Perturbations of the T-cell receptor repertoire in response to SARS-CoV-2 in immunocompetent and immunocompromised individuals.

BACKGROUND: Functional T-cell responses are essential for virus clearance and long-term protection after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, whereas certain clinical factors, such as older age and immunocompromise, are associated with worse outcome. OBJECTIVE: We sought to study the breadth and magnitude of T-cell responses in patients with coronavirus disease 2019 (COVID-19) and in individuals with inborn errors of immunity (IEIs) who had received COVID-19 mRNA vaccine. METHODS: Using high-throughput sequencing and bioinformatics tools to characterize the T-cell receptor ß repertoire signatures in 540 individuals after SARS-CoV-2 infection, 31 IEI recipients of COVID-19 mRNA vaccine, and healthy controls, we quantified HLA class I- and class II-restricted SARS-CoV-2-specific responses and also identified several HLA allele-clonotype motif associations in patients with COVID-19, including a subcohort of anti-type 1 interferon (IFN-1)-positive patients. RESULTS: Our analysis revealed that elderly patients with COVID-19 with critical disease manifested lower SARS-CoV-2 T-cell clonotype diversity as well as T-cell responses with reduced magnitude, whereas the SARS-CoV-2-specific clonotypes targeted a broad range of HLA class I- and class II-restricted epitopes across the viral proteome. The presence of anti-IFN-I antibodies was associated with certain HLA alleles. Finally, COVID-19 mRNA immunization induced an increase in the breadth of SARS-CoV-2-specific clonotypes in patients with IEIs, including those who had failed to seroconvert. CONCLUSIONS: Elderly individuals have impaired capacity to develop broad and sustained T-cell responses after SARS-CoV-2 infection. Genetic factors may play a role in the production of anti-IFN-1 antibodies. COVID-19 mRNA vaccines are effective in inducing T-cell responses in patients with IEIs.

A novel candidate hepatitis C virus genotype 4 subtype identified by next generation sequencing full-genome characterization in a patient from Saudi Arabia.

Background and aim: Hepatitis C virus (HCV) infection is a major global public health concern, being a leading cause of chronic liver diseases such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma. The virus is classified into 8 genotypes and 93 subtypes, each displaying distinct geographic distributions. Genotype 4 is the most predominant in the Middle East and Eastern Mediterranean and is associated with high rates of hepatitis C infection worldwide. This study used next-generation sequencing to fully characterize the HCV genome and identify a novel subtype within genotype 4 isolated from a 64-year-old Saudi man diagnosed with hepatitis C. Methods: We analyzed the complete genome of the 141-HCV isolate using whole-genome sequencing. Results: Our phylogenetic reconstructions, based on the entire genome of HCV-4 strains, revealed that the 141-HCV isolate formed a distinct group within the genotype 4 classification, providing valuable new insights into the variability of HCV. Conclusion: This discovery of a previously unclassified HCV subtype within genotype 4 sheds light on the ongoing evolution and diversity of the virus. Such knowledge has significant implications for diagnostic and therapeutic approaches, as different subtypes may exhibit varying drug sensitivities and resistance profiles.

Lack of Evidence for a Role of ACE-2 Polymorphisms as a Bedside Clinical Prognostic Marker of COVID-19.

The novel SARS-CoV-2 coronavirus causes a severe respiratory syndrome referred to as coronavirus disease (COVID-19). The angiotensin-converting enzyme 2 (ACE-2) plays an important role as a cellular receptor for SARS-CoV-2 and is largely expressed in lungs, kidneys, heart and the gastrointestinal tract along with being shed in plasma. The ACE-2 gene and protein show a high level of genetic polymorphism, including simple nucleotide variation, transcriptional variation, post-transcriptional changes, and putative protein mutations that could interfere with the binding or entry of SARS-CoV-2 and affect tissue damage in lungs or other organs. Genetic polymorphisms can impact SARS-CoV-2 viral entry and COVID-19 severity. This single-center study evaluated the possible role of the main ACE-2 polymorphisms (rs143936283, rs2285666, rs41303171, rs35803318, and rs2106809) as potential prognostic markers in SARS-CoV-2-infected individuals. Frozen whole blood was used for DNA isolation and genomic DNA samples were sheared using the Covaris LE220 Focused-ultrasonicator for targeting a peak size of 410 bp. Whole-genome sequencing libraries were generated from fragmented DNA using the Illumina TruSeq DNA PCR-Free HT Library Preparation Kit and sequenced on an Illumina NovaSeq 6000. We did not identify any correlation between ACE-2 polymorphisms and COVID-19 prognosis, suggesting that the interpretation and clinical use of ACE-2 genetic polymorphisms in real-world clinical settings requires further experimental and clinical validation.

Molecular and Genetic Characterization of Hepatitis B Virus (HBV) among Saudi Chronically HBV-Infected Individuals.

The study aimed to characterize the genotype and subgenotypes of HBV circulating in Saudi Arabia, the presence of clinically relevant mutations possibly associated with resistance to antivirals or immune escape phenomena, and the possible impact of mutations in the structural characteristics of HBV polymerase. Plasma samples from 12 Saudi Arabian HBV-infected patients were analyzed using an in-house PCR method and direct sequencing. Saudi patients were infected with mainly subgenotype D1. A number of mutations in the RT gene (correlated to antiviral resistance) and within and outside the major hydrophilic region of the S gene (claimed to influence immunogenicity and be related to immune escape) were observed in almost all patients. Furthermore, the presence of mutations in the S region caused a change in the tertiary structure of the protein compared with the consensus region. Clinical manifestations of HBV infection may change dramatically as a result of viral and host factors: the study of mutations and protein-associated cofactors might define possible aspects relevant for the natural and therapeutic history of HBV infection.

Corrigendum: Serum IgG antibodies from pregnant women reacting to mimotopes of Simian virus 40 large T antigen, the viral oncoprotein.

[This corrects the article DOI: 10.3389/fimmu.2017.00411.].

Impact of Innate Immunity, Endothelial Damage, and Metabolic Biomarkers on COVID-19 Severity and Mortality.

In this study, abnormal levels of myeloid activation, endothelial damage, and innate immune markers were associated with severe coronavirus disease 2019 (COVID-19), while higher levels of metabolic biomarkers (irisin, leptin) demonstrated a protective effect. These data support a model for COVID-19 immunopathogenesis linking robust inflammation and endothelial damage in metabolically predisposed individuals.

Increased SARS-CoV-2 seroprevalence in healthy blood donors after the second pandemic wave in South-Eastern Italy: evidence for asymptomatic young donors as potential virus spreaders.

BACKGROUND: Italy experienced SARS-CoV-2 spread during the second wave and the southern regions were severely affected. In this prospective study, we assessed the changes in SARS-CoV-2 seroprevalence rates in non-vaccinated blood donors to evaluate the spread of SARS-CoV-2 among healthy individuals in our geographical area. METHODS: 8,183 healthy blood donors visiting the Transfusion Centre at the University Hospital "Riuniti" of Foggia (Italy) to donate blood from May 2020 to March 2021 were tested twice for anti-SARS-CoV-2 antibodies by Ortho Clinical Diagnostics VITROS® 3600 through anti-SARS-CoV-2 Total and IgG reagent kit. None of the subjects had diagnosed symptomatic COVID-19 infection, and none had received vaccination. RESULTS: Overall, 516 out of 8,183 had antibodies to SARS-CoV-2 (total and IgG antibodies) (6.3%, 95% CI: 0.03-0.15%), 387 were male and 129 female. There was a significant increase of seropositive donors from May 2020 to March 2021 (p < .001). The difference in seroprevalence was significantly associated with age but not sex (2-sided p < .05 for age; 2-sided p ≥ .05 for sex) in both groups. CONCLUSIONS: Our study showed a significant increase in SARS-CoV-2 seroprevalence in blood donors and suggests that asymptomatic individuals might contribute to the spread of SARS-CoV-2. These results may contribute to revised containment measures, priorities in vaccine campaigns and monitoring of seroprevalence in public places like Transfusion Centres. Serologic testing of blood donors may be relevant to monitor SARS-CoV-2 circulation in the general population.

Genetic Subtypes and Natural Resistance Mutations in HCV Genotype 4 Infected Saudi Arabian Patients.

This study aimed to characterize the HCV genetic subtypes variability and the presence of natural occurring resistance-associated substitutions (RASs) in Saudi Arabia patients. A total of 17 GT patients were analyzed. Sequence analysis of NS3, NS5A, and NS5B regions was performed by direct sequencing, and phylogenetic analyses were used to determine genetic subtypes, RAS, and polymorphisms. Nine patients were infected by GT 4a, two with GT 4o and three with GT 4d. Two patients were infected with apparent recombinant virus (4a/4o/4a in NS3/NS5A/NS5B), and one patient was infected with a previously unknown, unclassifiable, virus of GT 4. Natural RASs were found in six patients (35%), including three infected by GT 4a, two by GT 4a/GT 4o/GT 4a, and one patient infected by an unknown, unclassifiable, virus of GT 4. In particular, NS3-RAS V170I was demonstrated in three patients, while NS5A-RASs (L28M, L30R, L28M + M31L) were detected in the remaining three patients. All patients were treated with sofosbuvir plus daclatasvir; three patients were lost to follow-up, whereas 14 patients completed the treatment. A sustained virological response (SVR) was obtained in all but one patient carrying NS3-RAS V170I who later relapsed. GT 4a is the most common subtype in this small cohort of Saudi Arabia patients infected with hepatitis C infection. Natural RASs were observed in about one-third of patients, but only one of them showed a treatment failure.

Severe systemic thrombosis in a young COVID-19 patient with a rare homozygous prothrombin G20210A mutation.

COVID-19 patients may experience a hypercoagulable condition, leading to thrombotic events. We describe a patient with COVID-19, carrying a rare homozygous mutation of the prothrombin gene, who developed a severe systemic vein thrombosis. In COVID-19 patients with hypercoagulability disorders the most common inherited and acquired risk factors should be investigated.

Low Prevalence of Antibodies to SARS-CoV-2 and Undetectable Viral Load in Seropositive Blood Donors from South-Eastern Italy.

Recently, a significant cluster of pneumonia caused by a novel betacoronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) was described initially in China and then spread throughout the world. Like other coronaviridae, the viral transmission occurs mainly through droplets. In addition, the virus has been detected in different clinical specimens, suggesting a potential transmission by other routes, including blood transfusion. However, the potential risk of transmission of SARS-CoV-2 via blood products is still unclear. The aim of our study was to investigate the prevalence of antibodies against SARS-CoV-2 among blood donors from South-Eastern Italy. Moreover, in the seropositive donors, we searched for the presence of the virus in nasopharyngeal swabs and in plasma samples. Overall, 1,797 blood donors from the Apulia region were tested for anti-SARS-CoV-2 antibodies, using a commercially available assay. Only 18/1,797 donors (1.0%) tested positive for anti-SARS-CoV-2 antibodies; in none of them SARS-CoV-2 viral RNA was detected in nasopharyngeal swabs and in plasma samples. Our results indicate that most of the blood donors in Apulia remained uninfected during this wave of the pandemic; further, none had detectable virus both in nasopharyngeal swabs and in blood samples. The risk to carry and transmit the virus by healthy and asymptomatic blood donors is probably very low.

Resistance Associated Mutations in HCV Patients Failing DAA Treatment.

Currently, treatment of chronic hepatitis C is based on a combination of direct-acting antiviral agents (DAAs) which achieve HCV clearance in more than 95% of patients. Despite this high rate of cure, treatment failures can occur in about 3-5% of treated patients. Resistance associated substitutions (RAS) are commonly detected after virological failure, although their role in real-life DAA failures is still debated. This study aimed to evaluate in real-life DAA-failing patients the prevalence of clinically relevant RASs for the different DAA classes and to identify possible predictors. Fifty consecutive HCV-infected patients who experienced a virological failure to a DAA-containing regimen were included in the study. Direct sequencing of HCV regions involved in DAA resistance (NS3, NS5A and NS5B) was performed with Sanger-based homemade protocols. The presence of mutations in the NS3 and NS5A regions was statistically associated with regimens containing protease inhibitors (p<0.0032) and NS5A inhibitors (p<0.0006), respectively. On the contrary, for the NS5B region, the known mutations associated with the NS5B RNA polymerase inhibitors were detected in treated HCV patients, although there was no statistical significance (p>0.5). A significant correlation was found between the presence of RASs and advanced fibrosis/cirrhosis, but not with age, sex and viral load. Our study demonstrates a high frequency of RASs in patients with DAA failure, thus highlighting the usefulness of genotypic tests in this setting. The identification of RASs may guide the choice of the most appropriate drugs for HCV re-treatment.

Results from a survey in healthy blood donors in South Eastern Italy indicate that we are far away from herd immunity to SARS-CoV-2.

Here we present results from a survey on anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence in healthy blood donors from a low incidence coronavirus disease 2019 area (Apulia region, South Eastern Italy). Among 904 subjects tested, only in nine cases (0.99%) antibodies against SARS-CoV-2 were demonstrated. All the nine seropositive patients were negative for the research of viral RNA by reverse transcription polymerase chain reaction in nasopharyngeal swabs. These data, along with those recently reported from other countries, clearly show that we are very far from herd immunity and that the containment measures are at the moment the only realistic instrument we have to slow the spread of the pandemic.

Preliminary Data From the Study of Coagulative Profile of HIV Infected Individuals Suggest a Role For Point Mutations in the Gene in Protein S Deficiency in Individuals Undergoing Highly Antiretroviral Therapy.

BACKGROUND: HIV infection is a known prothrombotic condition but factors involved are still controversial. A role for antiretrovirals, especially protease inhibitors, was advocated. OBJECTIVES: The study aimed to analyze the levels of anticoagulant proteins in virally suppressed HIV-infected subjects treated with different anti-retroviral regimens. MATERIALS AND METHODS: Forty-four patients were included in the study. C and PS, D-Dimers and Fibrinogen levels were determined as well as APC-resistance. PROS1 gene was sequenced in a group of patient. RESULTS: Twelve of the 44 subjects (27%) showed reduced levels of PS, while lower levels of PC were found only in 2 patients (4,5%). No difference in the mean values of PC and PS was found stratifying the study population by antiretroviral regimen administrated (p>0.05).Three patients had higher levels of D-Dimer concentrations and in two of these patients, an association between higher D-Dimer values and lower levels of PS was observed; but however no correlation was found by statistical analysis.PROS1 gene analysis was performed in 26 of the 44 HIV-1 patients and the subjects with low levels of PS had mutation in the fifteen exon of PROS 1 gene. While among individuals with normal levels, this mutation was observed only in 8/18 (44%) of the cases (p=0,0072). CONCLUSION: The majority of patients with low PS levels also had mutations in the fifteen exon of PROS 1 gene. Genetic determinants, deserving further investigations, rather than antiretrovirals might cause PS deficiency in HIV-1 positive patients.

Correlation between knowledge on transmission and prevention of HIV/STI and proficiency in condom use among male migrants from Africa and Middle East evaluated by a Condom Use Skills score using a wooden penile model.

BACKGROUND: Migrants in Italy are prevalently young adults, with a higher risk of sexual transmitted infections (STI) and HIV infection. Promoting consistent as well as correct use of condoms could reduce failure rate due to their improper use. The aim of our study was to evaluate Condom Use Skills among a migrant population recently landed in Italy, hosted in a government center for asylum seekers. METHODS: The study sample was composed of 80 male migrants. Sanitary trained interviewers submitted a questionnaire to participants to investigate age, provenience, marital status, educational level and knowledge about transmission and prevention of HIV/STI. Then, we assessed participants' level of condom use skill with the Condom Use Skills (CUS) measure by using a wooden penile model. The interviewer filled in a checklist and assigned 1 point for correct demonstration of each behavior that may prevent condom failure during sex. RESULTS: Participants' median age was 26 years and the sample was composed of 54 migrants from sub-Saharan Africa and 26 from Middle East. Most of them were married, with a lower middle level of education, up to 8 or 5 years. Half of the sample achieved the highest score in the questionnaire and our CUS showed a large number of people with middle high score classes. The Spearman's rho was 0.30, therefore answers to the questionnaire and CUS score appeared correlated (p < 0.05). In the multivariate model, to have a higher CUS score resulted to be associated to be older than 26 years (p < 0.05), with a higher level of education (p = 0.001), and a higher score in the questionnaire (p < 0.05). There were no significant differences in the level of CUS between single or married men and between African and Middle Asian migrants of the sample. CONCLUSIONS: Our study shows that educational level influences the quality of knowledge and awareness about STI/AIDS and contribute to correct condom use. Since the half of participants had a low educational level and linguistic problems, the risk of missing campaigns messages or misunderstanding informative materials increases. Direct observation of condom-application on penile model may offer realistic assessment of application skills in these individuals.

Serum IgG Antibodies from Pregnant Women Reacting to Mimotopes of Simian Virus 40 Large T Antigen, the Viral Oncoprotein.

Simian virus 40 (SV40) large T antigen (LT) coding sequences were revealed in different human samples, whereas SV40 antibodies (Ab) were detected in human sera of cancer patients and healthy individuals, although with a lower prevalence. Previous studies carried out by the neutralization assay gave a SV40 seroprevalence, in the general population, up to 8%, although higher rates, 12%, were detected in kidney transplant children, in a group of HIV-positive patients, and in healthy females. In this study, serum samples from pregnant women, together with those from non-pregnant women, were analyzed to check the prevalence of IgG Ab reacting to SV40 LT antigens. Serum samples were collected from pregnant and non-pregnant women, with the same mean age. Women were in the range of 15-48 years old. Samples were assayed by an indirect ELISA employing specific SV40 LT mimotopes as antigens, whereas functional analysis was performed by neutralization of the viral infectivity in cell cultures. As a control, sera were analyzed for Ab against BK polyomavirus (BKPyV), which is a human polyomavirus homologous to SV40. Statistical analyses employed chi-square with Yates' correction, and Student's t tests. Indirect ELISAs indicated that pregnant women tested SV40 LT-positive with a prevalence of 17% (23/134), whereas non-pregnant women had a prevalence of 20% (36/180) (P > 0.05). Ab against BKPyV were detected with a prevalence of 80% in pregnant women and with a prevalence of 78% in non-pregnant women. These data indicate that SV40 infects at a low prevalence pregnant women. We may speculate that SV40, or a close human polyomavirus still undetected, could be transmitted from mother to fetus.