Molecular detection of monkeypox and related viruses: challenges and opportunities.

The recent widespread emergence of monkeypox (mpox), a rare and endemic zoonotic disease by monkeypox virus (MPXV), has made global headlines. While transmissibility (R0 ≈ 0.58) and fatality rate (0-3%) are low, as it causes prolonged morbidity, the World Health Organization has declared monkeypox as a public health emergency of international concern. Thus, effective containment and disease management require quick and efficient detection of MPXV. In this bioinformatic overview, we summarize the numerous molecular tests available for MPXV, and discuss the diversity of genes and primers used in the polymerase chain reaction-based detection. Over 90 primer/probe sets are used for the detection of poxviruses. While hemagglutinin and A-type inclusion protein are the most common target genes, tumor necrosis factor receptor and complement binding protein genes are frequently used for distinguishing Clade I and Clade II of MPXV. Problems and possibilities in the detection of MPXV have been discussed.

High HBV-DNA serum levels are associated with type 2 diabetes in adults with positive HBsAg: An observational study.

Background: The prevalence of diabetes is higher in hepatitis B virus (HBV)-infected population. We aimed to examine the relationship between different serum HBV-DNA levels and type 2 diabetes in adults with positive HBV surface antigen (HBsAg). Methods: We conducted cross-sectional analyses of data obtaining from the Clinical Database System of Wuhan Union Hospital. Diabetes was defined by self-report of type 2 diabetes, fasting plasma glucose (FPG) ≥7mmol/L, or glycated hemoglobin (HbA1c) ≥6.5%. Binary logistic regression analyses were performed to investigate the factors associated with diabetes. Results: Among 12,527 HBsAg-positive adults, 2,144 (17.1%) were diabetic. Patients with serum HBV-DNA <100, 100-2000, 2000-20000 and ≥20000 IU/mL accounted for 42.2% (N=5,285), 22.6% (N=2,826), 13.3% (N=1,665) and 22.0% (N=2,751), respectively. The risk of type 2 diabetes, FPG ≥7mmol/L and HbA1c ≥6.5% in individuals with highly elevated serum HBV-DNA level (≥20000 IU/mL) were 1.38 (95% confidence interval [CI]: 1.16 to 1.65), 1.40 (95% CI: 1.16 to 1.68) and 1.78 (95% CI: 1.31 to 2.42) times relative to those with negative or lowly elevated serum HBV-DNA (<100 IU/mL). However, the analyses showed no association of moderately (2000-20000 IU/mL) to slightly (100-2000 IU/mL) raised serum HBV-DNA levels with type 2 diabetes (OR=0.88, P=0.221; OR=1.08, P=0.323), FPG ≥7mmol/L (OR=1.00, P=0.993; OR=1.11, P=0.250) and HbA1c ≥6.5% (OR=1.24, P=0.239; OR=1.17, P=0.300). Conclusion: In HBsAg-positive adults, highly elevated level rather than moderately to slightly raised levels of serum HBV-DNA is independently associated with an increased risk of type 2 diabetes.

Rapid quantification assay of hepatitis B virus DNA in human serum and plasma by Fully Automated Genetic Analyzer µTASWako g1.

Real-time monitoring of serum hepatitis B virus (HBV) levels is essential for the management of patients with chronic HBV infection in clinical practice, including monitoring the resistance of anti-HBV nucleotide analog or the detection of HBV reactivation. In this context, serum HBV deoxyribonucleic acid (DNA) quantification should be rapidly measured. A rapid HBV DNA quantification assay was established on the Fully Automated Genetic Analyzer, µTASWako g1. The assay performs automated sample preparation and DNA extraction, followed by the amplification and detection of quantitative polymerase chain reaction (PCR) combined with capillary electrophoresis (qPCR-CE) on integrated microfluidic chip. This study aimed to evaluate the analytical and clinical performance of HBV DNA assay on the µTASWako g1 platform in human serum and EDTA-plasma. The HBV DNA assay has a linear quantitative range from 20 to 108 IU/mL of HBV DNA with standard deviation (SD) of ≤0.14 log10 IU/mL. The limits of detection of the assay were 4.18 for the serum and 4.35 for EDTA-plasma. The HBV assay demonstrated the equivalent performance in both human serum and EDTA-plasma matrices. The HBV genotypes A to H were detected with an accuracy of ±0.34 log10 IU/mL. In quantification range, the HBV DNA assay was correlated with Roche cobas AmpliPrep/cobas TaqMan Ver2.0 (CAP/CTM v2) (r = 0.964). The mean difference (µTASWako g1-CAP/CTM v2) of the reported HBV DNA was -0.01 log10 IU/mL. Overall, the sensitivity, accuracy, and precision of the µTASWako g1 HBV assay were comparable to the existing commercial HBV DNA assay, and the assay can be completed within 110 min. This evaluation suggests that the HBV DNA assay on the µTASWako g1 is potentially applied for alternative method of the HBV viral load test, in particular with the advantage of the HBV DNA result availability within 2 h, improving the HBV infection management.

TaME-seq2: tagmentation-assisted multiplex PCR enrichment sequencing for viral genomic profiling.

BACKGROUND: Previously developed TaME-seq method for deep sequencing of HPV, allowed simultaneous identification of the human papillomavirus (HPV) DNA consensus sequence, low-frequency variable sites, and chromosomal integration events. The method has been successfully validated and applied to the study of five carcinogenic high-risk (HR) HPV types (HPV16, 18, 31, 33, and 45). Here, we present TaME-seq2 with an updated laboratory workflow and bioinformatics pipeline. The HR-HPV type repertoire was expanded with HPV51, 52, and 59. As a proof-of-concept, TaME-seq2 was applied on SARS-CoV-2 positive samples showing the method's flexibility to a broader range of viruses, both DNA and RNA. RESULTS: Compared to TaME-seq version 1, the bioinformatics pipeline of TaME-seq2 is approximately 40× faster. In total, 23 HPV-positive samples and seven SARS-CoV-2 clinical samples passed the threshold of 300× mean depth and were submitted to further analysis. The mean number of variable sites per 1 kb was ~ 1.5× higher in SARS-CoV-2 than in HPV-positive samples. Reproducibility and repeatability of the method were tested on a subset of samples. A viral integration breakpoint followed by a partial genomic deletion was found in within-run replicates of HPV59-positive sample. Identified viral consensus sequence in two separate runs was > 99.9% identical between replicates, differing by a couple of nucleotides identified in only one of the replicates. Conversely, the number of identical minor nucleotide variants (MNVs) differed greatly between replicates, probably caused by PCR-introduced bias. The total number of detected MNVs, calculated gene variability and mutational signature analysis, were unaffected by the sequencing run. CONCLUSION: TaME-seq2 proved well suited for consensus sequence identification, and the detection of low-frequency viral genome variation and viral-chromosomal integrations. The repertoire of TaME-seq2 now encompasses seven HR-HPV types. Our goal is to further include all HR-HPV types in the TaME-seq2 repertoire. Moreover, with a minor modification of previously developed primers, the same method was successfully applied for the analysis of SARS-CoV-2 positive samples, implying the ease of adapting TaME-seq2 to other viruses.

Comparison of the AmpFire and MA-6000 polymerase chain reaction platforms for high-risk human papillomavirus testing in cervical precancer screening.

High-risk human papillomavirus (hr-HPV) testing for primary cervical precancer screening offers an opportunity to improve screening in low-middle income countries (LMICs). This study aimed to compare the analytic performances of the AmpFire and MA-6000 platforms for hr-HPV DNA testing in three groups of women screened for hr-HPV types in Ghana: group 1 with 33 GeneXpert-archived ThinPrep/liquid-based samples subjected to both tests, group 2 with 50 AmpFire-archived dry brush samples subjected to MA-6000 testing, and group 3 involving 143 cotton swab samples simultaneously subjected to both tests without archiving. The overall agreement rates were 73 %, 92 %, and 84 %, for groups 1-3, respectively, and 84 % (95 % CI, 78.6-88.6) for the entire group. Neither AmpFire nor MA-6000 was more likely to test hr-HPV positive in all three groups and the combined group. Group 1 showed fair agreement without statistical significance (κ = 0.224, 95 % CI, -0.118 to 0.565), while group 3 showed significant moderate agreement (κ = 0.591, 95% CI, 0.442-0.741). Group 2 showed an almost perfect significant level of agreement (κ = 0.802; 95 % CI, 0.616-0.987). Thus, both platforms showed statistically significant moderate to near-perfect agreement for detecting hr-HPV in cervicovaginal samples, with variation according to archiving conditions and duration between sample collection and retesting. For LMICs using these platforms for COVID-19 testing, as the COVID-19 pandemic subsides, the platforms can become available for running other tests such as hr-HPV DNA testing for cervical precancer screening.

Torque teno virus (TTV): A gentle spy virus of immune status, predictive marker of seroconversion to COVID-19 vaccine in kidney and lung transplant recipients.

To date, no comprehensive marker to monitor the immune status of patients is available. Given that Torque teno virus (TTV), a known human virome component, has previously been identified as a marker of immunocompetence, it was retrospectively investigated whether TTV viral load may also represent a marker of ability to develop antibody in response to COVID-19-BNT162B2 vaccine in solid organ transplant recipients (SOT). Specifically, 273 samples from 146 kidney and 26 lung transplant recipients after successive doses of vaccine were analyzed. An inverse correlation was observed within the TTV copy number and anti-Spike IgG antibody titer with a progressive decrease in viremia the further away from the transplant date. Analyzing the data obtained after the second dose, a significant difference in TTV copy number between responsive and nonresponsive patients was observed, considering a 5 log10 TTV copies/mL threshold to discriminate between the two groups. Moreover, for 86 patients followed in their response to the second and third vaccination doses a 6 log10 TTV copies/mL threshold was used to predict responsivity to the booster dose. Although further investigation is necessary, possibly extending the analysis to other patient categories, this study suggests that TTV can be used as a good marker of vaccine response in transplant patients.

PddCas: A Polydisperse Droplet Digital CRISPR/Cas-Based Assay for the Rapid and Ultrasensitive Amplification-Free Detection of Viral DNA/RNA.

Clustered regularly interspaced short palindromic repeats (CRISPR)-based assays have been an emerging diagnostic technology for pathogen diagnosis. In this work, we developed a polydisperse droplet digital CRISPR-Cas-based assay (PddCas) for the rapid and ultrasensitive amplification-free detection of viral DNA/RNA with minimum instruments. LbaCas12a and LbuCas13a were used for the direct detection of viral DNA and RNA, respectively. The reaction mixtures were partitioned with a common vortex mixer to generate picoliter-scale polydisperse droplets in several seconds. The limit of detection (LoD) for the target DNA and RNA is approximately 100 aM and 10 aM, respectively, which is about 3 × 104-105 fold more sensitive than corresponding bulk CRISPR assays. We applied the PddCas to successfully detect severe acute respiratory syndrome coronavirus (SARS-CoV-2) and human papillomavirus type 18 (HPV 18) in clinical samples. For the 23 HPV 18-suspected cervical epithelial cell samples and 32 nasopharyngeal swabs for SARS-CoV-2, 100% sensitivity and 100% specificity were demonstrated. The dual-gene virus detection with PddCas was also established and verified. Therefore, PddCas has potential for point-of-care application and is envisioned to be readily deployed for frequent testing as part of an integrated public health surveillance program.

Utility of Epstein-Barr Virus DNA in Nasopharynx Swabs as a Reflex Test to Triage Seropositive Individuals in Nasopharyngeal Carcinoma Screening Programs.

BACKGROUND: Epstein-Barr virus (EBV) DNA detection in the nasopharynx is considered a biomarker for nasopharyngeal carcinoma (NPC). We evaluated its performance as a reflex test to triage EBV seropositives within an NPC screening program in China. METHODS: The study population was embedded within an ongoing NPC screening trial and included 1111 participants who screened positive for anti-EBV VCA (antibodies against EBV capsid antigens)/EBNA1 (EBV nuclear antigen1)-IgA antibodies (of 18 237 screened). Nasopharynx swabs were collected/tested for EBNA1 gene EBV DNA load. We evaluated performance of EBV DNA in the nasopharynx swab as a reflex test to triage EBV serological high-risk (those referred to endoscopy/MRI) and medium-risk (those referred to accelerated screening) individuals. RESULTS: By the end of 2019, we detected 20 NPC cases from 317 serological high-risk individuals and 4 NPC cases from 794 medium-risk individuals. When used to triage serological high-risk individuals, nasopharynx swab EBV DNA was detected in 19/20 cases (positivity rate among cases: 95.0%; 95% CI, 75.1%-99.9%), with a referral rate of 63.4% (201/317, 95% CI, 57.8%-68.7%) and NPC detection rate among positives of 9.5% (19/201, 95% CI, 5.8%-14.4%). The performance of an algorithm that combined serology with triage of serology high-risk individuals using EBV DNA testing yielded a sensitivity of 72.4% (95% CI, 3.0%-81.4%) and specificity of 97.6% (95% CI, 97.2%-97.9%). When used to triage EBV serological medium-risk individuals, the positivity rate among cases was 75.0% (95% CI, 19.4%-99.4%), with a referral rate of 61.8% (95% CI, 58.4%-65.2%) and NPC detection rate among positives of 0.6% (95% CI, 0.1%-1.8%). CONCLUSIONS: Nasopharynx swab EBV DNA showed promise as a reflex test to triage serology high-risk individuals, reducing referral by ca. 40% with little reduction in sensitivity compared to a serology-only screening program.

Recent Development in Plasmonic Nanobiosensors for Viral DNA/RNA Biomarkers.

Recently, due to the coronavirus pandemic, the need for early diagnosis of infectious diseases, including viruses, is emerging. Though early diagnosis is essential to prevent infection and progression to severe illness, there are few technologies that accurately measure low concentrations of biomarkers. Plasmonic nanomaterials are attracting materials that can effectively amplify various signals, including fluorescence, Raman, and other optical and electromagnetic output. In this review, we introduce recently developed plasmonic nanobiosensors for measuring viral DNA/RNA as potential biomarkers of viral diseases. In addition, we discuss the future perspective of plasmonic nanobiosensors for DNA/RNA detection. This review is expected to help the early diagnosis and pathological interpretation of viruses and other diseases.

Detection of Torquetenovirus and Redondovirus DNA in Saliva Samples from SARS-CoV-2-Positive and -Negative Subjects.

OBJECTIVES: Torquetenovirus (TTV) and Redondovirus (ReDoV) are the most prevalent viruses found in the human respiratory virome in viral metagenomics studies. A large-scale epidemiological study was performed to investigate their prevalence and loads in saliva samples according to SARS-CoV-2 status. METHODS: Saliva samples from 448 individuals (73% SARS-CoV-2 negative and 27% SARS-CoV-2 positive) aged 23-88 years were tested. SARS-CoV-2 and TTV were determined in saliva by specific qualitative and quantitative real-time PCRs, respectively. A sub-cohort of 377 subjects was additionally tested for the presence and load of ReDoV in saliva, and a different sub-cohort of 120 subjects for which paired saliva and plasma samples were available was tested for TTV and ReDoV viremia at the same timepoints as saliva. RESULTS: TTV in saliva was 72% prevalent in the entire cohort, at a mean DNA load of 4.6 log copies/mL, with no difference regardless of SARS-CoV-2 status. ReDoV was found in saliva from 61% of the entire cohort and was more prevalent in the SARS-CoV-2-negative subgroup (65% vs. 52%, respectively). In saliva, the total mean load of ReDoV was very similar to the one of TTV, with a value of 4.4 log copies/mL. The mean viral loads in subjects infected with a single virus, namely, those infected with TTV or ReDoV alone, was lower than in dually infected samples, and Tukey's multiple-comparison test showed that ReDoV single-infected samples resulted in the only true outlier (p = 0.004). Differently from TTV, ReDoV was not detected in any blood samples. CONCLUSIONS: This study establishes the prevalence and mean value of TTV and ReDoV in saliva samples and demonstrates the existence of differences between these two components of the human virome.

Treating Hepatitis B Virus in Times of COVID-19: The Case for Clinical Pharmacogenomics Research in Tenofovir-Induced Kidney Toxicity.

The current pandemic has markedly shifted the focus of the global research and development ecosystem toward infectious agents such as SARS-CoV-2, the causative agent for COVID-19. A case in point is the chronic liver disease associated with hepatitis B virus (HBV) infection that continues to be a leading cause of severe liver disease and death globally. The burden of HBV infection is highest in the World Health Organization designated western Pacific and Africa regions. Tenofovir disoproxil fumarate (TDF) is a nucleoside analogue used in treatment of HBV infection but carries a potential for kidney toxicity. TDF is not metabolized by the cytochrome P450 enzymes and, therefore, its clearance in the proximal tubule of the renal nephron is controlled mostly by membrane transport proteins. Clinical pharmacogenomics of TDF with a focus on drug transporters, discussed in this perspective article, offers a timely example where resource-limited countries and regions of the world with high prevalence of HBV can strengthen the collective efforts to fight both COVID-19 and liver diseases impacting public health. We argue that precision/personalized medicine is invaluable to guide this line of research inquiry. In all, our experience in Ghana tells us that it is important not to forget the burden of chronic diseases while advancing research on infectious diseases such as COVID-19. For the long game with COVID-19, we need to address the public health burden of infectious agents and chronic diseases in tandem.

New vector and vaccine platforms: mRNA, DNA, viral vectors.

PURPOSE OF REVIEW: The purpose of this review is to share the excitement of new developments in the field of vaccine vector modalities against infectious diseases. The focus is on HIV-1/AIDS with reference to the most successful as well as currently tested COVID-19 vaccines, and human trials, which best inform iterative vaccine improvements. RECENT FINDINGS: Several genetic subunit vaccines against SARS-CoV-2 demonstrated protection against severe disease, obtained Emergency Use Authorization and scaled their production to billions of doses. Many more are in efficacy evaluation. In contrast, development of HIV-1 vaccines has been extremely difficult. Perseverance of scientists is deepening our understanding of what constitutes immunity against HIV-1 infection and how to achieve protective levels of relevant responses by active immunization, passive administration or a combination of both. Novel platforms led by RNA play a pivotal role. However, a difficult virus may require a complex approach. Proof of concept for HIV-1 prevention and cure might be at reach, and when it arrives, it will be a great and needed encouragement to the field. SUMMARY: Despite the enormous success of drug treatment, vaccines remain the best solution and likely a necessary component of any package that truly ends the AIDS epidemic.

Monkeypox outbreak: Wastewater and environmental surveillance perspective.

Monkeypox disease (MPXD), a viral disease caused by the monkeypox virus (MPXV), is an emerging zoonotic disease endemic in some countries of Central and Western Africa but seldom reported outside the affected region. Since May 2022, MPXD has been reported at least in 74 countries globally, prompting the World Health Organization to declare the MPXD outbreak a Public Health Emergency of International Concern. As of July 24, 2022; 92 % (68/74) of the countries with reported MPXD cases had no historical MPXD case reports. From the One Health perspective, the spread of MPXV in the environment poses a risk not only to humans but also to small mammals and may, ultimately, spread to potent novel host populations. Wastewater-based surveillance (WBS) has been extensively utilized to monitor communicable diseases, particularly during the ongoing COVID-19 pandemic. It helped in monitoring infectious disease caseloads as well as specific viral variants circulating in communities. The detection of MPXV DNA in lesion materials (e.g. skin, vesicle fluid, crusts), skin rashes, and various body fluids, including respiratory and nasal secretions, saliva, urine, feces, and semen of infected individuals, supports the possibility of using WBS as an early proxy for the detection of MPXV infections. WBS of MPXV DNA can be used to monitor MPXV activity/trends in sewerage network areas even before detecting laboratory-confirmed clinical cases within a community. However, several factors affect the detection of MPXV in wastewater including, but not limited to, routes and duration time of virus shedding by infected individuals, infection rates in the relevant affected population, environmental persistence, the processes and analytical sensitivity of the used methods. Further research is needed to identify the key factors that impact the detection of MPXV biomarkers in wastewater and improve the utility of WBS of MPXV as an early warning and monitoring tool for safeguarding human health. In this review, we shortly summarize aspects of the MPXV outbreak relevant to wastewater monitoring and discuss the challenges associated with WBS.

Carbon Nanotube and Its Derived Nanomaterials Based High Performance Biosensing Platform.

After the COVID-19 pandemic, the development of an accurate diagnosis and monitoring of diseases became a more important issue. In order to fabricate high-performance and sensitive biosensors, many researchers and scientists have used many kinds of nanomaterials such as metal nanoparticles (NPs), metal oxide NPs, quantum dots (QDs), and carbon nanomaterials including graphene and carbon nanotubes (CNTs). Among them, CNTs have been considered important biosensing channel candidates due to their excellent physical properties such as high electrical conductivity, strong mechanical properties, plasmonic properties, and so on. Thus, in this review, CNT-based biosensing systems are introduced and various sensing approaches such as electrochemical, optical, and electrical methods are reported. Moreover, such biosensing platforms showed excellent sensitivity and high selectivity against not only viruses but also virus DNA structures. So, based on the amazing potential of CNTs-based biosensing systems, healthcare and public health can be significantly improved.

Understanding the genetics of viral drug resistance by integrating clinical data and mining of the scientific literature.

Drug resistance caused by mutations is a public health threat for existing and emerging viral diseases. A wealth of evidence about these mutations and their clinically associated phenotypes is scattered across the literature, but a comprehensive perspective is usually lacking. This work aimed to produce a clinically relevant view for the case of Hepatitis B virus (HBV) mutations by combining a chronic HBV clinical study with a compendium of genetic mutations systematically gathered from the scientific literature. We enriched clinical mutation data by systematically mining 2,472,725 scientific articles from PubMed Central in order to gather information about the HBV mutational landscape. By performing this analysis, we were able to identify mutational hotspots for each HBV genotype (A-E) and gene (C, X, P, S), as well as the location of disulfide bonds associated with these mutations. Through a modelling study, we also identified a mutation position common in both the clinical data and the literature that is located at the binding pocket for a known anti-HBV drug, namely entecavir. The results of this novel approach show the potential of integrated analyses to assist in the development of new drugs for viral diseases that are more robust to resistance. Such analyses should be of particular interest due to the increasing importance of viral resistance in established and emerging viruses, such as for newly developed drugs against SARS-CoV-2.

Can torque teno virus be a predictor of SARS-CoV-2 disease progression in cancer patients?

INTRODUCTION: Cancer patients with SARS-CoV-2 infection can experience a broad range of clinical manifestations and outcomes. Previous studies have demonstrated an association between torque teno virus (TTV) load and deficiencies of the immune system. The impact of SARS-CoV-2 and TTV viral loads in cancer patients is unknown. METHODS: In this retrospective study, 157 cancer patients and 191 noncancer controls were analysed for SARS-CoV-2 RNA and TTV DNA presence. RESULTS: SARS-CoV-2 RNA was detected in 66.2% of cancer patients and in 68.6% of noncancer control subjects. In SARS-CoV-2-positive patients, TTV was detectable in 79.8% of cancer patients, while in controls, TTV was detected in 71.7% of subjects. No statistically significant correlation was found between TTV and SARS-CoV-2 loads in cancer patients. However, the 100-day survival rate in cancer patients who died from COVID-19 was significantly lower in the TTV-positive group than in the TTV-negative group (P = 0.0475). In the cancer TTV-positive group, those who died also had a higher load of TTV than those who did not die (P = 0.0097). CONCLUSIONS: Our findings indicated that the presence of TTV in nasopharyngeal swabs from cancer patients was related to a higher number of deaths from COVID-19 and to a higher TTV DNA load.

A sample-to-answer, quantitative real-time PCR system with low-cost, gravity-driven microfluidic cartridge for rapid detection of SARS-CoV-2, influenza A/B, and human papillomavirus 16/18.

The pandemic of coronavirus disease 2019 (COVID-19), due to the novel coronavirus (SARS-CoV-2), has created an unprecedented threat to the global health system, especially in resource-limited areas. This challenge shines a spotlight on the urgent need for a point-of-care (POC) quantitative real-time PCR (qPCR) test for sensitive and rapid diagnosis of viral infections. In a POC system, a closed, single-use, microfluidic cartridge is commonly utilized for integration of nucleic acid preparation, PCR amplification and florescence detection. But, most current cartridge systems often involve complicated nucleic acid extraction via active pumping that relies on cumbersome external hardware, causing increases in system complexity and cost. In this work, we demonstrate a gravity-driven cartridge design for an integrated viral RNA/DNA diagnostic test that does not require auxiliary hardware for fluid pumping due to adopted extraction-free amplification. This microfluidic cartridge only contains two reaction chambers for nucleic acid lysis and amplification respectively, enabling a fast qPCR test in less than 30 min. This gravity-driven pumping strategy can help simplify and minimize the microfluidic cartridge, thus enabling high-throughput (up to 12 test cartridges per test) molecular detection via a small cartridge readout system. Thus, this work addresses the scalability limitation of POC molecular testing and can be run in any settings. We verified the analytical sensitivity and specificity of the cartridge testing for respiratory pathogens and sexually transmitted diseases using SARS-CoV-2, influenza A/B RNA samples, and human papillomavirus 16/18 DNA samples. Our cartridge system exhibited a comparable detection performance to the current gold standard qPCR instrument ABI 7500. Moreover, our system showed very high diagnostic accuracy for viral RNA/DNA detection that was well validated by ROC curve analysis. The sample-to-answer molecular testing system reported in this work has the advantages of simplicity, rapidity, and low cost, making it highly promising for prevention and control of infectious diseases in poor-resource areas.

When 3D genome technology meets viral infection, including SARS-CoV-2.

Mammalian chromosomes undergo varying degrees of compression to form three-dimensional genome structures. These three-dimensional structures undergo dynamic and precise chromatin interactions to achieve precise spatial and temporal regulation of gene expression. Most eukaryotic DNA viruses can invade their genomes into the nucleus. However, it is still poorly understood how the viral genome is precisely positioned after entering the host cell nucleus to find the most suitable location and whether it can specifically interact with the host genome to hijack the host transcriptional factories or even integrate into the host genome to complete its transcription and replication rapidly. Chromosome conformation capture technology can reveal long-range chromatin interactions between different chromosomal sites in the nucleus, potentially providing a reference for viral DNA-host chromatin interactions. This review summarized the research progress on the three-dimensional interaction between virus and host genome and the impact of virus integration into the host genome on gene transcription regulation, aiming to provide new insights into chromatin interaction and viral gene transcription regulation, laying the foundation for the treatment of infectious diseases.

Metagenomic Next-Generation Sequencing Reveals the Profile of Viral Infections in Kidney Transplant Recipients During the COVID-19 Pandemic.

Background: To study the clinical application of metagenomic next-generation sequencing (mNGS) in the detection of viral infections in kidney transplant recipients (KTRs) during the COVID-19 pandemic. Methods: Using mNGS technology, 50 human fluid samples of KTRs were detected, including 20 bronchoalveolar lavage fluid (BALF) samples, 21 urine samples and 9 blood samples. The detected nucleic acid sequences were compared and analyzed with the existing viral nucleic acid sequences in the database, and the virus infection spectrum of KTRs was drawn. Results: The viral nucleic acids of 15 types of viruses were detected in 96.00% (48/50) of the samples, of which 11 types of viruses were in BALF (95.00%, 19/20), and the dominant viruses were torque teno virus (TTV) (65.00%; 13/20), cytomegalovirus (CMV) (45.00%; 9/20) and human alphaherpesvirus 1 (25.00%; 5/20). 12 viruses (95.24%, 20/21) were detected in the urine, and the dominant viruses were TTV (52.38%; 11/21), JC polyomavirus (52.38%; 11/21), BK polyomavirus (42.86%; 9/21), CMV (33.33%; 7/21) and human betaherpesvirus 6B (28.57%; 6/21). 7 viruses were detected in the blood (100.00%, 9/9), and the dominant virus was TTV (100.00%; 9/9). Four rare viruses were detected in BALF and urine, including WU polyomavirus, primate bocaparvovirus 1, simian virus 12, and volepox virus. Further analysis showed that TTV infection with high reads indicated a higher risk of acute rejection (P < 0.05). Conclusions: mNGS detection reveals the rich virus spectrum of infected KTRs, and improves the detection rate of rare viruses. TTV may be a new biomarker for predicting rejection.

Torque teno virus DNA load as a predictive marker of antibody response to a three-dose regimen of COVID-19 mRNA-based vaccine in lung transplant recipients.

BACKGROUND: Previous studies have reported that lung transplant recipients (LTR) develop a poor response to two doses of COVID-19 vaccine, but data regarding the third dose are lacking. We investigated the antibody response after three doses of mRNA vaccine in LTR and its predictive factors. METHODS: A total of 136 LTR, including 10 LTR previously infected and 126 COVID-19-naive LTR, were followed during and after three doses of mRNA vaccine. We retrospectively measured anti-receptor-binding domain (RBD) IgG response and neutralizing antibodies. In a posthoc analysis, we used a multivariate logistic regression model to assess the association between vaccine response and patient characteristics, including viral DNA load (VL) of the ubiquitous Torque teno virus (TTV) (optimal cut-off set by ROC curve analysis), which reflects the overall immunosuppression. RESULTS: After 3 doses, 47/126 (37.3%) COVID-19-naive LTR had positive anti-RBD IgG (responders) and 14/126 (11.1%) had antibody titers above 264 Binding Antibody Units/mL. None neutralized the omicron variant versus 7 of the 10 previously infected LTR. Nonresponse was associated with TTV VL ≥6.2 log10 copies/mL before vaccination (Odds Ratio (OR) = 17.87, 95% confidence interval (CI95) = 3.02-105.72), mycophenolate treatment (OR = 4.73, CI95 = 1.46-15.34) and BNT162b2 (n = 34; vs mRNA-1273, n = 101) vaccine (OR = 6.72, CI95 = 1.75-25.92). In second dose non-responders, TTV VL ≥6.2 or <3.2 log10 copies/mL before the third dose was associated with low (0/19) and high (9/10) rates of seroconversion. CONCLUSION: COVID-19-naive LTR respond poorly to three doses of mRNA vaccine, especially those with high TTV VL. Future studies could further evaluate this biomarker as a guide for vaccine strategies.