Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 129
Filter
Add more filters

Publication year range
1.
Cell ; 185(25): 4811-4825.e17, 2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36423629

ABSTRACT

Pediatric SARS-CoV-2 vaccines are needed that elicit immunity directly in the airways as well as systemically. Building on pediatric parainfluenza virus vaccines in clinical development, we generated a live-attenuated parainfluenza-virus-vectored vaccine candidate expressing SARS-CoV-2 prefusion-stabilized spike (S) protein (B/HPIV3/S-6P) and evaluated its immunogenicity and protective efficacy in rhesus macaques. A single intranasal/intratracheal dose of B/HPIV3/S-6P induced strong S-specific airway mucosal immunoglobulin A (IgA) and IgG responses. High levels of S-specific antibodies were also induced in serum, which efficiently neutralized SARS-CoV-2 variants of concern of alpha, beta, and delta lineages, while their ability to neutralize Omicron sub-lineages was lower. Furthermore, B/HPIV3/S-6P induced robust systemic and pulmonary S-specific CD4+ and CD8+ T cell responses, including tissue-resident memory cells in the lungs. Following challenge, SARS-CoV-2 replication was undetectable in airways and lung tissues of immunized macaques. B/HPIV3/S-6P will be evaluated clinically as pediatric intranasal SARS-CoV-2/parainfluenza virus type 3 vaccine.


Subject(s)
COVID-19 Vaccines , COVID-19 , Animals , Humans , Antibodies, Neutralizing , Antibodies, Viral , Macaca mulatta , COVID-19/prevention & control , SARS-CoV-2/genetics
2.
Cell ; 166(3): 609-623, 2016 Jul 28.
Article in English | MEDLINE | ID: mdl-27453470

ABSTRACT

Antibodies capable of neutralizing divergent influenza A viruses could form the basis of a universal vaccine. Here, from subjects enrolled in an H5N1 DNA/MIV-prime-boost influenza vaccine trial, we sorted hemagglutinin cross-reactive memory B cells and identified three antibody classes, each capable of neutralizing diverse subtypes of group 1 and group 2 influenza A viruses. Co-crystal structures with hemagglutinin revealed that each class utilized characteristic germline genes and convergent sequence motifs to recognize overlapping epitopes in the hemagglutinin stem. All six analyzed subjects had sequences from at least one multidonor class, and-in half the subjects-multidonor-class sequences were recovered from >40% of cross-reactive B cells. By contrast, these multidonor-class sequences were rare in published antibody datasets. Vaccination with a divergent hemagglutinin can thus increase the frequency of B cells encoding broad influenza A-neutralizing antibodies. We propose the sequence signature-quantified prevalence of these B cells as a metric to guide universal influenza A immunization strategies.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Influenza A virus/immunology , Influenza Vaccines/immunology , Adult , Amino Acid Sequence , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/genetics , Antibodies, Viral/chemistry , Antibodies, Viral/genetics , B-Lymphocytes/immunology , Epitopes, B-Lymphocyte , Female , Gene Rearrangement, B-Lymphocyte, Heavy Chain , Humans , Immunologic Memory , Influenza A Virus, H5N1 Subtype/immunology , Male , Middle Aged , Models, Molecular , Protein Structure, Tertiary , Structure-Activity Relationship , Young Adult
3.
PLoS Pathog ; 20(5): e1012198, 2024 May.
Article in English | MEDLINE | ID: mdl-38739647

ABSTRACT

Respiratory syncytial virus (RSV) is the most important viral agent of severe pediatric respiratory illness worldwide, but there is no approved pediatric vaccine. Here, we describe the development of the live-attenuated RSV vaccine candidate Min AL as well as engineered derivatives. Min AL was attenuated by codon-pair deoptimization (CPD) of seven of the 11 RSV open reading frames (ORFs) (NS1, NS2, N, P, M, SH and L; 2,073 silent nucleotide substitutions in total). Min AL replicated efficiently in vitro at the permissive temperature of 32°C but was highly temperature sensitive (shut-off temperature of 36°C). When serially passaged at increasing temperatures, Min AL retained greater temperature sensitivity compared to previous candidates with fewer CPD ORFs. However, whole-genome deep-sequencing of passaged Min AL revealed mutations throughout its genome, most commonly missense mutations in the polymerase cofactor P and anti-termination transcription factor M2-1 (the latter was not CPD). Reintroduction of selected mutations into Min AL partially rescued its replication in vitro at temperatures up to 40°C, confirming their compensatory effect. These mutations restored the accumulation of positive-sense RNAs to wild-type (wt) RSV levels, suggesting increased activity by the viral transcriptase, whereas viral protein expression, RNA replication, and virus production were only partly rescued. In hamsters, Min AL and derivatives remained highly restricted in replication in the upper and lower airways, but induced serum IgG and IgA responses to the prefusion form of F (pre F) that were comparable to those induced by wt RSV, as well as robust mucosal and systemic IgG and IgA responses against RSV G. Min AL and derivatives were fully protective against challenge virus replication. The derivatives had increased genetic stability compared to Min AL. Thus, Min AL and derivatives with selected mutations are stable, attenuated, yet highly-immunogenic RSV vaccine candidates that are available for further evaluation.


Subject(s)
Open Reading Frames , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus Vaccines , Vaccines, Attenuated , Virus Replication , Animals , Respiratory Syncytial Virus Vaccines/immunology , Respiratory Syncytial Virus Vaccines/genetics , Vaccines, Attenuated/immunology , Vaccines, Attenuated/genetics , Respiratory Syncytial Virus Infections/immunology , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Infections/virology , Cricetinae , Administration, Intranasal , Codon , Immunity, Mucosal , Antibodies, Viral/immunology , Antibodies, Viral/blood , Humans , Respiratory Syncytial Virus, Human/immunology , Respiratory Syncytial Virus, Human/genetics , Mesocricetus , Respiratory Syncytial Viruses/immunology , Respiratory Syncytial Viruses/genetics
4.
PLoS Pathog ; 19(6): e1011057, 2023 06.
Article in English | MEDLINE | ID: mdl-37352333

ABSTRACT

The pediatric live-attenuated bovine/human parainfluenza virus type 3 (B/HPIV3)-vectored vaccine expressing the prefusion-stabilized SARS-CoV-2 spike (S) protein (B/HPIV3/S-2P) was previously evaluated in vitro and in hamsters. To improve its immunogenicity, we generated B/HPIV3/S-6P, expressing S further stabilized with 6 proline mutations (S-6P). Intranasal immunization of hamsters with B/HPIV3/S-6P reproducibly elicited significantly higher serum anti-S IgA/IgG titers than B/HPIV3/S-2P; hamster sera efficiently neutralized variants of concern (VoCs), including Omicron variants. B/HPIV3/S-2P and B/HPIV3/S-6P immunization protected hamsters against weight loss and lung inflammation following SARS-CoV-2 challenge with the vaccine-matched strain WA1/2020 or VoCs B.1.1.7/Alpha or B.1.351/Beta and induced near-sterilizing immunity. Three weeks post-challenge, B/HPIV3/S-2P- and B/HPIV3/S-6P-immunized hamsters exhibited a robust anamnestic serum antibody response with increased neutralizing potency to VoCs, including Omicron sublineages. B/HPIV3/S-6P primed for stronger anamnestic antibody responses after challenge with WA1/2020 than B/HPIV3/S-2P. B/HPIV3/S-6P will be evaluated as an intranasal vaccine to protect infants against both HPIV3 and SARS-CoV-2.


Subject(s)
COVID-19 , Paramyxoviridae Infections , Cricetinae , Humans , Animals , Cattle , Child , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics , Antibodies, Viral , Viral Fusion Proteins , Vaccines, Attenuated , COVID-19/prevention & control , Parainfluenza Virus 3, Human , Antibodies, Neutralizing
5.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Article in English | MEDLINE | ID: mdl-34876520

ABSTRACT

Single-dose vaccines with the ability to restrict SARS-CoV-2 replication in the respiratory tract are needed for all age groups, aiding efforts toward control of COVID-19. We developed a live intranasal vector vaccine for infants and children against COVID-19 based on replication-competent chimeric bovine/human parainfluenza virus type 3 (B/HPIV3) that express the native (S) or prefusion-stabilized (S-2P) SARS-CoV-2 S spike protein, the major protective and neutralization antigen of SARS-CoV-2. B/HPIV3/S and B/HPIV3/S-2P replicated as efficiently as B/HPIV3 in vitro and stably expressed SARS-CoV-2 S. Prefusion stabilization increased S expression by B/HPIV3 in vitro. In hamsters, a single intranasal dose of B/HPIV3/S-2P induced significantly higher titers compared to B/HPIV3/S of serum SARS-CoV-2-neutralizing antibodies (12-fold higher), serum IgA and IgG to SARS-CoV-2 S protein (5-fold and 13-fold), and IgG to the receptor binding domain (10-fold). Antibodies exhibited broad neutralizing activity against SARS-CoV-2 of lineages A, B.1.1.7, and B.1.351. Four weeks after immunization, hamsters were challenged intranasally with 104.5 50% tissue-culture infectious-dose (TCID50) of SARS-CoV-2. In B/HPIV3 empty vector-immunized hamsters, SARS-CoV-2 replicated to mean titers of 106.6 TCID50/g in lungs and 107 TCID50/g in nasal tissues and induced moderate weight loss. In B/HPIV3/S-immunized hamsters, SARS-CoV-2 challenge virus was reduced 20-fold in nasal tissues and undetectable in lungs. In B/HPIV3/S-2P-immunized hamsters, infectious challenge virus was undetectable in nasal tissues and lungs; B/HPIV3/S and B/HPIV3/S-2P completely protected against weight loss after SARS-CoV-2 challenge. B/HPIV3/S-2P is a promising vaccine candidate to protect infants and young children against HPIV3 and SARS-CoV-2.


Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , SARS-CoV-2/immunology , Administration, Intranasal , Animals , Antibodies, Viral/blood , COVID-19 Vaccines/genetics , COVID-19 Vaccines/immunology , Cricetinae , Genetic Vectors , Immunization , Parainfluenza Virus 3, Bovine/genetics , Parainfluenza Virus 3, Human/genetics , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology
6.
PLoS Pathog ; 17(12): e1010191, 2021 12.
Article in English | MEDLINE | ID: mdl-34965283

ABSTRACT

Recoding viral genomes by introducing numerous synonymous nucleotide substitutions that create suboptimal codon pairs provides new live-attenuated vaccine candidates. Because recoding typically involves a large number of nucleotide substitutions, the risk of de-attenuation is presumed to be low. However, this has not been thoroughly studied. We previously generated human respiratory syncytial virus (RSV) in which the NS1, NS2, N, P, M and SH ORFs were codon-pair deoptimized (CPD) by 695 synonymous nucleotide changes (Min A virus). Min A exhibited a global reduction in transcription and protein synthesis, was restricted for replication in vitro and in vivo, and exhibited moderate temperature sensitivity. Here, we show that under selective pressure by serial passage at progressively increasing temperatures, Min A regained replication fitness and lost its temperature sensitivity. Whole-genome deep sequencing identified numerous missense mutations in several genes, in particular ones accumulating between codons 25 and 34 of the phosphoprotein (P), a polymerase cofactor and chaperone. When re-introduced into Min A, these P mutations restored viral transcription to wt level, resulting in increased protein expression and RNA replication. Molecular dynamic simulations suggested that these P mutations increased the flexibility of the N-terminal domain of P, which might facilitate its interaction with the nucleoprotein N, and increase the functional efficiency of the RSV transcription/replication complex. Finally, we evaluated the effect of the P mutations on Min A replication and immunogenicity in hamsters. Mutation P[F28V] paradoxically reduced Min A replication but not its immunogenicity. The further addition of one missense mutation each in M and L generated a version of Min A with increased genetic stability. Thus, this study provides further insight into the adaptability of large-scale recoded RNA viruses under selective pressure and identified an improved CPD RSV vaccine candidate.


Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus Vaccines , Respiratory Syncytial Virus, Human/genetics , Viral Structural Proteins/genetics , Animals , Chlorocebus aethiops , Cricetinae , Mesocricetus , Mutation , Phosphoproteins/genetics , Transcription, Genetic , Vaccines, Attenuated , Vero Cells
7.
Semin Thromb Hemost ; 49(3): 284-294, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36368692

ABSTRACT

ADAMTS13 (a disintegrin-like metalloprotease domain with thrombospondin type 1 motif, member 13) is a protease of crucial importance in the regulation of the size of von Willebrand factor multimers. Very low ADAMTS13 activity levels result in thrombotic thrombocytopenic purpura, a rare and life-threatening disease. The mechanisms involved can either be acquired (immune-mediated thrombotic thrombocytopenic purpura [iTTP]) or congenital (cTTP, Upshaw-Schulman syndrome) caused by the autosomal recessive inheritance of disease-causing variants (DCVs) located along the ADAMTS13 gene, which is located in chromosome 9q34. Apart from its role in TTP, and as a regulator of microthrombosis, ADAMTS13 has begun to be identified as a prognostic and/or diagnostic marker of other diseases, such as those related to inflammatory processes, liver damage, metastasis of malignancies, sepsis, and different disorders related to angiogenesis. Since its first description almost 100 years ago, the improvement of laboratory tests and the description of novel DCVs along the ADAMTS13 gene have contributed to a better and faster diagnosis of patients under critical conditions. The ability of ADAMTS13 to dissolve platelet aggregates in vitro and its antithrombotic properties makes recombinant human ADAMTS13 treatment a potential therapeutic approach targeting not only patients with cTTP but also other medical conditions.


Subject(s)
Purpura, Thrombotic Thrombocytopenic , Humans , ADAM Proteins/genetics , ADAMTS13 Protein/genetics , Purpura, Thrombotic Thrombocytopenic/diagnosis , Purpura, Thrombotic Thrombocytopenic/genetics , Purpura, Thrombotic Thrombocytopenic/therapy , von Willebrand Factor
8.
J Nerv Ment Dis ; 210(12): 966-969, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36449722

ABSTRACT

ABSTRACT: Body dysmorphic disorder (BDD) is a mental illness currently classified as part of the "Obsessive-Compulsive and Related Disorders" (OCRD) chapter in both the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) and in the ICD-11. This is not the case for illness anxiety disorder/hypochondriasis (IAD/HC), as IAD is classified in the chapter "Somatic Symptom and Related Disorders" in DSM-5, and in ICD-11, under the name HC, it is classified along with BDD in the OCRD chapter.In this article, we aim to describe a case of comorbid BDD and IAD/HC in a young adult Portuguese man. We then aim to review these diagnoses in light of their current classification in DSM-5 and ICD-11, with a particular emphasis in the divergent classification of IAD/HC, namely, the pertinence of its inclusion in the OCRD.


Subject(s)
Body Dysmorphic Disorders , International Classification of Diseases , Male , Young Adult , Humans , Diagnostic and Statistical Manual of Mental Disorders , Hypochondriasis/diagnosis , Body Dysmorphic Disorders/diagnosis , Anxiety Disorders/diagnosis
9.
J Virol ; 95(2)2020 12 22.
Article in English | MEDLINE | ID: mdl-33115876

ABSTRACT

Live-attenuated pediatric vaccines for intranasal administration are being developed for human respiratory syncytial virus (RSV), an important worldwide pediatric respiratory pathogen that lacks a licensed vaccine or suitable antiviral drug. We evaluated a prime-boost strategy in which primary immunization with RSV was boosted by secondary immunization with RSV or with a chimeric recombinant bovine/human parainfluenza virus type 3 (rB/HPIV3) vector expressing the RSV fusion F protein. The vector-expressed F protein had been engineered (DS-Cav1 mutations) for increased stability in the highly immunogenic prefusion (pre-F) conformation, with or without replacement of its transmembrane and cytoplasmic tail domains with their counterparts from bovine parainfluenza virus type 3 (BPIV3) F protein to direct incorporation into the vector virion for increased immunogenicity. In hamsters that received a primary infection with RSV, a booster infection with RSV ∼6 weeks later was completely restricted for producing infectious virus but induced a significant increase in the serum RSV-plaque-reduction neutralizing antibody titer (RSV-PRNT). Boosting instead with the rB/HPIV3-RSV-pre-F vectors resulted in efficient replication and induced significantly higher RSV-PRNTs than RSV. In African green monkeys that received a primary infection with RSV, a booster infection with RSV ∼2, ∼6, or ∼15 months later was highly restricted, whereas booster infections with the vectors had robust replication. Compared with RSV, boosts with the vectors induced 7- to 15-fold higher titers of RSV-specific serum antibodies with high neutralizing activity, as well as significantly higher titers of RSV-specific mucosal IgA antibodies. These findings support further development of this heterologous prime-boost strategy.IMPORTANCE Immune responses to RSV in infants can be reduced due to immunological immaturity and immunosuppression by RSV-specific maternal antibodies. In infants and young children, two infections with wild-type RSV typically are needed to achieve the titers of RSV-specific serum antibodies and protection against illness that are observed in adults. Therefore, a boost might substantially improve the performance of live pediatric RSV vaccines presently being developed. Hamsters and African green monkeys received a primary intranasal infection with RSV and were given a boost with RSV or a parainfluenza virus (PIV) vector expressing RSV fusion protein engineered for enhanced immunogenicity. The RSV boost was highly restricted but induced a significant increase in serum RSV-neutralizing antibodies. The PIV vectors replicated efficiently and induced significantly higher antibody responses. The use of an attenuated PIV vector expressing RSV antigen to boost a primary immunization with an attenuated RSV warrants further evaluation.


Subject(s)
Immunization, Secondary/methods , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Vaccines/immunology , Respiratory Syncytial Virus, Human/immunology , Respirovirus/genetics , Viral Fusion Proteins/immunology , Animals , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Chlorocebus aethiops , Cricetinae , Immunogenicity, Vaccine , Mutation , Respiratory Syncytial Virus Vaccines/administration & dosage , Respiratory Syncytial Virus Vaccines/genetics , Respiratory Syncytial Virus, Human/genetics , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Viral Fusion Proteins/genetics
10.
J Clin Nurs ; 30(21-22): 3055-3071, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34101275

ABSTRACT

AIMS AND OBJECTIVES: To map nursing interventions, their characteristics, and outcomes, in promoting self-care of the person with a tracheostomy. BACKGROUND: The development of competencies in self-care of a person with a tracheostomy is recognised as one of the most significant nursing intervention areas for the promotion of autonomy, prevention of complications and adaptation. Identifying nursing interventions for the promotion of self-care of the person with a tracheostomy enables enhanced clinical practice knowledge within different care contexts and the identification of gaps in the available evidence. DESIGN: The Joanna Briggs Institute (JBI) methodology was used to perform this scoping review. METHOD: A search was conducted on the CINAHL, Scopus, Web of Science, PubMed, JBI Database of Systematic Reviews and Implementation Reports, and Cochrane Database of Systematic Reviews. The search for grey literature included Portugal´s Open Access Scientific Repository, OpenGrey, and ProQuest Dissertations and Theses. Studies published in Portuguese, English, Spanish and French were included. The PRISMA-ScR checklist was used. RESULTS: From a total of 4,224 identified articles, 31 were included in this review. Multiple nursing interventions were identified and grouped into four types of action: informing, managing, determining and attending. Although most interventions are implemented with the face-to-face method, there is a growing interest in using technologies for this purpose. The dose is the characteristic most poorly described in interventions. Various results were obtained; however, valid assessment tools were not always used. CONCLUSIONS: Designing and testing intervention programmes for the promotion of self-care of the person with a tracheostomy is necessary, based on available and robust evidence to guide clinical practice. RELEVANCE TO CLINICAL PRACTICE: This review allowed to systematise nursing interventions to promote self-care of the person with a tracheostomy. The use of combined interventions and methodologies is likely to be more effective in care delivery.


Subject(s)
Self Care , Tracheostomy , Delivery of Health Care , Humans
11.
J Virol ; 92(9)2018 05 01.
Article in English | MEDLINE | ID: mdl-29444938

ABSTRACT

Pandemic live attenuated influenza vaccines (pLAIV) prime subjects for a robust neutralizing antibody response upon subsequent administration of a pandemic inactivated subunit vaccine (pISV). However, a difference was not detected in H5-specific memory B cells in the peripheral blood between pLAIV-primed and unprimed subjects prior to pISV boost. To investigate the mechanism underlying pLAIV priming, we vaccinated groups of 12 African green monkeys (AGMs) with H5N1 pISV or pLAIV alone or H5N1 pLAIV followed by pISV and examined immunity systemically and in local draining lymph nodes (LN). The AGM model recapitulated the serologic observations from clinical studies. Interestingly, H5N1 pLAIV induced robust germinal center B cell responses in the mediastinal LN (MLN). Subsequent boosting with H5N1 pISV drove increases in H5-specific B cells in the axillary LN, spleen, and circulation in H5N1 pLAIV-primed animals. Thus, H5N1 pLAIV primes localized B cell responses in the MLN that are recalled systemically following pISV boost. These data provide mechanistic insights for the generation of robust humoral responses via prime-boost vaccination.IMPORTANCE We have previously shown that pandemic live attenuated influenza vaccines (pLAIV) prime for a rapid and robust antibody response on subsequent administration of inactivated subunit vaccine (pISV). This is observed even in individuals who had undetectable antibody (Ab) responses following the initial vaccination. To define the mechanistic basis of pLAIV priming, we turned to a nonhuman primate model and performed a detailed analysis of B cell responses in systemic and local lymphoid tissues following prime-boost vaccination with pLAIV and pISV. We show that the nonhuman primate model recapitulates the serologic observations from clinical studies. Further, we found that pLAIVs induced robust germinal center B cell responses in the mediastinal lymph node. Subsequent boosting with pISV in pLAIV-primed animals resulted in detection of B cells in the axillary lymph nodes, spleen, and peripheral blood. We demonstrate that intranasally administered pLAIV elicits a highly localized germinal center B cell response in the mediastinal lymph node that is rapidly recalled following pISV boost into germinal center reactions at numerous distant immune sites.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , B-Lymphocytes/immunology , Influenza A Virus, H5N1 Subtype/immunology , Influenza Vaccines/immunology , Vaccines, Attenuated/immunology , Vaccines, Subunit/immunology , Administration, Intranasal , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Chlorocebus aethiops , Female , Humans , Influenza, Human/prevention & control , Lymph Nodes/cytology , Lymph Nodes/immunology , Lymphocyte Count , Male , Vaccination
12.
Proc Natl Acad Sci U S A ; 112(30): 9430-5, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26170284

ABSTRACT

H5N1 avian influenza viruses remain a threat to public health mainly because they can cause severe infections in humans. These viruses are widespread in birds, and they vary in antigenicity forming three major clades and numerous antigenic variants. The most important features of the human monoclonal antibody FLD194 studied here are its broad specificity for all major clades of H5 influenza HAs, its high affinity, and its ability to block virus infection, in vitro and in vivo. As a consequence, this antibody may be suitable for anti-H5 therapy and as a component of stockpiles, together with other antiviral agents, for health authorities to use if an appropriate vaccine was not available. Our mutation and structural analyses indicate that the antibody recognizes a relatively conserved site near the membrane distal tip of HA, near to, but distinct from, the receptor-binding site. Our analyses also suggest that the mechanism of infectivity neutralization involves prevention of receptor recognition as a result of steric hindrance by the Fc part of the antibody. Structural analyses by EM indicate that three Fab fragments are bound to each HA trimer. The structure revealed by X-ray crystallography is of an HA monomer bound by one Fab. The monomer has some similarities to HA in the fusion pH conformation, and the monomer's formation, which results from the presence of isopropanol in the crystallization solvent, contributes to considerations of the process of change in conformation required for membrane fusion.


Subject(s)
Antibodies, Monoclonal/chemistry , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinins/chemistry , Influenza A Virus, H5N1 Subtype/immunology , Animals , Antibodies, Neutralizing/chemistry , Antibodies, Viral/chemistry , Binding Sites , Crystallography, X-Ray , Epitopes/chemistry , Humans , Hydrogen-Ion Concentration , Immunoglobulin Fragments/chemistry , Immunoglobulin G/chemistry , Influenza Vaccines/immunology , Mice , Mice, Inbred BALB C , Neutralization Tests , Protein Binding , Protein Conformation , Solvents/chemistry
13.
Can J Infect Dis Med Microbiol ; 2016: 6239434, 2016.
Article in English | MEDLINE | ID: mdl-27528878

ABSTRACT

Background. Intestinal parasitic infections constitute a major public health problem that is frequently associated with poverty, inadequate sanitation, and the nutritional status of the population. Objective. The aim of the present study is to investigate the possible association of parasitic infections, sanitary conditions, hygiene practices, and the nutritional and socioeconomic status of a poor youth population. Methods. A cross-sectional study was conducted with 367 children and adolescents inhabiting a substandard settlement in the urban area of Maceió (Alagoas State, Brazil). Data collection included socioeconomic status, anthropometric measurements, fecal sample examinations, and laboratory blood analysis. The identification of factors associated with gastrointestinal parasitic infections was undertaken through bi- and multivariate analyses. Results. Stool sample analysis obtained from 300 individuals revealed that 204 (68%) were infected with at least one parasite species and of these 130 (63.7%) were polyparasitized. No significant associations were identified between low height for age (stunted), parasitic infections, and polyparasitism. There was also no association between family income and parasitosis. However, low socioeconomic status proved to be a potential risk factor for parasitic infections. Conclusion. Actions must be taken to improve sanitation, housing, and environmental conditions in order to eliminate the risk factors for parasitic infections, and thereby guarantee a better quality of life for this population.

14.
J Virol ; 88(21): 12339-47, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25122786

ABSTRACT

UNLABELLED: Live attenuated influenza vaccines in the United States are derived from a human virus that is temperature sensitive (ts), characterized by restricted (≥ 100-fold) replication at 39 °C. The ts genetic signature (ts sig) has been mapped to 5 loci in 3 genes: PB1 (391 E, 581 G, and 661 T), PB2 (265 S), and NP (34 G). However, when transferred into avian and swine influenza viruses, only partial ts and attenuation phenotypes occur. To investigate the reason for this, we introduced the ts sig into the human origin virus A/WSN/33 (WSN), the avian-origin virus A/Vietnam/1203/04 (VN04), and the swine origin triple-reassortant 2009 pandemic H1N1 virus A/California/07/2009 (CA07), which contains gene segments from human, avian, and swine viruses. The VN04(ts sig) and CA07(ts sig) viruses replicated efficiently in Madin-Darby canine kidney (MDCK) cells at 39 °C, but the replication of WSN(ts sig) was restricted ≥ 100-fold compared to that at 33 °C. Reassortant CA07(ts sig) viruses were generated with individual polymerase gene segments from WSN, and vice versa. Only ts sig viruses with a PB2 gene segment derived from WSN were restricted in replication ≥ 100-fold at 39 °C. In ferrets, the CA07(ts sig) virus replicated in the upper and lower respiratory tract, but the replication of a reassortant CA07(ts sig) virus with a WSN PB2 gene was severely restricted in the lungs. Taken together, these data suggest that the origin of the PB2 gene segment influences the ts phenotype in vitro and attenuation in vivo. This could have implications for the design of novel live vaccines against animal origin influenza viruses. IMPORTANCE: Live attenuated influenza vaccines (LAIVs) on temperature-sensitive (ts) backbones derived from animal origin influenza viruses are being sought for use in the poultry and swine industries and to protect people against animal origin influenza. However, inserting the ts genetic signature from a licensed LAIV backbone fails to fully attenuate these viruses. Our data indicate this is associated with the presence of a PB2 gene segment derived from an avian influenza virus. We show that a reassortant 2009 pandemic H1N1 virus with the ts signature from a licensed LAIV donor virus is ts in vitro and attenuated in vivo when the PB2 gene is derived from a human origin virus but not from an avian virus. Our study provides information that could benefit the rational design of alternative LAIV backbones against animal origin influenza viruses.


Subject(s)
Influenza A virus/physiology , RNA-Binding Proteins/metabolism , RNA-Dependent RNA Polymerase/metabolism , Reassortant Viruses/physiology , Viral Core Proteins/metabolism , Viral Proteins/metabolism , Virus Replication/radiation effects , Animals , Birds , Cell Line , Disease Models, Animal , Dogs , Female , Ferrets , Humans , Influenza A virus/genetics , Influenza A virus/pathogenicity , Influenza A virus/radiation effects , Mutation , Nucleocapsid Proteins , Orthomyxoviridae , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology , RNA-Binding Proteins/genetics , RNA-Dependent RNA Polymerase/genetics , Reassortant Viruses/genetics , Reassortant Viruses/pathogenicity , Reassortant Viruses/radiation effects , Respiratory System/pathology , Respiratory System/virology , Reverse Genetics , Swine , Temperature , United States , Viral Core Proteins/genetics , Viral Proteins/genetics
15.
J Virol ; 88(12): 7016-23, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24719414

ABSTRACT

UNLABELLED: Live attenuated H7N9 influenza vaccine viruses that possess the hemagglutinin (HA) and neuraminidase (NA) gene segments from the newly emerged wild-type (wt) A/Anhui/1/2013 (H7N9) and six internal protein gene segments from the cold-adapted influenza virus A/Ann Arbor/6/60 (AA ca) were generated by reverse genetics. The reassortant virus containing the original wt A/Anhui/1/2013 HA and NA sequences replicated poorly in eggs. Multiple variants with amino acid substitutions in the HA head domain that improved viral growth were identified by viral passage in eggs and MDCK cells. The selected vaccine virus containing two amino acid changes (N133D/G198E) in the HA improved viral titer by more than 10-fold (reached a titer of 10(8.6) fluorescent focus units/ml) without affecting viral antigenicity. Introduction of these amino acid changes into an H7N9 PR8 reassortant virus also significantly improved viral titers and HA protein yield in eggs. The H7N9 ca vaccine virus was immunogenic in ferrets. A single dose of vaccine conferred complete protection of ferrets from homologous wt A/Anhui/1/2013 (H7N9) and nearly complete protection from heterologous wt A/Netherlands/219/2003 (H7N7) challenge infection. Therefore, this H7N9 live attenuated influenza vaccine (LAIV) candidate has been selected for vaccine manufacture and clinical evaluation to protect humans from wt H7N9 virus infection. IMPORTANCE: In response to the recent avian H7N9 influenza virus infection in humans, we developed a live attenuated H7N9 influenza vaccine (LAIV) with two amino acid substitutions in the viral HA protein that improved vaccine yield by 10-fold in chicken embryonated eggs, the substrate for vaccine manufacture. The two amino acids also improved the antigen yield for inactivated H7N9 vaccines, demonstrating that this finding could great facilitate the efficiency of H7N9 vaccine manufacture. The candidate H7N9 LAIV was immunogenic and protected ferrets against homologous and heterologous wild-type H7 virus challenge, making it suitable for use in protecting humans from H7 infection.


Subject(s)
Influenza A Virus, H7N7 Subtype/immunology , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Animals , Cross Protection , Disease Models, Animal , Female , Ferrets , Hemagglutinin Glycoproteins, Influenza Virus/administration & dosage , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Humans , Influenza A Virus, H7N7 Subtype/genetics , Influenza A virus/classification , Influenza A virus/genetics , Influenza A virus/immunology , Influenza Vaccines/administration & dosage , Influenza Vaccines/genetics , Influenza, Human/immunology , Influenza, Human/virology , Male , Neuraminidase/administration & dosage , Neuraminidase/genetics , Neuraminidase/immunology , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology
16.
J Virol ; 87(19): 10884-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23864613

ABSTRACT

The substitution of glutamic acid (E) for lysine (K) at position 627 of the PB2 protein of avian H5N1 viruses has been identified as a virulence and host range determinant for infection of mammals. Here, we report that the E-to-K host-adaptive mutation in the PB2 gene appeared from day 4 and 5 along the respiratory tracts of mice and was complete by day 6 postinoculation. This mutation correlated with efficient replication of the virus in mice.


Subject(s)
Influenza A Virus, H5N1 Subtype/pathogenicity , Mutation/genetics , Orthomyxoviridae Infections/virology , Respiratory System/virology , Viral Proteins/genetics , Virulence , Virus Replication , Amino Acid Substitution , Animals , Host Specificity , Mice , Orthomyxoviridae Infections/genetics , Orthomyxoviridae Infections/pathology , Respiratory System/metabolism , Respiratory System/pathology , Viral Proteins/metabolism
17.
Aten Primaria ; 46 Suppl 5: 101-6, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25476044

ABSTRACT

INTRODUCTION: The phenomenon of adherence to treatment is a motive of worry from the scientific community, since it is considered as a worldwide problem of high magnitude. The implications are of great relevance in morbidity, mortality, in the significant increase in the consumption of health care and in the costs to the health system, particularly in patients with ischemic heart disease. We intend to evaluate adherence to treatment and relate beliefs about medicines with adherence to treatment. MATERIAL AND METHODS: This study is descriptive-correlational and cross-sectional. It was performed on 254 patients with ischemic heart disease who were in follow-up consultation in the hospital at the time of the questionnaire application. Data collection was performed through a self-administered questionnaire, integrating the following scales: Measure Adherence to Treatment and Beliefs about Medicines Questionnaire. RESULTS: The patients had a mean age of 66.94 years (SD=11.62), 74% were male, 73.2% were married, 69.3% had education up to the "4th grade", 57.1% lived in the village, 70.1% were retired and 49.6% had an income below "one minimum wage". We found that 50.4% of patients did not adhere to treatment. Women had a strong belief in the specific needs of the prescribed medication, while men expressed greater belief in relation to long-term side effects (P>.05). Patients who expressed a low belief about the harmful potential of medicines revealed predictors of adherence to medication. CONCLUSION: The results are consistent with previous studies in which individuals with lower beliefs in specific concerns reported higher rates of adherence to medication.


Subject(s)
Attitude to Health , Health Knowledge, Attitudes, Practice , Medication Adherence/statistics & numerical data , Myocardial Ischemia/drug therapy , Myocardial Ischemia/psychology , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged
18.
Nat Commun ; 15(1): 3553, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38670948

ABSTRACT

Immunization via the respiratory route is predicted to increase the effectiveness of a SARS-CoV-2 vaccine. Here, we evaluate the immunogenicity and protective efficacy of one or two doses of a live-attenuated murine pneumonia virus vector expressing SARS-CoV-2 prefusion-stabilized spike protein (MPV/S-2P), delivered intranasally/intratracheally to male rhesus macaques. A single dose of MPV/S-2P is highly immunogenic, and a second dose increases the magnitude and breadth of the mucosal and systemic anti-S antibody responses and increases levels of dimeric anti-S IgA in the airways. MPV/S-2P also induces S-specific CD4+ and CD8+ T-cells in the airways that differentiate into large populations of tissue-resident memory cells within a month after the boost. One dose induces substantial protection against SARS-CoV-2 challenge, and two doses of MPV/S-2P are fully protective against SARS-CoV-2 challenge virus replication in the airways. A prime/boost immunization with a mucosally-administered live-attenuated MPV vector could thus be highly effective in preventing SARS-CoV-2 infection and replication.


Subject(s)
Antibodies, Viral , COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Macaca mulatta , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Animals , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/genetics , COVID-19/prevention & control , COVID-19/immunology , COVID-19/virology , Male , Antibodies, Viral/immunology , Mice , CD8-Positive T-Lymphocytes/immunology , Genetic Vectors/immunology , Genetic Vectors/genetics , Antibodies, Neutralizing/immunology , Administration, Intranasal , Vaccines, Attenuated/immunology , Vaccines, Attenuated/administration & dosage , Immunoglobulin A/immunology , CD4-Positive T-Lymphocytes/immunology , Humans
19.
J Virol ; 86(5): 2706-14, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22205751

ABSTRACT

Highly pathogenic avian influenza (HPAI) viruses of the H5 and H7 subtypes typically possess multiple basic amino acids around the cleavage site (MBS) of their hemagglutinin (HA) protein, a recognized virulence motif in poultry. To determine the importance of the H5 HA MBS as a virulence factor in mammals, recombinant wild-type HPAI A/Vietnam/1203/2004 (H5N1) viruses that possessed (H5N1) or lacked (ΔH5N1) the H5 HA MBS were generated and evaluated for their virulence in BALB/c mice, ferrets, and African green monkeys (AGMs) (Chlorocebus aethiops). The presence of the H5 HA MBS was associated with lethality, significantly higher virus titers in the respiratory tract, virus dissemination to extrapulmonary organs, lymphopenia, significantly elevated levels of proinflammatory cytokines and chemokines, and inflammation in the lungs of mice and ferrets. In AGMs, neither H5N1 nor ΔH5N1 virus was lethal and neither caused clinical symptoms. The H5 HA MBS was associated with mild enhancement of replication and delayed virus clearance. Thus, the contribution of H5 HA MBS to the virulence of the HPAI H5N1 virus varies among mammalian hosts and is most significant in mice and ferrets and less remarkable in nonhuman primates.


Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus/metabolism , Host Specificity , Influenza A Virus, H5N1 Subtype/physiology , Mammals/virology , Orthomyxoviridae Infections/veterinary , Orthomyxoviridae Infections/virology , Virulence Factors/metabolism , Amino Acid Motifs , Animals , Chlorocebus aethiops , Female , Ferrets , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Humans , Influenza A Virus, H5N1 Subtype/genetics , Influenza A Virus, H5N1 Subtype/pathogenicity , Male , Mice , Mice, Inbred BALB C , Protein Processing, Post-Translational , Virulence Factors/chemistry , Virulence Factors/genetics
20.
PLoS Pathog ; 7(12): e1002443, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22241979

ABSTRACT

The epidemiological success of pandemic and epidemic influenza A viruses relies on the ability to transmit efficiently from person-to-person via respiratory droplets. Respiratory droplet (RD) transmission of influenza viruses requires efficient replication and release of infectious influenza particles into the air. The 2009 pandemic H1N1 (pH1N1) virus originated by reassortment of a North American triple reassortant swine (TRS) virus with a Eurasian swine virus that contributed the neuraminidase (NA) and M gene segments. Both the TRS and Eurasian swine viruses caused sporadic infections in humans, but failed to spread from person-to-person, unlike the pH1N1 virus. We evaluated the pH1N1 and its precursor viruses in a ferret model to determine the contribution of different viral gene segments on the release of influenza virus particles into the air and on the transmissibility of the pH1N1 virus. We found that the Eurasian-origin gene segments contributed to efficient RD transmission of the pH1N1 virus likely by modulating the release of influenza viral RNA-containing particles into the air. All viruses replicated well in the upper respiratory tract of infected ferrets, suggesting that factors other than viral replication are important for the release of influenza virus particles and transmission. Our studies demonstrate that the release of influenza viral RNA-containing particles into the air correlates with increased NA activity. Additionally, the pleomorphic phenotype of the pH1N1 virus is dependent upon the Eurasian-origin gene segments, suggesting a link between transmission and virus morphology. We have demonstrated that the viruses are released into exhaled air to varying degrees and a constellation of genes influences the transmissibility of the pH1N1 virus.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza, Human/transmission , Models, Biological , Pandemics , Aerosols , Animals , Cell Line , Dogs , Ferrets , Genes, Viral/genetics , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/metabolism , Influenza A Virus, H1N1 Subtype/pathogenicity , Influenza A Virus, H1N1 Subtype/ultrastructure , Influenza, Human/epidemiology , Influenza, Human/genetics , Influenza, Human/metabolism , Neuraminidase/genetics , Neuraminidase/metabolism , North America , Viral Proteins/genetics , Viral Proteins/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL