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1.
Living Rev Relativ ; 26(1): 4, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533554

RESUMO

We review recent developments in Jackiw-Teitelboim gravity. This is a simple solvable model of quantum gravity in two dimensions (that arises e.g. from the s-wave sector of higher dimensional gravity systems with spherical symmetry). Due to its solvability, it has proven to be a fruitful toy model to analyze important questions such as the relation between black holes and chaos, the role of wormholes in black hole physics and holography, and the way in which information that falls into a black hole can be recovered.

3.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35162953

RESUMO

After solid-organ transplantation, reactivation of the cytomegalovirus (CMV) is often observed in seronegative patients and associated with a high risk of disease and mortality. CMV-specific T cells can prevent CMV reactivation. In a phase 1 trial, CMV-seronegative patients with end-stage renal disease listed for kidney transplantation were subjected to CMV phosphoprotein 65 (CMVpp65) peptide vaccination and further investigated for T-cell responses. To this end, CMV-specific CD8+ T cells were characterized by bulk T-cell-receptor (TCR) repertoire sequencing and combined single-cell RNA and TCR sequencing. In patients mounting an immune response to the vaccine, a common SYE(N)E TCR motif known to bind CMVpp65 was detected. CMV-peptide-vaccination-responder patients had TCR features distinct from those of non-responders. In a non-responder patient, a monoclonal inflammatory T-cell response was detected upon CMV reactivation. The identification of vaccine-induced CMV-reactive TCRs motifs might facilitate the development of cellular therapies for patients wait-listed for kidney transplantation.


Assuntos
Infecções por Citomegalovirus/prevenção & controle , Falência Renal Crônica/terapia , Receptores de Antígenos de Linfócitos T/genética , Proteínas da Matriz Viral/administração & dosagem , Linfócitos T CD8-Positivos/imunologia , Ensaios Clínicos Fase I como Assunto , Citomegalovirus/imunologia , Infecções por Citomegalovirus/imunologia , Vacinas contra Citomegalovirus/administração & dosagem , Vacinas contra Citomegalovirus/imunologia , Humanos , Falência Renal Crônica/imunologia , Transplante de Rim , Análise de Sequência de RNA , Imagem Individual de Molécula , Proteínas da Matriz Viral/imunologia
4.
J Immunol ; 207(10): 2534-2544, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34625521

RESUMO

Human CMV (HCMV) is a ubiquitous pathogen that indelibly shapes the NK cell repertoire. Using transcriptomic, epigenomic, and proteomic approaches to evaluate peripheral blood NK cells from healthy human volunteers, we find that prior HCMV infection promotes NK cells with a T cell-like gene profile, including the canonical markers CD3ε, CD5, and CD8ß, as well as the T cell lineage-commitment transcription factor Bcl11b. Although Bcl11b expression is upregulated during NK maturation from CD56bright to CD56dim, we find a Bcl11b-mediated signature at the protein level for FcεRIγ, PLZF, IL-2Rß, CD3γ, CD3δ, and CD3ε in later-stage, HCMV-induced NK cells. BCL11B is targeted by Notch signaling in T cell development, and culture of NK cells with Notch ligand increases cytoplasmic CD3ε expression. The Bcl11b-mediated gain of CD3ε, physically associated with CD16 signaling molecules Lck and CD247 in NK cells is correlated with increased Ab-dependent effector function, including against HCMV-infected cells, identifying a potential mechanism for their prevalence in HCMV-infected individuals and their prospective clinical use in Ab-based therapies.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Infecções por Citomegalovirus/imunologia , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos/imunologia , Proteínas Repressoras/imunologia , Proteínas Supressoras de Tumor/imunologia , Animais , Complexo CD3/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Transcriptoma
5.
Dtsch Arztebl Int ; 118(15): 262-268, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34114547

RESUMO

BACKGROUND: Vaccination during pregnancy can protect both the expecting mother and the unborn and newborn child from infectious diseases. METHODS: This review is based on publications retrieved by a selective literature search on the immunological particularities of infectious diseases affecting pregnant women, unborn children, and neonates, with particular attention to the guidelines of the German Standing Committee on Vaccinations (Ständige Impfkommission, STIKO) and the pertinent guidelines. RESULTS: Vaccination during pregnancy protects the expecting mother from a severe course of a number of different infectious diseases. Vaccination with inactivated vaccines against influenza, tetanus, and pertussis is effective, safe, and well tolerated. Women who are pregnant or of child-bearing age should be immunized against tetanus according to the STIKO recommendations. All pregnant women from the second trimester onward should receive an inactivated quadrivalent influenza vaccine. The immunity acquired after vaccination with an acellular pertussis vaccine is present only for a limited time. In a cohort study involving 72,781 pregnant women, pertussis vaccination during pregnancy was found to yield 91% protection against pertussis for their subsequently born children in the first three months of life. Further types of vaccine can also be given during pregnancy if indicated. Additional reasonable measures to protect the health of mother and child include the vaccination of other persons in close contact as well as the closure of relevant vaccination gaps among young adults, particularly women of child-bearing age. Treating physicians play a crucial role in encouraging vaccine acceptance by their patients. CONCLUSION: Maternal immunization is a safe and effective strategy for giving neo - nates passive immune protection against life-threatening infections by the vertical transmission of maternal antibodies until they are able to build up their own adaptive immunity.


Assuntos
Vacinas contra Influenza , Influenza Humana , Coqueluche , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Vacinação , Adulto Jovem
6.
Vaccine ; 38(50): 8024-8031, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33160754

RESUMO

BACKGROUND AND AIMS: Children with inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH) receiving immunosuppressive treatment are at risk for severe varicella zoster virus (VZV)-induced disease. This study evaluated vaccination of susceptible patients with stable disease and documented immunoreactivity without interruption of their current immunosuppression (IS). METHODS: This prospective multicentre observational study used a prevaccination checklist to select patients with low-intensity and high-intensity IS for VZV vaccination. Tolerability and safety after immunization were assessed by questionnaire. The immune response was measured by the VZV-IgG concentration, relative avidity index (RAI), and specific lymphocyte proliferative response. RESULTS: A total of 29 VZV vaccinations were performed in 17 seronegative patients aged 3-16 years (IBD n = 15, AIH n = 2). Eight patients received high-intensity immunosuppression, another six low-intensity immunosuppression, and three patients interrupted IS before VZV vaccination. All 29 vaccinations were well tolerated; only minor side effects such as fever and abdominal pain, were reported in two patients. One patient experienced a flare of Crohn's disease the day after vaccination. The VZV-IgG-concentration increased significantly (p = 0.018) after vaccination, and a specific lymphocyte response towards VZV in vitro was detected in all tested patients which correlated with the RAI (r = 0.489; p = 0.078). CONCLUSIONS: VZV vaccination was well tolerated, safe and immunogenic in children receiving ongoing IS due to IBD and AIH. Ensuring immunoreactivity by clinical and laboratory parameters, rather than the type and dosage of IS, is a reasonable approach to decide on live-attenuated virus vaccinations in immunosuppressed children (German clinical trials DRKS00016357).


Assuntos
Varicela , Hepatite Autoimune , Herpes Zoster , Doenças Inflamatórias Intestinais , Adolescente , Anticorpos Antivirais , Criança , Pré-Escolar , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Estudos Prospectivos , Vacinação
7.
Vaccine ; 38(7): 1810-1817, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31879123

RESUMO

BACKGROUND AND AIMS: Immunosuppressed patients are at risk of severe infections with vaccination preventable diseases. We evaluated vaccination rate and immunity of children and adolescents with inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH). METHODS: Immunization rate of 329 children with IBD (n = 300) and AIH (n = 29) was assessed in seven German centres using vaccination certificates, history of chicken pox and by determining anti-varicella zoster virus (VZV) and anti-measles IgG antibodies. RESULTS: Of the total cohort 86% received long-term immunosuppression. Four doses of a hexavalent vaccine were documented in 89%, at least one dose of measles, mumps, and rubella (MMR) vaccination was documented in 325 (99%), with 300 (92%) receiving two doses. Anti-measles IgG concentrations were insufficient in 11% of the immunized patients. VZV vaccination was officially recommended in Germany since 2004, and implemented in 88% born from 2005 onwards. In patients born earlier VZV catch up vaccination only reached 25% (n = 67). Of 118 patients with documented VZV vaccination 25 (21%) did not display sufficient anti-VZV IgG. Of 198 patients with a history of chicken pox, six had undetectable anti-VZV IgG. Of 29 patients having neither had chicken pox nor VZV vaccination, 20 were found to have sufficient anti-VZV IgG. CONCLUSIONS: In our cohort vaccination coverage for hexavalent and MMR vaccinations was good, but insufficient for VZV vaccination in patients born before 2005. Neither the vaccination certificate nor the history of chicken pox is reliable to predict VZV immunity indicating a need for serologic investigations and if needed vaccination before initiating immunosuppressive therapy.


Assuntos
Anticorpos Antivirais/sangue , Hepatite Autoimune/imunologia , Doenças Inflamatórias Intestinais/imunologia , Vacinação/estatística & dados numéricos , Adolescente , Vacina contra Varicela/administração & dosagem , Criança , Alemanha , Humanos , Imunoglobulina G/sangue , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem
8.
Microorganisms ; 7(11)2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31717670

RESUMO

The recombination-activating genes (RAGs) and the DNA cross-link repair 1C gene (DCLRE1C) encode the enzymes RAG1, RAG2 and Artemis. They are critical components of the V(D)J recombination machinery. V(D)J recombination is well known as a prerequisite for the development and antigen diversity of T and B cells. New findings suggested that RAG deficiency impacts the cellular fitness and function of murine NK cells. It is not known whether NK cells from severe combined immunodeficiency (SCID) patients with defective RAGs or DCLRE1C (RAGs-/DCLRE1C--NK) are active against virus infections. Here, we evaluated the anti-HCMV activity of RAGs-/DCLRE1C--NK cells. NK cells from six SCID patients were functional in inhibiting HCMV transmission between cells in vitro. We also investigated the expansion of HCMV-induced NK cell subset in the RAG- or DCLRE1C-deficient patients. A dynamic expansion of NKG2C+ NK cells in one RAG-2-deficient patient was observed post HCMV acute infection. Our study firstly reveals the antiviral activity of human RAGs-/ DCLRE1C--NK cells.

9.
Dtsch Med Wochenschr ; 144(4): 239-243, 2019 02.
Artigo em Alemão | MEDLINE | ID: mdl-30759472

RESUMO

The epidemiological effect of vaccination is that it primarily reduces the incidence and prevalence of infectious agents and diseases, providing ideal conditions (also from an economic point of view) for prevention. Goal of vaccination is first the individual protection. Other goals may be "herd immunity", regional repression and global extinction. The STIKO provides recommendations for the implementation of vaccinations and for the implementation of other measures for the specific prevention of communicable diseases and develops criteria for the differentiation of a customary vaccination reaction and damage to health beyond the usual extent of a vaccination reaction. Earlier vaccination recommendations based on "expert opinion" but today are based on the best available evidence. Current STIKO recommendations include vaccination against seasonal influenza, vaccination against HPV, Tdap booster, tetanus PEP, and vaccine management in practice and among migrants. For the success of the vaccination recommendations, it is first and foremost crucial that the medical profession complies with the obligation to inform about vaccination options and needs vis-à-vis patients or guardians.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Vacinação , Alemanha/epidemiologia , Humanos , Vacinação/legislação & jurisprudência , Vacinação/normas , Vacinação/estatística & dados numéricos
10.
Front Immunol ; 9: 1129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887865

RESUMO

Human cytomegalovirus (HCMV) persistently infects 40-90% of the human population but in the face of a normal immune system, viral spread and dissemination are efficiently controlled thus preventing clinically signs and disease. HCMV-infected hosts produce a remarkably large amount of HCMV-specific CD4+ and CD8+ T cells that can even reach 20-50% of total T memory cells in the elderly. How HCMV may elicit such large and long-lasting T-cell responses in the absence of detectable viremia has not been elucidated yet. Additionally, HCMV is known to encode several gene products that potently inhibit T-cell recognition of infected cells. The best characterized are the four immune evasive US2, US3, US6, and US11 genes that by different mechanisms account for major histocompatibility complex (MHC) class I and class II degradation and intracellular retention in infected cells. By infecting M1 and M2 human macrophages (Mφ) with the wild-type HCMV strain TB40E or a mutant virus deleted of the four immune evasive genes US2, US3, US6, and US11, we demonstrated that human Mφ counteract the inhibitory potential of the US2-11 genes and remain capable to present peptides via MHC class I and class II molecules. Moreover, by sorting the infected and bystander cells, we provide evidence that both infected and bystander Mφ contribute to antigen presentation to CD4+ and CD8+ T cells. The T cells responding to TB40E-infected Mφ show markers of the T effector memory compartment, produce interferon-γ, and express the lytic granule marker CD107a on the cell surface, thus mirroring the HCMV-specific T cells present in healthy seropositive individuals. All together, our findings reveal that human Mφ escape inhibition of MHC-dependent antigen presentation by HCMV and continue to support T cell proliferation and activation after HCMV infection. Taking into account that Mφ are natural targets of HCMV infection and a site of viral reactivation from latency, our findings support the hypothesis that Mφ play crucial roles for the lifelong maintenance and expansion of HCMV-committed T cells in the human host.


Assuntos
Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Macrófagos/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Antígenos Virais/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular , Citomegalovirus/genética , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/virologia , Regulação Viral da Expressão Gênica , Humanos , Memória Imunológica , Ativação Linfocitária/imunologia , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas Virais/genética , Proteínas Virais/imunologia
11.
Rev Med Virol ; 28(3): e1975, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29626377

RESUMO

As early as 1943, the German physician Helmut Ruska visualized the virus of varicella and zoster (at that time, he was not completely certain whether the virus was the same) by the newly developed electron microscope; he is regarded as the discoverer of this virus. Here, we present a translation of his classical paper into the English language. In our introduction and commentary to his paper, we discuss the significance of Helmut Ruska's work for the development of virology, his distinction between the varicella, zoster, and herpes virus group on one hand and poxviruses on the other, as well as the development of imaging techniques which have refined or substituted for electron microscopy of viruses and virus-infected cells.


Assuntos
Varicela/virologia , Herpes Zoster/virologia , Herpesvirus Humano 3/classificação , Herpesvirus Humano 3/ultraestrutura , Humanos
12.
Pediatr Rheumatol Online J ; 16(1): 15, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499726

RESUMO

BACKGROUND: The goal of this study was to apply the varicella zoster virus (VZV) vaccine to patients with pediatric rheumatic diseases (PRD) at risk for severe chickenpox, without interrupting their current immunosuppression, including biological agents, using an immunological-based pre-vaccination checklist to assure safety. A pre-vaccination checklist was implemented to ensure adequate immune competence prior to immunization. METHODS: This prospective study included seronegative patients (VZV-IgG ≤200 mIU/ml) and patients who had previously received only a single dose of VZV vaccine. All vaccinees demonstrated clinically inactive PRD. Patients were categorized according to their actual treatment in low-intensity IS (LIIS) and high-intensity IS (HIIS) including biological therapy. The pre-vaccination checklist defined thresholds for the following basic laboratory tests: white blood cell count ≥3000/mm3, lymphocytes ≥1200/mm3, serum IgG ≥500 mg/dl, IgM ≥20 mg/dl, tetanus toxoid antibody ≥0.1 IU/ml. In case of HIIS additional specifications included a CD4+ lymphocyte count ≥200/mm3 and a positive T-cell function (via analyzable positive control of a standard tuberculosis interferon-gamma-release-assay (TB-IGRA) indicating mitogen-induced T cell proliferation). Patients who met the criteria of the pre-vaccination checklist received the first and/or second VZV vaccination. Immunologic response and side effects were monitored. RESULTS: Twenty-three patients were recruited of whom nine had already received one VZV immunization before initiating IS. All patients met the pre-vaccination checklist criteria despite ongoing IS. There was no overall difference in VZV-IgG levels when comparing the LIIS (n=9) and HIIS (n=14) groups. In total, 21 patients (91%) showed a positive vaccination response, after the first immunization the median VZV-IgG across all patients was 224 (59-1219) mIU/ml (median (range)), after booster immunization it increased to 882 (30-4685) mIU/ml. Two patients in the HIIS group failed to raise positive VZV-IgG, despite booster immunization. All nine patients receiving only the second immunization on IS reached high titers of VZV-IgG >500 mIU/ml (1117 (513-4685) mIU/ml). There were no cases of rash or other vaccine-induced varicella disease symptoms and no evidence of PRD flare. CONCLUSIONS: VZV vaccination is safe and largely immunogenic in children with ongoing IS fulfilling an immunological based pre-vaccination checklist. This new approach is based on immunologic function rather than on type of medications. TRIAL REGISTRATION NUMBER: ISRCRTN trial registration number 21654693 , date of registration February 12, 2018, retrospectively registered.


Assuntos
Lista de Checagem/métodos , Vacina contra Varicela/administração & dosagem , Varicela/imunologia , Herpesvirus Humano 3/imunologia , Doenças Reumáticas/imunologia , Adolescente , Fatores Biológicos/administração & dosagem , Fatores Biológicos/efeitos adversos , Vacina contra Varicela/efeitos adversos , Criança , Pré-Escolar , Feminino , Alemanha , Humanos , Hospedeiro Imunocomprometido/imunologia , Imunoglobulina G/sangue , Masculino , Estudos Prospectivos , Vacinação/efeitos adversos , Vacinação/métodos
13.
J Gen Virol ; 98(12): 3068-3085, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29165229

RESUMO

Apart from classical antigen-presenting cells (APCs) like dendritic cells and macrophages, there are semiprofessional APCs such as endothelial cells (ECs) and Langerhans' cells. Human cytomegalovirus (HCMV) infects a wide range of cell types including the ECs which are involved in the trafficking and homing of T cells. By investigating the interaction of naïve T cells obtained from HCMV-seronegative umbilical cord blood with autologous HCMV-infected human umbilical vein ECs (HUVECs), we could show that the activation of naïve T cells occurred after 1 day of peripheral blood mononuclear cell (PBMC) exposure to HCMV-infected HUVECs. The percentage of activated T cells increased over time and the activation of naïve T cells was not induced by either autologous uninfected HUVECs or by autologous HCMV-infected fibroblasts. The activation of T cells occurred also when purified T cells were co-cultured with HCMV-infected HUVECs. In addition, in most of the donors only CD8+ T cells were activated, when the purified T cells were exposed to HCMV-infected HUVECs. The activation of naïve T cells was inhibited when the NKG2D receptor was blocked on the surface of T cells and among the different NKG2D ligands, we identified two ligands (ULBP4 and MICA) on HCMV-infected HUVECs which might be the interaction partners of the NKG2D receptor. Using a functional cell culture assay, we could show that these activated naïve T cells specifically inhibited HCMV transmission. Altogether, we identified a novel specific activation mechanism of naïve T cells from the umbilical cord by HCMV-infected autologous HUVECs through interaction with NKG2D.

14.
J Virol ; 91(22)2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28878085

RESUMO

Human cytomegalovirus (HCMV) persistently infects 40% to 100% of the human population worldwide. Experimental and clinical evidence indicates that humoral immunity to HCMV plays an important role in restricting virus dissemination and protecting the infected host from disease. Specific immunoglobulin preparations from pooled plasma of adults selected for high titers of HCMV antibodies have been used for the prevention of CMV disease in transplant recipients and pregnant women. Even though incubation of HCMV particles with these preparations leads to the neutralization of viral infectivity, it is still unclear whether the antibody-treated HCMV particles (referred to here as HCMV-Ab) enter the cells and modulate antiviral immune responses. Here we demonstrate that HCMV-Ab did enter macrophages. HCMV-Ab did not initiate the expression of immediate early antigens (IEAs) in macrophages, but they induced an antiviral state and rendered the cells less susceptible to HCMV infection upon challenge. Resistance to HCMV infection seemed to be due to the activation of intrinsic restriction factors and was independent of interferons. In contrast to actively infected cells, autologous NK cells did not degranulate against HCMV-Ab-treated macrophages, suggesting that these cells may not be eliminated by innate effector cells. Interestingly, HCMV-Ab-treated macrophages stimulated the proliferation of autologous adaptive CD4+ and CD8+ T cells. Our findings not only expand the current knowledge on virus-antibody immunity but may also be relevant for future vaccination strategies.IMPORTANCE Human cytomegalovirus (HCMV), a common herpesvirus, establishes benign but persistent infections in immunocompetent hosts. However, in subjects with an immature or dysfunctional immune system, HCMV is a major cause of morbidity and mortality. Passive immunization has been used in different clinical settings with variable clinical results. Intravenous hyperimmune globulin preparations (IVIg) are obtained from pooled adult human plasma selected for high anti-CMV antibody titers. While HCMV neutralization can be shown in vitro using different systems, data are lacking regarding the cross-influence of IVIg administration on the cellular immune responses. The aim of this study was to evaluate the effects of IVIg on distinct components of the immune response against HCMV, including antigen presentation by macrophages, degranulation of innate natural killer cells, and proliferation of adaptive CD4+ and CD8+ T cells.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Imunidade Celular , Macrófagos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Infecções por Citomegalovirus/patologia , Feminino , Humanos , Imunidade Inata , Macrófagos/patologia , Macrófagos/virologia , Masculino
16.
Theranostics ; 7(6): 1705-1718, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28529646

RESUMO

Rationale: Patients receiving an allogeneic stem cell graft from cytomegalovirus (CMV) seronegative donors are particularly prone to CMV reactivation with a high risk of disease and mortality. Therefore we developed and manufactured a novel vaccine and initiated a clinical phase I trial with a CMV phosphoprotein 65 (CMVpp65)-derived peptide. Methods: Ten patients after allogeneic stem cell transplantation received four vaccinations at a biweekly interval. All patients were monitored for CMVpp65 antigenemia. Flow cytometry for CMV-specific CD8+ and γδ T cells as well as neutralizing anti-CMV antibodies were correlated to clinical parameters. Results: The vaccination was well tolerated. Seven of nine patients cleared CMVpp65 antigenemia after four vaccinations and are still free from antigenemia to this day. Two patients with CMV reactivation showed persisting CMV antigenemia. One patient received prophylactic vaccination and did not develop antigenemia. An increase of up to six-fold in frequency of both CMV-specific CD8+ T cells and/or Vδ2negative γδ T cells was detected. Titers of neutralizing antibodies increased up to the tenfold. Humoral and cellular immune responses correlated with clearance of CMV. Conclusion: In summary, CMVpp65 peptide vaccination for patients after allogeneic stem cell transplantation at high risk for CMV reactivation was safe, well tolerated and clinically encouraging. A study in solid-organ transplant patients is ongoing.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas , Fosfoproteínas/imunologia , Proteínas da Matriz Viral/imunologia , Anticorpos Antivirais/sangue , Vacinas contra Citomegalovirus/administração & dosagem , Vacinas contra Citomegalovirus/efeitos adversos , Humanos , Fosfoproteínas/administração & dosagem , Fosfoproteínas/efeitos adversos , Resultado do Tratamento , Proteínas da Matriz Viral/administração & dosagem , Proteínas da Matriz Viral/efeitos adversos
17.
Med Microbiol Immunol ; 206(2): 175-185, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28176006

RESUMO

Zika virus (ZIKV) is an emerging pathogen that causes congenital infections which may result in birth defects, such as microcephaly. Currently, no approved treatment or vaccination is available. ZIKV can be readily detected in cell culture where virally infected cells are normally stained by specific antibodies. As ZIKV regularly causes a cytopathic effect, we were wondering whether this viral property can be used to quantitatively determine viral infectivity. We here describe the use of an 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium bromide-(MTT)-based cell viability assay that allows to determine ZIKV-induced cell death. We show that this colorimetric assay quantifies ZIKV infection over a broad range of viral dilutions in both monkey and human cells. It allows to determine inhibitory activities of antivirals that block ZIKV or to define the neutralizing antibody titers of ZIKV antisera. This MTT-based ZIKV detection assay can be evaluated by naked eye or computational tools, has a broad linear range, does not require large equipment or costly reagents, and thus represents a promising alternative to antibody-based assays, in particular in resource-poor settings. We propose to use this simple, fast, and cheap method for quantification of ZIKV neutralizing antibodies and testing of antiviral compounds.


Assuntos
Colorimetria/métodos , Ensaios de Triagem em Larga Escala/métodos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologia , Zika virus , Animais , Anticorpos Neutralizantes/imunologia , Linhagem Celular , Sobrevivência Celular , Chlorocebus aethiops , Humanos , Soros Imunes/imunologia , Interferon-alfa/farmacologia , Testes de Neutralização/métodos , Células Vero , Zika virus/efeitos dos fármacos , Zika virus/imunologia , Infecção por Zika virus/imunologia
19.
J Gen Virol ; 97(9): 2376-2386, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27405754

RESUMO

We established a new 'transmission kinetic assay (TKA)' to quantify the human cytomegalovirus (HCMV) transmission between cells in vitro and to phenotypically characterize HCMV strains based on their mode of transmission by flow cytometric analysis. On one hand we used the genetically modified HCMV strain TB40/E-delUL16-GFP, and on the other hand, clinical isolates. When twofold diluted infecting cells were seeded to a constant number of uninfected cells, the transmission of virus on each day (day 0-5) followed a strictly linear pattern, which was characterized by a linear equation. The slope of this linear equation represents 'the number of newly infected cells per infecting cell'. To standardize the TKA, the slopes of the different days were plotted against the corresponding days. This resulted in a new linear equation with a new slope value, which characterizes the transmission kinetics. To differentiate cell-associated and cell-free modes of transmission, we introduced HCMV neutralizing antibodies into the system. The slope was 0.9 (±0.5) when the virus exhibited only cell-associated transmission and was 4.1 (±0.7) when the virus exhibited both modes of transmission. TKA was then applied to different clinical isolates and they were phenotypically characterized based on their modes of transmission. Apart from the quantitative analysis of HCMV transmission and the phenotypical characterization of clinical isolates, the TKA was applied to quantify the inhibition of clinical isolates transmission by immune cells and to study the effect of cytokine (IL-2) on immune cells inhibiting HCMV transmission.


Assuntos
Citomegalovirus/crescimento & desenvolvimento , Internalização do Vírus , Liberação de Vírus , Citomegalovirus/imunologia , Citomegalovirus/isolamento & purificação , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/virologia , Citometria de Fluxo , Humanos , Imunidade Celular , Interleucina-2/metabolismo , Cultura de Vírus
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