohorts of tumor samples ranged from 154 to 340,200 copies for HPV 16, 244 to 31,300 copies for HPV 18 and 738 to 69,100 copies for HPV 33. One sample positive for HPV 45 contained 1331 viral copies. When comparing qPCR data with ddPCR copy number data, the qPCR values were found to be 1 to 31 times higher., Conclusions: Separation of fragments in nanodroplets may facilitate the amplification of fragmented human and viral DNA. The method of digital droplet PCR may, thus, provide a new and promising tool for evaluating the HPV viral load in clinical samples.

HTLV-1 proviral load (pvl) is an important risk marker for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), but its value as prognostic marker is not well defined. Long-term prospective cohort studies are necessary to clarify this question. Here, we analyzed HTLV-1 pvl in the peripheral blood of 82 asymptomatic carriers (AC; 351 samples), 12 HAM/TSP patients (HAM; 46 samples), and six incident cases of HAM/TSP (iHAM), with serial samples collected before (n = 10) and after (n = 20) the disease onset. The mean interval of follow-up was 10 years in the AC group and 8 years in HAM and iHAM groups. pvl was not significantly different between the first and last measurements in the three groups, but there was a trend to decrease over time. Coefficient of variation of pvl was significantly lower in the AC group than in HAM (p = 0.015) and iHAM (p = 0.022) patients. AC and HAM individuals showed a significant and strong positive correlation between the first and last measurements of pvl, but not iHAM subjects. All individuals who developed HAM/TSP during the follow-up had high pvl level (>1 %) before the onset of disease, but a typical increase in pvl was not observed in that period. The data suggest that there is a trend to reach an equilibrium plateau of pvl over time, characteristic of each individual. A significant rate of AC keeps high pvl levels for a long time without developing clinical symptoms associated to HTLV-1 infection. Thus, serial quantification of pvl in the peripheral blood does not seem to be a good prognostic marker for HAM/TSP.

Primary simian varicella virus (SVV) infection in non-human primates causes varicella, after which the virus becomes latent in ganglionic neurons and reactivates to cause zoster. The host response in ganglia during establishment of latency is ill-defined. Ganglia from five African green monkeys (AGMs) obtained at 9, 13, and 20 days post-intratracheal SVV inoculation (dpi) were analyzed by ex vivo flow cytometry, immunohistochemistry, and in situ hybridization. Ganglia at 13 and 20 dpi exhibited mild inflammation. Immune infiltrates consisted mostly of CD8(dim) and CD8(bright) memory T cells, some of which expressed granzyme B, and fewer CD11c(+) and CD68(+) cells. Chemoattractant CXCL10 transcripts were expressed in neurons and infiltrating inflammatory cells but did not co-localize with SVV open reading frame 63 (ORF63) RNA expression. Satellite glial cells expressed increased levels of activation markers CD68 and MHC class II at 13 and 20 dpi compared to those at 9 dpi. Overall, local immune responses emerged as viral DNA load in ganglia declined, suggesting that intra-ganglionic immunity contributes to restricting SVV replication.

Background/purpose: Single-nucleotide polymorphisms (SNPs) around the interferon lambda 3 (IFNL3; also known as interleukin 28B; IL28B) gene are associated with spontaneous hepatitis C virus (HCV) clearance. Interferon lambda 4 (IFNL4).ss469415590, in linkage disequilibrium (LD) with IFNL3.rs12979860 among the Caucasian population, has recently been identified as a potential functional variant. Our objective was to assess the LD between IFNL3.rs12979860 and IFNL4.ss469415590 and to compare their effect on the outcome of HCV infection among Egyptians, mainly infected with HCV genotype 4., Methods: One-hundred and eighty-five Egyptian HCV patients (77 spontaneous resolvers and 108 chronic subjects), and 122 healthy controls were genotyped for both IL28B.rs12979860 and IFNL4.ss469415590. Logistic regression models including factors with univariate association with the outcome of infection were calculated for each genetic marker. The LD was also calculated for the 122 healthy controls., Results: The CC genotype of IFNL3.rs12979860 was more frequent among individuals with HCV spontaneous resolution than among those with chronic infection (57 vs. 27%; adjusted OR 3.84; 95% CI 2.02-7.30; p < 0.0001). Also, the TT/TT genotype of IFNL4.ss469415590 was more frequent among individuals with spontaneous resolution (49 vs. 20%; adjusted OR 4.17; 95% CI 2.12-8.19; p < 0.0001). Both markers were in LD (D' = 0.96; r (2) = 0.84)., Conclusion: The IFNL3.rs12979860 and IFNL4.ss469415590 variants have comparable effects on spontaneous resolution of HCV among Egyptians, for whom both markers are closely linked.

Background: This study aimed to determine whether the single-nucleotide polymorphism (rs12979860 C/T) of the interleukin 28B (IL-28B) gene, which is associated with hepatitis C virus (HCV) clearance, is also associated with fibrosis in chronic HCV infection., Methods: An RFLP-PCR technique was used to genotype 629 HCV-positive patients (200 with cirrhosis) and 428 healthy control subjects., Results: The genotype frequencies in the controls and chronic hepatitis C patients were as follows: C/C 47.0% vs. 32.6%, C/T 41.8% vs. 52.8% and T/T 11.2% vs. 14.6% (p < 0.0001). The C allele frequency was higher in HCV-2- (0.635) and 3- (0.692) infected patients in comparison to those infected with HCV-1 (0.550) or 4-5 (0.600) (p < 0.001). Infected T/T homozygotes had a mean staging score higher than other patients (3.50 vs. 3.04, p < 0.05)., Conclusions: IL-28B rs12979860 C/T polymorphism is associated with a greater likelihood of HCV persistence, particularly in HCV genotypes 1 and 4. The T allele affects the severity of liver fibrosis.

Background: PD-1, encoded by PDCD1, is highly expressed on virus-specific T cells and plays critical roles in modulating anti-virus immune responses in chronic viral infection. It is unknown, however, whether polymorphisms of the PDCD1 are associated with viral clearance during chronic viral infections., Methodology and Principal Findings: Here, we used the polymerase chain reaction-restriction fragment length polymorphism method to genotype two single nucleotide polymorphisms (SNPs) of PDCD1 in 502 patients with chronic hepatitis B virus (HBV) infection and 359 healthy controls to determine the association between PDCD1 genotypes and serum viral load as well as the risk of chronic infection. Our results showed that although neither the P7209(C/T) SNP site nor the P8737(A/G) site was associated with the risk of chronic HBV infection, the P7209 (T) allele in intron 4 is significantly associated with lower viral burden in the blood. Using a luciferase reporter assay, we demonstrated that the P7209 (T) allele creates a negative cis-element for gene transcription., Conclusions and Significance: Our data provide the first evidence that PDCD1 polymorphisms is a genetic factor in pathogenesis of chronic viral infection and reveal the functional significance of the P7209 SNP of the PDCD1.