RESUMO
To catalyze severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research, including development of novel interventive and preventive strategies, the progression of disease was characterized in a robust coronavirus disease 2019 (COVID-19) animal model. In this model, male and female golden Syrian hamsters were inoculated intranasally with SARS-CoV-2 USA-WA1/2020. Groups of inoculated and mock-inoculated uninfected control animals were euthanized at 2, 4, 7, 14, and 28 days after inoculation to track multiple clinical, pathology, virology, and immunology outcomes. SARS-CoV-2-inoculated animals consistently lost body weight during the first week of infection, had higher lung weights at terminal time points, and developed lung consolidation per histopathology and quantitative image analysis measurements. High levels of infectious virus and viral RNA were reliably present in the respiratory tract at days 2 and 4 after inoculation, corresponding with widespread necrosis and inflammation. At day 7, when the presence of infectious virus was rare, interstitial and alveolar macrophage infiltrates and marked reparative epithelial responses (type II hyperplasia) dominated in the lung. These lesions resolved over time, with only residual epithelial repair evident by day 28 after inoculation. The use of quantitative approaches to measure cellular and morphologic alterations in the lung provides valuable outcome measures for developing therapeutic and preventive interventions for COVID-19 using the hamster COVID-19 model.
Assuntos
COVID-19/patologia , Animais , COVID-19/virologia , Cricetinae , Modelos Animais de Doenças , Feminino , Pulmão/patologia , Masculino , Mesocricetus , SARS-CoV-2RESUMO
Staphylococcus aureus nasal carriage is transient in most humans and usually benign, but dissemination of S. aureus to extranasal sites causes the majority of clinical infections, and S. aureus is a major cause of serious infections in the United States. A better understanding of innate nasal decolonization mechanisms is urgently needed, as are relevant models for studying S. aureus clearance. Here, we screened a population of healthy smokers for nasal S. aureus carriage and compared the participants' abilities to clear experimentally applied nasal S. aureus before and after completion of a smoking cessation program. We determined that cigarette smoking increases the mean nasal S. aureus load (2.6 × 104 CFU/swab) compared to the load observed in healthy nonsmokers (1.7 × 103 CFU/swab) and might increase the rate of S. aureus nasal carriage in otherwise-healthy adults: 22 of 99 smokers carried S. aureus at the screening visit, while only 4 of 30 nonsmokers screened positive during the same time period. Only 6 of 19 experimental inoculation studies in active smokers resulted in S. aureus clearance within the month of follow-up, while in the cessation group, 6 of 9 subjects cleared nasal S. aureus and carriage duration averaged 21 ± 4 days. Smoking cessation associated with enhanced expression of S. aureus-associated interleukin-1ß (IL-1ß) and granulocyte colony-stimulating factor (G-CSF) in nasal fluids. Participants who failed to clear S. aureus exhibited a higher nasal S. aureus load and elevated nasal interleukin-1 receptor antagonist (IL-1RA) expression at the preexperiment study visits. We conclude that smokers exhibit higher S. aureus loads than nonsmokers and that innate immune pathways, including G-CSF expression and signaling through the IL-1 axis, are important mediators of nasal S. aureus clearance.
Assuntos
Imunidade Inata , Mucosa Nasal/imunologia , Mucosa Nasal/microbiologia , Abandono do Hábito de Fumar , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Adulto , Carga Bacteriana , Portador Sadio/imunologia , Portador Sadio/microbiologia , Feminino , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/metabolismo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/genética , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/metabolismo , Adulto JovemRESUMO
UNLABELLED: The "shock and kill" model of human immunodeficiency virus type 1 (HIV-1) eradication involves the induction of transcription of HIV-1 genes in latently infected CD4(+) T cells, followed by the elimination of these infected CD4(+) T cells by CD8(+) T cells or other effector cells. CD8(+) T cells may also be needed to control the spread of new infection if residual infected cells are present at the time combination antiretroviral therapy (cART) is discontinued. In order to determine the time frame needed for CD8(+) T cells to effectively prevent the spread of HIV-1 infection, we examined the kinetics of HIV transcription and virus release in latently infected cells reactivated ex vivo. Isolated resting, primary CD4(+) T cells from HIV-positive (HIV+) subjects on suppressive regimens were found to upregulate cell-associated HIV-1 mRNA within 1 h of stimulation and produce extracellular virus as early as 6 h poststimulation. In spite of the rapid kinetics of virus production, we show that CD8(+) T cells from 2 out of 4 viremic controllers were capable of effectively eliminating reactivated autologous CD4(+) cells that upregulate cell-associated HIV-1 mRNA. The results have implications for devising strategies to prevent rebound viremia due to reactivation of rare latently infected cells that persist after potentially curative therapy. IMPORTANCE: A prominent HIV-1 cure strategy termed "shock and kill" involves the induction of HIV-1 transcription in latently infected CD4(+) T cells with the goal of elimination of these cells by either the cytotoxic T lymphocyte response or other immune cell subsets. However, the cytotoxic T cell response may also be required after curative treatment if residual latently infected cells remain. The kinetics of HIV-1 reactivation indicate rapid upregulation of cell-associated HIV-1 mRNA and a 5-h window between transcription and virus release. Thus, HIV-specific CD8(+) T cell responses likely have a very short time frame to eliminate residual latently infected CD4(+) T cells that become reactivated after discontinuation of antiretroviral therapy following potentially curative treatment strategies.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Modelos Imunológicos , Ativação Viral/imunologia , Latência Viral/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Feminino , Infecções por HIV/patologia , Humanos , Masculino , Liberação de Vírus/imunologiaRESUMO
In the fourth decade of the HIV epidemic, the relationship between host immunity and HIV central nervous system (CNS) disease remains incompletely understood. Using a simian immunodeficiency virus (SIV)/macaque model, we examined CNS outcomes in pigtailed macaques expressing the MHC class I allele Mane-A1*084:01 which confers resistance to SIV-induced CNS disease and induces the prototypic viral escape mutation Gag K165R. Insertion of gag K165R into the neurovirulent clone SIV/17E-Fr reduced viral replication in vitro compared to SIV/17E-Fr. We also found lower cerebrospinal fluid (CSF), but not plasma, viral loads in macaques inoculated with SIV/17E-Fr K165R versus those inoculated with wildtype. Although escape mutation K165R was genotypically stable in plasma, it rapidly reverted to wildtype Gag KP9 in both CSF and in microglia cultures. We induced robust Gag KP9-specific CTL tetramer responses by vaccinating Mane-A*084:01-positive pigtailed macaques with a Gag KP9 virus-like particle (VLP) vaccine. Upon SIV/17E-Fr challenge, vaccinated animals had lower SIV RNA in CSF compared to unvaccinated controls, but showed no difference in plasma viral loads. These data clearly demonstrate that viral fitness in the CNS is distinct from the periphery and underscores the necessity of understanding the consequences of viral escape in CNS disease with the advent of new therapeutic vaccination strategies.
Assuntos
Produtos do Gene gag/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , RNA Viral/líquido cefalorraquidiano , Vacinas contra a SAIDS/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Alelos , Animais , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/virologia , Expressão Gênica , Produtos do Gene gag/genética , Antígenos de Histocompatibilidade Classe I/genética , Evasão da Resposta Imune/genética , Macaca nemestrina/imunologia , Macaca nemestrina/virologia , Masculino , Microglia/imunologia , Microglia/virologia , Mutação , Cultura Primária de Células , RNA Viral/sangue , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Vacinação , Carga Viral/imunologia , Replicação Viral/imunologiaRESUMO
Immune pressure exerted by MHC class I-restricted cytotoxic T cells drives the development of viral escape mutations, thereby regulating HIV disease progression. Nonetheless, the relationship between host immunity and HIV central nervous system (CNS) disease remains poorly understood. The simian immunodeficiency virus (SIV) macaque model recapitulates key features of HIV infection including development of AIDS and CNS disease. To investigate cell-mediated immunity regulating SIV CNS disease progression, we compared the incidence of SIV encephalitis and the influence of MHC class I allele expression on the development of CNS disease in rhesus macaques (Macaca mulatta) versus pigtailed macaques (Macaca nemestrina). After inoculation with the immunosuppressive swarm SIV/DeltaB670 and the neurovirulent molecular clone SIV/17E-Fr, pigtailed macaques progressed more rapidly to AIDS, had higher plasma and cerebrospinal fluid (CSF) viral loads, and were more likely to progress to SIV-associated encephalitis (SIVE) compared to rhesus macaques. In addition, MHC class I alleles were neuroprotective in both species (Mamu-A*001 in rhesus macaques and Mane-A1*084:01:01 in pigtailed macaques); animals expressing these alleles were less likely to develop SIV encephalitis and correspondingly had lower viral replication in the brain. Species-specific differences in susceptibility to SIV disease demonstrated that cell mediated immune responses are critical to SIV CNS disease progression.
Assuntos
Suscetibilidade a Doenças/imunologia , Macaca mulatta/virologia , Macaca nemestrina/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Complexo AIDS Demência/imunologia , Animais , Progressão da Doença , Antígenos de Histocompatibilidade Classe I/imunologia , Macaca mulatta/imunologia , Macaca nemestrina/imunologia , Vírus da Imunodeficiência SímiaRESUMO
Activation of the kynurenine pathway (KP) of tryptophan catabolism likely contributes to HIV-associated neurological disorders. However, KP activation in brain tissue during HIV infection has been understudied, and the effect of combination antiretroviral therapy (cART) on KP induction in the brain is unknown. To examine these questions, tryptophan, kynurenine, 3-hydroxykynurenine, quinolinic acid, and serotonin levels were measured longitudinally during SIV infection in the striatum and CSF from untreated and cART-treated pigtailed macaques. Messenger RNA (mRNA) levels of KP enzymes also were measured in the striatum. In untreated macaques, elevations in KP metabolites coincided with transcriptional induction of upstream enzymes in the KP. Striatal KP induction was also temporally associated-but did not directly correlate-with serotonin losses in the brain. CSF quinolinic acid/tryptophan ratios were found to be the earliest predictor of neurological disease in untreated SIV-infected macaques, outperforming other KP metabolites as well as the putative biomarkers interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1). Finally, cART did not restore KP metabolites to control levels in the striatum despite the control of the virus, though CSF metabolite levels were normalized in most animals. Overall, these results demonstrate that cerebral KP activation is only partially resolved with cART and that CSF QUIN/TRP ratios are an early, predictive biomarker of CNS disease.
Assuntos
Encéfalo/metabolismo , Cinurenina/metabolismo , Ácido Quinolínico/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Triptofano/metabolismo , Animais , Antirretrovirais/farmacologia , Encéfalo/virologia , Ensaio de Imunoadsorção Enzimática , Cromatografia Gasosa-Espectrometria de Massas , Imuno-Histoquímica , Macaca , Reação em Cadeia da PolimeraseRESUMO
BACKGROUND: This study examines factors related to general health and health behavior, including smoking, that may be associated with binge drinking, drinking "at risk," and potential for alcohol use disorder among young adults of Mexican ancestry. METHODS: A total of 2191 young adult emergency department (ED) patients (18-30 years) of Mexican ancestry in a public hospital proximate to the US-Mexico border completed health surveys while they were waiting to be treated, including questions on general health, drinking, smoking, and drug use. RESULTS: Thirty-seven percent of the study participants reported binge drinking, 38% were "at-risk" alcohol users (above National Institute on Alcohol Abuse and Alcoholism guidelines), and 22% were Rapid Alcohol Problem Screen (RAPS) positive (indicating potential for alcohol use disorder). Smoking was reported by 31%, marijuana use by 16%, and other drug use by 9%. Multiple variable models revealed that smoking was the strongest factor associated with binge drinking. Those who smoked were 3.1 (P < .0001) times more likely to binge drink. Other factors independently associated with binge drinking were age 22-25 years (odds ratio [OR] = 1.5, P = .003), male gender (OR = 1.5, P = .0001), and ED visit for injury (OR = 1.4, P = .007). CONCLUSIONS: There is a strong association of smoking and binge drinking. Study findings suggest that brief interventions designed to reduce preventable health risks for young Hispanics should include discussion of both binge drinking and smoking behaviors.
Assuntos
Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Fumar Maconha/epidemiologia , Americanos Mexicanos/psicologia , Fumar/epidemiologia , Adolescente , Comportamento do Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino , México/etnologia , Fatores de Risco , Fatores Sexuais , Texas/epidemiologia , Adulto JovemRESUMO
Following infection with Human immunodeficiency virus 1 (HIV-1) there is a remarkable variation in virus replication and disease progression. Both host and viral factors have been implicated in the observed differences in disease status. Here, we focus on understanding the contribution of HIV-1 viral protein R (Vpr) by evaluating the disease-associated Vpr polymorphism and its biological functions from HIV-1 positive rapid progressor (RP) and long-term nonprogressor (LTNP) subjects. Results presented here show distinct variation in phenotypes of Vpr alleles from LTNP and RP subjects. Most notably, the polymorphism of Vpr at R36W and L68M associated with RP shows higher levels of oligomerization, and increased virus replication, whereas R77Q exhibits poor replication kinetics. Interestingly, we did not observe correlation with cell cycle arrest function. Together these results indicate that polymorphisms in Vpr in part may contribute to altered virus replication kinetics leading to the observed differences in disease progression in LTNP and RP groups.
Assuntos
Infecções por HIV/virologia , HIV-1/genética , Polimorfismo Genético , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/genética , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/metabolismo , Progressão da Doença , Pontos de Checagem da Fase G2 do Ciclo Celular , Infecções por HIV/patologia , Infecções por HIV/fisiopatologia , HIV-1/classificação , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Filogenia , Replicação ViralRESUMO
Effective combined antiretroviral therapy (cART) in HIV-infected patients has made HIV a treatable infection; however, debilitating HIV-associated neurocognitive disorders (HAND) can still affect approximately 50% of HIV-infected individuals even under cART. While cART has greatly reduced the prevalence of the most severe form of HAND, milder forms have increased in prevalence, leaving the total proportion of HIV-infected individuals suffering from HAND relatively unchanged. In this study, an in vitro drug screen identified fluconazole and paroxetine as protective compounds against HIV gp120 and Tat neurotoxicity. Using an accelerated, consistent SIV/macaque model of HIV-associated CNS disease, we tested the in vivo neuroprotective capabilities of combination fluconazole/paroxetine (FluPar) treatment. FluPar treatment protected macaques from SIV-induced neurodegeneration, as measured by neurofilament light chain in the CSF, APP accumulation in axons, and CaMKIIα in the frontal cortex, but did not significantly reduce markers of neuroinflammation or plasma or CNS viral loads. Since HIV and SIV neurodegeneration is often attributed to accompanying neuroinflammation, this study provides proof of concept that neuroprotection can be achieved even in the face of ongoing neuroinflammation and viral replication.
Assuntos
Fluconazol/farmacologia , Neurônios/efeitos dos fármacos , Nootrópicos/farmacologia , Paroxetina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Complexo AIDS Demência/tratamento farmacológico , Complexo AIDS Demência/fisiopatologia , Complexo AIDS Demência/virologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/fisiopatologia , Síndrome da Imunodeficiência Adquirida/virologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Humanos , Macaca nemestrina , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Proteínas de Neurofilamentos/genética , Neurônios/patologia , Neurônios/virologia , Cultura Primária de Células , Ratos , Síndrome de Imunodeficiência Adquirida dos Símios/líquido cefalorraquidiano , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/fisiologia , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
BACKGROUND: The American College of Cardiology/American Society of Nuclear Cardiology published revised appropriate use criteria (AUC) for SPECT MPI in 2009. We assessed adherence to these guidelines and factors associated with inappropriate utilization at the University Medical Center. METHODS: The AUC was applied retrospectively to 420 SPECT MPI studies. Two-sample t test, Fisher's exact test, and multivariable logistic regression models were used for analysis. RESULTS: There were 322 appropriate (86%) and 54 (14%) inappropriate studies. The odds of having an inappropriate test increased with younger age (P < .001) and female gender (P < .001). Subjects with diabetes (P = .007) and chest pain (P < .001) were less likely to have an inappropriate test. Academic outpatients were three times more likely to have an inappropriate study (P = .123), while community PCPs were 5.6 times (P = .011) and community cardiologists eight times more likely to order inappropriate tests (P = .031). CONCLUSIONS: Inappropriate SPECT MPI in low risk younger women is an important issue on the USA-Mexico border. Initiatives to reduce inappropriate SPECT MPI should focus on a few indications and evaluation of cardiovascular symptoms in younger age women in outpatient/community practices.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Fidelidade a Diretrizes/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/normas , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/normas , Procedimentos Desnecessários/estatística & dados numéricos , Distribuição por Idade , Cardiologia/normas , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etnologia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Área Carente de Assistência Médica , México/epidemiologia , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Padrões de Prática Médica/estatística & dados numéricos , Prevalência , Distribuição por Sexo , Estados Unidos/epidemiologia , Procedimentos Desnecessários/normas , Revisão da Utilização de Recursos de SaúdeRESUMO
Buprenorphine hydrochloride (Bup-HCl) is a common injectable opioid analgesic. In ferrets, Bup-HCl must be administered every 8 to 12 h to maintain clinical efficacy. Extended-release analgesics offer multiple advantages, including reduced handling and injection frequency, improved compliance, and increased protection from end-of-dose failure. Although efficacy of extended-release buprenorphine formulations has been demonstrated in other species, their use in the domestic ferret has not been investigated. In this study, we evaluated the pharmacokinetics of a compounded polymeric formulation of buprenorphine (Bup-ER) and a pharmaceutical-grade, FDA-indexed liposomal suspension (Bup-XR). Two doses each of Bup-ER (0.12 and 0.2 mg/kg) and Bup-XR (0.2 and 0.6 mg/kg SC) were administered to young adult female ferrets and plasma concentrations were measured between 0 and 96 h (n = 4 animals per timepoint). All doses of both drugs achieved therapeutic plasma levels by 30 min. Furthermore, high-dose Bup-XR maintained therapeutic levels for 72 h, followed by high-dose Bup-ER (less than 48 h), low-dose Bup-XR (24 h), and low-dose Bup-ER (less than 24 h). In this study, we also developed a pain scoring system and utilized this to compare analgesic efficacy between single high-dose Bup-XR (0.6 mg/kg SC) and a standard postoperative course of Bup-HCl (0.02 mg/kg SC every 10 to 12 h for 8 doses) after ovariohysterectomy. Ferrets receiving Bup-XR had significantly lower respiratory rate and posture scores in the first 24 h postoperatively than did those that received Bup-HCl and were less likely to react to palpation of the surgical incision. Of note, ferrets that received high-dose Bup-ER had a significantly higher incidence of injection site reactions than ferrets that received Bup-HCl (P = 0.0137). This study demonstrates that a single dose of Bup-XR (0.6 mg/kg SC) is a safe and effective analgesic in female ferrets, with a duration of action up to 72 h and minimal side effects, offering a refinement to analgesia in this species.
RESUMO
BACKGROUND: Host cell microRNAs (miRNAs) have been shown to regulate the expression of both cellular and viral RNAs, in particular impacting both Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV). To investigate the role of miRNAs in regulating replication of the simian immunodeficiency virus (SIV) in macrophage lineage cells, we used primary macrophages to study targeting of SIV RNA by miRNAs. We examined whether specific host miRNAs directly target SIV RNA early in infection and might be induced via type I interferon pathways. RESULTS: miRNA target prediction programs identified miRNA binding sites within SIV RNA. Predicted binding sites for miRs-29a, -29b, -9 and -146a were identified in the SIV Nef/U3 and R regions, and all four miRNAs decreased virus production and viral RNA expression in primary macrophages. To determine whether levels of these miRNAs were affected by SIV infection, IFNß or TNFα treatments, miRNA RT-qPCR assays measured miRNA levels after infection or treatment of macrophages. SIV RNA levels as well as virus production was downregulated by direct targeting of the SIV Nef/U3 and R regions by four miRNAs. miRs-29a, -29b, -9 and -146a were induced in primary macrophages after SIV infection. Each of these miRNAs was regulated by innate immune signaling through TNFα and/or the type I IFN, IFNß. CONCLUSIONS: The effects on miRNAs caused by HIV/SIV infection are illustrated by changes in their cellular expression throughout the course of disease, and in different patient populations. Our data demonstrate that levels of primary transcripts and mature miRs-29a, -29b, -9 and -146a are modulated by SIV infection. We show that the SIV 3' UTR contains functional miRNA response elements (MREs) for all four miRNAs. Notably, these miRNAs regulate virus production and viral RNA levels in macrophages, the primary cells infected in the CNS that drive inflammation leading to HIV-associated neurocognitive disorders. This report may aid in identification miRNAs that target viral RNAs and HIV/SIV specifically, as well as in identification of miRNAs that may be targets of new therapies to treat HIV.
Assuntos
Macrófagos/imunologia , Macrófagos/virologia , MicroRNAs/metabolismo , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Replicação Viral , Regiões 3' não Traduzidas , Animais , Células Cultivadas , Regulação para Baixo , Macaca , MicroRNAs/genética , RNA Viral/genética , Vírus da Imunodeficiência Símia/genéticaRESUMO
One major activity of chemokines is the recruitment of immune cells to sites of infection and inflammation. CD4(+) Th1 cells play critical roles in host defense against pathogens and in the pathogenesis of many immune-mediated diseases. It was reported that epigallocatechin-3-gallate (EGCG) exhibits anti-inflammatory properties, but the mechanisms have not been completely defined. In this study, we found that EGCG markedly decreased recruitment of murine OVA-specific Th1 cells and other inflammatory cells into the airways in a Th1 adoptive-transfer mouse model. In vitro analysis revealed that EGCG inhibited CXCR3 ligand-driven chemotaxis of murine and human cells. Surface plasmon resonance studies revealed that EGCG bound directly to chemokines CXCL9, CXCL10, and CXCL11. These results indicated that one anti-inflammatory mechanism of EGCG is binding of proinflammatory chemokines and limiting their biological activities. These findings support further development of EGCG as a potent therapeutic for inflammatory diseases.
Assuntos
Catequina/análogos & derivados , Inibição de Migração Celular/imunologia , Quimiocinas/metabolismo , Mediadores da Inflamação/fisiologia , Pulmão/imunologia , Pulmão/patologia , Animais , Sítios de Ligação/imunologia , Catequina/metabolismo , Catequina/fisiologia , Células Cultivadas , Quimiocina CXCL10/antagonistas & inibidores , Quimiocina CXCL10/metabolismo , Quimiocina CXCL11/antagonistas & inibidores , Quimiocina CXCL11/metabolismo , Quimiocina CXCL9/antagonistas & inibidores , Quimiocina CXCL9/metabolismo , Quimiocinas/antagonistas & inibidores , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Camundongos TransgênicosRESUMO
Non-complaint Egyptian homes were examined to determine the residential culturable airborne bacterial concentrations so that these could be used as comparisons in indoor air quality investigations. Concentrations of airborne bacteria were investigated in 26 urban flats across Cairo and 17 rural flats in the Dakahlia governorate. Air samples were collected using a two-stage viable cascade impactor sampler, dividing particles into coarse (>8 µm) and fine (<8 µm) sizes. For urban flats, the year's median indoor and comparison site concentrations were 9133 CFU/m(3) and 9423 CFU/m(3), respectively. For rural flats, the year's median indoor and comparison site concentrations were 15,915 CFU/m(3) and 10,859 CFU/m(3), respectively. The median indoor bacterial concentrations increased in winter and spring compared to autumn and summer. Winter months had the greatest median concentration for coarse indoor organisms, whereas spring had the largest for the fine indoor organisms. Fine bacterial concentration composed more than 60% of the indoor bacterial fraction.
Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Bactérias/isolamento & purificação , Aerossóis/análise , Cidades , Egito , Monitoramento Ambiental , Umidade , Estações do Ano , TemperaturaRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has evolved into multiple variants. Animal models are important to understand variant pathogenesis, particularly for variants with mutations that have significant phenotypic or epidemiological effects. Here, cohorts of naive or previously infected Syrian hamsters (Mesocricetus auratus) were infected with variants to investigate viral pathogenesis and disease protection. Naive hamsters infected with SARS-CoV-2 variants had consistent clinical outcomes, tissue viral titers, and pathology, while hamsters that recovered from initial infection and were reinfected demonstrated less severe clinical disease and lung pathology than their naive counterparts. Males had more frequent clinical signs than females in most variant groups, but few sex variations in tissue viral titers and lung pathology were observed. These findings support the use of Syrian hamsters as a SARS-CoV-2 model and highlight the importance of considering sex differences when using this species. IMPORTANCE With the continued circulation and emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, understanding differences in the effects between the initial infection and a subsequent reinfection on disease pathogenesis is critical and highly relevant. This study characterizes Syrian hamsters as an animal model to study reinfection with SARS-CoV-2. Previous infection reduced the disease severity of reinfection with different SARS-CoV-2 variants.
Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Animais , Feminino , Humanos , Masculino , Mesocricetus , SARS-CoV-2/genética , COVID-19/patologia , Pulmão/patologia , Reinfecção/patologia , Modelos Animais de DoençasRESUMO
Peripheral neuropathy is the most common neurological complication of HIV-1 infection, affecting over one-third of infected individuals, including those treated with antiretroviral therapy. To study the pathogenesis of HIV-induced peripheral nervous system disease, we established a model in which SIV-infected macaques developed changes closely resembling alterations reported in components of the sensory pathway in HIV-infected individuals. Significant declines in epidermal nerve fiber density developed in SIV-infected macaques, similar to that of HIV-infected individuals with neuropathy. Changes in dorsal root ganglia (DRG) included macrophage infiltration, SIV replication in macrophages, immune activation of satellite cells, and neuronal loss. To determine whether dorsal root ganglion damage was associated with altered nerve function, we measured unmyelinated C-fiber conduction velocities (CV) in nerves of SIV-infected macaques and compared CV changes with DRG alterations. Twelve weeks postinoculation, SIV-infected macaques had significantly lower C-fiber conduction velocity in sural nerves than uninfected animals and the magnitude of conduction velocity decline correlated strongly with extent of DRG macrophage infiltration. Thus, injury to neurons in the DRG-mediated by activated macrophages-preceded altered conduction of unmyelinated nerve fibers in SIV-infected macaques, suggesting that macrophage-mediated DRG damage may be the initiating event in HIV-induced sensory neuropathy.
Assuntos
Gânglios Espinais/patologia , Macrófagos/patologia , Condução Nervosa/fisiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Animais , Macaca nemestrina , Macrófagos/virologia , Fibras Nervosas Amielínicas/fisiologia , Fibras Nervosas Amielínicas/virologia , Proteínas do Tecido Nervoso/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/virologia , Células Satélites Perineuronais/fisiologia , Síndrome de Imunodeficiência Adquirida dos Símios/patologia , Carga ViralRESUMO
Despite decreased rates of tobacco smoking in many areas, cigarette smoking remains a major contributor to many health problems. Cigarette smoking can reduce immune system functioning while concurrently increasing inflammation. Dendritic cells in the lung exposed to cigarette smoke become stimulated and go on to activate T-cells. Extracellular vesicles (EVs) are nano-sized particles released by cells. They participate in intercellular communication by transferring functional proteins and nucleic acids to recipient cells and have been implicated in immune responses. For example, they can display MHC-peptide complexes to activate T-cells. In the current study, we sought to understand the role of cigarette smoke extract (CSE) on dendritic cell-derived EVs and their capacity to activate and differentiate T-cells. Primary human dendritic cells (iDCs) were exposed to CSE and EVs were separated and characterized. We exposed autologous primary CD4 + T-cells to iDC-EVs and observed T helper cell populations skewing towards Th1 and Th17 phenotypes. As HIV + individuals are disproportionately likely to be current smokers, we also examined the effects of iDC-EVs on acutely infected T-cells as well as on a cell model of HIV latency (ACH-2). We found that in most cases, iDC-CSE EVs tended to reduce p24 release from the acutely infected primary T-cells, albeit with great variability. We did not observe large effects of iDC-EVs or direct CSE exposure on p24 release from the ACH-2 cell line. Together, these data suggest that iDC-CSE EVs have the capacity to modulate the immune responses, in part by pushing T-cells towards Th1 and Th17 phenotypes.
Assuntos
Fumar Cigarros , Vesículas Extracelulares , Células Dendríticas , Vesículas Extracelulares/metabolismo , Ativação Linfocitária , Replicação ViralRESUMO
This study examined the relationship between maternal food source and preparation during pregnancy and the duration of breastfeeding among 751 mother-child dyads in the United States. The data collected from the Environmental influences on Child Health Outcomes (ECHO) Program included twelve cohorts of mothers (age ≥ 18) who delivered infant(s). Three categories of maternal food source and preparation including, High, Moderate, or Low Food Source Quality were derived from the mother report. The mean duration of breastfeeding differed strongly across the three categories. The High Food Source Quality group breastfed an average of 41 weeks, while shorter durations were observed for the Moderate (26 weeks) and Low (16 weeks) Food Source Quality groups. Cox proportional hazards models were used to estimate the relative hazard of time to breastfeeding cessation for each participant characteristic. The full model adjusted for clustering/cohort effect for all participant characteristics, while the final model adjusted for the subset of characteristics identified from variable reduction modeling. The hazard of breastfeeding cessation for those in the High Food Source Quality group was 24% less than the Moderate group (RH = 0.76; 95% CI, 0.63-0.92). Pregnant women in the High Food Source Quality group breastfed longer than the Moderate and Low groups. We encourage more detailed studies in the future to examine this relationship longitudinally.
Assuntos
Aleitamento Materno , Mães , Lactente , Humanos , Feminino , Gravidez , Fatores de Tempo , Vitaminas , Avaliação de Resultados em Cuidados de SaúdeRESUMO
Infection by HIV-1 frequently leads to pulmonary complications, including alterations to local immune environments. To better understand these alterations, we have examined in detail the patterns and levels of expression of chemokine, cytokine, and chemokine receptor mRNAs in lung tissues from 16 uninfected or simian immunodeficiency virus (SIV)/DeltaB670 infected cynomolgus macaques at different stages of infection. Among the most up-regulated immune genes were interferon (IFN)-gamma, IFN-gamma-inducible CXCR3 ligands, and CCR5 ligands, as well as the cognate chemokine receptors. These changes were greatest in animals with clear Pneumocystis carinii coinfection. Immunohistochemistry and in situ hybridization revealed monocytes/macrophages to be the predominant type of cell infiltrating into lung tissues and serving as the major cellular source of chemokines. To explore the causes of chemokine alterations, we treated macaque lung cells with IFN-gamma, lipopolysaccharide, Poly(I:C), and P. carinii in vitro, and results revealed that these stimuli can induce the expression of CXCR3 ligand and/or CCR5 ligand mRNAs. Taken together, these studies provide a comprehensive definition of the chemokine networks available to modulate cellular recruitment to lung tissues during SIV infection and implicate both cytokines (IFN-gamma) and pathogens (SIV and P. carinii) as contributors to increased expression of pro-inflammatory chemokines.
Assuntos
Quimiocinas/imunologia , Pulmão/imunologia , Pneumocystis carinii/imunologia , Pneumonia por Pneumocystis/imunologia , Receptores de Quimiocinas/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Quimiocinas/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Pulmão/metabolismo , Pulmão/virologia , Macaca fascicularis , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/metabolismo , Pneumonia por Pneumocystis/virologia , Receptores de Quimiocinas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome de Imunodeficiência Adquirida dos Símios/complicações , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Estatísticas não ParamétricasRESUMO
The molecular mechanisms underlying learning and memory impairment in patients with HIV-associated neurological disease have remained unclear. Calcium/calmodulin-dependent kinase II (CaMKII) has key roles in synaptic potentiation and memory storage in neurons and also may have immunomodulatory functions. To determine whether HIV and simian immunodeficiency virus (SIV) induce alterations in CaMKII expression and/or activation (autophosphorylation) in the brain, we measured CaMKII alterations by quantitative immunoblotting in both an in vitro HIV/neuronal culture model and in vivo in an SIV-infected macaque model of HIV-associated neurological damage. Using primary rat hippocampal neuronal cultures treated with culture supernatants harvested from HIV-1-infected human monocyte-derived macrophages (HIV/MDM), we found that CaMKII activation declined after exposure of neurons to HIV/MDM. Consistent with our in vitro measurements, a significant decrease in CaMKII activation was present in both the hippocampus and frontal cortex of SIV-infected macaques compared with uninfected animals. In SIV-infected animals, total CaMKII expression in the hippocampus correlated well with levels of synaptophysin. Furthermore, CaMKII expression in both the hippocampus and frontal cortex was inversely correlated with viral load in the brain. These findings suggest that alterations in CaMKII may compromise synaptic function in the early phases of chronic neurodegenerative processes induced by HIV.