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2.
PLoS One ; 16(8): e0255972, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34370787

RESUMO

Torque Teno Virus (TTV) is a small, non-enveloped, single-stranded and circular DNA virus that infects the majority of the population worldwide. Increased levels of plasma TTV viral load have been observed in various situations of immune deficiency or dysregulation, and several studies have suggested that TTV levels may be inversely correlated with immune competence. The measurement of TTV viremia by qPCR has been proposed as a potential biomarker for the follow-up of functional immune competence in immunosuppressed individuals, particularly hematopoietic stem cell transplant recipients. We hypothesized that TTV viral load could be used as a prognostic marker of immune checkpoint inhibitor (ICI) efficacy, and therefore investigated the TTV viral load in melanoma patients treated with nivolumab or pembrolizumab before and after 6 months of treatment. In the present study, TTV viral load was not different in melanoma patients before anti-PD-1 introduction compared to healthy volunteers, was not modified by ICI treatment and did not allowed to distinguish patients with treatment-sensitive tumor from patients with treatment-resistant tumor.

3.
J Exp Med ; 218(10)2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34357402

RESUMO

IFN-I and IFN-III immunity in the nasal mucosa is poorly characterized during SARS-CoV-2 infection. We analyze the nasal IFN-I/III signature, namely the expression of ISGF-3-dependent IFN-stimulated genes, in mildly symptomatic COVID-19 patients and show its correlation with serum IFN-α2 levels, which peak at symptom onset and return to baseline from day 10 onward. Moreover, the nasal IFN-I/III signature correlates with the nasopharyngeal viral load and is associated with the presence of infectious viruses. By contrast, we observe low nasal IFN-I/III scores despite high nasal viral loads in a subset of critically ill COVID-19 patients, which correlates with the presence of autoantibodies (auto-Abs) against IFN-I in both blood and nasopharyngeal mucosa. In addition, functional assays in a reconstituted human airway epithelium model of SARS-CoV-2 infection confirm the role of such auto-Abs in abrogating the antiviral effects of IFN-I, but not those of IFN-III. Thus, IFN-I auto-Abs may compromise not only systemic but also local antiviral IFN-I immunity at the early stages of SARS-CoV-2 infection.


Assuntos
Autoanticorpos/imunologia , COVID-19/imunologia , Interferon Tipo I/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Animais , Antivirais/imunologia , Antivirais/farmacologia , Autoanticorpos/sangue , COVID-19/sangue , COVID-19/virologia , Chlorocebus aethiops , Feminino , Humanos , Interferon Tipo I/farmacologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/imunologia , Cavidade Nasal/virologia , Estudos Prospectivos , SARS-CoV-2/fisiologia , Células Vero , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/imunologia
4.
Sci Immunol ; 6(62)2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413139

RESUMO

Circulating autoantibodies (auto-Abs) neutralizing high concentrations (10 ng/mL, in plasma diluted 1 to 10) of IFN-α and/or -ω are found in about 10% of patients with critical COVID-19 pneumonia, but not in subjects with asymptomatic infections. We detect auto-Abs neutralizing 100-fold lower, more physiological, concentrations of IFN-α and/or -ω (100 pg/mL, in 1/10 dilutions of plasma) in 13.6% of 3,595 patients with critical COVID-19, including 21% of 374 patients > 80 years, and 6.5% of 522 patients with severe COVID-19. These antibodies are also detected in 18% of the 1,124 deceased patients (aged 20 days-99 years; mean: 70 years). Moreover, another 1.3% of patients with critical COVID-19 and 0.9% of the deceased patients have auto-Abs neutralizing high concentrations of IFN-ß. We also show, in a sample of 34,159 uninfected subjects from the general population, that auto-Abs neutralizing high concentrations of IFN-α and/or -ω are present in 0.18% of individuals between 18 and 69 years, 1.1% between 70 and 79 years, and 3.4% >80 years. Moreover, the proportion of subjects carrying auto-Abs neutralizing lower concentrations is greater in a subsample of 10,778 uninfected individuals: 1% of individuals <70 years, 2.3% between 70 and 80 years, and 6.3% >80 years. By contrast, auto-Abs neutralizing IFN-ß do not become more frequent with age. Auto-Abs neutralizing type I IFNs predate SARS-CoV-2 infection and sharply increase in prevalence after the age of 70 years. They account for about 20% of both critical COVID-19 cases in the over-80s, and total fatal COVID-19 cases.


Assuntos
Autoanticorpos/imunologia , COVID-19/imunologia , Interferon Tipo I/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Autoanticorpos/sangue , COVID-19/mortalidade , Estudos de Casos e Controles , Criança , Pré-Escolar , Estado Terminal , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Recém-Nascido , Interferon-alfa/imunologia , Pessoa de Meia-Idade , Adulto Jovem
5.
Sci Rep ; 11(1): 14977, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294751

RESUMO

A comprehensive clinical and microbiological assessments of COVID-19 in front-line healthcare workers (HCWs) is needed. Between April 10th and May 28th, 2020, 319 HCWs with acute illness were reviewed. In addition to SARS-CoV-2 RT-PCR screening, a multiplex molecular panel was used for testing other respiratory pathogens. For SARS-CoV-2 positive HCWs, the normalized viral load, viral culture, and virus neutralization assays were performed weekly. For SARS-CoV-2 negative HCWs, SARS-CoV-2 serological testing was performed one month after inclusion. Among the 319 HCWs included, 67 (21.0%) were tested positive for SARS-CoV-2; 65/67 (97.0%) developed mild form of COVID-19. Other respiratory pathogens were found in 6/66 (9.1%) SARS-CoV-2 positive and 47/241 (19.5%) SARS-Cov-2 negative HCWs (p = 0.07). The proportion of HCWs with a viral load > 5.0 log10 cp/mL (Ct value < 25) was less than 15% at 8 days after symptom onset; 12% of HCWs were positive after 40 days (Ct > 37). More than 90% of cultivable virus had a viral load > 4.5 log10 cp/mL (Ct < 26) and were collected within 10 days after symptom onset. Among negative HCWs, 6/190 (3.2%) seroconverted. Our data suggest that the determination of viral load can be used for appreciating the infectiousness of infected HCWs. These data could be helpful for facilitating their return to work.


Assuntos
COVID-19/diagnóstico , Pessoal de Saúde , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , Teste de Ácido Nucleico para COVID-19 , Teste Sorológico para COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Carga Viral , Adulto Jovem
6.
Infect Dis Ther ; 10(3): 1747-1763, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34245450

RESUMO

INTRODUCTION: COVID-19 long-haulers, also decribed as having "long-COVID" or post-acute COVID-19 syndrome, represent 10% of COVID-19 patients and remain understudied. METHODS: In this prospective study, we recruited 30 consecutive patients seeking medical help for persistent symptoms (> 30 days) attributed to COVID-19. All reported a viral illness compatible with COVID-19. The patients underwent a multi-modal evaluation, including clinical, psychologic, virologic and specific immunologic assays and were followed longitudinally. A group of 17 convalescent COVID-19 individuals without persistent symptoms were included as a comparison group. RESULTS: The median age was 40 [interquartile range: 35-54] years and 18 (60%) were female. At a median time of 152 [102-164] days after symptom onset, fever, cough and dyspnea were less frequently reported compared with the initial presentation, but paresthesia and burning pain emerged in 18 (60%) and 13 (43%) patients, respectively. The clinical examination was unremarkable in all patients, although the median fatigue and pain visual analog scales were 7 [5-8] and 5 [2-6], respectively. Extensive biologic studies were unremarkable, and multiplex cytokines and ultra-sensitive interferon-α2 measurements were similar between long-haulers and convalescent COVID-19 individuals without persistent symptoms. Using SARS-CoV-2 serology and IFN-γ ELISPOT, we found evidence of a previous SARS-CoV-2 infection in 50% (15/30) of patients, with evidence of a lack of immune response, or a waning immune response, in two patients. Finally, psychiatric evaluation showed that 11 (36.7%), 13 (43.3%) and 9 (30%) patients had a positive screening for anxiety, depression and post-traumatic stress disorder, respectively. CONCLUSIONS: Half of patients seeking medical help for post-acute COVID-19 syndrome lack SARS-CoV-2 immunity. The presence of SARS-CoV-2 immunity, or not, had no consequence on the clinical or biologic characteristics of post-acute COVID-19 syndrome patients, all of whom reported severe fatigue, altered quality of life and psychologic distress.

7.
Emerg Microbes Infect ; 10(1): 1499-1502, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34176436

RESUMO

SARS-CoV-2 mutations appeared recently and can lead to conformational changes in the spike protein and probably induce modifications in antigenicity. We assessed the neutralizing capacity of antibodies to prevent cell infection, using a live virus neutralization test with different strains [19A (initial one), 20B (B.1.1.241 lineage), 20I/501Y.V1 (B.1.1.7 lineage), and 20H/501Y.V2 (B.1.351 lineage)] in serum samples collected from different populations: two-dose vaccinated COVID-19-naive healthcare workers (HCWs; Pfizer-BioNTech BNT161b2), 6-months post mild COVID-19 HCWs, and critical COVID-19 patients. No significant difference was observed between the 20B and 19A isolates for HCWs with mild COVID-19 and critical patients. However, a significant decrease in neutralization ability was found for 20I/501Y.V1 in comparison with 19A isolate for critical patients and HCWs 6-months post infection. Concerning 20H/501Y.V2, all populations had a significant reduction in neutralizing antibody titers in comparison with the 19A isolate. Interestingly, a significant difference in neutralization capacity was observed for vaccinated HCWs between the two variants but not in the convalescent groups.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/genética , Humanos , Testes de Neutralização , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
8.
Sci Immunol ; 6(59)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035116

RESUMO

Multiple Inflammatory Syndrome in Children (MIS-C) is a delayed and severe complication of SARS-CoV-2 infection that strikes previously healthy children. As MIS-C combines clinical features of Kawasaki disease and Toxic Shock Syndrome (TSS), we aimed to compare the immunological profile of pediatric patients with these different conditions. We analyzed blood cytokine expression, and the T cell repertoire and phenotype in 36 MIS-C cases, which were compared to 16 KD, 58 TSS, and 42 COVID-19 cases. We observed an increase of serum inflammatory cytokines (IL-6, IL-10, IL-18, TNF-α, IFNγ, CD25s, MCP1, IL-1RA) in MIS-C, TSS and KD, contrasting with low expression of HLA-DR in monocytes. We detected a specific expansion of activated T cells expressing the Vß21.3 T cell receptor ß chain variable region in both CD4 and CD8 subsets in 75% of MIS-C patients and not in any patient with TSS, KD, or acute COVID-19; this correlated with the cytokine storm detected. The T cell repertoire returned to baseline within weeks after MIS-C resolution. Vß21.3+ T cells from MIS-C patients expressed high levels of HLA-DR, CD38 and CX3CR1 but had weak responses to SARS-CoV-2 peptides in vitro. Consistently, the T cell expansion was not associated with specific classical HLA alleles. Thus, our data suggested that MIS-C is characterized by a polyclonal Vß21.3 T cell expansion not directed against SARS-CoV-2 antigenic peptides, which is not seen in KD, TSS and acute COVID-19.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , COVID-19/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Síndrome de Resposta Inflamatória Sistêmica/patologia , Adulto , Criança , Pré-Escolar , Citocinas/sangue , Antígenos HLA-DR/imunologia , Humanos , Ativação Linfocitária/imunologia , SARS-CoV-2/imunologia
9.
Ann Clin Transl Neurol ; 8(5): 1141-1150, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33830650

RESUMO

We compared SimoaTM and EllaTM immunoassays to assess serum neurofilament-light chain levels in 203 multiple sclerosis patients from the OFSEP HD study. There was a strong correlation (ρ = 0.86, p < 0.0001) between both platforms. The EllaTM instrument overestimated values by 17%, but as the data were linear (p = 0.57), it was possible to apply a correction factor to EllaTM results. As for SimoaTM , serum neurofilament-light chain levels measured by EllaTM were correlated with age and EDSS and were significantly higher in active multiple sclerosis, suggesting that these assays are equivalent and can be used in routine clinical practice.

10.
Clin Immunol ; 226: 108714, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33741504

RESUMO

Lipopolysaccharide (LPS) and monophosphoryl lipid A (MPLA) induce, overall, similar transcriptional profiles in healthy individuals, although LPS has been shown to more potently induce pro-inflammatory cytokines. We explore herein whether MPLA could be considered as a synthetic replacement of LPS in immune functional assays to study anergy of immune cells in septic patients. Ex vivo whole blood stimulation with MPLA revealed a lower induction of the TNFα secreted protein in 20 septic patients (SP) compared to 10 healthy volunteers (HV), in agreement with monocyte anergy. Principal component analysis of the 93-gene molecular response to MPLA and LPS stimulation found that the main variability was driven by stimulation in HV and by pathophysiology in SP. MPLA was a stronger inducer of the HLA family genes than LPS in both populations, arguing for divergent signalling pathways downstream of TLR-4. In addition, MPLA appeared to present a more informative stratification potential within the septic population.


Assuntos
Hospedeiro Imunocomprometido/imunologia , Lipídeo A/análogos & derivados , Lipopolissacarídeos/imunologia , Sepse/imunologia , Idoso , Idoso de 80 Anos ou mais , Citocinas/imunologia , Feminino , Humanos , Inflamação/imunologia , Lipídeo A/imunologia , Masculino , Monócitos/imunologia , Estudos Prospectivos , Transdução de Sinais/imunologia , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/imunologia
12.
Clin Chem ; 67(5): 742-752, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33399823

RESUMO

BACKGROUND: The association between SARS-CoV-2 commercial serological assays and virus neutralization test (VNT) has been poorly explored in mild patients with COVID-19. METHODS: 439 serum specimens were longitudinally collected from 76 healthcare workers with RT-PCR-confirmed COVID-19. The clinical sensitivity (determined weekly) of 9 commercial serological assays were evaluated. Clinical specificity was assessed using 69 pre-pandemic sera. Correlation, agreement, and concordance with the VNT were also assessed on a subset of 170 samples. Area under the ROC curve (AUC) was estimated at 2 neutralizing antibody titers. RESULTS: The Wantai Total Ab assay targeting the receptor binding domain (RBD) within the S protein presented the best sensitivity at different times during the course of disease. The clinical specificity was greater than 95% for all tests except for the Euroimmun IgA assay. The overall agreement with the presence of neutralizing antibodies ranged from 62.2% (95%CI; 56.0-68.1) for bioMérieux IgM to 91.2% (87.0-94.2) for Siemens. The lowest negative percent agreement (NPA) was found with the Wantai Total Ab assay (NPA 33% (21.1-48.3)). The NPA for other total Ab or IgG assays targeting the S or the RBD was 80.7% (66.7-89.7), 90.3% (78.1-96.1), and 96.8% (86.8-99.3) for Siemens, bioMérieux IgG, and DiaSorin, respectively. None of the commercial assays have sufficient performance to detect a neutralizing titer of 80 (AUC < 0.76). CONCLUSIONS: Although some assays show a better agreement with VNT than others, the present findings emphasize that commercialized serological tests, including those targeting the RBD, cannot substitute a VNT for the assessment of functional antibody response.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Adulto , Idoso , COVID-19/sangue , Teste Sorológico para COVID-19/métodos , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes de Neutralização , Estudos Prospectivos , SARS-CoV-2 , Sensibilidade e Especificidade
13.
Emerg Microbes Infect ; 10(1): 167-177, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33399033

RESUMO

During routine molecular surveillance of SARS-CoV-2 performed at the National Reference Center of Respiratory Viruses (Lyon, France) (n = 229 sequences collected February-April 2020), two frameshifting deletions were detected in the open reading frame 6, at the same position (27267). While a 26-nucleotide deletion variant (D26) was only found in one nasopharyngeal sample in March 2020, the 34-nucleotide deletion (D34) was found within a single geriatric hospital unit in 5/9 patients and one health care worker in April 2020. Phylogeny analysis strongly suggested a nosocomial transmission of D34, with potential fecal transmission, as also identified in a stool sample. No difference in disease severity was observed between patients hospitalized in the geriatric unit infected with WT or D34. In vitro D26 and D34 characterization revealed comparable replication kinetics with the wild-type (WT), but differential host immune responses. While interferon-stimulated genes were similarly upregulated after infection with WT and ORF6 variants, the latter specifically induced overexpression of 9 genes coding for inflammatory cytokines in the NF-kB pathway, including CCL2/MCP1, PTX3, and TNFα, for which high plasma levels have been associated with severe COVID-19. Our findings emphasize the need to monitor the occurrence of ORF6 deletions and assess their impact on the host immune response.


Assuntos
COVID-19/epidemiologia , Infecção Hospitalar/virologia , Variação Genética , Genoma Viral , SARS-CoV-2/genética , Proteínas Virais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , COVID-19/imunologia , COVID-19/virologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/imunologia , Citocinas/imunologia , Feminino , Mutação da Fase de Leitura , França/epidemiologia , Hospitalização , Humanos , Imunidade , Inflamação , Masculino , Filogenia , Deleção de Sequência , Proteínas Virais/imunologia
14.
Eur J Immunol ; 51(4): 989-994, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33314090

RESUMO

Low concentrations of type-I interferon (IFN) in blood seem to be associated with more severe forms of Coronavirus disease 2019 (COVID-19). However, following the type-I interferon response (IR) in early stage disease is a major challenge. We evaluated detection of a molecular interferon signature on a FilmArray® system, which includes PCR assays for four interferon stimulated genes. We analyzed three types of patient populations: (i) children admitted to a pediatric emergency unit for fever and suspected infection, (ii) ICU-admitted patients with severe COVID-19, and (iii) healthcare workers with mild COVID-19. The results were compared to the reference tools, that is, molecular signature assessed with Nanostring® and IFN-α2 quantification by SIMOA® (Single MOlecule Array). A strong correlation was observed between the IR measured by the FilmArray®, Nanostring®, and SIMOA® platforms (r-Spearman 0.996 and 0.838, respectively). The FilmArray® panel could be used in the COVID-19 pandemic to evaluate the IR in 45-min with 2 min hand-on-time at hospitalization and to monitor the IR in future clinical trials.


Assuntos
COVID-19/sangue , Interferon-alfa/sangue , Reação em Cadeia da Polimerase/métodos , SARS-CoV-2/imunologia , Adulto , Idoso , COVID-19/imunologia , Criança , Feminino , Pessoal de Saúde , Humanos , Interferon Tipo I/sangue , Interferon Tipo I/genética , Interferon-alfa/genética , Masculino
15.
BMJ Open ; 10(11): e041268, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33234651

RESUMO

INTRODUCTION: The COVID-19 pandemic caused by SARS-CoV-2 threatens global public health, and there is an urgent public health need to assess acquired immunity to SARS-CoV-2. Serological tests might provide results that can be complementary to or confirm suspected COVID-19 cases and reveal previous infection. The performance of serological assays (sensitivity and specificity) has to be evaluated before their use in the general population. The neutralisation capacity of the produced antibodies also has to be evaluated. METHODS AND ANALYSIS: We set up a prospective, multicentric clinical study to evaluate the performance of serological kits among a population of healthcare workers presenting mild symptoms suggestive of SARS-CoV-2 infection. Four hundred symptomatic healthcare workers will be included in the COVID-SER study. The values obtained from a control cohort included during the prepandemic time will be used as reference. A workflow was set up to study serological response to SARS-CoV-2 infection and to evaluate antibody neutralisation capacity in patients with a confirmed SARS-CoV-2 infection. The sensitivity and specificity of the tests will be assessed using molecular detection of the virus as a reference. The measurement of IgM and IgG antibodies will be performed once per week for 6 consecutive weeks and then at 6, 12, 18, 24 and 36 months after the diagnosis. The kinetics of IgM and IgG will determine the optimal period to perform serological testing. The proportion of false negative PCR tests in symptomatic subjects will be determined on the basis of subsequent seroconversions. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the national review board for biomedical research in April 2020 (Comité de Protection des Personnes Sud Méditerranée I, Marseille, France) (ID RCB 2020-A00932-37). Results will be disseminated through presentations at scientific meetings and publications in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04341142.


Assuntos
Anticorpos Antivirais/análise , COVID-19/diagnóstico , Programas de Rastreamento/métodos , Pandemias , SARS-CoV-2/imunologia , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Testes Sorológicos
16.
Viruses ; 12(11)2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187285

RESUMO

Torque teno virus (TTV) has been proposed as a surrogate biomarker of T-cell function in allogeneic-haematopoietic-stem-cell transplantation (allo-HSCT). Conflicting data exists regarding the value of TTV to assess the degree of immunosuppression. The aim of the present study was to investigate the correlation between TTV viral load and immune function. Using samples from a prospective cohort composed of healthy-volunteers (HV) and allo-HSCT recipients at 6 months post-transplantation, we assessed the correlation between TTV viraemia and immune cell counts or T-cell proliferation capacity post-phytohaemagglutinin stimulation. TTV viraemia was detected in 68% of HV (n = 80) and 100% of allo-HSCT recipients (n = 41; p < 0.001); it was significantly higher in allo-HSCT recipients (3.9 vs. 2.1 Log copies/mL, p < 0.001). There was no correlation between T-cell function and CD3+T-cell count (rho: 0.002) suggesting that T-cell count can normalise without full functional recovery. Furthermore, no significant correlation was observed between TTV viraemia and absolute total/subset lymphocyte counts (rho: <0.13). The highest correlation was observed between TTV viral load and T-cell proliferation capacity (rho: -0.39). We therefore report an inverse correlation between T-cell function and TTV viraemia that is independent of T-cell count. Monitoring of TTV viraemia could be a fast suitable option to objectively assess the competence of immune function in at-risk populations.


Assuntos
Biomarcadores/sangue , Infecções por Vírus de DNA/diagnóstico , Transplante de Células-Tronco Hematopoéticas , Imunossupressão , Torque teno virus/isolamento & purificação , Carga Viral , Adulto , Proliferação de Células , Infecções por Vírus de DNA/sangue , Infecções por Vírus de DNA/virologia , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Torque teno virus/crescimento & desenvolvimento , Viremia/sangue , Viremia/diagnóstico , Viremia/virologia
17.
Sci Rep ; 10(1): 16136, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999313

RESUMO

The complexity of sepsis pathophysiology hinders patient management and therapeutic decisions. In this proof-of-concept study we characterised the underlying host immune response alterations using a standardised immune functional assay (IFA) in order to stratify a sepsis population. In septic shock patients, ex vivo LPS and SEB stimulations modulated, respectively, 5.3% (1/19) and 57.1% (12/21) of the pathways modulated in healthy volunteers (HV), highlighting deeper alterations induced by LPS than by SEB. SEB-based clustering, identified 3 severity-based groups of septic patients significantly different regarding mHLA-DR expression and TNFα level post-LPS, as well as 28-day mortality, and nosocomial infections. Combining the results from two independent cohorts gathering 20 HV and 60 patients, 1 cluster grouped all HV with 12% of patients. The second cluster grouped 42% of patients and contained all non-survivors. The third cluster grouped 46% of patients, including 78% of those with nosocomial infections. The molecular features of these clusters indicated a distinctive contribution of previously described genes defining a "healthy-immune response" and a "sepsis-related host response". The third cluster was characterised by potential immune recovery that underlines the possible added value of SEB-based IFA to capture the sepsis immune response and contribute to personalised management.


Assuntos
Choque Séptico/classificação , Choque Séptico/patologia , Idoso , Biomarcadores/sangue , Infecção Hospitalar , Enterotoxinas/imunologia , Feminino , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Antígenos HLA-DR/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/normas , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Estudo de Prova de Conceito , Sepse/metabolismo , Choque Séptico/mortalidade , Fator de Necrose Tumoral alfa/metabolismo
18.
Science ; 370(6515)2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32972996

RESUMO

Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-ω (IFN-ω) (13 patients), against the 13 types of IFN-α (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men.


Assuntos
Autoanticorpos/sangue , Infecções por Coronavirus/imunologia , Interferon Tipo I/imunologia , Interferon alfa-2/imunologia , Pneumonia Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Infecções Assintomáticas , Betacoronavirus , COVID-19 , Estudos de Casos e Controles , Estado Terminal , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
19.
Cell Rep Med ; 1(4): 100059, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32835306

RESUMO

In the current COVID-19 pandemic context, proposing and validating effective treatments represents a major challenge. However, the scarcity of biologically relevant pre-clinical models of SARS-CoV-2 infection imposes a significant barrier for scientific and medical progress, including the rapid transition of potentially effective treatments to the clinical setting. We use reconstituted human airway epithelia to isolate and then characterize the viral infection kinetics, tissue-level remodeling of the cellular ultrastructure, and transcriptional early immune signatures induced by SARS-CoV-2 in a physiologically relevant model. Our results emphasize distinctive transcriptional immune signatures between nasal and bronchial HAE, both in terms of kinetics and intensity, hence suggesting putative intrinsic differences in the early response to SARS-CoV-2 infection. Most important, we provide evidence in human-derived tissues on the antiviral efficacy of remdesivir monotherapy and explore the potential of the remdesivir-diltiazem combination as an option worthy of further investigation to respond to the still-unmet COVID-19 medical need.

20.
Clin Chem ; 66(6): 802-808, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32359149

RESUMO

BACKGROUND: Fever is one of the leading causes of consultation in the pediatric emergency department for patients under the age of 3 years. Distinguishing between bacterial and viral infections etiologies in febrile patients remains challenging. We hypothesized that specific host biomarkers for viral infections, such as type I-interferon (IFN), could help clinicians' decisions and limit antibiotic overuse. METHODS: Paxgene tubes and serum were collected from febrile children (n = 101), age from 7 days to 36 months, with proven viral or bacterial infections, being treated at pediatric emergency departments in France. We assessed the performance of an IFN signature, which was based on quantification of expression of IFN-stimulated genes using the Nanostring® technology and plasma IFN-α quantified by digital ELISA technology. RESULTS: Serum concentrations of IFN-α were below the quantification threshold (30 fg/mL) for 2% (1/46) of children with proven viral infections and for 71% (39/55) of children with bacterial infections (P < 0.001). IFN-α concentrations and IFN score were significantly higher in viral compared to bacterial infection (P < 0.001). There was a strong correlation between serum IFN-α concentrations and IFN score (p-pearson = 0.83). Both serum IFN-α concentration and IFN score robustly discriminated (Area Under the Curve >0.91 for both) between viral and bacterial infection in febrile children, compared to C-reactive protein (0.83). CONCLUSIONS: IFN-α is increased in blood of febrile infants with viral infections. The discriminative performance of IFN-α femtomolar concentrations as well as blood transcriptional signatures could show a diagnostic benefit and potentially limit antibiotic overuse. CLINICAL TRIALS REGISTRATION: clinicaltrials.gov (NCT03163628).


Assuntos
Infecções Bacterianas/diagnóstico , Interferon Tipo I/sangue , Viroses/diagnóstico , Biomarcadores/sangue , Pré-Escolar , Diagnóstico Diferencial , Serviço Hospitalar de Emergência , Feminino , Febre , Humanos , Lactente , Recém-Nascido , Masculino , Medicina de Emergência Pediátrica/métodos , Medicina de Emergência Pediátrica/organização & administração , Estudos Prospectivos
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