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Although rhinoviruses play a major role in exacerbations of childhood asthma, the presence of rhinovirus (RV) RNA in plasma, referred to as viremia, has been investigated in a few studies. The aim of the study was to investigate the presence of rhinovirus viremia at the time of asthma exacerbation and to describe the molecular characteristics of rhinoviruses associated with viremia. We conducted an observational, prospective, multicenter study in eight pediatric hospitals (VIRASTHMA2). Preschool-aged recurrent wheezers (1-5 years) hospitalized for a severe exacerbation were included. Reverse-transcription polymerase chain reaction (RT-PCR) and molecular typing for RV/enteroviruses (EV) were performed on nasal swabs and plasma. Plasma specimens were available for 105 children with positive RT-PCR for RV/EV in respiratory specimens. Thirty-six (34.3%) had positive viremia. In plasma, 28 (82.4%) of the typable specimens were RV-C, five (14.7%) were EV-D68, and one was RV-A (2.9%). In all cases, the RV/EV type was identical in the plasma and respiratory specimens. In conclusion, RV/EV viremia is frequent in severe exacerbations of preschool recurrent wheezers, particularly in RV-C infections.
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Asthme , Infections à Picornaviridae , Rhinovirus , Virémie , Humains , Virémie/virologie , Enfant d'âge préscolaire , Rhinovirus/génétique , Rhinovirus/isolement et purification , Rhinovirus/classification , Asthme/virologie , Mâle , Femelle , Études prospectives , Infections à Picornaviridae/virologie , Nourrisson , ARN viral/génétique , RT-PCR , Plasma sanguin/virologieRÉSUMÉ
BACKGROUND: The prognosis of immunocompromised individuals with COVID-19 remains a significant concern. Information regarding the clinical and virological characteristics of immunocompromised patients infected with SARS-CoV-2 during the Omicron variant period is limited. METHODS: Medical records of patients admitted to our hospital with COVID-19 during the Omicron (BA.1-5) epidemic were retrospectively reviewed. Clinical, virological (nasopharyngeal swabs and blood), and serological data were compared between immunocompromised patients receiving immunosuppressive medications (calcineurin inhibitors, mycophenolate mofetil, or steroids) and control patients not receiving immunosuppressive medications. RESULTS: Twenty-eight immunocompromised patients (25 transplant recipients) and 26 control patients were included. Fourteen of the immunocompromised patients (50%) received monoclonal antibodies. The immunocompromised group included 15 mild/moderate (53.6%), 10 severe (35.7%), and three critical (10.7%) disease severities. The mortality rate due to COVID-19 during hospitalization was 3.6% (1/28) in the immunocompromised group, with no difference between the two groups. Three cases of re-exacerbation after discharge occurred in the immunocompromised group and none in the control group. Linear regression based on nasopharyngeal real-time-PCR cycle threshold (Ct) values according to the time since symptom onset showed markedly slower viral clearance in the immunocompromised group than in the control group (Pslope = 0.078). In the immunocompromised group, patients who received monoclonal antibodies showed faster viral clearance than those who did not receive monoclonal antibodies. The convalescent anti-spike IgG titers were comparable to those in the control group in patients who received monoclonal antibodies and significantly lower than those in the control patients in patients who did not receive monoclonal antibodies (P < 0.001). The prevalence of viremia at onset was significantly higher in the immunocompromised group than in the control group (35.7%, [10/28] vs. 11.5%, [3/26]; P = 0.003). All three patients with critical disease severity in the immunocompromised group exhibited viremia, one of whom died. All three patients with viremia in the control group were critical, of whom two died. CONCLUSIONS: Immunocompromised individuals receiving immunosuppressive medications are more likely to show delayed post-infection SARS-CoV-2 viral clearance and the development of viremia, potentially resulting in worsening severity and outcomes, especially in viremic patients, even during the Omicron epidemic.
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COVID-19 , Sujet immunodéprimé , Immunosuppresseurs , SARS-CoV-2 , Humains , COVID-19/immunologie , COVID-19/virologie , COVID-19/épidémiologie , SARS-CoV-2/immunologie , SARS-CoV-2/génétique , Mâle , Femelle , Adulte d'âge moyen , Études rétrospectives , Immunosuppresseurs/usage thérapeutique , Immunosuppresseurs/effets indésirables , Adulte , Sujet âgéRÉSUMÉ
Background: Chronic hepatitis B (CHB) presents a global health challenge due to its potential to cause severe liver conditions such as hepatocellular carcinoma (HCC) and cirrhosis. Prior research has established a correlation between CHB infection with low-level viremia (LLV) and liver disease progression, such as increased HCC incidence. This study aims to investigate whether LLV during treatment with nucleos(t)ide analogs (NAs) contributes to the accelerated progression of liver fibrosis (LF). Methods: This retrospective cohort study at Jinhua Central Hospital focused on CHB patients undergone NA monotherapy for over 96 weeks. Patients were categorized into maintained virological response (MVR) and LLV groups based on hepatitis B virus (HBV) DNA levels. The study assessed LF using various markers and methods, including chitinase 3-like 1 protein (CHI3L1), aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) score, and transient elastography. Results: Analysis was conducted on 92 CHB patients, categorized into LLV (n=42) and MVR (n=50) groups, following the exclusion of 101 patients for various reasons. Significant findings included lower baseline HBV DNA in MVR (<20 IU/mL) compared to LLV (67.8 IU/mL, P<0.001) and different AST/ALT ratios (LLV: 1.1, MVR: 1.36, P=0.011). LF was assessed using CHI3L1, FIB-4, and APRI, with LLV showing a higher baseline CHI3L1 (LLV:83.3 ng/mL vs MVR: 54.5 ng/mL, P=0.016) and scores compared to MVR, indicative of fibrosis. CHI3L1 levels in LLV were higher at baseline and weeks 48, 72, and 96 than MVR, with significance at baseline (P=0.038) and week 48 (P=0.034). Liver stiffness measurement (LSM) showed a time-dependent decline in both groups but no significant intergroup differences. Conclusion: Non-invasive monitoring of CHB patients who have received treatment indicates that LLV contributes to the progression of LF, necessitating proactive adjustment of antiviral treatment strategies.
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Hemophagocytic lymphohistiocytosis (HLH) is an aggressive syndrome of excessive immune activation. It usually occurs in children, mainly during the first year of life. Primary hemophagocytic lymphohistiocytosis is more common and usually occurs in immunocompromised patients. Secondary hemophagocytic lymphohistiocytosis, on the other hand, is less common, especially in immunocompetent patients. Here, we intend to present a case of a 55-year-old male patient who had no known immune deficiency, presented with epistaxis, and was found to have Epstein-Barr virus (EBV)-induced hemophagocytic lymphohistiocytosis.
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As use of human immunodeficiency virus (HIV) integrase strand transfer inhibitors (INSTI) increases and formulations are being developed for maintenance therapies and chemoprophylaxis, assessing virus suppression under INSTI-based regimens in prevention-relevant biologic compartments, such as the male genital tract, is timely. We used cell-source marker virion immunocapture to examine amplification of particle RNA then assessed the phylogenetic relatedness of seminal and blood viral sequences from men with HIV who were prescribed INSTI-based regimens. Seminal plasma immunocaptures yielded amplifiable virion RNA from 13 of 24 (54%) men, and the sequences were primarily associated with markers indicative of macrophage and resident dendritic cell sources. Genetic distances were greatest (>2%) between seminal virions and circulating proviruses, pointing to ongoing low-level expression from tissue-resident cells. While the low levels in semen predict an improbable likelihood of transmission, viruses with large genetic distances are expressed under potent INSTI therapy and have implications for determining epidemiologic linkages if adherence is suboptimal.
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Infections à VIH , Inhibiteurs de l'intégrase du VIH , Sperme , Sperme/virologie , Humains , Mâle , Infections à VIH/traitement médicamenteux , Infections à VIH/virologie , Inhibiteurs de l'intégrase du VIH/pharmacologie , Inhibiteurs de l'intégrase du VIH/usage thérapeutique , Adulte , Phylogenèse , ARN viral/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/effets des médicaments et des substances chimiques , Virion/métabolisme , Adulte d'âge moyenRÉSUMÉ
Background: Dengue virus (DENV) infection is an important public health problem and causes significant morbidity and mortality. DENV typically causes a febrile illness that ranges from mild asymptomatic infection to fatal dengue hemorrhagic fever (DHF) and/or dengue shock syndrome (DSS). Early prediction of severe dengue disease is of utmost importance for providing prompt monitoring and treatment. The search for an ideal biomarker (host or viral factors) for early prediction of severe dengue remains elusive. Aim: To standardize a real time qRT-PCR for quantifying dengue viremia in serum samples and evaluate the kinetics of dengue viremia and its significance in disease severity. Results: In this ambispective study of 126 laboratory confirmed dengue patients, 72 were primary infections and 54 were secondary infections. The most common serotype was serotype 1 (n = 37) followed by serotype 2 (n = 34). According to WHO 1997 dengue case classification, 111 patients were cases of dengue fever (DF), 13 from DHF and 02 from DSS. Day 3 viremia levels were significantly elevated in severe dengue patients (DHF/DSS) as compared to that of DF (p < 0.05). However, no such association was found between viremia levels and serotype or immune status. Conclusion: Dengue viremia has a significant association with disease severity and day 3 viremia levels may be used as a predictor for dengue disease severity.
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BACKGROUND: Spring viremia of carp virus (SVCV) infects a wide range of fish species and causes high mortality rates in aquaculture. This viral infection is characterized by seasonal outbreaks that are temperature-dependent. However, the specific mechanism behind temperature-dependent SVCV infectivity and pathogenicity remains unclear. Given the high sensitivity of the composition of intestinal microbiota to temperature changes, it would be interesting to investigate if the intestinal microbiota of fish could play a role in modulating the infectivity of SVCV at different temperatures. RESULTS: Our study found that significantly higher infectivity and pathogenicity of SVCV infection in zebrafish occurred at relatively lower temperature. Comparative analysis of the intestinal microbiota in zebrafish exposed to high- and low-temperature conditions revealed that temperature influenced the abundance and diversity of the intestinal microbiota in zebrafish. A significantly higher abundance of Parabacteroides distasonis and its metabolite secondary bile acid (deoxycholic acid, DCA) was detected in the intestine of zebrafish exposed to high temperature. Both colonization of Parabacteroides distasonis and feeding of DCA to zebrafish at low temperature significantly reduced the mortality caused by SVCV. An in vitro assay demonstrated that DCA could inhibit the assembly and release of SVCV. Notably, DCA also showed an inhibitory effect on the infectious hematopoietic necrosis virus, another Rhabdoviridae member known to be more infectious at low temperature. CONCLUSIONS: This study provides evidence that temperature can be an important factor to influence the composition of intestinal microbiota in zebrafish, consequently impacting the infectivity and pathogenicity of SVCV. The findings highlight the enrichment of Parabacteroides distasonis and its derivative, DCA, in the intestines of zebrafish raised at high temperature, and they possess an important role in preventing the infection of SVCV and other Rhabdoviridae members in host fish. Video Abstract.
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Bacteroidetes , Maladies des poissons , Microbiome gastro-intestinal , Infections à Rhabdoviridae , Rhabdoviridae , Température , Danio zébré , Animaux , Maladies des poissons/microbiologie , Maladies des poissons/virologie , Infections à Rhabdoviridae/virologie , Rhabdoviridae/physiologie , Rhabdoviridae/pathogénicité , Bacteroidetes/pathogénicité , Eau , Virus de la nécrose hématopoïétique infectieuse/pathogénicitéRÉSUMÉ
Background: Viremia is a critical factor in understanding the pathogenesis of dengue infection, but limited data exist on viremia kinetics. This study aimed to investigate the kinetics of viremia and its effects on subsequent platelet count, severe dengue, and plasma leakage. Methods: We pooled data from three studies conducted in Vietnam between 2000 and 2016, involving 2340 dengue patients with daily viremia measurements and platelet counts after symptom onset. Viremia kinetics were assessed using a random effects model that accounted for left-censored data. The effects of viremia on subsequent platelet count and clinical outcomes were examined using a landmark approach with a random effects model and logistic regression model with generalized estimating equations, respectively. The rate of viremia decline was derived from the model of viremia kinetics. Its effect on the clinical outcomes was assessed by logistic regression models. Results: Viremia levels rapidly decreased following symptom onset, with variations observed depending on the infecting serotype. DENV-1 exhibited the highest mean viremia levels during the first 5-6 days, while DENV-4 demonstrated the shortest clearance time. Higher viremia levels were associated with decreased subsequent platelet counts from day 6 onwards. Elevated viremia levels on each illness day increased the risk of developing severe dengue and plasma leakage. However, the effect size decreased with later illness days. A more rapid decline in viremia is associated with a reduced risk of the clinical outcomes. Conclusions: This study provides comprehensive insights into viremia kinetics and its effect on subsequent platelet count and clinical outcomes in dengue patients. Our findings underscore the importance of measuring viremia levels during the early febrile phase for dengue studies and support the use of viremia kinetics as outcome for phase-2 dengue therapeutic trials. Funding: Wellcome Trust and European Union Seventh Framework Programme.
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Dengue , Virémie , Humains , Vietnam/épidémiologie , Virémie/sang , Numération des plaquettes , Dengue/sang , Dengue/épidémiologie , Mâle , Femelle , Adulte , Cinétique , Adulte d'âge moyen , Virus de la dengue , Jeune adulte , AdolescentRÉSUMÉ
Low-level viremia (LLV) ranging from 50 to 1,000 copies/ml is common in most HIV-1-infected patients receiving antiretroviral therapy (ART). However, the source of LLV and the impact of LLV on the HIV-1 reservoir during ART remain uncertain. We hypothesized that LLV may arise from the HIV reservoir and its occurrence affect the composition of the reservoir after LLV episodes. Accordingly, we investigated the genetic linkage of sequences obtained from plasma at LLV and pre-ART time points and from peripheral blood mononuclear cells (PBMCs) at pre-ART, pre-LLV, LLV, and post-LLV time points. We found that LLV sequences were populated with a predominant viral quasispecies that accounted for 67.29%â¼100% of all sequences. Two episodes of LLV in subject 1, spaced 6 months apart, appeared to have originated from the stochastic reactivation of latently HIV-1-infected cells. Moreover, 3.77% of pre-ART plasma sequences were identical to 67.29% of LLV-3 plasma sequences in subject 1, suggesting that LLV may have arisen from a subset of cells that were infected before ART was initiated. No direct evidence of sequence linkage was found between LLV viruses and circulating cellular reservoirs in all subjects. The reservoir size, diversity, and divergence of the PBMC DNA did not differ significantly between the pre- and post-LLV sampling points (P > 0.05), but the composition of viral reservoir quasispecies shifted markedly before and after LLV episodes. Indeed, subjects with LLV had a higher total PBMC DNA level, greater viral diversity, a lower proportion of variants with identical sequences detected at two or more time points, and a shorter variant duration during ART compared with subjects without LLV. Overall, our findings suggested that LLV viruses may stem from an unidentified source other than circulating cellular reservoirs. LLV episodes may introduce great complexity into the HIV reservoir, which brings challenges to the development of treatment strategies.
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The immune system of bony fish closely resembles that of mammals, comprising both specific (adaptive) and non-specific (innate) components. Notably, the mucosa-associated lymphoid tissue (MALT) serves as the first line of defense within the non-specific immune system, playing a critical role in protecting these aquatic organisms against invading pathogens. MALT encompasses a network of immune cells strategically distributed throughout the gills and intestines, forming an integral part of the mucosal barrier that interfaces directly with the surrounding aquatic environment. Spring Viremia of Carp Virusï¼SVCVï¼, a highly pathogenic agent causing substantial harm to common carp populations, has been designated as a Class 2 animal disease by the Ministry of Agriculture and Rural Affairs of China. Utilizing a comprehensive array of research techniques, including Hematoxylin and Eosin (HE)ãAlcian Blue Periodic Acid-Schiff (AB-PAS)ãtranscriptome analysis for global gene expression profiling and Reverse Transcription-Polymerase Chain Reaction (RT-qPCR), this study uncovered several key findings: SVCV is capable of compromising the mucosal architecture in the gill and intestinal tissues of carp, and stimulate the proliferation of mucous cells both in gill and intestinal tissues. Critically, the study revealed that SVCV's invasion elicits a robust response from the carp's mucosal immune system, demonstrating the organism's capacity to resist SVCV invasion despite the challenges posed by the pathogen.
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Carpes (poisson) , Maladies des poissons , Analyse de profil d'expression de gènes , Branchies , Intestins , Infections à Rhabdoviridae , Rhabdoviridae , Animaux , Branchies/immunologie , Branchies/virologie , Rhabdoviridae/physiologie , Maladies des poissons/immunologie , Maladies des poissons/virologie , Carpes (poisson)/immunologie , Carpes (poisson)/génétique , Analyse de profil d'expression de gènes/médecine vétérinaire , Infections à Rhabdoviridae/immunologie , Infections à Rhabdoviridae/médecine vétérinaire , Infections à Rhabdoviridae/virologie , Intestins/immunologie , Intestins/virologie , Immunité innée/génétique , Transcriptome/immunologie , Immunité muqueuseRÉSUMÉ
Background Chikungunya is a mosquito-borne re-emerging disease that has caused a significant number of outbreaks recently in diverse geographic settings across the globe. It leads to severe debilitating illness in a significant proportion of persons who are infected. Measures to limit the impact produced by recurrent outbreaks of the disease are limited and there is an urgent clinical need for early identification of those predisposed to develop severe disease. A comprehensive understanding regarding the proportion of individuals predisposed to developing severe disease is lacking as its correlation with detectable viremia is hinted at by some studies. In this context, we hypothesized that detectable viremia reflected in the diagnostic RT-PCR assay could be significantly associated with the development of severe disease in Chikungunya among those diagnosed on the basis of seroconversion. Our study aims to confirm the same in relation to disease severity among the suspected patients of Chikungunya in the setting of a tertiary care center. Methods In a prospective observational study at a tertiary care center, a total number of 1021 Chikungunya suspects presenting within seven days of illness were screened with Chikungunya Virus IgM ELISA from 2021 to 2023. Those having positive IgM results were further tested with RT-PCR in a blinded manner. According to the information entered into the predesigned form and the hospital follow-up/discharge data, the cases where symptoms like fever and joint pain persisted beyond two weeks were classified as severe versus those resolving within two weeks as mild. The patients in each group were compared for their clinical symptoms and association with the disease severity with detectable viremia (RT-PCR positivity). Results We identified a total of 178 (17.4%) lab-confirmed Chikungunya IgM-positive cases amongst the recruited patients. Here a total of 31 (18.9%) cases could be classified as severe and 133 (74.7%) as mild illness, the remaining 14 patients were excluded from analysis due to insufficient clinical data. Severe illness was significantly higher in elderly individuals belonging to more than 60 years (p = 0.01). Viremia was detected in 16 (9%), those with detectable viremia had higher odds (OR = 4.1) of manifesting as severe disease. Among the severe cases, the proportion of cases with RT-PCR positivity (8, 25.8%) at presentation was significantly higher (P = 0.01) versus those who presented with mild disease (7, 5.5%). Conclusion Our study reveals a correlation between detectable viremia in Chikungunya virus (CHIKV) patients and an increased risk of manifesting into a severe disease, where severe cases exhibited a significantly higher proportion of viremia, indicated by RT-PCR positivity. This study hints at the presence of viremia, joint symptoms, and elderly age as potentially useful clinical predictors of disease outcomes, these may serve as indicators for closer monitoring among individuals seeking medical attention due to Chikungunya infection. However, we need to validate these findings in future longitudinal studies incorporating multiple, time-bound follow-up data on clinical outcomes, viral titers, and its long-term complications.
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Canine distemper virus (CDV) is a highly contagious pathogen within the morbillivirus genus infecting a wide range of different carnivore species. The virus shares most biological features with other closely related morbilliviruses, including clinical signs, tissue tropism, and replication cycle in the respective host organisms.In the laboratory environment, experimental infections of ferrets with CDV were established as a potent surrogate model for the analysis of several aspects of the biology of the human morbillivirus, measles virus (MeV). The animals are naturally susceptible to CDV and display severe clinical signs resembling the disease seen in patients infected with MeV. As seen with MeV, CDV infects immune cells and is thus associated with a strong transient immunosuppression. Here we describe several methods to evaluate viral load and parameters of immunosuppression in blood-circulating immune cells isolated from CDV-infected animals.
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Modèles animaux de maladie humaine , Virus de la maladie de Carré , Maladie de Carré , Furets , Charge virale , Animaux , Furets/virologie , Virus de la maladie de Carré/pathogénicité , Maladie de Carré/virologie , Maladie de Carré/anatomopathologieRÉSUMÉ
Hepatitis B virus (HBV) infection is a dynamic disease where patients progress through several stages defined by HBV e-antigen (HBeAg) status, HBV-DNA levels and transaminase elevations, with antiviral therapy indicated only in specific stages. However, some patients cannot be classified into one of the stages and are said to fall into an 'indeterminate phase' or 'grey zone'. Exact definitions of the indeterminate phase vary from guideline to guideline as a result of different cut-off values for biomarker measurements. Data suggest that as many as 50% of HBV patients may be in an indeterminate phase and may not rapidly transition out of this phase. Clinical data that suggest these patients are at increased risk of hepatocellular carcinoma (HCC) are complemented by molecular evidence of integrations of HBV-DNA into the host genome, chromosomal translocations and immune activation despite liver enzymes that may suggest lack of inflammation. Antiviral therapy reduces these hepatocarcinogenic mechanisms and is reflected in a reduction of fibrosis and HCC risk. We review key data on patients in the indeterminate phase, with emphasis on HCC as an outcome. We take a holistic approach and link new biological data with clinical observations as well as examine the potential role of antiviral therapy in reducing HCC risk among patients in the indeterminate phase. With the availability of safe and effective oral antivirals, consideration must be given as to how much residual risk of HCC should be tolerated among patients in the indeterminate phase.
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The SARS-CoV-2 (COVID-19) pandemic has impacted the care of people living with HIV (PLWH). This study aims to characterize the impact of the pandemic on the length of HIV treatment gap lengths and viral loads among people living with HIV (PLWH) in British Columbia (BC), Canada, with a focus on Downtown Eastside (DTES), which is one of the most impoverished neighbourhoods in Canada. We analyzed data from the HIV/AIDS Drug Treatment Program from January 2019 to February 2022. The study had three phases: Pre-COVID, Early-COVID, and Late-COVID. We compared results for individuals residing in DTES, those not residing in DTES, and those with no fixed address. Treatment gap lengths and viral loads were analyzed using a zero-inflated negative binomial model and a two-part model, respectively, adjusting for demographic factors. Among the 8982 individuals, 93% were non-DTES residents, 6% were DTES residents, and 1% had no fixed address during each phase. DTES residents were more likely to be female, with Indigenous Ancestry, and have a history of injection drug use. Initially, the mean number of viral load measurements decreased for all PLWH during the Early-COVID, then remained constant. Treatment gap lengths increased for all three groups during Early-COVID. However, by Late-COVID, those with no fixed address approached pre-COVID levels, while the other two groups did not reach Early-COVID levels. Viral loads improved across each phase from Pre- to Early- to Late-COVID among people residing and not residing in DTES, while those with no fixed address experienced consistently worsening levels. Despite pandemic disruptions, both DTES and non-DTES areas enhanced HIV control, whereas individuals with no fixed address encountered challenges. This study offers insights into healthcare system preparedness for delivering HIV care during future pandemics, emphasizing community-driven interventions with a particular consideration of housing stability.
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COVID-19 , Infections à VIH , Charge virale , Humains , Colombie-Britannique/épidémiologie , Femelle , Mâle , Infections à VIH/traitement médicamenteux , Infections à VIH/épidémiologie , COVID-19/épidémiologie , Adulte , Adulte d'âge moyen , Virémie/épidémiologie , Virémie/traitement médicamenteux , SARS-CoV-2 , PandémiesRÉSUMÉ
We evaluated subsequent virologic outcomes in individuals experiencing low-level virem ia (LLV) on dolutegravir (DTG)-based first-line antiretroviral therapy (ART) in Botswana. We used a national dataset from 50,742 adults who initiated on DTG-based first-line ART from June 2016-December 2022. Individuals with at least two viral load (VL) measurements post three months on DTG-based first-line ART were evaluated for first and subsequent episodes of LLV (VL:51-999 copies/mL). LLV was sub-categorized as low-LLV (51-200 copies/mL), medium-LLV (201-400 copies/mL) and high-LLV (401-999 copies/mL). The study outcome was virologic failure (VF) (VL ≥ 1000 copies/mL): virologic non-suppression defined as single-VF and confirmed-VF defined as two-consecutive VF measurements after an initial VL < 1000 copies/mL. Cox regression analysis identified predictive factors of subsequent VF. The prevalence of LLV was only statistically different at timepoints >6-12 (2.8%) and >12-24 (3.9%) (p-value < 0.01). LLV was strongly associated with both virologic non-suppression (adjusted hazards ratio [aHR] = 2.6; 95% CI: 2.2-3.3, p-value ≤ 0.001) and confirmed VF (aHR = 2.5; 95% CI: 2.4-2.7, p-value ≤ 0.001) compared to initially virally suppressed PLWH. High-LLV (HR = 3.3; 95% CI: 2.9-3.6) and persistent-LLV (HR = 6.6; 95% CI: 4.9-8.9) were associated with an increased hazard for virologic non-suppression than low-LLV and a single-LLV episode, respectively. In a national cohort of PLWH on DTG-based first-line ART, LLV > 400 copies/mL and persistent-LLV had a stronger association with VF. Frequent VL testing and adherence support are warranted for individuals with VL > 50 copies/mL.
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Infections à VIH , Composés hétérocycliques 3 noyaux , Oxazines , Pipérazines , Pyridones , Charge virale , Virémie , Humains , Infections à VIH/traitement médicamenteux , Infections à VIH/virologie , Pyridones/usage thérapeutique , Composés hétérocycliques 3 noyaux/usage thérapeutique , Mâle , Botswana , Oxazines/usage thérapeutique , Femelle , Adulte , Charge virale/effets des médicaments et des substances chimiques , Pipérazines/usage thérapeutique , Adulte d'âge moyen , Virémie/traitement médicamenteux , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/effets des médicaments et des substances chimiques , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , Échec thérapeutique , Agents antiVIH/usage thérapeutique , Thérapie antirétrovirale hautement active , Inhibiteurs de l'intégrase du VIH/usage thérapeutiqueRÉSUMÉ
Stimulator of interferon genes (STING), as an imperative adaptor protein in innate immune, responds to nucleic acid from invading pathogens to build antiviral responses in host cells. Aberrant activation of STING may trigger tissue damage and autoimmune diseases. Given the decisive role in initiating innate immune response, the activity of STING is intricately governed by several posttranslational modifications, including phosphorylation and ubiquitination. Here, we cloned and characterized a novel RNF122 homolog from common carp (named CcRNF122L). Expression analysis disclosed that the expression of CcRNF122L is up-regulated under spring viremia of carp virus (SVCV) stimulation in vivo and in vitro. Overexpression of CcRNF122L hampers SVCV- or poly(I:C)-mediated the expression of IFN-1 and ISGs in a dose-dependent way. Mechanistically, CcRNF122L interacts with STING and promotes the polyubiquitylation of STING. This polyubiquitylation event inhibits the aggregation of STING and the subsequent recruitment of TBK1 and IRF3 to the signaling complex. Additionally, the deletion of the TM domain abolishes the negative regulatory function of CcRNF122L. Collectively, our discoveries unveil a mechanism that governs the STING function and the precise adjustment of the innate immune response in teleost.
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Carpes (poisson) , Protéines de poisson , Immunité innée , Protéines membranaires , Rhabdoviridae , Animaux , Carpes (poisson)/immunologie , Carpes (poisson)/génétique , Carpes (poisson)/virologie , Protéines membranaires/génétique , Protéines membranaires/immunologie , Protéines membranaires/métabolisme , Rhabdoviridae/physiologie , Protéines de poisson/génétique , Protéines de poisson/immunologie , Protéines de poisson/métabolisme , Ubiquitination , Ubiquitin-protein ligases/génétique , Ubiquitin-protein ligases/métabolisme , Maladies des poissons/immunologie , Maladies des poissons/virologie , Infections à Rhabdoviridae/immunologie , Transduction du signalRÉSUMÉ
BACKGROUND AND STUDY AIMS: The present study was undertaken to design a new machine learning (ML) model that can predict the presence of viremia in hepatitis C virus (HCV) antibody (anti-HCV) seropositive cases. PATIENTS AND METHODS: This retrospective study was conducted between January 2012-January 2022 with 812 patients who were referred for anti-HCV positivity and were examined for HCV ribonucleic acid (HCV RNA). Models were constructed with 11 features with a predictor (presence and absence of viremia) to predict HCV viremia. To build an optimal model, this current study also examined and compared the three classifier data mining approaches: RF, SVM and XGBoost. RESULTS: The highest performance was achieved with XGBoost (90%), which was followed by RF (89%), SVM Linear (85%) and SVM Radial (83%) algorithms, respectively. The four most important key features contributing to the models were: alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (ALB) and anti-HCV levels, respectively, while "ALB" was replaced by the "AGE" only in the XGBoost model. CONCLUSION: This study has shown that XGBoost and RF based ML models, incorporating anti-HCV levels and routine laboratory tests (ALT, AST, ALB), and age are capable of providing HCV viremia diagnosis with 90% and 89% accuracy, respectively. These findings highlight the potential of ML models in the early diagnosis of HCV viremia, which may be helpful in optimizing HCV elimination programs.
Sujet(s)
Alanine transaminase , Aspartate aminotransferases , Anticorps de l'hépatite C , Hépatite C , Apprentissage machine , ARN viral , Virémie , Humains , Virémie/diagnostic , Études rétrospectives , Anticorps de l'hépatite C/sang , Femelle , Mâle , Alanine transaminase/sang , Aspartate aminotransferases/sang , ARN viral/sang , Adulte d'âge moyen , Hépatite C/diagnostic , Algorithmes , Hepacivirus/immunologie , Hepacivirus/génétique , Adulte , Sérumalbumine , Valeur prédictive des testsRÉSUMÉ
Tripartite motif (TRIM) proteins are involved in different cellular functions, including regulating virus infection. In teleosts, two orthologous genes of mammalian TRIM2 are identified. However, the functions and molecular mechanisms of piscine TRIM2 remain unclear. Here, we show that trim2b-knockout zebrafish are more susceptible to spring viremia of carp virus (SVCV) infection than wild-type zebrafish. Transcriptomic analysis demonstrates that NOD-like receptor (NLR), but not RIG-I-like receptor (RLR), signaling pathway is significantly enriched in the trim2b-knockout zebrafish. In vitro, overexpression of Trim2b fails to degrade RLRs and those key proteins involved in the RLR signaling pathway but does for negative regulators NLRP12-like proteins. Zebrafish Trim2b degrades NLRP12-like proteins through its NHL_TRIM2_like and IG_FLMN domains in a ubiquitin-proteasome degradation pathway. SVCV-N and SVCV-G proteins are also degraded by NHL_TRIM2_like domains, and the degradation pathway is an autophagy lysosomal pathway. Moreover, zebrafish Trim2b can interfere with the binding between NLRP12-like protein and SVCV viral RNA and can completely block the negative regulation of NLRP12-like protein on SVCV infection. Taken together, our data demonstrate that the mechanism of action of zebrafish trim2b against SVCV infection is through targeting the degradation of host-negative regulators NLRP12-like receptors and viral SVCV-N/SVCV-G genes.IMPORTANCESpring viremia of carp virus (SVCV) is a lethal freshwater pathogen that causes high mortality in cyprinid fish. In the present study, we identified zebrafish trim2b, NLRP12-L1, and NLRP12-L2 as potential pattern recognition receptors (PRRs) for sensing and binding viral RNA. Zebrafish trim2b functions as a positive regulator; however, NLRP12-L1 and NLRP12-L2 function as negative regulators during SVCV infection. Furthermore, we find that zebrafish trim2b decreases host lethality in two manners. First, zebrafish Trim2b promotes protein degradations of negative regulators NLRP12-L1 and NLRP12-L2 by enhancing K48-linked ubiquitination and decreasing K63-linked ubiquitination. Second, zebrafish trim2b targets viral RNAs for degradation. Therefore, this study reveals a special antiviral mechanism in lower vertebrates.
Sujet(s)
Carpes (poisson) , Protéolyse , Récepteurs de reconnaissance de motifs moléculaires , Rhabdoviridae , Protéines à motif tripartite , Protéines virales , Protéines de poisson-zèbre , Danio zébré , Animaux , Carpes (poisson)/virologie , Protéine-58 à domaine DEAD/métabolisme , Maladies des poissons/virologie , Maladies des poissons/métabolisme , Immunité innée , Récepteurs de reconnaissance de motifs moléculaires/métabolisme , Rhabdoviridae/métabolisme , Infections à Rhabdoviridae/métabolisme , Infections à Rhabdoviridae/médecine vétérinaire , Infections à Rhabdoviridae/virologie , Transduction du signal , Protéines à motif tripartite/déficit , Protéines à motif tripartite/génétique , Protéines à motif tripartite/métabolisme , Ubiquitination , Protéines virales/métabolisme , Virémie/médecine vétérinaire , Virémie/virologie , Danio zébré/génétique , Danio zébré/métabolisme , Danio zébré/virologie , Protéines de poisson-zèbre/déficit , Protéines de poisson-zèbre/génétique , Protéines de poisson-zèbre/métabolismeRÉSUMÉ
Polyomaviruses, particularly BK virus, are ubiquitous latent infections that may reactivate with immunosuppression during kidney transplantation, resulting in polyomavirus nephropathy (PVN). The levels of viruria and viremia serve as tools for screening and making a presumptive diagnosis of PVN, respectively, while a definitive diagnosis requires a kidney biopsy. There are histologic classifications of PVN based on the extent of tubular cell viral infection, interstitial fibrosis, and interstitial inflammation. These classifications correlate to some degree with graft function and loss, aiding in determining treatment efficacy and prognostication. PVN has histologic overlap with acute cell-mediated rejection, making the differential diagnosis challenging, although there are suggestive features for these different causes of graft dysfunction. This article reviews the diagnosis, histologic findings, and classifications of PVN, and discusses how to differentiate viral nephropathy from acute rejection.