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1.
J Clin Microbiol ; 62(2): e0083623, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38206000

RESUMO

HIV is an ongoing global epidemic with estimates of more than a million new infections occurring annually. To combat viral spread, continuous innovations in areas including testing and treatment are necessary. In the United States, the Centers for Disease Control and Prevention recommend that laboratories follow an HIV testing algorithm that first uses a US Food and Drug Administration approved immunoassay to detect antibodies to HIV-1 or HIV-2 as well as HIV-1 p24 antigen in serum or plasma samples. An initially reactive specimen is tested by a supplemental assay for confirmation and to differentiate antibodies to HIV-1 or HIV-2. There are few Food and Drug Administration (FDA)-approved supplemental differentiation tests currently available. A multicenter investigation was conducted to determine the clinical performance for two independent versions of the Avioq VioOne HIV Profile Supplemental Assay (Avioq, Inc., Research Triangle Park, NC). The performance of both assay versions compared favorably with the performance parameters for the Geenius HIV 1/2 Supplemental Assay as published in that assay package insert (Bio-Rad Laboratories, Hercules, CA), the current gold standard for HIV supplemental testing. When comparing the two VioOne assays, version 2 (lacking HIV-2 p27 antibody detection) demonstrated improved reproducibility, specificity, and sensitivity as compared to its predecessor. IMPORTANCE We evaluated the reproducibility, sensitivity, and specificity data for two versions of the VioOne HIV Profile Supplemental Assay and compared these results back to similar results for the Geenius HIV 1/2 Supplemental Assay that are publicly available. Our study concluded that the VioOne HIV Profile Supplemental Assay compared favorably with the Geenius HIV 1/2 Supplemental Assay, thus providing an additional option for clinical laboratories to improve and expand their HIV testing capabilities.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Estados Unidos , Reprodutibilidade dos Testes , Anticorpos Anti-HIV , Algoritmos , HIV-2 , Proteína do Núcleo p24 do HIV , Sensibilidade e Especificidade
2.
PLoS One ; 18(10): e0288743, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883384

RESUMO

BACKGROUND: HLA antibody testing is essential for successful solid-organ allocation, patient monitoring post-transplant, and risk assessment for both solid-organ and hematopoietic transplant patients. Luminex solid-phase testing is the most common method for identifying HLA antibody specificities, making it one of the most complex immunoassays as each panel contains over 90 specificities for both HLA class I and HLA class II with most of the analysis being performed manually in the vendor-provided software. Principal component analysis (PCA), used in machine learning, is a feature extraction method often utilized to assess data with many variables. METHODS & FINDINGS: In our study, solid organ transplant patients who exhibited HLA donor-specific antibodies (DSAs) were used to characterize the utility of PCA-derived analysis when compared to a control group of post-transplant and pre-transplant patients. ROC analysis was utilized to determine a potential threshold for the PCA-derived analysis that would indicate a significant change in a patient's single antigen bead pattern. To evaluate if the algorithm could identify differences in patterns on HLA class I and HLA class II single antigen bead results using the optimized threshold, HLA antibody test results were analyzed using PCA-derived analysis and compared to the clinical results for each patient sample. The PCA-derived algorithm had a sensitivity of 100% (95% CI, 73.54%-100%), a specificity of 75% (95% CI, 56.30%-92.54%), with a PPV of 65% (95% CI, 52.50%-83.90%) and an NPV of 100%, in identifying new reactivity that differed from the patients historic HLA antibody pattern. Additionally, PCA-derived analysis was utilized to assess the potential over-reactivity of single antigen beads for both HLA class I and HLA class II antibody panels. This assessment of antibody results identified several beads in both the HLA class I and HLA class II antibody panel which exhibit over reactivity from 2018 to the present time. CONCLUSIONS: PCA-derived analysis would be ideal to help automatically identify patient samples that have an HLA antibody pattern of reactivity consistent with their history and those which exhibit changes in their antibody patterns which could include donor-specific antibodies, de novo HLA antibodies, and assay interference. A similar method could also be applied to evaluate the over-reactivity of beads in the HLA solid phase assays which would be beneficial for lot comparisons and instructive for transplant centers to better understand which beads are more prone to exhibiting over-reactivity and impact patient care.


Assuntos
Transplante de Rim , Transplante de Órgãos , Humanos , Transplante de Rim/métodos , Análise de Componente Principal , Isoanticorpos , Rejeição de Enxerto , Antígenos HLA , Teste de Histocompatibilidade/métodos
5.
mBio ; 13(5): e0175122, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36135380

RESUMO

COVID-19 convalescent plasma (CCP) was an early and widely adopted putative therapy for severe COVID-19. Results from randomized control trials and observational studies have failed to demonstrate a clear therapeutic role for CCP for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Underlying these inconclusive findings is a broad heterogeneity in the concentrations of neutralizing antibodies (nAbs) between different CCP donors. We conducted this study to evaluate the effectiveness and safety of nAb titer-defined CCP in adults admitted to an academic referral hospital. Patients positive by a SARS-CoV-2 nucleic acid amplification test and with symptoms for <10 days were eligible. Participants received either CCP with nAb titers of >1:640 (high-titer group) or ≥1:160 to 1:640 (standard-titer group) in addition to standard of care treatments. The primary clinical outcome was time to hospital discharge, with mortality and respiratory support evaluated as secondary outcomes. Adverse events were contrasted by CCP titer. Between 28 August and 4 December 2020, 316 participants were screened, and 55 received CCP, with 14 and 41 receiving high- versus standard-titer CCP, respectively. Time to hospital discharge was shorter among participants receiving high- versus standard-titer CCP, accounting for death as a competing event (hazard ratio, 1.94; 95% confidence interval [CI], 1.05 to 3.58; Gray's P = 0.02). Severe adverse events (SAEs) (≥grade 3) occurred in 4 (29%) and 23 (56%) of participants receiving the high versus standard titer, respectively, by day 28 (risk ratio, 0.51; 95% CI, 0.21 to 1.22; Fisher's P = 0.12). There were no observed treatment-related AEs. (This study has been registered at ClinicalTrials.gov under registration no. NCT04524507). IMPORTANCE In this study, in a high-risk population of patients admitted for COVID-19, we found an earlier time to hospital discharge among participants receiving CCP with nAb titers of >1:640 compared with participants receiving CCP with a lower nAb titer and no CCP-related AEs. The significance of our research is in identifying a dose response of CCP and clinical outcomes based on nAb titer. Although limited by a small study size, these findings support further study of high-nAb-titer CCP defined as >1:640 in the treatment of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/terapia , Imunização Passiva/métodos
6.
J Immunol Methods ; 509: 113340, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36030829

RESUMO

BACKGROUND: Detection of latent Mycobacterium tuberculosis (LTBI) in patients is important to prevent active infection and the spread of disease, particularly in vulnerable patient populations. In 2020, a kit on the high throughput Liaison XL (DiaSorin) became commercially available for the analysis of QuantiFERON-TB Gold Plus assay (Qiagen). Pilot testing indicated suboptimal repeatability of some samples with this assay. This study provides an extensive assessment of repeatability with DiaSorin system. RESULTS: Repeat testing of 481 IGRA positive samples, demonstrated substantial variability upon repeat analysis. Repeat results for TB1 and TB2 tubes, showed 73.73% and 72.82% concordance with initial results, respectively. TB1 and TB2 tube values minus the nil (IU/mL) were significantly higher in samples that were repeat positive (p < 0.001). Repeat results had better concordance with initial results if both TB1 and TB2 tubes were positive. Samples with TB1 tube values minus the nil (IU/mL) ≥ 4.54 and TB2 tube values minus the nil (IU/mL) ≥ 4.78 were found to always repeat positive. Assigning a threshold of 1.55 IU/mL for the TB1 tube value minus the nil and 1.45 IU/mL for the TB2 tube value minus the nil yielded a positive predictive value ≥95%. CONCLUSION: These results identified a potential role for retesting of select IGRA positive samples on the Diasorin Liaison XL platform due to the high proportion of samples that show a lack of repeatability. Additionally, we identified a threshold that would determine samples most likely to repeat test positive and which samples should be retested.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Humanos , Testes de Liberação de Interferon-gama/métodos , Tuberculose Latente/diagnóstico , Tuberculose Latente/microbiologia , Luminescência , Valor Preditivo dos Testes
7.
Front Genet ; 13: 901377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35879986

RESUMO

HLA typing provides essential results for stem cell and solid organ transplants, as well as providing diagnostic benefits for various rheumatology, gastroenterology, neurology, and infectious diseases. It is becoming increasingly clear that understanding the expression of patient HLA transcripts can provide additional benefits for many of these same patient groups. Our study cohort was evaluated using a long-read RNA sequencing methodology to provide rapid HLA genotyping results and normalized HLA transcript expression. Our assay used NGSEngine to determine the HLA genotyping result and normalized mRNA transcript expression using Athlon2. The assay demonstrated an excellent concordance rate of 99.7%. Similar to previous studies, for the class I loci, patients demonstrated significantly lower expression of HLA-C than HLA-A and -B (Mann-Whitney U, p value = 0.0065 and p value = 0.0154, respectively). In general, the expression of class II transcripts was lower than that of class I transcripts. This study demonstrates a rapid high-resolution HLA typing assay using RNA-Seq that can provide accurate HLA genotyping and HLA allele-specific transcript expression in 7-8 h, a timeline short enough to perform the assay for deceased donors.

8.
Eur J Investig Health Psychol Educ ; 11(4): 1503-1515, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34940385

RESUMO

Juvenile systemic lupus erythematosus (JSLE) is diagnosed in children younger than 18 years of age. Depression and anxiety are common, but not well understood in JSLE. We investigated the clinical and psychological factors associated with the psychological manifestations of JSLE. Twenty-nine JSLE patients were recruited for the study. Patients completed surveys evaluating their psychological status and perceptions about their health. Medical records were used to obtain laboratory results. The JSLE patient population was compared with adult-onset SLE (ASLE) patients and unaffected controls. Kidney involvement was associated with depression in the JSLE patients. The BUN levels, BUN/creatinine ratio, and leukocyturia were all significantly associated with depressive symptoms. Multivariate analysis found that the BUN/creatinine ratio was the most predictive value for both depression and anxiety. Depressive symptoms in JSLE were less pronounced than in ASLE, although anxiety was not different. Age and education are likely to be protective against depression in the JSLE patients. These findings may indicate that symptomatology is an important indicator of whether the patient needs psychiatric care.

10.
Hum Immunol ; 82(11): 829-837, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34521569

RESUMO

Histocompatibility testing is essential for donor identification and risk assessment in solid organ and hematopoietic stem cell transplant. Additionally, it is useful for identifying donor specific alleles for monitoring donor specific antibodies in post-transplant patients. Next-generation sequence (NGS) based human leukocyte antigen (HLA) typing has improved many aspects of histocompatibility testing in hematopoietic stem cell and solid organ transplant. HLA disease association testing and research has also benefited from the advent of NGS technologies. In this review we discuss the current impact and future applications of NGS typing on clinical histocompatibility testing for transplant and non-transplant purposes.


Assuntos
Seleção do Doador/métodos , Antígenos HLA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Teste de Histocompatibilidade/métodos , Alelos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Laboratórios Clínicos , Transplante de Órgãos/efeitos adversos , Análise de Sequência de DNA
11.
mSphere ; 6(4): e0027521, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431693

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) has now caused over 2 million deaths worldwide and continues to expand. Currently, much is unknown about functionally neutralizing human antibody responses and durability to SARS-CoV-2 months after infection or the reason for the discrepancy in COVID-19 disease and sex. Using convalescent-phase sera collected from 101 COVID-19-recovered individuals 21 to 212 days after symptom onset with 48 additional longitudinal samples, we measured functionality and durability of serum antibodies. We also evaluated associations of individual demographic and clinical parameters with functional neutralizing antibody responses to COVID-19. We found robust antibody durability out to 6 months, as well as significant positive associations with the magnitude of the neutralizing antibody response and male sex and in individuals with cardiometabolic comorbidities. IMPORTANCE In this study, we found that neutralizing antibody responses in COVID-19-convalescent individuals vary in magnitude but are durable and correlate well with receptor binding domain (RBD) Ig binding antibody levels compared to other SARS-CoV-2 antigen responses. In our cohort, higher neutralizing antibody titers are independently and significantly associated with male sex compared to female sex. We also show for the first time that higher convalescent antibody titers in male donors are associated with increased age and symptom grade. Furthermore, cardiometabolic comorbidities are associated with higher antibody titers independently of sex. Here, we present an in-depth evaluation of serologic, demographic, and clinical correlates of functional antibody responses and durability to SARS-CoV-2 which supports the growing literature on sex discrepancies regarding COVID-19 disease morbidity and mortality, as well as functional neutralizing antibody responses to SARS-CoV-2.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Formação de Anticorpos/imunologia , COVID-19/virologia , Estudos de Coortes , Feminino , Humanos , Imunização Passiva/métodos , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
12.
J Clin Microbiol ; 59(10): e0081121, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34232708

RESUMO

SARS-CoV-2 is a novel positive-sense single-stranded RNA virus that has caused a recent pandemic. Most patients have a mild disease course, while approximately 20% have moderate to severe disease, often requiring hospitalization and, in some cases, care in the intensive care unit. By investigating a perceived increased rate of indeterminate QuantiFERON-TB Gold Plus results in hospitalized COVID patients, we demonstrate that severely ill COVID-19 patients have at least a 6-fold reduction of interferon gamma (IFN-γ) levels compared to control patients. What is more, over 60% of these severely ill COVID-19 patients' peripheral T cells were found to be unable to produce measurable IFN-γ when stimulated with phytohemagglutinin (PHA), a potent IFN-γ mitogen, reflected by an indeterminate QuantiFERON-TB Gold Plus result. This defect of IFN-γ production was independent of absolute lymphocyte counts and immunosuppressive therapy. It was associated with increased levels of interleukin-6 (IL-6), which was a predictor of patient outcomes for our cohort when measured early in the course of disease. Finally, in a subset of COVID-19 patients, we found elevated IL-10 levels in addition to IL-6 elevation. In addition to finding a significant limitation of interferon-gamma release assay (IGRA) testing in severely ill COVID-19 patients, these data provide evidence that many of these patients demonstrate a focused Th2 immune response with inhibition of IFN-γ signaling and, in many cases, significant elevations of IL-6.


Assuntos
COVID-19 , Tuberculose Latente , Humanos , Interferon gama , Testes de Liberação de Interferon-gama , SARS-CoV-2
13.
Sci Rep ; 11(1): 6354, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737712

RESUMO

Autoimmune diseases are driven largely by a pathogenic cytokine milieu produced by aberrantly activated lymphocytes. Many cytokines, including interferon gamma (IFN-γ), utilize the JAK/STAT pathway for signal propagation. Suppressor of Cytokine Signaling-1 (SOCS1) is an inducible, intracellular protein that regulates IFN-γ signaling by dampening JAK/STAT signaling. Using Fas deficient, MRL/MpJ-Faslpr/J (MRL/lpr) mice, which develop lupus-like disease spontaneously, we tested the hypothesis that a peptide mimic of the SOCS1 kinase inhibitory region (SOCS1-KIR) would inhibit lymphocyte activation and modulate lupus-associated pathologies. Consistent with in vitro studies, SOCS1-KIR intraperitoneal administration reduced the frequency, activation, and cytokine production of memory CD8+ and CD4+ T lymphocytes within the peripheral blood, spleen, and lymph nodes. In addition, SOCS1-KIR administration reduced lymphadenopathy, severity of skin lesions, autoantibody production, and modestly reduced kidney pathology. On a cellular level, peritoneal SOCS1-KIR administration enhanced Foxp3 expression in total splenic and follicular regulatory T cells, reduced the effector memory/naïve T lymphocyte ratio for both CD4+ and CD8+ cells, and reduced the frequency of GL7+ germinal center enriched B cells. Together, these data show that SOCS1-KIR treatment reduced auto-reactive lymphocyte effector functions and suggest that therapeutic targeting of the SOCS1 pathway through peptide administration may have efficacy in mitigating autoimmune pathologies.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Fatores de Transcrição Forkhead/genética , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Peptídeos/farmacologia , Proteína 1 Supressora da Sinalização de Citocina/genética , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B/efeitos dos fármacos , Biomimética , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Citocinas/genética , Interferon gama/genética , Janus Quinases/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Camundongos Endogâmicos MRL lpr , Peptídeos/síntese química , Fatores de Transcrição STAT/genética , Baço/efeitos dos fármacos , Baço/imunologia , Proteína 1 Supressora da Sinalização de Citocina/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Receptor fas/genética
14.
medRxiv ; 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33564775

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has now caused over 2 million deaths worldwide and continues to expand. Currently, much is unknown about functionally neutralizing human antibody responses and durability to SARS-CoV-2. Using convalescent sera collected from 101 COVID-19 recovered individuals 21-212 days after symptom onset with forty-eight additional longitudinal samples, we measured functionality and durability of serum antibodies. We also evaluated associations between individual demographic and clinical parameters with functional neutralizing antibody responses to COVID-19. We found robust antibody durability out to six months, as well as significant positive associations with the magnitude of the neutralizing antibody response and male sex. We also show that SARS-CoV-2 convalescent neutralizing antibodies are higher in individuals with cardio-metabolic comorbidities.

15.
mBio ; 11(5)2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994333

RESUMO

Characterizing the asymptomatic spread of SARS-CoV-2 is important for understanding the COVID-19 pandemic. This study was aimed at determining asymptomatic spread of SARS-CoV-2 in a suburban, Southern U.S. population during a period of state restrictions and physical distancing mandates. This is one of the first published seroprevalence studies from North Carolina and included multicenter, primary care, and emergency care facilities serving a low-density, suburban and rural population since description of the North Carolina state index case introducing the SARS-CoV-2 respiratory pathogen to this population. To estimate point seroprevalence of SARS-CoV-2 among asymptomatic individuals over time, two cohort studies were examined. The first cohort study, named ScreenNC, was comprised of outpatient clinics, and the second cohort study, named ScreenNC2, was comprised of inpatients unrelated to COVID-19. Asymptomatic infection by SARS-CoV-2 (with no clinical symptoms) was examined using an Emergency Use Authorization (EUA)-approved antibody test (Abbott) for the presence of SARS-CoV-2 IgG. This assay as performed under CLIA had a reported specificity/sensitivity of 100%/99.6%. ScreenNC identified 24 out of 2,973 (0.8%) positive individuals among asymptomatic participants accessing health care during 28 April to 19 June 2020, which was increasing over time. A separate cohort, ScreenNC2, sampled from 3 March to 4 June 2020, identified 10 out of 1,449 (0.7%) positive participants.IMPORTANCE This study suggests limited but accelerating asymptomatic spread of SARS-CoV-2. Asymptomatic infections, like symptomatic infections, disproportionately affected vulnerable communities in this population, and seroprevalence was higher in African American participants than in White participants. The low, overall prevalence may reflect the success of shelter-in-place mandates at the time this study was performed and of maintaining effective physical distancing practices among suburban populations. Under these public health measures and aggressive case finding, outbreak clusters did not spread into the general population.


Assuntos
Doenças Assintomáticas/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Programas Obrigatórios , North Carolina/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos
16.
Sci Immunol ; 5(48)2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527802

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that first emerged in late 2019 is responsible for a pandemic of severe respiratory illness. People infected with this highly contagious virus can present with clinically inapparent, mild, or severe disease. Currently, the virus infection in individuals and at the population level is being monitored by PCR testing of symptomatic patients for the presence of viral RNA. There is an urgent need for SARS-CoV-2 serologic tests to identify all infected individuals, irrespective of clinical symptoms, to conduct surveillance and implement strategies to contain spread. As the receptor binding domain (RBD) of the spike protein is poorly conserved between SARS-CoVs and other pathogenic human coronaviruses, the RBD represents a promising antigen for detecting CoV-specific antibodies in people. Here we use a large panel of human sera (63 SARS-CoV-2 patients and 71 control subjects) and hyperimmune sera from animals exposed to zoonotic CoVs to evaluate RBD's performance as an antigen for reliable detection of SARS-CoV-2-specific antibodies. By day 9 after the onset of symptoms, the recombinant SARS-CoV-2 RBD antigen was highly sensitive (98%) and specific (100%) for antibodies induced by SARS-CoVs. We observed a strong correlation between levels of RBD binding antibodies and SARS-CoV-2 neutralizing antibodies in patients. Our results, which reveal the early kinetics of SARS-CoV-2 antibody responses, support using the RBD antigen in serological diagnostic assays and RBD-specific antibody levels as a correlate of SARS-CoV-2 neutralizing antibodies in people.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Epitopos Imunodominantes/imunologia , Pneumonia Viral/diagnóstico , Domínios Proteicos/imunologia , Glicoproteína da Espícula de Coronavírus/química , Zoonoses/sangue , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , COVID-19 , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Humanos , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/virologia , Ligação Proteica , Coelhos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/química , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , SARS-CoV-2 , Testes Sorológicos , Zoonoses/virologia
17.
medRxiv ; 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32511572

RESUMO

A new Severe Acute Respiratory Syndrome Coronavirus variant (SARS-CoV-2) that first emerged in late 2019 is responsible for a pandemic of severe respiratory illness. People infected with this highly contagious virus present with clinically inapparent, mild or severe disease. Currently, the presence of the virus in individual patients and at the population level is being monitored by testing symptomatic cases by PCR for the presence of viral RNA. There is an urgent need for SARS-CoV-2 serologic tests to identify all infected individuals, irrespective of clinical symptoms, to conduct surveillance and implement strategies to contain spread. As the receptor binding domain (RBD) of the viral spike (S) protein is poorly conserved between SARS-CoVs and other pathogenic human coronaviruses, the RBD represents a promising antigen for detecting CoV specific antibodies in people. Here we use a large panel of human sera (70 SARS-CoV-2 patients and 71 control subjects) and hyperimmune sera from animals exposed to zoonotic CoVs to evaluate the performance of the RBD as an antigen for accurate detection of SARS-CoV-2-specific antibodies. By day 9 after the onset of symptoms, the recombinant SARS-CoV-2 RBD antigen was highly sensitive (98%) and specific (100%) to antibodies induced by SARS-CoVs. We observed a robust correlation between levels of RBD binding antibodies and SARS-CoV-2 neutralizing antibodies in patients. Our results, which reveal the early kinetics of SARS-CoV-2 antibody responses, strongly support the use of RBD-based antibody assays for population-level surveillance and as a correlate of neutralizing antibody levels in people who have recovered from SARS-CoV-2 infections.

18.
JCI Insight ; 5(11)2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32493841

RESUMO

Patients with systemic lupus erythematosus (SLE) present a high incidence of atherosclerosis, which contributes significantly to morbidity and mortality in this autoimmune disease. An impaired balance between regulatory (Treg) and follicular helper (Tfh) CD4+ T cells is shared by both diseases. However, whether there are common mechanisms of CD4+ T cell dysregulation between SLE and atherosclerosis remains unclear. Pre-B cell leukemia transcription factor 1 isoform d (Pbx1d) is a lupus susceptibility gene that regulates Tfh cell expansion and Treg cell homeostasis. Here, we investigated the role of T cells overexpressing Pbx1d in low-density lipoprotein receptor-deficient (Ldlr-/-) mice fed with a high-fat diet, an experimental model for atherosclerosis. Pbx1d-transgenic T cells exacerbated some phenotypes of atherosclerosis, which were associated with higher autoantibody production, increased Tfh cell frequency, and impaired Treg cell regulation, in Ldlr-/- mice as compared with control T cells. In addition, we showed that dyslipidemia and Pbx1d-transgenic expression independently impaired the differentiation and function of Treg cells in vitro, suggesting a gene/environment additive effect. Thus, our results suggest that the combination of Pbx1d expression in T cells and dyslipidemia exacerbates both atherosclerosis and autoimmunity, at least in part through a dysregulation of Treg cell homeostasis.


Assuntos
Alelos , Aterosclerose , Dislipidemias , Regulação da Expressão Gênica/imunologia , Fator de Transcrição 1 de Leucemia de Células Pré-B/imunologia , Linfócitos T Reguladores , Animais , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/patologia , Dislipidemias/genética , Dislipidemias/imunologia , Dislipidemias/patologia , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Camundongos Knockout , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
19.
Immunohorizons ; 4(6): 319-331, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540987

RESUMO

CTLA4Ig, a reagent that inhibits CD28 signaling, has shown therapeutic efficacy in mouse models of lupus nephritis (LN) when combined with several other biologics or standard of care drugs. Unfortunately, clinical trials treating LN patients with CTLA4Ig (abatacept) have not met endpoints. Metformin, a drug used to control hyperglycemia that inhibits mitochondrial metabolism, lowered the effective dose of glucocorticoids and prevented major flares when added on to the standard of care treatment of lupus patients with low disease activity. Metformin combined with inhibition of glycolysis by 2-deoxyglucose showed therapeutic efficacy in multiple mouse models of LN. Because CD28 signaling triggers glucose metabolism in T cells, we hypothesized that combining CTLA4Ig treatment with metformin would have the same effect. In this study, we showed that the combination of metformin and CTLA4Ig decreased the development of LN in (NZB × NZW)F1 mice treated at the early stage of disease. This preventive effect was associated with a decreased expansion of CD4+ T cell effector subsets. However, contrary to the combination with 2-deoxyglucose, metformin combined with CTLA4Ig did not alter autoantibody production, suggesting different mechanisms of symptom mitigation. Overall, this study shows therapeutic efficacy of the combination of metformin and CTLA4Ig, two drugs with established safety records, in a preclinical mouse model of LN.


Assuntos
Abatacepte/farmacologia , Imunossupressores/farmacologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/prevenção & controle , Metformina/farmacologia , Animais , Antígenos CD , Autoanticorpos/sangue , Linfócitos T CD4-Positivos/imunologia , Antígeno CTLA-4 , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Nefrite Lúpica/tratamento farmacológico , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos NZB , Subpopulações de Linfócitos T/imunologia
20.
Curr Opin Immunol ; 61: 10-16, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31422315

RESUMO

Metabolism has recently emerged as an essential mechanism that regulates the immune system. Studies in healthy mice and, to a lesser extent, humans, have defined the metabolism of immune cells in response to various challenges. It is increasingly recognized that the overactive immune system that drives autoimmune diseases presents metabolic abnormalities that offer therapeutic opportunities. These novel therapeutic venues are supported by a few studies using metabolic inhibitors in mouse models and in small clinical trials. Reaching the full potential of targeting immuno-metabolism in autoimmune diseases requires a systemic cell-specific characterization of metabolic pathways in mouse models and cells from patients. Here, we review recent reports of immuno-metabolic alterations in autoimmune diseases, as well as alterations in immune effector pathways that have been implicated in autoimmunity, with a focus on systemic lupus erythematosus.


Assuntos
Doenças Autoimunes/etiologia , Doenças Autoimunes/metabolismo , Autoimunidade , Metabolismo Energético , Animais , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/terapia , Biomarcadores , Regulação da Expressão Gênica , Humanos , Sistema Imunitário , Imunomodulação , Redes e Vias Metabólicas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular , Transdução de Sinais , Estresse Fisiológico
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