Reverse Assay Research Articles

Development and evaluation of an antigen targeting lateral flow test for Crimean-Congo Haemorrhagic Fever

Crimean-Congo Haemorrhagic Fever (CCHF) is a viral haemorrhagic fever with a case fatality rate of 5-25% that has been prioritised for research and development by the World Health Organisation. There are no CCHF rapid diagnostic tests (RDTs) commercially available. We describe the development and evaluation of an antigen-targeting lateral flow immunoassay RDT for CCHF. Prospective clinical samples were collected and tested between July and October 2023 in Türkiye. Retrospective stored samples were obtained from the Central Public Health Laboratory, Baghdad, Iraq. The sensitivity and specificity of the CCHF RDT was compared to reverse transcription quantitative polymerase chain reaction assays. On prospective clinical samples in Türkiye, the sensitivity and specificity of the CCHF RDT was 90.4% [95% CI 81.5-95.3%] (n=73) and 96.2% [95% CI 87.0-99.3%] (n=52), respectively with a sensitivity of 92.9% [95% CI 84.3-96.9%] (n=70) in samples with a cycle threshold (Ct) ≤30. On retrospective stored samples in Iraq, sensitivity and specificity of the RDT was 71.7% [95% CI 59.2-81.5%] (n=60) and 92.5% [95% CI 80.1-97.8%] (n=40), respectively with a sensitivity of 82.2% [95% CI 68.7-90.7%] (n=45) in samples of Ct ≤30. The CCHF RDT was an effective rapid diagnostic test in this preliminary clinical evaluation, showing this RDT has the potential diagnostic capability for use at the point-of-care. Definitive evaluation is now required to ensure the RDT meets the regulatory requirements for commercialisation. The Liverpool School of Tropical Medicine, National Institute for Health Research Health Protection Research Unit in Emerging Zoonotic Infections, The Medical Research Council and The Pandemic Institute.

One-Step Multiplex Polymerase Chain Reaction Assay for the Detection of Major Disease-Transmitting Mosquito Vectors in India.

Mosquitoes are important vectors that transmit viral, protozoan, and helminthic diseases across the world. Climate change and unplanned urbanization are accelerating the spread of these diseases. Controlling vector-borne diseases can be performed most effectively through vector control. Inadequate knowledge of vector bionomics is an impediment and can lead to inappropriate vector control efforts. However, the conventional methods of vector identification are based on morphological differences, demand a significant amount of time and specific skills, and are often misleading. An efficient and affordable solution is needed to quickly and accurately identify pooled samples from vast geographical territories. To ensure the correct identification of distorted or pooled samples in India, a set of definitive steps is required, including the construction of unique primers and the standardization of a one-step assay based on the second internal transcribed spacer gene of the ribosomal DNA. We have successfully developed and confirmed a highly efficient one-step multiplex reverse transcriptase polymerase chain reaction assay for the accurate identification of major mosquito vectors, especially in the cases of both the adult and larval forms of Anopheles sp., Aedes sp., and Culex sp. Hence, the specificity, universality, and uniqueness of these primers could serve as a critical tool for the rapid one-step and one-reaction identification of mosquitoes to control mosquito-borne disease outbreaks and public health emergencies.

Polyphyllin VII enhances the sensitivity of endometrial carcinoma cells to medroxyprogesterone acetate through upregulating miR‑33a‑5p expression.

Endometrial carcinoma (EC) often exhibits resistance to hormone therapies, such as medroxyprogesterone acetate (MPA), highlighting the need for novel strategies to enhance therapeutic efficacy. The present study aimed to investigate the effects of polyphyllin VII (PPVII) on the efficacy of MPA in EC, focusing on the regulatory role of microRNA (miR)-33a-5p. Briefly, an MPA-resistant Ishikawa cell line (Ishikawa/MPA-R), maintained with 10 µM MPA, was established and transfected with negative control (NC) and miR-33a-5p inhibitors. Following treatment with PPVII and MPA, the proliferation capacity and apoptosis levels of the Ishikawa and Ishikawa/MPA-R cells were evaluated using reverse transcription-quantitative polymerase chain reaction, MTT assay, clonogenic assay, flow cytometry, western blotting and dual-luciferase assay. Next, the expression levels of miR-33a-5p and F-box and leucine rich repeat protein 16 (FBXL16) were measured, and the regulatory relationship between miR-33a-5p and FBXL16 was analyzed. Significant reductions in cell viability were observed in all groups following treatment with increased concentrations of MPA and PPVII, with the greatest effect observed in the combined MPA + PPVII group (P<0.01). The apoptosis levels of the Ishikawa/MPA-R cells were significantly increased in all drug treatment groups, particularly in the MPA + PPVII group (P<0.05). PPVII treatment significantly increased the expression level of miR-33a-5p in Ishikawa/MPA-R cells (P<0.01). In the PPVII + miR-33a-5p inhibitor group, the Ishikawa/MPA-R cells exhibited an upregulation in the viability (P<0.01), colony formation ability (P<0.01), proportion in the G1 phase (P<0.05) and the protein expression levels of cyclin D1 (P<0.01) and cyclin-dependent kinase 4 (P<0.01), and a reduction in the miR-33a-5p expression (P<0.01), apoptosis levels (P<0.05), proportion in the S (P<0.05) and G2 phases and the levels of Bcl-2-associated X protein (P<0.001). The FBXL16 protein expression in Ishikawa/MPA-R cells was significantly higher compared with Ishikawa cells, and the mRNA and protein expression levels of FBXL16 were markedly elevated in the PPVII + miR-33a-5p inhibitor group compared with the PPVII + NC group (P<0.01). These findings suggested that PPVII upregulated the expression of miR-33a-5p, enhanced the sensitivity of EC cells to MPA and potentially exerted anticancer effects in EC through the synergistic action of the miR-33a-5p/FBXL16 axis in combination with MPA.

Deciphering sepsis: An observational bioinformatic analysis of gene expression in granulocytes from GEO dataset GSE123731.

Sepsis triggers severe inflammatory responses leading to organ dysfunction and demands early diagnostic and therapeutic intervention. This study identifies differentially expressed genes (DEGs) in sepsis patients using the Gene Expression Omnibus database to find potential diagnostic and therapeutic markers. We analyzed the dataset GSE123731 via GEO2R to detect DEGs, constructed protein-protein interaction networks, and performed transcription factor analyses using Cytoscape. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted using R and FunRich software. Key genes were validated by Quantitative Reverse Transcription Polymerase Chain and co-immunoprecipitation assays in granulocytes from sepsis patients. We identified 59 DEGs significantly involved in neutrophil degranulation and immune system activation. Cytokine signaling pathways were highlighted in Kyoto Encyclopedia of Genes and Genomes analysis. Co-immunoprecipitation assays confirmed interactions involving matrix metallopeptidase 8, matrix metallopeptidase 9, and arginase 1, supporting their roles as biomarkers. The identified DEGs and validated interactions reveal crucial molecular mechanisms in sepsis, offering new avenues for diagnostic and therapeutic strategies, potentially enhancing patient outcomes.

Identification of β-globin gene mutations among transfusion-dependent β-thalassemia patients

Abstract BACKGROUND: β-thalassemias are widely distributed in Mediterranean and Middle Eastern countries, including Iraq. There are more than 400 transfusion-dependent β-thalassemia patients registered in the thalassemia center. β-thalassemia is a significant problem in Karbala as well as other regions of Iraq. The detection of the most frequent mutations is significant to the implementation of an effective preventive program in this area because of the significant burden it places on the local health authorities, patients, and their families. OBJECTIVES: To define the most common mutations and their frequencies among patients with transfusion-dependent β-thalassemia and to evaluate the reverse hybridization strip assay method for the detection of β-thalassemia mutations. PATIENTS, MATERIALS AND METHODS: Sixty transfusion-dependent β-thalassemia patients were recruited from the thalassemia center in Karbala. Blood samples were aspirated from each patient just before blood transfusions for CBC, reticulocyte count, DNA extraction, PCR amplification, and identification of the mutations by reverse hybridization technique using the β-Globin strip assay method. RESULTS: A total of 60 patients with 120 chromosomes were studied, searching for the most common mutations causing β-thalassemia. Among the twelve identified mutations, the six most frequent mutations represented 79.16% of all β-globin defects. These mutations were IVSII-1 (30.83%), IVSI-110 (15.83%), Codon 5 (10.83%), Codon 44 (8.33%), IVSI-1 (6.67%), and IVSI-5 (6.67%). The detection rate of the method used in our population was 96.66%. CONCLUSION: The most frequent mutations encountered were IVSII.1 and IVSI-110, while IVS 2.745 was the least common mutant allele. Reverse hybridization strip assay molecular techniques used in the current study provide an extremely quick, precise, and simple to carry out molecular diagnostic technique for the detection of β-thalassemia mutations.

Application and Optimization of Reverse Transcription Loop-Mediated Isothermal Amplification Assay for Rapid SARS-CoV-2 Detection in Humans and Animals

Application and Optimization of Reverse Transcription Loop-Mediated Isothermal Amplification Assay for Rapid SARS-CoV-2 Detection in Humans and Animals

Evaluating A Rapid Molecular Assay In A Mobile Lab For Improved Diagnosis Of Dengue In Bangladesh

ObjectivesDengue emerged as a significant health threat in the endemic regions in recent years. However, inconsistent diagnostic accuracy in sequential dengue infections necessitate improved testing methods to ensure effective management of dengue cases. Here, we evaluated a portable, rapid, and sensitive molecular assay – Reverse Transcriptase Recombinase Polymerase Amplification Assay (RT-RAA) utilizing a mobile suitcase laboratory to detect infections in suspected dengue cases in Bangladesh. Method364 suspected dengue patients were enrolled in the study. Dengue cases were confirmed by a positive result from any of the four tests NS1 RDT, IgM RDT, qRT-PCR and RT-RAA assay. IgG RDT was performed to differentiate between primary and secondary dengue infections. ResultsOf 364 suspected cases, 320 were confirmed dengue cases, with 55.94% classified as primary and 44.06% as secondary infections. Laboratory results showed comparable positivity rates between RT-RAA(78.8%) and NS1 RDT(77.1%) in primary dengue, followed by qRT-PCR(57.5%) and IgM RDT(12.8%). RT-RAA demonstrated superior positivity rates in secondary dengue(76.6%), surpassing RT-PCR(60.3%), NS1 RDT(27%), and IgM RDT (24.8%). Combining RT-RAA with NS1 RDT detected infections in 89.95% primary and 81.56% secondary dengue. ConclusionThe findings suggest complementing RT-RAA to NS1 RDT could significantly improve dengue detection rate, particularly for secondary infections.

Network pharmacology and in vitro experiments reveal the potential therapeutic effects of Scrophularia ningpoensis Hemsl in the treatment of ameloblastoma

PurposeThis study aimed to explore active ingredients in Scrophularia ningpoensis Hemsl (SNH) with potential effects on ameloblastoma (AM) using network pharmacological approach, bioinformatic gene analysis and in vitro cell experiments. MethodsThe active ingredients and their corresponding targets of SNH were identified from the Traditional Chinese Medicine Systems Pharmacology (TCMSP), as well as SwissTargetPrediction. Disease targets of AM were selected from GeneCards and DisGeNET databases. Differentially expressed genes (DEGs) of AM were identified, and Gene Ontology enrichment analysis were performed using the Gene Expression Omnibus (GEO) dataset GSE38494 through bioinformatic analysis. The STRING database platform was utilized to generate a protein–protein interaction network diagram, followed by hub gene analysis using Cytoscape software. AutoDock Vina software was used to perform molecular docking verification of the effects of the active ingredients on potential core targets. Additionally, in vitro experiments including quantitative reverse transcription polymerase chain reaction (RT-qPCR), EdU assay and CCK-8 cell proliferation assay were conducted using AM cell line AM-1 after SNH extract treatment. ResultThe study revealed that SNH contains eight active ingredients and a total of 388 drug targets, including 10 potential core targets in AM. Hub genes identified in the analysis were CCNA2, HRAS, PTGS2, PIK3CB, FGFR1, CASP3, MMP1, SLC2A1, MMP14, and MME. Molecular docking analysis demonstrated strong binding activity between key active ingredients (β-sitosterol, scropolioside A_qt, scropolioside D, scropolioside D_qt, and sugiol) and target genes (CASP3, FGFR1, HRAS, PTGS2, and SLC2A1). Gene Ontology enrichment analysis indicated that SNH exerts its effects on AM through pathways related to cellular response to abiotic stimulus, cellular response to hypoxia, and exopeptidase activity. Immunohistochemical analysis using tissue microarray showed higher expression of MMP14 and PTGS2 in AM compared to dentigerous cyst. Using AM-1 cell line, RT-qPCR results confirmed that SNH suppressed the expression of MMP14 and PTGS2 at mRNA level. Additionally, the EdUassay and CCK-8 assay indicated the inhibitory effect of SNH on the proliferation of AM-1 cells. ConclusionThese findings showed that SNH could suppress expression of MMP14 and PTGS2 and restrain the proliferation of AM. Our study highlights the potential of SNH as a promising therapeutic candidate for AM, which may provide more options for clinical treatment.

Highly Sensitive and Specific Diagnosis of Enterovirus A71 by Reverse Transcription Multiple Cross-Displacement Amplification-Labeled Nanoparticles Biosensor.

Enterovirus A71 (EVA71) is a leading causative agent of hand, foot, and mouth disease, posing a significant threat to the health of young children, particularly in the Asia-Pacific region. Currently, there is no specific antiviral drug for EVA71 infection; therefore, early and rapid diagnosis is critical for disease prevention and control. Here, we report the development of a simple, rapid, and sensitive detection method for EVA71 infection using reverse transcription-multiple cross displacement amplification (RT-MCDA) combined with nanoparticle-based lateral flow biosensors (LFB). In the RT-MCDA system, a set of 10 primers was designed to target the highly conserved region of the VP1 gene of EVA71 and amplify the genes in an isothermal amplification device. The RT-MCDA amplification reaction products could then be identified by visual detection reagent (VDR) and LFB without the need for specialized equipment. The results demonstrated that the optimal reaction condition for the EVA71-RT-MCDA assay was 65℃ for 40 min. The EVA71-RT-MCDA assay could detect as low as 40 copies of plasmid and 50 copies of pseudotyped virus in a reaction. No cross-reaction was found between EVA71 strains and non-EVA71 strains. For 125 clinical anal swab samples, with EVA71-RT-MCDA assay, 30 samples were positive, which was in consistent with the the conventional real-time quantitative reverse transcription polymerase chain reaction assays. The entire procedure, including a 15-min specimen processing step, a 40-min MCDA reaction, and result reporting within 2 min, was completed in less than 60 min. In conclusion, the EVA71-RT-MCDA-LFB assay targeting the VP1 gene is a rapid, highly sensitive, simple, and specific test that could be widely applied in point-of-care settings and basic medical facilities in rural areas.

Key performance evaluation of commercialized multiplex rRT-PCR kits for respiratory viruses: implications for application and optimization.

The complexity and severity of viral respiratory tract infections (RTIs) emphasize the pivotal role of precise diagnosis for viral RTIs in guiding effective public health responses and ensuring appropriate medical interventions, given the substantial population at risk. This study highlights the necessity and importance of evaluating the analytical validity of multiplex real-time reverse transcription polymerase chain reaction assays, offering valuable insights into their optimization and application.

Influence of diverse pH and temperatures on the gene expression of toxin-antitoxin systems in Klebsiella pneumoniae

Background: The type II toxin-antitoxin system consists of tightly linked genetic units that produce a toxin and its specific antitoxin. Under typical circumstances, the antitoxin neutralizes the toxic effects caused by the toxin. However, the toxin-antitoxin systems during stress regulate bacterial growth and persistence by affecting translation or DNA replication. This study aimed to assess how variations in temperature and pH stress influence the regulation of type II toxin-antitoxin gene expression within Klebsiella pneumoniae isolates.Methods: Sixty-five Klebsiella pneumoniae isolates were identified by the VITEK®2 compact system and confirmed identity by Polymerase Chain Reaction assay by amplified rpoB gene (Housekeeping gene). The isolates were subjected to Reverse Transcriptase-polymerase chain Reaction assay to determine the transcriptional variations of the type II toxin-antitoxin system genes at diverse temperature and pH values.Results: The results of the current study demonstrated higher expression levels of the antitoxin hipB gene at (37℃, 30℃, 44℃, pH 7, pH 9), mqsR toxin gene at (37℃, 30℃, pH 7, pH 5, pH 11) and relE toxin gene at (pH 5, pH 11).Conclusion: These findings suggest the possible influence of pH and temperature on toxin-antitoxin systems, which might enhance bacterial antibiotic tolerance and persistence.Keywords: Toxin-antitoxin systems; pH stress; Temperature stress; Klebsiella pneumoniae; Gene expression; Reverse Transcriptase PCR

The Microbial Metabolite Wuyiencin Potential Targets Threonine dehydratase in Didymella segeticola to Achieve Control of Tea Leaf Spot.

Tea leaf spot caused by Didymella segeticola is a disease that has recently been discovered in the tea plantations of Southwest China, and which has a significant negative impact on the yield and quality of tea leaves. Wuyiencin is a nucleotide antimicrobial that is effective against a range of fungal diseases. However, its mode of action is still unclear. The current study found that wuyiencin inhibited the mycelial growth of D. segeticola in vitro. Meanwhile, in vivo experiments confirmed that wuyiencin had a significant curative effect on tea leaf spot. Microscopic observation represented it damaged the organelles and nucleus in fungal cells. Reverse transcription quantitative PCR assays revealed that mycelium treated with wuyiencin at the half-maximal effective concentration (EC50) dosage for 1 hour exhibited 3.23 times lower expression of Threonine dehydratase (Td) gene, which is responsible for producing pyruvate. The wild type (WT) strain had a 1.77-fold higher pyruvate concentration than that in the td mutant (P < 0.05). The td mutant was more sensitive than the WT to wuyiencin treatment, with the EC50 value in the td mutant being 30.01 μg/ml, compared with 82.34 μg/ml in the WT. Molecular docking demonstrated that wuyiencin bound to Td, with a binding energy of -10.47 kcal/mol. Compared with the WT strain, wuyiencin significantly reduced ATP concentration of the td mutant strain at dosages of 80.0 and 160.0 µg/ml. In total, wuyiencin reduced Td activity, inhibited pyruvate production, and decreased ATP content in the phytopathogenic fungus, ultimately disturbing the growth of the mycelium.

Transcriptomic analysis reveals Streptococcus agalactiae activation of oncogenic pathways in cervical adenocarcinoma.

Cervical adenocarcinoma (AC), a subtype of uterine cervical cancer (CC), poses a challenge due to its resistance to therapy and poor prognosis compared with squamous cervical carcinoma. Streptococcus agalactiae [group B Streptococcus (GBS)], a Gram-positive coccus, has been associated with cervical intraepithelial neoplasia in CC. However, the underlying mechanism interaction between GBS and CC, particularly AC, remains elusive. Leveraging The Cancer Genome Atlas public data and time-series transcriptomic data, the present study investigated the interaction between GBS and AC, revealing activation of two pivotal pathways: 'MAPK signaling pathway' and 'mTORC1 signaling'. Western blotting, reverse transcription-quantitative PCR and cell viability assays were performed to validate the activation of these pathways and their role in promoting cancer cell proliferation. Subsequently, the present study evaluated the efficacy of two anticancer drugs targeting these pathways (binimetinib and ridaforolimus) in AC cell treatment. Binimetinib demonstrated a cytostatic effect, while ridaforolimus had a modest impact on HeLa cells after 48 h of treatment, as observed in both cell viability and cytotoxicity assays. The combination of binimetinib and ridaforolimus resulted in a significantly greater cytotoxic effect compared to binimetinib or ridaforolimus monotherapy, although the synergy score indicated an additive effect. In general, the MAPK and mTORC1 signaling pathways were identified as the main pathways associated with GBS and AC cells. The combination of binimetinib and ridaforolimus could be a potential AC treatment.

From the discovery of a novel arepavirus in diseased arecanut palms (Areca catechu L.) in India to the identification of known and novel arepaviruses in bee and plant transcriptomes through data-mining

Arecanut palm is a commercially important plantation crop valued for its nut. In this investigation, we report the discovery of a putative novel arepavirus, named areca palm necrotic ringspot virus 2 (ANRSV2), in necrotic ringspot diseased areca palms in Bantwal, Dakshina Kannada, Karnataka, India through RNA-sequencing and transmission electron microscopy. Further, the presence of ANRSV2 in the diseased samples was confirmed through reverse transcriptase-polymerase chain reaction assays. In addition, by mining public domain transcriptome data for arepaviral sequences, we identified a putative novel arepavirus in Psychotria rubra, a non-palm host. We recovered the genome sequences of the areca palm necrotic ringspot virus in honey bees, tomato, Onobrychis viciifolia, and Rhamnus heterophylla. These findings broaden our comprehension of arepaviral diversity and host range, and suggest an intriguing possibility of pollen-mediated arepaviral transmission that necessitates empirical validation. Further studies are needed to understand the biology of identified putative novel arepaviruses.

B-052 Celiac Disease Risk Assessment of HLA-DQ Typing in IgA Deficient Patients

Abstract Background Celiac disease (CeD) is a chronic autoimmune disorder triggered by the ingestion of gluten in persons with the genetic risk factors human leukocyte antigens (HLA)-DQ2 and DQ8. Diagnostic evaluation of patients with suspected CeD often includes serology tests for tissue transglutaminase (tTG) antibodies. While the presence of HLA-DQ2 or DQ8 is required for the initiation and development of CeD, the genetic risk associated with the various alleles is not equivalent. Previous studies in patients with normal total IgA demonstrated the risk gradients of various HLA-DQ2 and DQ8 heterodimers in CeD. However, the impact of both gene variants in IgA deficient patients has not been investigated. In this study, HLA-DQ2 and HLA-DQ8 as risk factors for tTG-IgG positivity in IgA deficient patients were evaluated. Methods Retrospective data was collected from a cohort of individuals (n=3,515) with IgA concentrations below the age-dependent reference interval with suspicion for CeD who were tested for HLA-DQ genotyping and tTG-IgG (reference interval &amp;lt; 6 U/mL) at Mayo Clinic Laboratories. Total IgA was measured using quantitative nephelometry (Siemens BN™ II System); HLA typing was performed using the reverse SSO DNA typing assay (LABType SSO kits). tTG-IgG was determined by enzyme-linked immunosorbent assay (QUANTA Lite R h-tTG, Werfen Diagnostics) on the Dynex Agility System. The prevalence and frequency distribution of HLA-DQ2 and DQ8 haplotypes were determined and the odds ratio (OR) was calculated to evaluate the risk gradient for tTG-IgG positivity based on different HLA-DQ variants. Results Among IgA deficient patients, 58% (n=2,041) expressed HLA-DQ2 or DQ8 haplotypes. Relative to patients without permissive alleles, patients homozygous for HLA-DQ2.5 exhibited a significantly increased risk for tTG-IgG positivity (OR = 10.98, 95% CI: 6.56-18.18, p &amp;lt; 0.001) while those homozygous for HLA-DQ2.2 and DQ8 did not (DQ2.2/DQ2.2_OR = 0.72, 95% CI: 0.04-3.44, p = 0.75; DQ8/DQ8_OR = 0.96, 95% CI: 0.05-4.64, p = 0.97). Patients heterozygous for HLA-DQ2.5 (DQ2.5/x) displayed a lower odds ratio relative to homozygous patients (OR = 3.31, 95% CI: 2.29-4.82, p &amp;lt; 0.001); however, the risk for tTG-IgG positivity increased in the presence of HLA-DQ2.2 (DQ2.5/DQ2.2_OR = 7.59, 95% CI: 4.48-12.65, p &amp;lt; 0.001) or HLA-DQ8 (DQ2.5/DQ8_OR = 6.26, 95% CI: 3.55-10.73, p &amp;lt; 0.001) alleles. Conversely, in the absence of HLA-DQ2.5, HLA-DQ2.2 heterozygotes (DQ2.2/x_OR = 2.80, 95% CI: 1.77-4.39, p &amp;lt; 0.001) and HLA-DQ8 heterozygotes (DQ8/x_OR = 0.99, 95% CI: 0.52-1.77, p = 0.99) displayed lower correlations with tTG-IgG positivity, suggesting a potential risk elevation for tTG-IgG positivity is associated with the combination of DQ2.5 and DQ2.2 or DQ8. Conclusions Our study indicates the risk gradient of HLA-DQ genes in IgA deficient patients. Overall, compared to patients without HLA-DQ2 or DQ8 haplotypes, the homozygous HLA-DQ2.5 genotype had the highest correlation with tTG-IgG positivity, followed by HLA-DQ2.5/DQ2.2 and HLA-DQ2.5/DQ8 heterodimers. The results suggest that HLA-DQ2.2 or HLA-DQ8 alone does not confer risk, but when in the presence of HLA-DQ2.5 these alleles may increase the risk for tTG-IgG positivity. Results from this study shed light on the risk of CeD in patients with IgA deficiency.

Colorectal Cancer-Derived Exosomes Impair CD4+ T Cell Function and Accelerate Cancer Progression via Macrophage Activation.

Background: Exosomal programmed death ligand 1 (PD-L1), an exosomal membrane protein found in many tumor types, is reckoned to help regulate the immune microenvironment. However, the functions and the mechanisms underlying the exosome-mediated regulation of the immune microenvironment in colorectal cancer (CRC) remain unknown. Methods: Western blotting was used to investigate the levels of exosomal PD-L1 in the peripheral blood of patients with CRC and healthy controls. A CRC mouse model was constructed by administering 10 mg/kg azoxymethane (AOM) and dextrane sodium sulfate (DSS) intraperitoneally. The mice were then administered the control or CRC-derived exosomes to examine the regulatory effect of the exosomes on macrophage infiltration and CRC development. In vitro studies, using a coculture system, and flow cytometry analysis were conducted to examine the relationship between the regulatory effect of CRC-derived exosomes on CD4+ T cells and tumor-associated macrophages. RNA-seq and reverse transcription-quantitative polymerase chain reaction assays were used to investigate the mechanisms underlying the regulatory effect of the CRC-derived exosomes on macrophage proliferation and the regulation of the immune microenvironment during CRC development. Results: In patients with CRC, higher levels of exosomal PD-L1 were associated with a more severe form of disease. The treatment of mice with AOM/DSS-induced CRC with CRC-derived exosomes resulted in high levels of macrophage proliferation, increased PD-L1 levels in macrophages, and accelerated CRC progression. Importantly, analysis of an in vitro coculture system and flow cytometry analysis showed that the CRC-derived exosomes transported PD-L1 into macrophages and impaired CD4+ T cell function. Preliminary data suggest that the NF-κb signaling pathway regulates the function of CRC-derived exosomal PD-L1-dependent macrophages. Conclusion: CRC-derived exosomes induce the proliferation of macrophages and increase their PD-L1 levels. They also impair CD4+ T cell function and promote CRC progression. Our findings reveal a novel exosomal PD-L1-mediated crosstalk between the CRC cells and immune cells in the CRC microenvironment.

Real-time quantitative reverse transcription PCR assay for the detection of Nuomin virus – An emerging tick-borne virus

Nuomin virus (NOMV), an emerging tick-borne virus (TBVs) identified in 2020, has been associated with fever, headache, and potential liver dysfunction in infected individuals. This study presents a novel TaqMan real-time quantitative PCR method designed for the rapid, sensitive, and specific detection of NOMV, facilitating early diagnosis. Utilizing Beacon Designer software 8.0, we optimized the PCR assay including the development of primers and probes to precisely target the conserved region of the NOMV genome, followed by optimization of primer and probe concentrations and annealing temperature. The resulting assay demonstrated robust performance, with standard curve represented by the equation y=−3.29x+39.42, a high correlation coefficient (R2 = 0.995) and an efficiency 99.53 %. Importantly, the method exhibited exceptional specificity, which did not yield cross-reacting signals from other TBVs, including Songling virus (SGLV), Beiji virus (BJNV), tick-borne encephalitis virus (TBEV), Yezo virus (YEZV), Alongshan virus (ALSV), and severe fever with thrombocytopenia syndrome bunyavirus (SFTSV). The assay’s detection limit was remarkably low, reaching 10 copies/μL, representing a 100-fold increase compared to semi-nested RT-PCR. Additionally, it demonstrated excellent repeatability, with coefficients of variation for intra- and inter-group tests consistently below 3 %. Clinical evaluations confirmed the assay’s superior performance, highlighting its high specificity, sensitivity, and reproducibility for NOMV detection. In conclusion, the method developed in this study provides a valuable tool to support timely management of NOMV infections, with significant implications for clinical practice.

Validation of a direct multiplex real-time reverse transcription PCR assay for rapid detection of African swine fever virus using swine field samples in Vietnam

ObjectiveThis study validates a direct multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assay which was previously established for enabling rapid and simultaneous detection of African swine fever (ASF) virus (ASFV) and classical swine fever virus. The assay eliminates the need for viral nucleic acid purification using a buffer system for crude extraction and an impurity-tolerant enzyme. However, the assay had not yet been validated using field samples of ASFV-infected pigs. Therefore, to address this gap, we tested 101 samples collected from pigs in Vietnam during 2018 and 2021 for validation.ResultsThe rRT-PCR assay demonstrated a diagnostic sensitivity of 98.8% and a specificity of 100%. Remarkably, crude samples yielded results comparable to those of purified samples, indicating the feasibility of using crude samples without compromising accuracy in ASFV detection. Our findings emphasize the effectiveness of the rRT-PCR assay for the prompt and accurate diagnosis of both swine fever viruses, which is essential for effective disease prevention and control in swine populations.

Changes in the molecular nodes of the Notch and NRF2 pathways in cervical cancer tissues from the precursor stages to invasive carcinoma.

Cancer is a multifactorial disease characterized by the loss of control in the expression of genes known as cancer driver genes. Cancer driver genes trigger uncontrolled cell replication, which leads to the development of malignant tumors. A cluster of signal transduction pathways that contain cancer driver genes involved in cellular processes, such as cell proliferation, differentiation, apoptosis and dysregulated organ growth, are associated with cancer initiation and progression. In the present study, three signal transduction pathways involved in cervical cancer (CC) development were analyzed: The Hippo pathway (FAT atypical cadherin, yes-associated protein 1, SMAD4 and TEA domain family member 2), the Notch pathway [cellular-MYC, cAMP response element-binding binding protein (CREBBP), E1A-associated cellular p300 transcriptional co-activator protein and F-Box and WD repeat domain containing 7] and the nuclear factor erythroid 2-related factor 2 (NRF2) pathway [NRF2, kelch-like ECH-associated protein 1 (KEAP1), AKT and PIK3-catalytic subunit α]. Tumor samples from patients diagnosed with various stages of CC, including cervical intraepithelial neoplasia (CIN) 1, CIN 2, CIN 3, in situ CC and invasive CC, were analyzed. The mRNA expression levels were analyzed using reverse transcription-quantitative PCR assays, whereas protein expression levels were assessed through immunohistochemical tissue microarrays. High mRNA expression levels of c-MYC and AKT and low expression levels of NRF2 and KEAP1 were associated with a decreased survival time of patients with CC. Additionally, increased expression levels of c-MYC were detected in the invasive CC stage. At the protein level, increased NRF2 expression levels were observed in all five stages of CC samples compared with those in the cancer-free control samples. AKT1 was found to be dysregulated in the CIN 1 and CIN 2 stages, PI3K in the in situ and invasive stages, and CREBBP in the CIN 3 and in situ stages. In summary, the present study demonstrated significant changes in proteins of the Notch and NRF2 pathways in CC. NRF2 was overexpressed in all cervical cancer stages (cervical intraepithelial neoplasia, in situ CC and invasive CC). The present study makes an important contribution to the possible biomarker proteins to be analyzed for the presence of premalignant and malignant lesions in the cervix.

Ruptured Aortic Valve Aneurysm Caused by Infective Endocarditis in a SARS-CoV-2-Positive Autopsy Case.

Aortic valve aneurysm, an extremely rare complication secondary to infective endocarditis (IE), may cause heart failure due to rupture of the aneurysm. Coronavirus disease 2019 (COVID-19) has been reported to cause cardiovascular complications and alter susceptibility to secondary infections such as IE. Herein, we report a case of IE with a fatal outcome caused by rupture of an aortic valve aneurysm in a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive autopsy case. The patient was a 67-year-old male diagnosed with heart failure after presenting with edema and weight gain. He was found dead in bed 2 weeks after initial symptom presentation. Autopsy revealed an aneurysmal sac in the center of the noncoronary cusp of the aortic valve with an opening of approximately 1 cm in the center of the aneurysmal wall. Histologically, aortic valve vegetation, destruction of the aortic valve cusp, rupture of the aneurysmal wall, and an abscess under the aortic intima were observed. Gram staining of the aneurysmal wall showed a gram-positive coccus. The reverse transcription quantitative polymerase chain reaction assay was positive for SARS-CoV-2. Because no defined risk factors for IE other than SARS-CoV-2 infection were observed, the association between IE and COVID-19 was highly likely.