Adenovirus infections [keywords]
- Incidence and etiology of hospitalized acute respiratory infections in the Egyptian Delta. [JOURNAL ARTICLE]
- Influenza Other Respir Viruses 2016 Jul 26.
Acute Respiratory Infections (ARI) are responsible for nearly two million childhood deaths worldwide. A limited number of studies have been published on the epidemiology of viral respiratory pathogens in Egypt.A total of 6113 hospitalized patients >1 month of age with suspected ARI were enrolled between June 23, 2009 and December 31, 2013. Naso-and oropharyngeal specimens were collected and tested for influenza A and B, respiratory syncytial virus, human metapneumovirus, adenovirus, and parainfluenza viruses 1-3. Blood specimens from children 1-11 months were cultured and bacterial growth was identified by polymerase chain reaction. Results from a healthcare utilization survey on the proportion of persons seeking care for ARI was used to calculate adjusted ARI incidence rates in the surveillance population.The proportion of patients with a viral pathogen detected decreased with age from 67% in patients age 1-11 months to 19% in patients ≥65 years of age. Influenza was the dominant viral pathogen detected in patients ≥1 year of age (13.9%). The highest incidence rates for hospitalized ARI were observed in children 1-11 months (1757.9-5537.5/100 000 population) and RSV was the most commonly detected pathogen in this age group.In this study population, influenza is the largest viral contributor to hospitalized ARIs and children 1-11 months of age experience a high rate of ARI hospitalizations. This study highlights a need for surveillance of additional viral pathogens and alternative detection methods for bacterial pathogens, which may reveal a substantial proportion of as yet unidentified etiologies in adults. This article is protected by copyright. All rights reserved.
- [THE APPLICATION OF DOT-TECHNIQUE FOR DETECTING ANTIGENS OF ADENOVIRUS IN CLINICAL SAMPLES]. [English Abstract, Journal Article]
- Klin Lab Diagn 2016 Feb; 61(2):122-5.
The article substantiates possibility of application of point enzyme-linked immunosorbent assay (dot-technique) for detecting viral antigens in samples from patients. To diagnose adenovirus infection conjugate of virus-specific monoclonal antibodies and peroxidase of horse-radish were used The chromatographic rectification of conjugate from free peroxidase permits diminishing background coloring of nitrocellulose membrane and therefore to increase sensitivity. The application of direct conjugates on the basis of virus-specific monoclonal antibodies increases specifcity of dot-technique and significantly shortens time period of analysis. As in case of application of direct conjugates on the basis of polyclonal serum, samples from patients require preliminary processing with detergent for preventing non-specific reactions. The dot-technique demonstrates good coincidence with data of polymerase chain reaction and after clinical trials it can be used in diagnostic of human viral infections.
- Acute viral respiratory infections among children in MERS-endemic Riyadh, Saudi Arabia, 2012-2013. [JOURNAL ARTICLE]
- J Med Virol 2016 Jul 19.
The emergence of the Middle East Respiratory Syndrome (MERS) emergence in Saudi Arabia has intensified focus on Acute Respiratory Infections [ARIs]. This study sought to identify respiratory viruses (RVs) associated with ARIs in children presenting at a tertiary hospital.Children (aged ≤ 13) presenting with ARI between January 2012 and December 2013 tested for 15 RVs using the Seeplex(R) RV15 kit were retrospectively included. Epidemiological data was retrieved from patient records.Of the 2235 children tested, 61.5% were ≤1 year with a male: female ratio of 3:2. Viruses were detected in 1364 (61.02%) children, 233(10.4%) having dual infections: these viruses include respiratory syncytial virus RSV) (24%), human rhinovirus (hRV) (19.7%), adenovirus (5.7%), influenza virus (5.3%) and parainfluenzavirus-3 (4.6%). Children aged 9-11 months were most infected (60.9%). Lower respiratory tract infections (55.4 %) were significantly more than upper respiratory tract infection (45.3 %) (P<0.001). Seasonal variation of RV was directly and inversely proportional to relative humidity and temperature, respectively, for non MERS coronaviruses (NL63, 229E and OC43).The study confirms community-acquired RV associated with ARI in children and suggests modulating roles for abiotic factors in RV epidemiology. However, community-based studies are needed to elucidate how these factors locally influence RV epidemiology. This article is protected by copyright. All rights reserved.
- Occurrence, risk factors and outcome of adenovirus infection in adult recipients of allogeneic hematopoietic stem cell transplantation. [JOURNAL ARTICLE]
- J Clin Virol 2016 Jul 10.:33-40.
Adenovirus (ADV) infections can have a high mortality in immunocompromised patients and are difficult to treat.We retrospectively analyzed occurrence and risk factors of ADV infection in 399 adults with hematological disorders undergoing hematopoietic stem cell transplantation (allo-HSCT), focusing on alternative donor transplantation (ADT) and disseminated disease.ADV infection occurred in 42 patients (10.5%). Disease was localized in 18 and disseminated in 6 patients. ADV infection was observed in 15% after ADT, performed in 29% of all recipients, and was less frequent (6%) in T-cell-replete (TCR) haploidentical transplantation using post-transplantation cyclophosphamide (PTCY) than in other ADT protocols. Lower age, the use of alternative donor grafts and acute graft-versus-host disease (GvHD)≥grade II were risk factors for ADV infection. After failure of standard antiviral treatment, three patients with disseminated ADV disease received one dose of ADV-specific T cells, resulting in virological response in 2/3 patients, clearance of ADV viremia in 2/2 patients, and survival of 1/3 patients; both patients with pneumonia died.ADV infection was of moderate occurrence in our adult recipients of allo-HSCT despite a high proportion of potential high-risk patients receiving ADT. TCR strategies using PTCY might limit ADV complications in haploidentical transplantation. Despite feasible adoptive therapy strategies, outcome of disseminated disease remains dismal.
- Respiratory macrophages regulate CD4 T memory responses to mucosal immunization with recombinant adenovirus-based vaccines. [JOURNAL ARTICLE]
- Cell Immunol 2016 Jul 12.
Respiratory immunization is an attractive way to generate systemic and mucosal protective memory responses that are required for preventing mucosally transmitted infections. However, the molecular and cellular mechanisms for controlling memory T cell responses remain incompletely understood. In this study, we investigated the role of respiratory macrophage (MΦ) in regulating CD4 T cell responses to recombinant adenovirus-based (rAd) vaccines. We demonstrated that rAd intranasal (i.n.) vaccination induced migration and accumulation of respiratory MΦ and circulatory monocytes in the mediastinal lymph nodes and lung parenchyma. Under the influence of respiratory MΦ CD4 T cells exhibited slow proliferation kinetics and an increased tendency of generating central memory, as opposed to effector memory, CD4 T cell responses in vitro and in vivo. Correspondingly, depletion of MΦ using clodronate-containing liposome prior to i.n. immunization significantly enhanced CD4 T cell proliferation and increased the frequency of CD4 memory T cells in the airway lumen, demonstrating that MΦ initially serve as a negative regulator in limiting generation of mucosal tissue-resident memory CD4 T cells. However, clodronate-containing liposome delivery following i.n. immunization markedly reduced the frequencies of memory CD4 T cells in the airway lumen and spleen, indicating that respiratory MΦ and potentially circulating monocytes are critically required for maintaining long-term memory CD4 T cells. Collectively, our data demonstrate that rAd-induced mucosal CD4 T memory responses are regulated by respiratory MΦ and/or monocytes at multiple stages.
- Germinal Center B Cell and T Follicular Helper Cell Responses to Viral Vector and Protein-in-Adjuvant Vaccines. [JOURNAL ARTICLE]
- J Immunol 2016 Jul 13.
There is great interest in the development of Ab-inducing subunit vaccines targeting infections, including HIV, malaria, and Ebola. We previously reported that adenovirus vectored vaccines are potent in priming Ab responses, but uncertainty remains regarding the optimal approach for induction of humoral immune responses. In this study, using OVA as a model Ag, we assessed the magnitude of the primary and anamnestic Ag-specific IgG responses of mice to four clinically relevant vaccine formulations: replication-deficient adenovirus; modified vaccinia Ankara (a poxvirus); protein with alum; and protein in the squalene oil-in-water adjuvant Addavax. We then used flow cytometric assays capable of measuring total and Ag-specific germinal center (GC) B cell and follicular Th cell responses to compare the induction of these responses by the different formulations. We report that adenovirus vectored vaccines induce Ag insert-specific GC B cell and Ab responses of a magnitude comparable to those induced by a potent protein/squalene oil-in-water formulation whereas-despite a robust overall GC response-the insert-specific GC B cell and Ab responses induced by modified vaccinia Ankara were extremely weak. Ag-specific follicular Th cell responses to adenovirus vectored vaccines exceeded those induced by other platforms at day 7 after immunization. We found little evidence that innate immune activation by adenovirus may act as an adjuvant in such a manner that the humoral response to a recombinant protein may be enhanced by coadministering with an adenovirus lacking a transgene of interest. Overall, these studies provide further support for the use of replication-deficient adenoviruses to induce humoral responses.
- Neutrophil infiltration and activation in bronchiolitic airways are independent of viral etiology. [JOURNAL ARTICLE]
- Pediatr Pulmonol 2016 Jul 13.
Hospitalization with bronchiolitis is linked to the development of early childhood chronic wheeze and asthma. Viral etiology and severity of inflammation are potential contributing factors. Previously we observed reduced airway neutrophil infiltration in breastfed bronchiolitic infants, with a corresponding reduction in disease severity. This study aimed to examine whether respiratory viral etiology and co-infection alters the pattern of neutrophil influx, and the inflammatory mediator profile, resulting in epithelial damage in bronchiolitis.Nasopharyngeal aspirates (NPAs) collected from hospitalized infants were assessed for viruses, soluble protein, cellular infiltrate, interleukin (IL)-6, -8, and myeloperoxidase (MPO).NPAs were collected from 228 bronchiolitic and 14 non-bronchiolitic infants. In the bronchiolitic cohort, human rhinovirus was most prevalent (38%), followed by respiratory syncytial virus (36%), adenovirus (10%), and human metapneumovirus (6%), with 25% positive for viral co-infections and 25% negative for all screened viruses. Viral-induced bronchiolitis was associated with increased cellular infiltrate and protein, above control, and virus-negative infants (P < 0.05). Cellular infiltrate correlated to IL-6, -8, and MPO (r = 0.331, 0.669, and 0.661; P < 0.01). Protein, IL-6, -8, and MPO differed significantly between viral groups; however, the majority of marker values for all groups fall within an overlapping, indistinguishable range, precluding their use as biomarkers of viral etiology. No significant difference was found between single and viral co-infections for any parameter.Bronchiolitic infants presenting with a detectable respiratory virus during hospitalization demonstrated elevated markers of airway tissue inflammation and injury. In this cohort, viral etiology did not discernibly modulate chemokine-mediated neutrophil infiltration and activation. Pediatr Pulmonol. © 2016 Wiley Periodicals, Inc.
- A Rare Case of Hemorrhagic Cystitis in Allogeneic Hematopoietic Stem Cell Transplant Patient. [Journal Article]
- Indian J Hematol Blood Transfus 2016 Jun; 32(Suppl 1):196-200.
Post bone marrow transplant patients are susceptible to atypical infections, especially viral pathogens. The risk increases many folds in cases of allogeneic transplantation, which also receive GVHD prophylaxis. Viral pathogens like cytomegalovirus and herpes are the common ones encountered during follow-up period. However, in recent times there have been reports of a variety of disease manifestations of rare viruses like polyoma virus and adenovirus. These viral infections may play a crucial role in morbidity and mortality in immunocompromised patients. We hereby elaborate the follow-up course of a 36-year-old post allogeneic transplant patient of acute myeloid leukemia who developed adenovirus related haemorrhagic cystitis. Treatment with oral ribavirin lead to dramatic improvement in symptomatology within a week. This cases re-emphasizes the fact that after ruling out the commoner pathogens, it's of utmost importance to strongly consider the atypical pathogens in such cases.
- Infectious and Environmental Influences on the Obesity Epidemic. [REVIEW, JOURNAL ARTICLE]
- Curr Obes Rep 2016 Jul 9.
Over the last two decades, the prevalence of obesity has increased rapidly. While it is intuitively appealing to believe that the causes of obesity are manifestly related to excess dietary intake, combined with a reduced expenditure of energy via a decrease in physical activity, it is also been noted that the evidence for these as the sole causes of the obesity epidemic is incomplete. This has led to the search for other causes of obesity, particularly those which stem from the environment we live in. This review will explore two putative causes of obesity: infections and environmental pollutants. It will focus on the key human infection associated with obesity-human adenovirus 36 (Ad36) and will discuss several environmental pollutants which have been postulated to be involved in the development of obesity: bisphenol A, phthalates and persistent organic pollutants. For each of these, the epidemiology and biological mechanisms underpinning the association of these agents with obesity will be reviewed.
- Structure of the Adenovirus Type 4 (Species E) E3-19K/HLA-A2 Complex Reveals Species-Specific Features in MHC Class I Recognition. [JOURNAL ARTICLE]
- J Immunol 2016 Jul 6.
Adenoviruses (Ads) subvert MHC class I Ag presentation and impair host anti-Ad cellular activities. Specifically, the Ad-encoded E3-19K immunomodulatory protein targets MHC class I molecules for retention within the endoplasmic reticulum of infected cells. We report the x-ray crystal structure of the Ad type 4 (Ad4) E3-19K of species E bound to HLA-A2 at 2.64-Å resolution. Structural analysis shows that Ad4 E3-19K adopts a tertiary fold that is shared only with Ad2 E3-19K of species C. A comparative analysis of the Ad4 E3-19K/HLA-A2 structure with our x-ray structure of Ad2 E3-19K/HLA-A2 identifies species-specific features in HLA-A2 recognition. Our analysis also reveals common binding characteristics that explain the promiscuous, and yet high-affinity, association of E3-19K proteins with HLA-A and HLA-B molecules. We also provide structural insights into why E3-19K proteins do not associate with HLA-C molecules. Overall, our study provides new information about how E3-19K proteins selectively engage with MHC class I to abrogate Ag presentation and counteract activation of CD8(+) T cells. The significance of MHC class I Ag presentation for controlling viral infections, as well as the threats of viral infections in immunocompromised patients, underline our efforts to characterize viral immunoevasins, such as E3-19K.