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BACKGROUND: Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra, which promotes a sustained inflammatory environment in the central nervous system. Regulatory T cells (Tregs) play an important role in the control of inflammation and might play a neuroprotective role. Indeed, a decrease in Treg number and function has been reported in PD. In this context, pramipexole, a dopaminergic receptor agonist used to treat PD symptoms, has been shown to increase peripheral levels of Treg cells and improve their suppressive function. The aim of this work was to determine the effect of pramipexole on immunoregulatory Treg cells and its possible neuroprotective effect on human dopaminergic neurons differentiated from human embryonic stem cells. METHODS: Treg cells were sorted from white blood cells of healthy human donors. Assays were performed with CD3/CD28-activated and non-activated Treg cells treated with pramipexole at concentrations of 2 or 200 ng/mL. These regulatory cells were co-cultured with in vitro-differentiated human dopaminergic neurons in a cytotoxicity assay with 6-hydroxydopamine (6-OHDA). The role of interleukin-10 (IL-10) was investigated by co-culturing activated IL-10-producing Treg cells with neurons. To further investigate the effect of treatment on Tregs, gene expression in pramipexole-treated, CD3/CD28-activated Treg cells was determined by Fluidigm analysis. RESULTS: Pramipexole-treated CD3/CD28-activated Treg cells showed significant protective effects on dopaminergic neurons when challenged with 6-OHDA. Pramipexole-treated activated Treg cells showed neuroprotective capacity through mechanisms involving IL-10 release and the activation of genes associated with regulation and neuroprotection. CONCLUSION: Anti-CD3/CD28-activated Treg cells protect dopaminergic neurons against 6-OHDA-induced damage. In addition, activated, IL-10-producing, pramipexole-treated Tregs also induced a neuroprotective effect, and the supernatants of these co-cultures promoted axonal growth. Pramipexole-treated, activated Tregs altered their gene expression in a concentration-dependent manner, and enhanced TGFß-related dopamine receptor regulation and immune-related pathways. These findings open new perspectives for the development of immunomodulatory therapies for the treatment of PD.
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Benzotiazóis , Neurônios Dopaminérgicos , Oxidopamina , Pramipexol , Linfócitos T Reguladores , Humanos , Pramipexol/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Oxidopamina/toxicidade , Benzotiazóis/farmacologia , Técnicas de Cocultura , Interleucina-10/metabolismo , Células Cultivadas , Fármacos Neuroprotetores/farmacologia , Agonistas de Dopamina/farmacologiaRESUMO
This is a case report of a young adult who died of COVID-19 twelve days after admission, with coronavirus nucleocapsid protein and lipofuscin found in the heart and kidney tissues, providing further evidence of the role of SARS-CoV-2 in cellular senescence.
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The disease burden of arthropod-borne infections is particularly high in low- and middle-income countries, where the availability of resources for surveillance and testing is limited. The lack of local infrastructure demands that biological samples be sent to central laboratories by refrigerated transport, which increases costs and the risk of sample degradation. Dried blood spot samples are an alternative for ensuring sample integrity during transportation and storage. They can be used for the detection of nucleic acids and proteins, such as antigens or antibodies. Here, we compared anti-chikungunya IgM, anti-dengue IgM, anti-dengue IgG, and anti-Zika IgG detection between paired serum and dried serum samples (DSSs); the agreement between results was found to be 90.6%, 94.1%, 85.9%, and 95.5%, respectively, indicating a strong correlation. Our results suggest that DSSs provide a reliable alternative for detection of specific antibodies in arthropod-borne infections.
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The PDZ (PSD95, Dlg and ZO-1) genes encode proteins that primarily function as scaffolds of diverse signaling pathways. To date, 153 PDZ genes have been identified in the human genome, most of which have multiple protein isoforms widely studied in epithelial and neural cells. However, their expression and function in immune cells have been poorly studied. Herein, we aimed to assess the transcriptional profiles of 83 PDZ genes in human macrophages (Mɸ) and dendritic cells (DCs) and changes in their relative expression during cell PRR stimulation. Significantly distinct PDZ gene transcriptional profiles were identified under different stimulation conditions. Furthermore, a distinct PDZ gene transcriptional signature was found in Mɸ and DCs under the same phagocytic stimuli. Notably, more than 40 PDZ genes had significant changes in expression, with potentially relevant functions in antigen-presenting cells (APCs). Given that several PDZ proteins are targeted by viral products, our results support that many of these proteins might be viral targets in APCs as part of evasion mechanisms. Our results suggest a distinct requirement for PDZ scaffolds in Mɸ and DCs signaling pathways activation. More assessments on the functions of PDZ proteins in APCs and their role in immune evasion mechanisms are needed.
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Evasão da Resposta Imune , Macrófagos , Células Dendríticas , Humanos , Macrófagos/metabolismo , Transdução de SinaisRESUMO
Murine cysticercosis by Taenia crassiceps is a model for human neurocysticercosis. Genetic and/or immune differences may underlie the higher susceptibility to infection in BALB/cAnN with respect to C57BL/6 mice. T regulatory cells (Tregs) could mediate the escape of T. crassiceps from the host immunity. This study is aimed to investigate the role of Tregs in T. crassiceps establishment in susceptible and non-susceptible mouse strains. Treg and effector cells were quantified in lymphoid organs before infection and 5, 30, 90, and 130 days post-infection. The proliferative response post-infection was characterized in vitro. The expression of regulatory and inflammatory molecules was assessed on days 5 and 30 post-infection. Depletion assays were performed to assess Treg functionality. Significantly higher Treg percentages were observed in BALB/cAnN mice, while increased percentages of activated CD127+ cells were found in C57BL/6 mice. The proliferative response was suppressed in susceptible mice, and Treg proliferation occurred only in susceptible mice. Treg-mediated suppression mechanisms may include IL-10 and TGFß secretion, granzyme- and perforin-mediated cytolysis, metabolic disruption, and cell-to-cell contact. Tregs are functional in BALB/cAnN mice. Therefore Tregs could be allowing parasite establishment and survival in susceptible mice but could play a homeostatic role in non-susceptible strains.
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Linfócitos T Reguladores , Taenia , Animais , Imunidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BLRESUMO
To date, mother-to-fetus transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the coronavirus disease 2019 (COVID-19) pandemic, remains controversial. Although placental COVID-19 infection has been documented in some cases during the second- and third-trimesters, no reports are available for the first trimester of pregnancy, and no SARS-CoV-2 protein has been found in fetal tissues. We studied the placenta and fetal organs from an early pregnancy miscarriage in a COVID-19 maternal infection by immunohistochemical, reverse transcription quantitative real-time polymerase chain reaction, immunofluorescence, and electron microscopy methods. SARS-CoV-2 nucleocapsid protein, viral RNA, and particles consistent with coronavirus were found in the placenta and fetal tissues, accompanied by RNA replication revealed by double-stranded RNA (dsRNA) positive immunostain. Prominent damage of the placenta and fetal organs were associated with a hyperinflammatory process identified by histological examination and immunohistochemistry. The findings provided in this study document that congenital SARS-CoV-2 infection is possible during the first trimester of pregnancy and that fetal organs, such as lung and kidney, are targets for coronavirus. The infection and multi-organic fetal inflammation produced by SARS-CoV-2 during early pregnancy should alert clinicians in the assessment and management of pregnant women for possible fetal consequences and adverse perinatal outcomes.
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COVID-19/transmissão , Transmissão Vertical de Doenças Infecciosas , Placenta/virologia , Complicações Infecciosas na Gravidez/virologia , SARS-CoV-2/metabolismo , Aborto Espontâneo/virologia , Adulto , COVID-19/patologia , Feminino , Feto/patologia , Feto/virologia , Humanos , Placenta/patologia , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Gestantes , RNA Viral/análiseRESUMO
BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease in the world. Various studies have suggested that the immune response plays a key role in this pathology. While a predominantly pro-inflammatory peripheral immune response has been reported in treated and untreated PD patients, the study of the role of the regulatory immune response has been restricted to regulatory T cells. Other immune suppressive populations have been described recently, but their role in PD is still unknown. This study was designed to analyze the pro and anti-inflammatory immune response in untreated PD patients, with emphasis on the regulatory response. METHODS: Thirty-two PD untreated patients and 20 healthy individuals were included in this study. Peripheral regulatory cells (CD4+Tregs, Bregs, CD8+Tregs, and tolerogenic dendritic cells), pro-inflammatory cells (Th1, Th2, and Th17 cells; active dendritic cells), and classical, intermediate, and non-classical monocytes were characterized by flow cytometry. Plasmatic levels of TNF-α, IFN-γ, IL-6, GM-CSF, IL-12p70, IL-4, IL-13, IL-17α, IL-1ß, IL-10, TGF-ß, and IL-35 were determined by ELISA. RESULTS: Decreased levels of suppressor Tregs, active Tregs, Tr1 cells, IL-10-producer CD8regs, and tolerogenic PD-L1+ dendritic cells were observed. With respect to the pro-inflammatory response, a decrease in IL-17-α and an increase in IL-13 levels were observed. CONCLUSION: A decrease in the levels of regulatory cell subpopulations in untreated PD patients is reported for the first time in this work. These results suggest that PD patients may exhibit a deficient suppression of the pro-inflammatory response, which could contribute to the pathophysiology of the disease.
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Linfócitos B Reguladores/imunologia , Células Dendríticas/imunologia , Doença de Parkinson/sangue , Linfócitos T Reguladores/imunologia , Idoso , Citocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/imunologiaRESUMO
OBJECTIVE: Parkinson's disease (PD) patients are usually treated with L-dopa and/or dopaminergic agonists, which act by binding five types of dopaminergic receptors (DRD1-DRD5). Peripheral immune cells are known to express dopamine receptors on their membrane surface, and therefore they could be directly affected by the treatment. Regulatory cells are the main modulators of inflammation, but it is not clear whether dopaminergic treatment could affect their functions. While only regulatory T cells (Tregs) have been proved to express dopamine receptors, it is not known whether other regulatory cells such as CD8regs, regulatory B cells (Bregs), tolerogenic dendritic cells, and intermediate monocytes also express them. METHODS: The expression of dopamine receptors in Tregs, CD8regs, Bregs, tolerogenic dendritic cells, and intermediate monocytes was herein evaluated. cDNA from 11 PD patients and 9 control subjects was obtained and analyzed. RESULTS: All regulatory cell populations expressed the genes coding for dopamine receptors, and this expression was further corroborated by flow cytometry. These findings may allow us to propose regulatory populations as possible targets for PD treatment. CONCLUSIONS: This study opens new paths to deepen our understanding on the effect of PD treatment on the cells of the regulatory immune response.
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Linfócitos B Reguladores/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Dendríticas/metabolismo , Monócitos/metabolismo , Doença de Parkinson/metabolismo , Receptores Dopaminérgicos/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/imunologiaRESUMO
We characterized natural vertical transmission of Zika virus in pools of Aedes aegypti larvae hatched from eggs collected in Jojutla, Morelos, Mexico. Of the 151 pools analyzed, 17 tested positive for Zika virus RNA; infectious Zika virus was successfully isolated from 1 of the larvae pools (31N) in C6/36 cells. Real-time quantitative PCR and indirect immunofluorescence assays confirmed the identity of the isolate, named Zika virus isolate 31N; plaque assays in Vero cells demonstrated the isolate's infectivity in a mammalian cell line. We obtained the complete genome of Zika virus isolate 31N by next-generation sequencing and identified 3 single-nucleotide variants specific to Zika virus isolate 31N using the meta-CATS tool. These results demonstrate the occurrence of natural vertical transmission of Zika virus in wild Ae. aegypti mosquitoes and suggest that this transmission mode could aid in the spread and maintenance of Zika virus in nature.
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Aedes/virologia , Mosquitos Vetores/virologia , Zika virus/fisiologia , Animais , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Microbiologia Ambiental , Genoma Viral , Humanos , Transmissão Vertical de Doenças Infecciosas , Larva , México/epidemiologia , Filogenia , Vigilância em Saúde Pública , Células Vero , Carga Viral , Ensaio de Placa Viral , Sequenciamento Completo do Genoma , Zika virus/classificação , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologiaRESUMO
BACKGROUND: During pregnancy, the Zika virus (ZIKV) replicates in the placenta and central nervous system (CNS) of infected fetuses; nevertheless, the ability of ZIKV to replicate in other fetal tissues has not been extensively characterized. METHODS: We researched whether dissemination of congenitally-acquired ZIKV outside the CNS exists by searching for the accumulation of the viral envelope protein, ZIKV ribonucleic acid (RNA), and infectious viral particles in different organs of a deceased newborn with Congenital Zika Syndrome. A real-time qualitative polymerase chain reaction (qPCR) was used to detect ZIKV RNA in the brain, thymus, lungs, kidneys, adrenal glands, spleen, liver, and small intestine. The same tissues were analyzed by indirect immunofluorescence and immunoperoxidase assays using the monoclonal antibody 4G2 to detect ZIKV envelope antigens. Isolation of infectious ZIKV in a cell culture was carried out using brain and kidney samples. RESULTS: A postmortem, virological analysis of multiple organs, such as the kidneys (epithelial cells in the renal tubules), lungs (bronchial epithelia), thymus (epithelial cells inside the Hassall's corpuscles), and brain (neurons, ependymal cells, and macrophages) revealed the presence of ZIKV RNA and envelope antigens. Other tissues of the deceased newborn tested positive by qPCR for Epstein-Barr virus and human herpesvirus 6, including the brain cortex (Epstein-Barr) and the thymus, kidneys, and adrenal glands (human herpesvirus 6). The kidneys were identified as a significant niche for viral replication, given that infectious particles were successfully isolated from renal tissues. CONCLUSIONS: Our findings demonstrate the ability of congenitally-acquired ZIKV to produce disseminated infections and the viral tropism towards epithelial cells.
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Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologia , Zika virus/genética , Antígenos Virais , Autopsia , Biópsia , Coinfecção , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Transmissão Vertical de Doenças Infecciosas , Nefropatias/patologia , Nefropatias/virologia , México/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Vigilância em Saúde Pública , RNA Viral , Adulto Jovem , Zika virus/imunologia , Zika virus/ultraestrutura , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissãoRESUMO
This study shows the relative quantification of HSV-2 by qPCR, using the MIQE Guidelines. The reaction efficiency was evaluated, and the relative quantification used the R = 2-ΔCq method. The relative quantification of HSV-2 was conducted with anal and genital samples from men who have sex with men (MSM), living with HIV. The presence of a single amplification product was validated with a dissociation curves profile and the determination of the melting temperature. The limit of detection for ß-globin was determined as 3.3 × 10-5 ng/µL, and for HSV-2 at 6.0 × 10-6 ng/µL. The efficiency for ß-globin was 100.2% and for HSV-2 was 106.8%. From 336 MSM, 2.1% and 3.9% individuals presented anal or genital HSV-2 shedding, respectively. The HSV-2 viral load was 9.2 RU, individuals with fewer CD4+ presented higher HSV-2 viral load. The qPCR method is reproducible and has optimal reaction efficiency.
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Canal Anal/virologia , Genitália Masculina/virologia , Infecções por HIV/complicações , Herpes Genital/virologia , Herpesvirus Humano 2/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Eliminação de Partículas Virais , Adulto , Herpesvirus Humano 2/genética , Homossexualidade Masculina , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral/métodosRESUMO
Antibodies to Zika virus (ZIKV) can be protective. To examine the antibody response in individuals who develop high titers of anti-ZIKV antibodies, we screened cohorts in Brazil and Mexico for ZIKV envelope domain III (ZEDIII) binding and neutralization. We find that serologic reactivity to dengue 1 virus (DENV1) EDIII before ZIKV exposure is associated with increased ZIKV neutralizing titers after exposure. Antibody cloning shows that donors with high ZIKV neutralizing antibody titers have expanded clones of memory B cells that express the same immunoglobulin VH3-23/VK1-5 genes. These recurring antibodies cross-react with DENV1, but not other flaviviruses, neutralize both DENV1 and ZIKV, and protect mice against ZIKV challenge. Structural analyses reveal the mechanism of recognition of the ZEDIII lateral ridge by VH3-23/VK1-5 antibodies. Serologic testing shows that antibodies to this region correlate with serum neutralizing activity to ZIKV. Thus, high neutralizing responses to ZIKV are associated with pre-existing reactivity to DENV1 in humans.
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Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Infecção por Zika virus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Brasil , Feminino , Humanos , Memória Imunológica , Leucócitos Mononucleares/imunologia , Masculino , México , Camundongos , Infecção por Zika virus/sangueRESUMO
Zika virus (ZIKV) is an emerging arthropod-borne flavivirus associated with severe congenital malformations and neurological complications. Although the ZIKV genome is well characterized, there is limited information regarding changes after cell isolation and culture adaptation. We isolated, and passaged in Vero cells, ZIKV from the serum of a symptomatic male patient and compared the viral genomes before and after culture. Single nucleotide polymorphisms were characteristic among serum-circulating genomes, while such diversity decreased after cell culture.
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BACKGROUND AND AIMS: Despite increase in survival of HIV patients due to highly active antiretroviral therapy (HAART), non-infectious complications are still prevalent such as presentation of lung vasculopathy, even in asymptomatic patients. Endothelin-1 (ET-1) is a potent vasoconstrictor that causes pulmonary vasculopathy. Participation of this protein in the pulmonary circulation in HIV patients has not been elucidated. In this work we studied the presence and expression of ET-1 in pulmonary complex vascular lesions associated with human immunodeficiency virus (PCVL/HIV). METHODS: We used immunohistochemistry and immunochemiluminescence (imagej) to determine the different degrees of expression of ET-1 in PCVL/HIV in comparison with non-PCVL/HIV. Reagents used were anti-endothelin-1 and an automated system. All data are presented as mean and standard deviation (SD). Differences were analyzed with one-way ANOVA; p < 0.05 was accepted as statistically significant. RESULTS: Lung tissues from 56 patients who died from complications of HIV pulmonary infection and with PCVL were studied. Histological evidence of pulmonary vasculopathy was shown as different types (proliferative, obliterative and plexiform). A statistically significant increase in ET-1 expression was observed in all PCVL/HIV tissue samples and is associated directly with different grades of severity of endothelial dysfunction. CONCLUSIONS: ET-1 has a relevant role in the pathogenesis of pulmonary vasculopathy in acquired immunodeficiency syndrome (AIDS) patients. It is necessary to determine in the future the participation of ET-1 and other mechanisms involved in PCVL/HIV.
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Síndrome da Imunodeficiência Adquirida/complicações , Endotelina-1/biossíntese , Pneumopatias/metabolismo , Doenças Vasculares/metabolismo , Adulto , Feminino , Humanos , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Pulmão/patologia , Pneumopatias/etiologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/patologia , Circulação Pulmonar , Doenças Vasculares/etiologia , Doenças Vasculares/fisiopatologia , Adulto JovemRESUMO
The non-structural protein 1 (NS1) of influenza A virus (IAV), coded by its third most diverse gene, interacts with multiple molecules within infected cells. NS1 is involved in host immune response regulation and is a potential contributor to the virus host range. Early phylogenetic analyses using 50 sequences led to the classification of NS1 gene variants into groups (alleles) A and B. We reanalyzed NS1 diversity using 14,716 complete NS IAV sequences, downloaded from public databases, without host bias. Removal of sequence redundancy and further structured clustering at 96.8% amino acid similarity produced 415 clusters that enhanced our capability to detect distinct subgroups and lineages, which were assigned a numerical nomenclature. Maximum likelihood phylogenetic reconstruction using RNA sequences indicated the previously identified deep branching separating group A from group B, with five distinct subgroups within A as well as two and five lineages within the A4 and A5 subgroups, respectively. Our classification model proposes that sequence patterns in thirteen amino acid positions are sufficient to fit >99.9% of all currently available NS1 sequences into the A subgroups/lineages or the B group. This classification reduces host and virus bias through the prioritization of NS1 RNA phylogenetics over host or virus phenetics. We found significant sequence conservation within the subgroups and lineages with characteristic patterns of functional motifs, such as the differential binding of CPSF30 and crk/crkL or the availability of a C-terminal PDZ-binding motif. To understand selection pressures and evolution acting on NS1, it is necessary to organize the available data. This updated classification may help to clarify and organize the study of NS1 interactions and pathogenic differences and allow the drawing of further functional inferences on sequences in each group, subgroup and lineage rather than on a strain-by-strain basis.
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Sequência Conservada , Filogenia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Aminoácidos/metabolismo , Sequência de Bases , Análise por Conglomerados , Funções Verossimilhança , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Domínios PDZ , Ligação Proteica , Proteínas Proto-Oncogênicas c-crk/metabolismo , RNA Viral/genética , SumoilaçãoRESUMO
BACKGROUND: Pandemic type A (H1N1) influenza arose in early 2009, probably in Mexico and the United States, and reappeared in North America in September for seven more months. An amino acid substitution in the hemagglutinin (HA), D222G, has been reported in a significant proportion of patients with a severe and fatal outcome. We studied the prevalence of HA222 substitutions in patients in Mexico during the second wave and its association with clinical outcome and pathogenicity in a mouse model. METHODS: The nucleotide sequences of hemagglutinin (HA) from viruses collected from 77 patients were determined including 50 severe and fatal cases and 27 ambulatory cases. Deep sequencing was done on 5 samples from severe or fatal cases in order to determine the quasispecies proportion. Weight loss and mortality due to infection with cultured influenza viruses were analyzed in a mouse model. RESULTS: Viruses from 14 out of 50 hospitalized patients (28%) had a non aspartic acid residue at the HA 222 position (nD222), while all 27 ambulatory patients had D222 (p=0.0014). G222 was detected as sole species or in coexistence with N222 and D222 in 12 patients with severe disease including 8 who died. N222 in coexistence with D222 was detected in 1 patient who died and co-occurrence of A222 and V222, together with D222, was detected in another patient who died. The patients with a nD222 residue had higher mortality (71.4%), compared to the group with only D222 (22.2%, p=0.0008). Four of the 14 viruses from hospitalized patients were cultured and intranasally infected into mice. Two viruses with G222 were lethal while a third virus, with G222, caused only mild illness in mice similar to the fourth virus that contained D222. CONCLUSIONS: We confirm the elevated incidence of HA222 (H1N1)pdm09 variants in severe disease and mortality. Both clinical and mouse infection data support the idea that nD222 mutations contribute to increased severity of disease but additional determinants in disease outcome may be present.
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Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/mortalidade , Influenza Humana/patologia , Índice de Gravidade de Doença , Fatores de Virulência/genética , Adulto , Animais , Sequência de Bases , Peso Corporal , Modelos Animais de Doenças , Feminino , Histocitoquímica , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Pulmão/patologia , Masculino , México/epidemiologia , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , RNA Viral/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de SobrevidaRESUMO
BACKGROUND: Influenza viruses pose a threat to human health because of their potential to cause global disease. Between mid March and mid April a pandemic influenza A virus emerged in Mexico. This report details 202 cases of infection of humans with the 2009 influenza A virus (H1N1)v which occurred in Mexico City as well as the spread of the virus throughout the entire country. METHODOLOGY AND FINDINGS: From May 1st to May 5th nasopharyngeal swabs, derived from 751 patients, were collected at 220 outpatient clinics and 28 hospitals distributed throughout Mexico City. Analysis of samples using real time RT-PCR revealed that 202 patients out of the 751 subjects (26.9%) were confirmed to be infected with the new virus. All confirmed cases of human infection with the strain influenza (H1N1)v suffered respiratory symptoms. The greatest number of confirmed cases during the outbreak of the 2009 influenza A (H1N1)v were seen in neighbourhoods on the northeast side of Mexico City including Iztapalapa, Gustavo A. Madero, Iztacalco, and Tlahuac which are the most populated areas in Mexico City. Using these data, together with data reported by the Mexican Secretariat of Health (MSH) to date, we plot the course of influenza (H1N1)v activity throughout Mexico. CONCLUSIONS: Our data, which is backed up by MSH data, show that the greatest numbers of the 2009 influenza A (H1N1) cases were seen in the most populated areas. We speculate on conditions in Mexico which may have sparked this flu pandemic, the first in 41 years. We accept the hypothesis that high population density and a mass gathering which took in Iztapalapa contributed to the rapid spread of the disease which developed in three peaks of activity throughout the Country.
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Surtos de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , México/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
A cell fusion assay using fusion-from-without (FFWO) recombinant adenoviruses (RAds) and specific antibody showed a role in fusion modulation for glycoprotein gO, the recently identified third component of the gH/gL gCIII complex of human cytomegalovirus (HCMV). As in HCMV, RAd gO expressed multiple glycosylated species with a mature product of 125 kDa. Coexpression with gH/gL RAds showed gCIII reconstitution in the absence of other HCMV products and stabilisation by intermolecular disulfide bonds. Properties of HCMV clinical isolate, Pt, also implicated gO in cell spread. Compared to laboratory strain AD169, Pt was resistant to gH antibody plaque inhibition, but mature gH was identical. However, the gO sequences were highly divergent (20%), with further variation in laboratory strain Towne gO (34%). Thus, gO forms gCIII with gH/gL, performs in cell fusion, and is a newly identified HCMV hypervariable locus which may influence gCIII's function in mediating infection.