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1.
Front Immunol ; 14: 1107438, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006279

RESUMO

Background: The rate of seroconversion after COVID-19 vaccination in patients with moderate to severe psoriasis requiring systemic treatment is poorly understood. Objectives: The aim of this prospective single-center cohort study performed between May 2020 and October 2021 was to determine the rate of seroconversion after COVID-19 vaccination in patients under active systemic treatment for moderate to severe psoriasis. Methods: Inclusion criteria were systemic treatment for moderate to severe psoriasis, known COVID-19 vaccination status, and repetitive anti-SARS-CoV-2-S IgG serum quantification. The primary outcome was the rate of anti-SARS-CoV-2-S IgG seroconversion after complete COVID-19 vaccination. Results: 77 patients with a median age of 55.9 years undergoing systemic treatment for moderate to severe psoriasis were included. The majority of patients received interleukin- (n=50, 64.9%) or tumor necrosis factor (TNF)-α inhibitors (n=16, 20.8%) as systemic treatment for psoriasis; nine patients (11.7%) were treated with methotrexate (MTX) monotherapy, and one patient each received dimethyl fumarate (1.3%), respectively apremilast (1.3%). All included patients completed COVID-19 vaccination with two doses over the course of the study. Serum testing revealed that 74 patients (96.1%) showed an anti-SARS-CoV-2-S IgG seroconversion. While all patients on IL-17A, -12 or -12/23 inhibitors (n=50) achieved seroconversion, three of 16 patients (18.8%) receiving MTX and/or a TNF-α inhibitor as main anti-psoriatic treatment did not. At follow-up, none of the patients had developed symptomatic COVID-19 or died from COVID-19. Conclusions: Anti-SARS-CoV-2-S IgG seroconversion rates following COVID-19 vaccination in psoriasis patients under systemic treatment were high. An impaired serological response, however, was observed in patients receiving MTX and/or TNF-α inhibitors, in particular infliximab.


Assuntos
COVID-19 , Psoríase , Humanos , Pessoa de Meia-Idade , Vacinas contra COVID-19 , Estudos de Coortes , Estudos Prospectivos , Fator de Necrose Tumoral alfa , COVID-19/prevenção & controle , Psoríase/tratamento farmacológico , Metotrexato , Anticorpos Antivirais , Imunoglobulina G
2.
Front Oncol ; 12: 879876, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091146

RESUMO

Background: COVID-19 vaccination reduces risk of SARS-CoV-2 infection, COVID-19 severity and death. However, the rate of seroconversion after COVID-19 vaccination in cancer patients requiring systemic anticancer treatment is poorly investigated. The aim of the present study was to determine the rate of seroconversion after COVID-19 vaccination in advanced skin cancer patients under active systemic anticancer treatment. Methods: This prospective single-center study of a consecutive sample of advanced skin cancer patients was performed from May 2020 until October 2021. Inclusion criteria were systemic treatment for advanced skin cancer, known COVID-19 vaccination status, repetitive anti-SARS-CoV-2-S IgG serum quantification and first and second COVID-19 vaccination. Primary outcome was the rate of anti-SARS-CoV-2-S IgG seroconversion after complete COVID-19 vaccination. Results: Of 60 patients with advanced skin cancers, 52 patients (86.7%) received immune checkpoint inhibition (ICI), seven (11.7%) targeted agents (TT), one (1.7%) chemotherapy. Median follow-up time was 12.7 months. During study progress ten patients had died from skin cancer prior to vaccination completion, six patients were lost to follow-up and three patients had refused vaccination. 41 patients completed COVID-19 vaccination with two doses and known serological status. Of those, serum testing revealed n=3 patients (7.3%) as anti-SARS-CoV-2-S IgG positive prior to vaccination, n=32 patients (78.0%) showed a seroconversion, n=6 patients (14.6%) did not achieve a seroconversion. Patients failing serological response were immunocompromised due to concomitant hematological malignancy, previous chemotherapy or autoimmune disease requiring immunosuppressive comedications. Immunosuppressive comedication due to severe adverse events of ICI therapy did not impair seroconversion following COVID-19 vaccination. Of 41 completely vaccinated patients, 35 (85.4%) were under treatment with ICI, five (12.2%) with TT, and one (2.4%) with chemotherapy. 27 patients (65.9%) were treated non adjuvantly. Of these patients, 13 patients had achieved objective response (complete/partial response) as best tumor response (48.2%). Conclusion and relevance: Rate of anti-SARS-CoV-2-S IgG seroconversion in advanced skin cancer patients under systemic anticancer treatment after complete COVID-19 vaccination is comparable to other cancer entities. An impaired serological response was observed in patients who were immunocompromised due to concomitant diseases or previous chemotherapies. Immunosuppressive comedication due to severe adverse events of ICI did not impair the serological response to COVID-19 vaccination.

3.
Neurol Neurochir Pol ; 56(3): 236-245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35726751

RESUMO

INTRODUCTION: Fatigue is the most frequent symptom in multiple sclerosis (MS), although it is still poorly understood due to its complexity and subjective nature. There is an urgent need to identify reliable biomarkers to improve disease prognosis and therapeutic strategies. Epstein-Barr virus (EBV) is the major environmental risk factor associated with MS aetiology, and trials with EBV-targeted T cell therapies have reduced fatigue severity in MS patients. AIM OF THE STUDY: We investigated whether the serum amount of immunoglobulin (Ig)G-specific for EBV antigens could be a suitable prognostic marker for the assessment of MS-related fatigue. MATERIAL AND METHODS: A total of 194 MS patients were enrolled. We quantified EBV nuclear antigen 1 (EBNA1) and EBV viral capsid antigen (VCA) immunoglobulin (Ig) G levels and B cell-activating factor of the tumour necrosis factor family (BAFF) concentration in the serum of patients with relapsing-remitting MS (RRMS) and chronic progressive MS (CPMS), and we analysed their correlation with aspects of fatigue and other clinical disease parameters. RESULTS: A complete EBV seropositivity could be detected in our cohort. After adjusting for confounding variables and covariates, neither EBNA1 nor VCA antibody titres were associated with levels of fatigue, sleepiness, depression, or with any of the clinical values such as expanded disability status scale, lesion count, annual relapse rate, or disease duration. However, patients with RRMS had significantly higher EBNA1 IgG titre than those with CPMS, whereas this was not the case under therapies targeting CD20+ cells. BAFF levels in serum were inversely proportional to anti-EBNA1 IgG. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our results show that EBNA1 IgG titre is not associated with the presence or level of fatigue. Whether the increased EBNA1 titre in RRMS plays a direct role in disease progression, or is only a consequence of excessive B cell activation, remains to be answered in future studies.


Assuntos
Anticorpos Antivirais , Infecções por Vírus Epstein-Barr , Fadiga , Imunoglobulina G , Esclerose Múltipla , Anticorpos Antivirais/sangue , Infecções por Vírus Epstein-Barr/complicações , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Fadiga/complicações , Herpesvirus Humano 4 , Humanos , Imunoglobulina G/sangue , Esclerose Múltipla/complicações , Esclerose Múltipla/virologia
4.
PLoS Negl Trop Dis ; 16(5): e0010425, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35536867

RESUMO

Neutralizing antibodies (nAbs) prevent the entry of viruses into permissive cells. Since nAbs represent correlates of protection against the Rabies lyssavirus, the presence of sufficient nAbs indicates effective vaccination. Accordingly, Rabies lyssavirus-specific nAb titers need to be determined in routine diagnostics to identify individuals being at risk of Rabies lyssavirus infections due to insufficient immunity. The current gold standard for the quantification of Rabies lyssavirus-specific nAbs is the rapid fluorescent focus inhibition test (RFFIT). However, RFFITs are expensive and labor-intensive since multiple microplate wells must be evaluated one-by-one by trained personnel through microscopic inspection, which limits the number of samples that can be processed. To overcome this disadvantage, we established a novel assay for Rabies lyssavirus-specific nAbs relying on an in-cell-ELISA (icELISA)-based neutralization test (icNT). The icNT differs from the RFFIT in the readout phase, and can be automatically quantified in minutes using broadly available microplate readers. During the establishment, icNT parameters such as antibody concentrations, permeabilization procedures, blocking reagents, infectious doses, and the duration of infection were optimized. Afterwards, a dose-dependent detection of Rabies lyssavirus neutralization was demonstrated using the WHO Standard Rabies Immunoglobulin reference. A panel of 200 sera with known RFFIT titers revealed very good sensitivity and specificity of the icNT. Furthermore, the icNT showed very good intra- and inter-assay precision. By recognizing Rabies lyssavirus-specific antigens, the assay can be applied immediately to automatically quantify the concentration of Rabies lyssavirus nAbs in routine diagnostics or for various basic research questions such as screening for antiviral compounds.


Assuntos
Lyssavirus , Vacina Antirrábica , Vírus da Raiva , Raiva , Anticorpos Neutralizantes , Anticorpos Antivirais , Antígenos Virais , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Testes de Neutralização/métodos , Raiva/prevenção & controle
5.
Vaccines (Basel) ; 10(2)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35214596

RESUMO

Hepatitis B virus infection results in the appearance of anti-HBc antibodies that normally persist lifelong. We analyzed the course of anti-HBc antibodies overtime, focusing on patients with a permanent loss or fluctuating anti-HBc antibodies. From 120,531 patients tested for anti-HBc antibodies (Architect, Abbott) from January 2006 to December 2020, ≥4 serial values were available in 8098 and permanent or intermittent anti-HBc loss was observed in 139 patients. It was relatively frequent in baseline anti-HBc positive, immunocompromised patients with available serial measurements of anti-HBc overtime (13% of hematologic/oncologic patients, 10% of solid organ transplant recipients, and 6% of HIV patients compared to 3% in patients with other diseases). In the same period, 12,607 samples were tested for HBsAg, anti-HBc antibodies, and HBV DNA-in nine cases we detected HBV DNA with undetectable anti-HBc and HBsAg. In four out of nine cases contamination of the PCR during processing was the likeliest cause, in another four, no further data were available, while in one the HBV DNA was later followed by a temporary anti-HBc seroconversion. In conclusion, permanent or intermittent anti-HBc loss is more common in immunocompromised hosts than in patients with other underlying diseases. Furthermore, anti-HBc and HBsAg assays can be safely used to exclude an active HBV infection, even in immunocompromised hosts.

6.
J Med Virol ; 94(3): 951-957, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34633099

RESUMO

During the first wave of the pandemic, we compared the occurrence of subjectively experienced COVID-19-like symptoms and true severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroconversion rates among medical personnel in general practices. This cross-sectional study determined the SARS-CoV-2-specific immunoglobulin G (IgG) antibody status of medical staff from 100 outpatient practices in Germany. Study cohort characteristics and COVID-19-like symptoms were obtained by questionnaires. The initial screening for SARS-CoV-2-recognizing antibodies was performed using a commercial chemiluminescence microparticle immunoassay. Positive results were controlled with another approved test. Samples with discrepant results were subjected to a third IgG-binding assay and a neutralization test. A total of 861 participants were included, 1.7% (n = 15) of whom tested positive for SARS-CoV-specific IgG in the initial screening test. In 46.6% (n = 7) of positive cases, test results were confirmed by an independent test. In the eight samples with discrepant results, neither spike-specific antibodies nor in vitro neutralizing capacity were detectable, resulting in a genuine seroprevalence rate of 0.8%. 794 participants completed the questionnaire. Intriguingly, a total of 53.7% (n = 426) of them stated episodes of COVID-19-like symptoms. Except for smell and taste dysfunction, there were no significant differences between the groups with and without laboratory-confirmed SARS-CoV-2 seroconversion. Our results demonstrated that only 0.8% of participants acquired SARS-CoV-2 even though 53.7% of participants reportedly experienced COVID-19-like symptoms. Thus, even among medical staff, self-diagnosis based on subjectively experienced symptoms does not have a relevant predictive value.


Assuntos
COVID-19 , Anticorpos Antivirais , COVID-19/diagnóstico , COVID-19/epidemiologia , Estudos Transversais , Pessoal de Saúde , Humanos , Imunoglobulina G , SARS-CoV-2 , Soroconversão , Estudos Soroepidemiológicos
7.
Pathogens ; 10(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073618

RESUMO

We aimed to evaluate the LIAISON® SARS-CoV-2 antigen assay (DiaSorin), comparing its performance to real-time polymerase chain reaction (RT-PCR) for the detection of SARS-CoV-2 RNA. 182 (110 PCR-positive and 72 PCR-negative) nasopharyngeal swab samples were taken for the detection of SARS-CoV-2. RT-PCR and antigen assay were performed using the same material. The sensitivity and specificity of the antigen assay were calculated for different cut-offs, with RT-PCR serving as the reference method. Stored clinical samples that were positive for other respiratory viruses were tested to evaluate cross-reactivity. One third (33/110, 30%) were falsely classified as negative, while no false positives were found using the 200 TCID50/mL cut-off for the SARS-CoV-2 antigen as proposed by the manufacturer. This corresponded to a sensitivity of 70% (60-78%) and a specificity of 100% (94-100%). Lowering the cut-off for positivity of the antigen assay to 22.79 or 57.68 TCID50/mL increased the sensitivity of the method, reaching a sensitivity of 92% (85-96%) vs. 79% (70-86%) and a specificity of 81% (69-89%) vs. 99% (91-100%), respectively. The antigen assay reliably detected samples with high SARS-CoV-2 viral loads (≥106 copies SARS-CoV-2/mL), while it cannot differentiate between negative and low positive samples. Cross-reactivity toward other respiratory viruses was not detected.

8.
Ther Adv Neurol Disord ; 14: 1756286421993701, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33737955

RESUMO

BACKGROUND: A growing number of reports suggest that infection with SARS-CoV-2 often leads to neurological involvement; however, data on the incidence and severity are limited to mainly case reports and retrospective studies. METHODS: This prospective, cross-sectional study of 102 SARS-CoV-2 PCR positive patients investigated the frequency, type, severity and risk factors as well as underlying pathophysiological mechanisms of neurological involvement (NIV) in COVID-19 patients. RESULTS: Across the cohort, 59.8% of patients had NIV. Unspecific NIV was suffered by 24.5%, mainly general weakness and cognitive decline or delirium. Mild NIV was found in 9.8%; most commonly, impaired taste or smell. Severe NIV was present in 23.5%; half of these suffered cerebral ischaemia. Incidence of NIV increased with respiratory symptoms of COVID-19. Mortality was higher with increasing NIV severity. Notably, 83.3% with severe NIV had a pre-existing neurological co-morbidity. All cerebrospinal fluid (CSF) samples were negative for SARS-CoV-2 RNA, and SARS-CoV-2 antibody quotient did not suggest intrathecal antibody synthesis. Of the patients with severe NIV, 50% had blood-brain barrier (BBB) disruption and showed a trend of elevated interleukin levels in CSF. Antibodies against neuronal and glial epitopes were detected in 35% of the patients tested. CONCLUSION: Cerebrovascular events were the most frequent severe NIV and severe NIV was associated with high mortality. Incidence of NIV increased with respiratory symptoms and NIV and pre-existing neurological morbidities were independent risk factors for fatality. Inflammatory involvement due to BBB disruption and cytokine release drives NIV, rather than direct viral invasion. These findings might help physicians define a further patient group requiring particular attention during the pandemic.

9.
Transplantation ; 105(12): 2655-2660, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33660657

RESUMO

BACKGROUND: Norovirus (NoV) infection frequently progresses to chronic disease after kidney transplant (KTx). This study aims to assess potential risk factors helping to determine patients at risk of chronic NoV infection and to analyze the effect of NoV on allograft outcome. Additionally, we assessed the effectiveness of intravenous immunoglobulin (IVIg) therapy for chronic NoV infection. METHODS: The study enrolled 60 KTx patients requiring hospitalization because of NoV infection. Clinical parameters, severity of NoV infection and potential risk factors were evaluated. Outcome parameters were clinical symptoms, rehospitalizations, persistent shedding of virus, and effects on allograft function. RESULTS: Patients were divided into 2 groups: 29 had acute NoV infection only, 31 progressed to chronic NoV infection. Chronic NoV infection was defined as a recurrence of clinical symptoms plus redetection of NoV in stool. Lymphocyte-depleting induction therapy and diabetes mellitus were independent risk factors for chronic infection. For patients with chronic NoV infection, length of stay in hospital was significantly prolonged (P = 0.024). Allograft function remained impaired in the chronic NoV group 6 and 12 mo after initial admission. IVIg was administered to 18 patients with chronic NoV infection. No further clinical symptoms of NoV infection occurred in 13 (72%) of these patients. However, NoV was still detectable in stool specimens from 10 (77%) of these patients. CONCLUSIONS: Chronic NoV infection is associated with reduced allograft function. Administration of IVIg to patients with chronic NoV infection seems beneficial in achieving freedom from clinical symptoms, despite limited effects on shedding of virus.


Assuntos
Infecções por Caliciviridae , Transplante de Rim , Norovirus , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/epidemiologia , Humanos , Transplante de Rim/efeitos adversos , Transplantados , Transplante Homólogo/efeitos adversos
10.
Vaccines (Basel) ; 9(2)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33504093

RESUMO

To estimate protection from cytomegalovirus (CMV) replication after solid organ transplantation, CMV serology has been considered insufficient and thus CMV immunity is increasingly assessed by cellular in vitro methods. We compared two commercially available IFN-γ ELISpot assays (T-Track CMV and T-SPOT.CMV) and an IFN-γ ELISA (QuantiFERON-CMV). Currently, there is no study comparing these three assays. The assays were performed in 56 liver transplant recipients at the end of antiviral prophylaxis and one month thereafter. In CMV high- or intermediate-risk patients the two ELISpot assays showed significant correlation (p < 0.0001, r > 0.6) but the correlation of the ELISpot assays with QuantiFERON-CMV was weaker. Results of both ELISpot assays were similarly predictive of protection from CMV-DNAemia ≥500 copies/mL [CMV pp65 T-SPOT.CMV at the end of prophylaxis: area under curve (AUC) = 0.744, cut-off 142 spot forming units (SFU), sensitivity set to 100%, specificity 46%; CMV IE-1 T-Track CMV at month 1: AUC = 0.762, cut-off 3.5 SFU, sensitivity set to 100%, specificity 59%]. The QuantiFERON-CMV assay was inferior, reaching a specificity of 23% when setting the sensitivity to 100%. In conclusion, both CMV-specific ELISpot assays appear suitable to assess protection from CMV infection/reactivation in liver transplant recipients.

11.
J Med Virol ; 93(6): 3955-3959, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32880994

RESUMO

Data about the diagnostic efficiency of bilateral bronchoalveolar lavage (BAL) samples and endotracheal aspirates (EA) testing for common viral respiratory infections are scarce. We analyzed data from 167 cases, where bilateral BAL samples were tested, and from 101 cases, where BAL samples and EA were tested. Multiplex polymerase chain reaction (PCR) was performed with the fast track diagnostics viral respiratory panel, producing data on the adenovirus, coronavirus, enterovirus, human metapneumovirus, bocavirus, influenza virus, parainfluenza virus, rhinovirus, and respiratory syncytial virus status of patients with respiratory disease symptoms. In the bilateral BAL cohort, 46 (27.5%) cases were positive for at least one of the viruses mentioned above in both samples. Discrepant results (virus not detected on one side) were seen in six (3.6%) cases. In the BAL versus EA cohort, 12 (11.9%) cases were positive in both materials, discrepant results (only one material being positive) were observed in 11 (10.9%) cases, with seven (63.6%) BAL samples, and four (36.4%) EA being positive. Bilateral sampling does not significantly improve the diagnostic efficiency of BAL for the detection of common respiratory viral pathogens via PCR. The diagnostic quality of EA and BAL samples for the detection of common viral respiratory pathogens is comparable.


Assuntos
Lavagem Broncoalveolar/métodos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Viroses/diagnóstico , Viroses/virologia , Adulto , Idoso , Estudos de Coortes , Coronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex/métodos
12.
Transpl Infect Dis ; 21(3): e13088, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30929308

RESUMO

BACKGROUND: Hepatitis E virus (HEV) genotype 3 infection frequently progresses to chronic disease with persisting HEV viremia in immunocompromised patients. Here, we evaluated the prevalence of HEV infection in renal allograft recipients and investigated the efficacy and tolerability of ribavirin monotherapy. METHODS: A total of 947 recipients on average 8.7 years post transplant were screened for anti-HEV IgG, IgM and HEV-RNA. Sixteen HEV-viremic renal allograft recipients were treated with ribavirin for 12 weeks. HEV-RNA concentration, laboratory and clinical parameters were assessed at baseline, during therapy and 12 weeks after treatment cessation. HEV-genotyping was performed in all HEV-viremic patients. RESULTS: Past HEV infection was detected serologically in 18% of the renal allograft recipients. Ongoing HEV replication was found in 16 recipients (all genotype 3). Unanimously, distinct HEV sequences were revealed in all HEV-viremic patients. At the start of ribavirin treatment, median HEV-RNA viral load was 4.3 × 106 (8000-5.0 × 106 ) IU/mL. Ninety-four percentage of HEV-infected allograft recipients showed a sustained virological response 12 weeks after treatment cessation. Ribavirin treatment was associated with rapid decrease in liver enzymes and rare occurrence of anemia. CONCLUSIONS: Prevalence of active HEV infection is important in renal transplant patients without signs of nosocomial infection. Ribavirin treatment was safe and effective.


Assuntos
Antivirais/uso terapêutico , Anticorpos Anti-Hepatite/sangue , Hepatite E/tratamento farmacológico , Transplante de Rim , Ribavirina/uso terapêutico , Adulto , Idoso , Aloenxertos , Feminino , Genótipo , Hepatite E/epidemiologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , RNA Viral/sangue , Transplante Homólogo , Adulto Jovem
13.
J Clin Virol ; 105: 91-96, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29936407

RESUMO

BACKGROUND: Assays detecting CMV-specific cell-mediated immunity (CMI) may support the current management of CMV infection in solid-organ transplant (SOT) recipients, by allowing a better risk assessment and adjusting antiviral treatment. OBJECTIVES: The primary endpoint was the performance of two tests measuring CMV-specific interferon-gamma production, both approved for commercial use in clinical settings. Secondarily, we determined a cut-off for the cellular immune response, which protects against CMV reactivation/infection. STUDY DESIGN: Thirty kidney transplant (KTx) patients were stratified according to their CMV-IgG status pre-transplantation (Tx) and were divided into two groups: pre-emptive (donor-/recipient+, donor+/recipient+) and prophylaxis (donor+/recipient-). An ELISpot (T-Track-CMV) was performed at month 1 post-Tx (pre-emptive group) and end of prophylaxis and one month thereafter (prophylaxis group). An ELISA (QuantiFERON-CMV) was performed every 2-4 weeks (pre-emptive) or monthly (prophylaxis), in parallel to the CMV viral load (PCR). RESULTS: A good positive agreement was obtained between the QuantiFERON-CMV or T-Track-CMV and the CMV-IgG (kappa = 0.839 and 0.824, respectively). A cut-off of 19.5 spot forming units (SFU)/200,000 lymphocytes for the T-Track-CMV IE-1 (AUC = 0.802, sensitivity 45%, specificity 100%) and 495 SFU/200,000 lymphocytes for the T-Track-CMV pp65 (AUC = 0.617, sensitivity 11%, specificity 100%) was defined to assess protection against reactivation. The QuantiFERON-CMV performed modestly (AUC = 0.477, cut-off 85.1 IU/ml). CONCLUSIONS: The QuantiFERON-CMV and T-Track-CMV enable the functional assessment of CMV-specific CMI in KTx recipients. In combination with CMV viral load monitoring, T-Track-CMV results could stratify patients at risk of CMV reactivation/infection.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Imunoensaio/métodos , Interferon gama/sangue , Transplantados , Ativação Viral/imunologia , Adulto , Idoso , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/imunologia , ELISPOT , Feminino , Humanos , Imunidade Celular , Imunoensaio/normas , Interferon gama/biossíntese , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
15.
J Virol ; 92(13)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29669837

RESUMO

Virus-specific CD8 T cell response seems to play a significant role in the outcome of hepatitis delta virus (HDV) infection. However, the HDV-specific T cell epitope repertoire and mechanisms of CD8 T cell failure in HDV infection have been poorly characterized. We therefore aimed to characterize HDV-specific CD8 T cell epitopes and the impacts of viral mutations on immune escape. In this study, we predicted peptide epitopes binding the most frequent human leukocyte antigen (HLA) types and assessed their HLA binding capacities. These epitopes were characterized in HDV-infected patients by intracellular gamma interferon (IFN-γ) staining. Sequence analysis of large hepatitis delta antigen (L-HDAg) and HLA typing were performed in 104 patients. The impacts of substitutions within epitopes on the CD8 T cell response were evaluated experimentally and by in silico studies. We identified two HLA-B*27-restricted CD8 T cell epitopes within L-HDAg. These novel epitopes are located in a relatively conserved region of L-HDAg. However, we detected molecular footprints within the epitopes in HLA-B*27-positive patients with chronic HDV infections. The variant peptides were not cross-recognized in HLA-B*27-positive patients with resolved HDV infections, indicating that the substitutions represent viral escape mutations. Molecular modeling of HLA-B*27 complexes with the L-HDAg epitope and its potential viral escape mutations indicated that the structural and electrostatic properties of the bound peptides differ considerably at the T cell receptor interface, which provides a possible molecular explanation for the escape mechanism. This viral escape from the HLA-B*27-restricted CD8 T cell response correlates with a chronic outcome of hepatitis D infection. T cell failure resulting from immune escape may contribute to the high chronicity rate in HDV infection.IMPORTANCE Hepatitis delta virus (HDV) causes severe chronic hepatitis, which affects 20 million people worldwide. Only a small number of patients are able to clear the virus, possibly mediated by a virus-specific T cell response. Here, we performed a systematic screen to define CD8 epitopes and investigated the role of CD8 T cells in the outcome of hepatitis delta and how they fail to eliminate HDV. Overall the number of epitopes identified was very low compared to other hepatotropic viruses. We identified, two HLA-B*27-restricted epitopes in patients with resolved infections. In HLA-B*27-positive patients with chronic HDV infections, however, we detected escape mutations within these identified epitopes that could lead to viral evasion of immune responses. These findings support evidence showing that HLA-B*27 is important for virus-specific CD8 T cell responses, similar to other viral infections. These results have implications for the clinical prognosis of HDV infection and for vaccine development.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Antígenos HLA-B/imunologia , Hepatite D/imunologia , Vírus Delta da Hepatite/imunologia , Antígenos da Hepatite delta/imunologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Linfócitos T CD8-Positivos/metabolismo , Epitopos de Linfócito T/metabolismo , Antígenos HLA-B/genética , Antígenos HLA-B/metabolismo , Hepatite D/genética , Hepatite D/virologia , Vírus Delta da Hepatite/genética , Antígenos da Hepatite delta/metabolismo , Humanos , Mutação , Homologia de Sequência
16.
Biol Blood Marrow Transplant ; 24(8): 1707-1714, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29550627

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients frequently develop acute respiratory failure (ARF) with pulmonary infiltrates. Molecular- and biomarker-based assays enhance pathogen detection, but data on their yield in this population are scarce. This was a retrospective single-center study of 156 consecutive HSCT recipients admitted to the intensive care unit (ICU) between May 2013 and July 2017. Findings from a microbiologic diagnostic workup using currently available methods on bronchoalveolar lavage (BAL) and blood samples from 66 patients (age, 58 years [range, 45 to 64]; HSCT to ICU, 176 days [range, 85 to 407]) with ARF and pulmonary infiltrates were analyzed. In 47 patients (71%) a causative pathogen was identified (fungal, n = 28; viral, n = 26; bacterial, n = 18). Polymicrobial findings involving several pathogen groups occurred in 20 patients (30%). Culture (12/16, 75%), galactomannan (13/15, 87%), and Aspergillus-PCR (8/9, 89%) from BAL but not serum galactomannan (6/14, 43%) helped to diagnose invasive aspergillosis (n = 16, 24%). Aspergillus-PCR detected azole resistance in 2 cases. Mucorales was found in 7 patients (11%; BAL culture, n = 6; Mucorales-PCR, n = 1). Patients with identified pathogens had higher Simplified Acute Physiology Score II scores (P = .049) and inferior ICU survival (6% versus 37%, P < .01), which largely related to the presence of an invasive fungal infection. Eight patients (12%) had 1 or more viruses with uncertain lung pathogenicity as the sole microbiologic finding. A diagnostic microbiologic workup incorporating molecular- and biomarker-based assays identified pathogens in most HSCT recipients with ARF and pulmonary infiltrates admitted to the ICU. Implications of polymicrobial infection and pathogen patterns in these patients warrant further investigation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/microbiologia , Doença Aguda , Aloenxertos , Aspergillus/isolamento & purificação , Sangue/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Transmissão de Doença Infecciosa , Humanos , Unidades de Terapia Intensiva , Pessoa de Meia-Idade , Mucorales/isolamento & purificação , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Transplantados
17.
J Clin Virol ; 99-100: 61-66, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29331844

RESUMO

BACKGROUND: CMV reactivation is a major cause of severe complications in allogeneic hematopoietic stem cell transplant (HSCT) recipients. The risk of CMV reactivation depends on the serostatus (+/-) of the donor (D) and recipient (R). The reconstitution of CMV-specific T-cell responses after transplantation is crucial for the control of CMV reactivation. OBJECTIVES: The study aimed to determine the cellular immune status correlating with protection from high-level CMV viremia (>5000 copies/ml) and disease. STUDY DESIGN: We monitored CMV-specific cellular immune responses in 9 high-risk (D-/R+), 14 intermediate risk (D+/R+) and 3 low risk individuals (D+/R-), and 8 CMV negative controls (D-/R-). Interferon- γ (IFN-γ) levels as a marker for the CD8+ T-cell response were determined by the QuantiFERON-CMV-assay and compared to viral loads determined by PCR. RESULTS: Early CMV reactivation was detected in all high-risk and 13/14 intermediate risk individuals. High-level viremia was detected in 5/7 high and 7/14 intermediate risk patients. Reconstitution of the CMV-specific cellular immune response started from 3 months after transplantation and resulted in protection against CMV reactivation. Re-establishing of CMV-specific T-cell immune responses with IFN- γ levels >8.9 IU/ml is crucial for protection from high-level CMV viremia. CONCLUSIONS: Monitoring of HSCT-recipients with the QuantiFERON-CMV-assay might be of great benefit to optimize antiviral treatment.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunoensaio , Reação em Cadeia da Polimerase em Tempo Real , Viremia/diagnóstico , Ativação Viral/imunologia , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/imunologia , DNA Viral/sangue , Feminino , Alemanha , Humanos , Imunidade Celular , Imunoensaio/normas , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Reação em Cadeia da Polimerase em Tempo Real/normas , Doadores de Tecidos , Transplantados , Carga Viral , Viremia/imunologia , Adulto Jovem
18.
Kidney Int Rep ; 2(1): 53-59, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29142940

RESUMO

INTRODUCTION: Because of the shortage of available organs for renal transplantation, strategies enabling the safe use of organs from donors with potential chronic infections such as hepatitis C are necessary. The aim of this study was to analyze the outcome of renal transplant donation from hepatitis C virus (HCV)-positive donors. METHODS: Between September 2002 and May 2007, 51 kidneys (34 donors) reactive for HCV antibodies were further evaluated. Six kidneys (5 donors) were transplanted to 6 recipients with known chronic HCV infection. The remaining 29 donors underwent extended virological testing. Nine donors were HCV RNA positive and thus not suitable for HCV-negative patients. Twenty donors (21 kidneys) did not have detectable HCV RNA copies and were transplanted into 21 HCV-negative recipients. Clinical outcomes focusing on safety, allograft function, and de novo HCV infection in the recipient were collected. RESULTS: There were no de novo HCV infections detected in recipients who were HCV negative before transplantation. The extended virological donor screening did not have an impact on median cold ischemia time. Five-year graft survival was 75%. DISCUSSION: Organs from anti-HCV-reactive, nonviremic donors can be transplanted safely to HCV-negative recipients.

19.
Eur J Cancer ; 86: 248-256, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29055840

RESUMO

OBJECTIVES: Immune checkpoint inhibitors can cause severe immune-related adverse events, with immune-related diarrhea and colitis (irColitis) being among the most frequent ones. While the majority of patients with irColitis respond well to corticosteroid treatment ± other immunomodulatory drugs such as infliximab, some patients do not show resolution of their symptoms. In the present study, we analysed the frequency of therapy-refractory irColitis, the underlying cause, and useful diagnostic approaches. METHODS: Between 2006 and 2016, 370 patients with metastatic malignant melanoma were treated with checkpoint inhibitors at the Department of Dermatology at the University Hospital Essen. All patients were identified for whom diarrhea and/or colitis was documented in the digital patient records. Patients who did not respond to standard immunosuppressive therapy within 2 weeks were classified as refractory. Demographic and clinical data of all patients were collected. RESULTS: We identified 41 patients with irColitis, the majority occurring during treatment with ipilimumab. Amongst these, 5 (12.2%) were refractory to standard immunomodulatory treatment with corticosteroids and infliximab. Therapy-refractory cases tended to show more severe inflammation in colonic biopsies (p = 0.04). In all therapy-refractory cases cytomegalovirus (CMV) was detectable. CMV-DNA in colonic biopsies and in plasma was significantly more often detectable in therapy-refractory cases (in colonic biopsies p = 0.005, in plasma: p = 0.002). Presence of serum CMV IgM and positive immunohistochemical stainings of colon biopsies for CMV were also associated with refractory colitis (p=0.021; p = 0.053). CONCLUSIONS: This report on CMV reactivation during management of checkpoint inhibitor-induced colitis emphasises the need for repetitive diagnostic measures in treatment-refractory irColitis.


Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Colite/virologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/patogenicidade , Melanoma/tratamento farmacológico , Infecções Oportunistas/virologia , Neoplasias Cutâneas/tratamento farmacológico , Ativação Viral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Antivirais/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/imunologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Citomegalovirus/imunologia , Infecções por Citomegalovirus/induzido quimicamente , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/imunologia , DNA Viral/genética , Feminino , Ganciclovir/uso terapêutico , Alemanha , Hospitais Universitários , Interações Hospedeiro-Patógeno , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Masculino , Melanoma/imunologia , Melanoma/secundário , Pessoa de Meia-Idade , Infecções Oportunistas/induzido quimicamente , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/imunologia , Valor Preditivo dos Testes , Fatores de Risco , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Fatores de Tempo , Resultado do Tratamento , Ativação Viral/efeitos dos fármacos , Adulto Jovem
20.
Sci Rep ; 7(1): 10170, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860577

RESUMO

Latent infection with Toxoplasma gondii has repeatedly been shown to be associated with behavioral changes that are commonly attributed to a presumed increase in dopaminergic signaling. Yet, virtually nothing is known about its effects on dopamine-driven reward processing. We therefore assessed behavior and event-related potentials in individuals with vs. without latent toxoplasmosis performing a rewarded control task. The data show that otherwise healthy young adults with latent toxoplasmosis show a greatly diminished response to monetary rewards as compared to their non-infected counterparts. While this selective effect eliminated a toxoplasmosis-induced speed advantage previously observed for non-rewarded behavior, Toxo-positive subjects could still be demonstrated to be superior to Toxo-negative subjects with respect to response accuracy. Event-related potential (ERP) and source localization analyses revealed that this advantage during rewarded behavior was based on increased allocation of processing resources reflected by larger visual late positive component (LPC) amplitudes and associated activity changes in the right temporo-parietal junction (BA40) and left auditory cortex (BA41). Taken together, individuals with latent toxoplasmosis show superior behavioral performance in challenging cognitive control situations but may at the same time have a reduced sensitivity towards motivational effects of rewards, which might be explained by the presumed increase in dopamine.


Assuntos
Anticorpos Antiprotozoários/metabolismo , Cognição/fisiologia , Recompensa , Toxoplasma/imunologia , Toxoplasmose/psicologia , Adulto , Córtex Auditivo , Estudos de Casos e Controles , Dopamina/metabolismo , Potenciais Evocados , Feminino , Humanos , Masculino , Toxoplasmose/metabolismo , Adulto Jovem
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