Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Fish Shellfish Immunol ; 150: 109565, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38636740

RESUMO

The jawless vertebrates (agnathans/cyclostomes) are ancestral animals comprising lampreys and hagfishes as the only extant representatives. They possess an alternative adaptive immune system (AIS) that uses leucine-rich repeats (LRR)-based variable lymphocyte receptors (VLRs) instead of the immunoglobulin (Ig)-based antigen receptors of jawed vertebrates (gnathostomes). The different VLR types are expressed on agnathan lymphocytes and functionally resemble gnathostome antigen receptors. In particular, VLRB is functionally similar to the B cell receptor and is expressed and secreted by B-like lymphocytes as VLRB antibodies that bind antigens with high affinity and specificity. The potential repertoire scale of VLR-based antigen receptors is believed to be at least comparable to that of Ig-based systems. VLR proteins inherently possess characteristics that render them excellent candidates for biotechnological development, including tractability to recombinant approaches. In recent years, scientists have explored the biotechnological development and utility of VLRB proteins as alternatives to conventional mammalian antibodies. The VLRB antibody platform represents a non-traditional approach to generating a highly diverse repertoire of unique antibodies. In this review, we first describe some aspects of the biology of the AIS of the jawless vertebrates, which recognizes antigens by means of unique receptors. We then summarize reports on the development of VLRB-based antibodies and their applications, particularly those from the inshore hagfish (Eptatretus burgeri) and their potential uses to address microbial diseases in aquaculture. Hagfish VLRB antibodies (we call Ccombodies) are being developed and improved, while obstacles to the advancement of the VLRB platform are being addressed to utilize VLRBs effectively as tools in immunology. VLRB antibodies for novel antigen targets are expected to emerge to provide new opportunities to tackle various scientific questions. We anticipate a greater interest in the agnathan AIS in general and particularly in the hagfish AIS for greater elucidation of the evolution of adaptive immunity and its applications to address microbial pathogens in farmed aquatic animals and beyond.


Assuntos
Doenças dos Peixes , Feiticeiras (Peixe) , Animais , Feiticeiras (Peixe)/imunologia , Feiticeiras (Peixe)/genética , Doenças dos Peixes/imunologia , Imunidade Adaptativa , Receptores de Antígenos/genética , Receptores de Antígenos/imunologia , Proteínas de Peixes/imunologia , Proteínas de Peixes/genética
2.
Ann Biomed Eng ; 52(5): 1115-1118, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37530906

RESUMO

Advancements in artificial intelligence (AI) provide many helpful tools for healthcare, one of which includes AI chatbots that use natural language processing to create humanlike, conversational dialog. These chatbots have general cognitive skills and are able to engage with clinicians and patients to discuss patients' health conditions and what they may be at risk for. While chatbot engines have access to a wide range of medical texts and research papers, they currently provide high-level, generic responses and are limited in their ability to provide diagnostic guidance and clinical advice to patients on an individual level. The essay discusses the use of retrieval-augmented generation (RAG), which can be used to improve the specificity of user-entered prompts and thereby enhance the detail in AI chatbot responses. By embedding more recent clinical data and trusted medical sources, such as clinical guidelines, into the chatbot models, AI chatbots can provide more patient-specific guidance, faster diagnoses and treatment recommendations, and greater improvement of patient outcomes.


Assuntos
Inteligência Artificial , Software , Humanos , Tomada de Decisão Clínica , Tecnologia
3.
Fish Shellfish Immunol ; 142: 109007, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37625734

RESUMO

Fish diseases caused by viruses are a major threat to aquaculture. Development of disease protection strategies for sustainable fish aquaculture requires a better understanding of the immune mechanisms involved in antiviral defence. The innate and adaptive arms of the vertebrate immune system collaborate to mount an effective defence against viral pathogens. The T lymphocyte components of the adaptive immune system, comprising two major classes (helper T, Th or CD4+ and cytotoxic T lymphocytes, CTLs or CD8+ T cells), are responsible for cell-mediated immune responses. In particular, CD4+ T cells and their different subsets orchestrate the actions of various other immune cells during immune responses, making CD4+ T cells central drivers of responses to pathogens and vaccines. CD4+ T cells are also present in teleost fish. Here we review the literature that reported the use of antibodies against CD4 in a few teleost fish species and transcription profiling of Th cell-relevant genes in the context of viral infections and virus-relevant immunomodulation. Studies reveal massive CD4+ T cell proliferation and expression of key cytokines, transcription factors, and effector molecules that evoke mammalian Th cell responses. We also discuss gaps in the current understanding and evaluation of teleost CD4+ T cell responses and how development and application of novel tools and approaches to interrogate such responses could bridge these gaps. A greater understanding of fish Th cell responses will further illuminate the evolution of vertebrate adaptive immunity, inform strategies to address viral infections in aquaculture, and could further foster fish as model organisms.


Assuntos
Viroses , Vírus , Animais , Linfócitos T CD8-Positivos , Peixes , Linfócitos T CD4-Positivos , Mamíferos
4.
Cureus ; 15(7): e41350, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37546125

RESUMO

Cerebral venous thrombosis (CVT) is a rare condition characterized by the obstruction of cerebral venous sinuses or cortical veins, leading to stroke-like symptoms. This case report presents a case of a 74-year-old male with isolated unilateral abducens nerve palsy as the sole sign of CVT, without accompanying symptoms or focal deficits. Neuroimaging, including CT and magnetic resonance venography, confirmed the diagnosis of CVT with a thrombus in the right transverse sinus. The patient was co-managed with the medical team and initiated on anticoagulation therapy. Follow-up showed resolution of diplopia and improvement in extraocular muscle movements. Unilateral abducens nerve palsy in CVT is rare, with most cases presenting as bilateral palsy. The case report emphasizes the importance of considering CVT in the differential diagnosis of isolated abducens nerve palsy and highlights the role of neuroimaging in early detection. Timely diagnosis and appropriate management are crucial for favorable outcomes in CVT cases. Further research is needed to enhance understanding of the pathophysiology, prognosis, and optimal management of this uncommon presentation.

5.
Ann Biomed Eng ; 51(9): 1906-1909, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37355478

RESUMO

The implementation of technology in healthcare has revolutionized patient-centered decision making by providing contextualized information about a patient's healthcare journey, leading to increased efficiency (Keyworth et al. in BMC Med Inform Decis Mak 18:93, 2018, https://doi.org/10.1186/s12911-018-0661-3 ). Artificial intelligence has been integrated within Electronic Health Records (EHR) to prompt screenings or diagnostic tests based on a patient's holistic health profile. While larger hospitals have already widely adopted these technologies, free clinics hold lower utilization of these advanced capability EHRs. The patient population at a free clinic faces a multitude of factors that limits their access to comprehensive care, thus requiring necessary efforts and measures to close the gap in healthcare disparities. Emerging Artificial Intelligence (AI) technology, such as OpenAI's ChatGPT, GPT-4, and other large language models (LLMs) have remarkable potential to improve patient care outcomes, promote health equity, and enhance comprehensive and holistic care in resource-limited settings. This paper aims to identify areas in which integrating these LLM AI advancements into free clinics operations can optimize and streamline healthcare delivery to underserved patient populations. This paper also identifies areas of improvements in GPT that are necessary to deliver those services.


Assuntos
Inteligência Artificial , Promoção da Saúde , Humanos , Hospitais , Tecnologia , Acessibilidade aos Serviços de Saúde
6.
Microbiol Res ; 257: 126973, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35085841

RESUMO

With recent initiatives to ban bisphenol A (BPA) in certain commercial products, manufacturers shifted to the production and use of BPA analogues. However, some of these BPA alternatives still possess endocrine disruptive activities. Many fungal enzymes are known to biodegrade phenolic compounds, such as BPA. However, the activity of these enzymes on BPA analogues remains unexplored. This study reports a secreted laccase from the endophytic fungus Diaporthe longicolla capable of degrading an impressive range of bisphenol analogues. The secreted crude enzymes are optimally active at pH 5 from 39 °C to 60 °C, efficiently degrading BPA as well as BPA analogues BPB, BPC, BPE and BPF. A purified form of laccase was identified from the crude fungal extract using FPLC and peptide sequencing. Furthermore, BPA induced the expression of this D. longicolla laccase gene. Overall, this paper demonstrated that the crude laccase enzyme from D. longicolla metabolizes BPA and select analogues, implicating the potential role of this fungus to remove environmental bisphenols.


Assuntos
Compostos Benzidrílicos , Lacase , Ascomicetos , Lacase/genética , Fenóis , Phomopsis
7.
Artigo em Inglês | MEDLINE | ID: mdl-33809592

RESUMO

The ubiquitous occurrence of heavy metals in the aquatic environment remains a serious environmental and health issue. The recovery of metals from wastes and their use for the abatement of toxic heavy metals from contaminated waters appear to be practical approaches. In this study, manganese was recovered from groundwater treatment sludge via reductive acid leaching and converted into spherical aggregates of high-purity MnO2. The as-synthesized MnO2 was used to adsorb Cu(II) and Pb(II) from single-component metal solutions. High metal uptake of 119.90 mg g-1 for Cu(II) and 177.89 mg g-1 for Pb(II) was attained at initial metal ion concentration, solution pH, and temperature of 200 mg L-1, 5.0, and 25 °C, respectively. The Langmuir isotherm model best described the equilibrium metal adsorption, indicating that a single layer of Cu(II) or Pb(II) was formed on the surface of the MnO2 adsorbent. The pseudo-second-order model adequately fit the Cu(II) and Pb(II) kinetic data confirming that chemisorption was the rate-limiting step. Thermodynamic studies revealed that Cu(II) or Pb(II) adsorption onto MnO2 was spontaneous, endothermic, and had increased randomness. Overall, the use of MnO2 prepared from groundwater treatment sludge is an effective, economical, and environmentally sustainable substitute to expensive reagents for toxic metal ion removal from water matrices.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Compostos de Manganês , Óxidos , Esgotos , Termodinâmica , Poluentes Químicos da Água/análise
8.
Chemosphere ; 274: 129518, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33540313

RESUMO

Dyes are hazardous compounds commonly found in industrial wastewaters. Efficient and inexpensive removal of dye molecules from the water matrix has been demonstrated by adsorption processes. Magnetic nano-adsorbents, such as metal ferrites, can be efficiently recovered from the reaction mixture after treating the pollutant. Herein, MFe2O4@GO (M = Cu, Co or Ni) was synthesized via solution combustion method for the removal of dye molecules from aqueous solutions. The characteristics of the MFe2O4@GO, including surface area and pore diameter, surface functional groups, and elemental composition, were examined. Methylene blue was used as representative dye pollutant. Batch adsorption results conformed to the Langmuir isotherm. Maximum adsorption capacities of the MFe2O4@GO (M = Cu, Co or Ni) were 25.81, 50.15 and 76.34 mg g-1, respectively. Kinetics of methylene blue adsorption fitted the pseudo-second-order model. Overall, NiFe2O4@GO exhibited the highest adsorbent performance among the graphene-metal ferrites investigated, primarily because of its high specific surface area and presence of mesopores.


Assuntos
Grafite , Nanocompostos , Poluentes Químicos da Água , Adsorção , Corantes , Compostos Férricos , Cinética , Azul de Metileno , Águas Residuárias , Poluentes Químicos da Água/análise
9.
Dev Comp Immunol ; 111: 103746, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32445651

RESUMO

Interferon-induced proteins with tetratricopeptide repeats (IFITs) are involved in antiviral defense. Members of this protein family contain distinctive multiple structural motifs comprising tetratricopeptides that are tandemly arrayed or dispersed along the polypeptide. IFIT-encoding genes are upregulated by type I interferons (IFNs) and other stimuli. IFIT proteins inhibit virus replication by binding to and regulating the functions of cellular and viral RNA and proteins. In teleost fish, knowledge about genes and functions of IFITs is currently limited. In the present work, we describe an IFIT5 orthologue in Atlantic salmon (SsaIFIT5) with characteristic tetratricopeptide repeat motifs. We show here that the gene encoding SsaIFIT5 (SsaIfit5) was ubiquitously expressed in various salmon tissues, while bacterial and viral challenge of live fish and in vitro stimulation of cells with recombinant IFNs and pathogen mimics triggered its transcription. The profound expression in response to various immune stimulation could be ascribed to the identified IFN response elements and binding sites for various immune-relevant transcription factors in the putative promoter of the SsaIfit5 gene. Our results establish SsaIfit5 as an IFN-stimulated gene in A. salmon and strongly suggest a phylogenetically conserved role of the IFIT5 protein in antimicrobial responses in vertebrates.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Infecções por Alphavirus/imunologia , Alphavirus/fisiologia , Proteínas de Peixes/genética , Piscirickettsia/fisiologia , Infecções por Piscirickettsiaceae/imunologia , Salmo salar/imunologia , Animais , Células Cultivadas , Clonagem Molecular , Regulação da Expressão Gênica , Imunidade Inata , Interferons , Proteínas de Neoplasias/genética , Moléculas com Motivos Associados a Patógenos/imunologia , Filogenia , RNA Viral/imunologia , Transcriptoma
10.
Environ Sci Pollut Res Int ; 26(31): 32407-32419, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31606789

RESUMO

Diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug, has been detected in effluents of conventional wastewater treatment plants worldwide. The presence of this compound in various water resources even at very low concentrations poses a big threat both to human health and aquatic ecosystems. In this study, the removal of diclofenac from aqueous solution using Fe-Mn binary oxide (FMBO) adsorbents was investigated. FMBO adsorbents were prepared at varying Fe/Mn molar ratios (1:0, 3:1, and 1:1) through simultaneous oxidation and co-precipitation methods. Batch adsorption experiments were conducted to evaluate the effects of important parameters, such as initial DCF concentration, FMBO dosage, solution pH, and Fe/Mn molar ratio, on DCF removal. Acidic to neutral pH conditions were more favorable for DCF adsorption, while increasing initial DCF concentration and adsorbent dosage resulted in higher DCF removal efficiencies for the three oxides. Lower Fe/Mn molar ratio during FBMO synthesis favored higher DCF removals of up to 99% within a wide pH range. Optimization of operating parameters (initial DCF concentration, FMBO dosage, and solution pH) by Box-Behnken design resulted in up to 28.84 mg g-1 DCF removal for 3:1 FMBO. Freundlich isotherm best described the experimental data, indicating that adsorption occurred on heterogeneous adsorbent surface. Chemisorption was the rate-limiting step of the DCF removal, as best described by the pseudo-second-order kinetic model.


Assuntos
Diclofenaco/química , Ferro/química , Manganês/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Ecossistema , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Óxidos/química , Águas Residuárias
11.
Clin Nutr ; 38(1): 324-331, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29395370

RESUMO

BACKGROUND: The use of veno-venous extracorporeal membrane oxygenation (vv-ECMO) is increasing in adults with severe respiratory failure. Observational data suggest that there are significant challenges to providing adequate nutrition support for patients on vv-ECMO. We aimed to describe firstly the nutrition support practices in a large single-centre providing vv-ECMO to adults and secondly any association with clinical outcome. METHODS: We conducted a retrospective review of patients receiving vv-ECMO on the Intensive Care Unit (ICU) of a large London teaching hospital. Adult patients admitted to the ICU with severe respiratory failure between December 2010 and December 2015 were included. Daily energy and protein delivery were compared with estimated targets and reasons for feeding interruptions were collected from electronic medical records. Adequate feeding was defined as 80-110% of estimated targets. RESULTS: We analysed 203 eligible patients. Median duration of ICU stay was 21.0 (IQR, 15.0-33.0) days and vv-ECMO 10.0 (IQR, 7.0-16.0) days. Although median energy (89.8% (IQR, 80.5-96.0%)) and protein (84.7% (IQR, 74.0-96.7%)) delivery was adequate, underfeeding of either energy or protein occurred on nearly one third (28.3%) of nutrition support days. A higher admission severity of illness score was associated with inadequate protein delivery (p = 0.040). Patients with more severe organ dysfunction on the first day of vv-ECMO received inadequate energy (p = 0.026). The most common reasons for interrupted feeding were medical procedures (39.1%) followed by poor gastric motility (22.8%). CONCLUSION: Adequate energy and protein delivery during vv-ECMO is possible but underfeeding is still common, especially in those who are more severely ill or who have more severe organ dysfunction. Patients with inadequate energy or protein delivery did not differ in ICU and 6-month survival. Prospective studies investigating optimal feeding in this patient cohort are required.


Assuntos
Cuidados Críticos/métodos , Oxigenação por Membrana Extracorpórea/métodos , Apoio Nutricional/métodos , Adulto , Estudos de Coortes , Proteínas Alimentares/administração & dosagem , Ingestão de Energia/fisiologia , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Londres , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
J Environ Manage ; 223: 723-730, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29975900

RESUMO

In this study, the recovery of manganese (Mn) and iron (Fe) from groundwater treatment sludge through reductive acid leaching and hydroxide precipitation was investigated. Maximum leached Mn (100%) was obtained using sulfuric acid and hydrogen peroxide at 25 °C. Leached Mn and Fe decreased with the increase in the solid-liquid ratio. Leaching time had minimal effect on Mn and Fe leaching beyond 5 min, while agitation rate had minimal effect beyond 150 rpm. At 25 °C, the rate-limiting step of Mn leaching was diffusion through inert solid components of the sludge, composed mainly of insoluble sand particles. Fe leaching was governed by diffusion through the insoluble components of the sludge, including the unreacted manganese dioxide (MnO2). Maximum precipitation of Fe and separation from Mn in the leachate through addition of potassium hydroxide occurred at pH 4.0. The results demonstrated that reductive acid leaching and hydroxide precipitation is an effective means of recovering Mn and Fe from groundwater treatment sludge. The applicability of the recovered Mn for nickel ion removal from aqueous solution was also explored in the study. Highest nickel ion uptake by the MnO2 synthesized from the recovered Mn was at 111.67 mg g-1, even exceeding the adsorption capacities of previously studied nickel adsorbents.


Assuntos
Ferro/isolamento & purificação , Manganês/isolamento & purificação , Ácidos , Água Subterrânea , Esgotos
13.
PLoS One ; 10(7): e0132434, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26207374

RESUMO

MicroRNAs (miRNAs) are ~22 base pair-long non-coding RNAs which regulate gene expression in the cytoplasm of eukaryotic cells by binding to specific target regions in mRNAs to mediate transcriptional blocking or mRNA cleavage. Through their fundamental roles in cellular pathways, gene regulation mediated by miRNAs has been shown to be involved in almost all biological phenomena, including development, metabolism, cell cycle, tumor formation, and host-pathogen interactions. To address the latter in a primitive vertebrate host, we here used an array platform to analyze the miRNA response in rainbow trout (Oncorhynchus mykiss) following inoculation with the virulent fish rhabdovirus Viral hemorrhagic septicaemia virus. Two clustered miRNAs, miR-462 and miR-731 (herein referred to as miR-462 cluster), described only in teleost fishes, were found to be strongly upregulated, indicating their involvement in fish-virus interactions. We searched for homologues of the two teleost miRNAs in other vertebrate species and investigated whether findings related to ours have been reported for these homologues. Gene synteny analysis along with gene sequence conservation suggested that the teleost fish miR-462 and miR-731 had evolved from the ancestral miR-191 and miR-425 (herein called miR-191 cluster), respectively. Whereas the miR-462 cluster locus is found between two protein-coding genes (intergenic) in teleost fish genomes, the miR-191 cluster locus is found within an intron of a protein-coding gene (intragenic) in the human genome. Interferon (IFN)-inducible and immune-related promoter elements found upstream of the teleost miR-462 cluster locus suggested roles in immune responses to viral pathogens in fish, while in humans, the miR-191 cluster functionally associated with cell cycle regulation. Stimulation of fish cell cultures with the IFN inducer poly I:C accordingly upregulated the expression of miR-462 and miR-731, while no stimulatory effect on miR-191 and miR-425 expression was observed in human cell lines. Despite high sequence conservation, evolution has thus resulted in different regulation and presumably also different functional roles of these orthologous miRNA clusters in different vertebrate lineages.


Assuntos
Pontos de Checagem do Ciclo Celular/genética , MicroRNAs/genética , Novirhabdovirus/fisiologia , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/virologia , Animais , Sequência de Bases , Células Cultivadas , Evolução Molecular , Proteínas de Peixes/genética , Perfilação da Expressão Gênica/métodos , Interações Hospedeiro-Patógeno , Humanos , Fígado/citologia , Fígado/metabolismo , Fígado/virologia , MicroRNAs/classificação , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Filogenia , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Regulação para Cima
14.
Vaccine ; 33(28): 3215-22, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-25957662

RESUMO

Mechanisms that account for the high protective efficacy in teleost fish of a DNA vaccine expressing the glycoprotein (G) of Viral hemorrhagic septicemia virus (VHSV) are thought to involve early innate immune responses mediated by interferons (IFNs). Microribonucleic acids (miRNAs) are a diverse class of small (18-22 nucleotides) endogenous RNAs that potently mediate post-transcriptional silencing of a wide range of genes and are emerging as critical regulators of cellular processes, including immune responses. We have recently reported that miR-462 and miR-731 were strongly induced in rainbow trout infected with VHSV. In this study, we analyzed the expression of these miRNAs in fish following administration of the DNA vaccine and their potential functions. Quantitative RT-PCR analysis revealed the increased levels of miR-462, and miR-731 in the skeletal muscle tissue at the site of vaccine administration and in the liver of vaccinated fish relative to empty plasmid backbone-injected controls. The increased expression of these miRNAs in the skeletal muscle correlated with the increased levels of the type I interferon (IFN)-inducible gene Mx, type I IFN and IFN-γ genes at the vaccination site. Intramuscular injection of fish with either type I IFN or IFN-γ plasmid construct resulted in the upregulation of miR-462 and miR-731 at the site of injection, suggesting that the induction of these miRNAs is elicited by IFNs. To analyze the function of miR-462 and miR-731, specific silencing of these miRNAs using anti-miRNA oligonucleotides was conducted in poly I:C-treated rainbow trout fingerlings. Following VHSV challenge, anti-miRNA-injected fish had faster development of disease and higher mortalities than control fish, indicating that miR-462/731 may be involved in IFN-mediated protection conferred by poly I:C.


Assuntos
Septicemia Hemorrágica Viral/prevenção & controle , MicroRNAs/genética , Novirhabdovirus/imunologia , Oncorhynchus mykiss/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Animais , Expressão Gênica , Glicoproteínas/administração & dosagem , Glicoproteínas/química , Septicemia Hemorrágica Viral/imunologia , Imunidade Inata , Injeções Intramusculares , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Interferon gama/imunologia , MicroRNAs/imunologia , Plasmídeos , Poli I-C/administração & dosagem , Vacinas de DNA/administração & dosagem , Vacinas Virais/administração & dosagem
16.
PLoS One ; 6(12): e29430, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22216280

RESUMO

BACKGROUND: Dengue virus is transmitted by mosquitoes and has four serotypes. Cross-protection to other serotypes lasting for a few months is observed following infection with one serotype. There is evidence that low-affinity T and/or B cells from primary infections contribute to the severe syndromes often associated with secondary dengue infections. such pronounced immune-mediated enhancement suggests a dengue-specific pattern of immune cell activation. This study investigates the acute and early convalescent B cell response leading to the generation of cross-reactive and neutralizing antibodies following dengue infection. METHODOLOGY/PRINCIPAL FINDINGS: We assayed blood samples taken from dengue patients with primary or secondary infection during acute disease and convalescence and compared them to samples from patients presenting with non-dengue related fever. Dengue induced massive early plasmablast formation, which correlated with the appearance of polyclonal, cross-reactive IgG for both primary and secondary infection. Surprisingly, the contribution of IgG to the neutralizing titer 4-7 days after fever onset was more than 50% even after primary infection. CONCLUSIONS/SIGNIFICANCE: Poly-reactive and virus serotype cross-reactive IgG are an important component of the innate response in humans during both primary and secondary dengue infection, and "innate specificities" seem to constitute part of the adaptive response in dengue. While of potential importance for protection during secondary infection, cross-reactive B cells will also compete with highly neutralizing B cells and possibly interfere with their development.


Assuntos
Linfócitos B/imunologia , Vírus da Dengue/fisiologia , Dengue/imunologia , Imunoglobulina G/imunologia , Reações Cruzadas , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...