Impact of cytomegalovirus infection on B cell differentiation and cytokine production in multiple sclerosis

Altres ajuts: This work was supported by the EU FP7-MINECO Infect-ERA Program, and Red Española de Esclerosis Múltiple (REEM) from the Instituto de Salud Carlos III, the European Regional Development Fund (Grant RD16/0015/0011), and the Spanish Ministry of Economy and Competitiveness.Human cytomegalovirus (HCMV) infection has been recently associated with a low risk of multiple sclerosis (MS), yet the basis behind this observation remains uncertain. In this study, we aimed to determine in MS patients whether HCMV induces modifications in the peripheral B cell compartment. HCMV serostatus was determined in 73 MS patients (55 relapsing-remitting MS (RRMS); 18 progressive MS (PMS)) and 30 healthy controls, assessing their B cell immunophenotype and cytokine production (GM-CSF, IL-6, IL-10, and TNFα) by flow cytometry. HCMV seropositivity in untreated MS patients (n = 45) was associated with reduced switched memory B cells, contrasting with an opposite effect in PMS. Expansions of transitional B cells were observed in HCMV(+) IFNβ-treated RRMS patients but not in HCMV(−) cases (p < 0.01), suggesting that HCMV may influence the distribution of B cell subsets modulating the effects of IFNβ. Considering the B cell functional profile, HCMV(−) PMS displayed an increased secretion of proinflammatory cytokines (IL-6, TNFα) as compared to HCMV(+) PMS and RRMS cases (p < 0.001). Our study reveals an influence of HCMV infection on the phenotype and function of B cells, promoting early differentiation stages in RRMS and reducing the proinflammatory cytokine profile in advanced MS forms, which might be related with the putative protective role of this virus in MS

Respuesta adaptativa mediada por células natural killer en la esclerosis múltiple

L'esclerosi múltiple (EM) és una malaltia inflamatòria desmielinitzant del sistema nerviós central. En el seu desenvolupament hi intervenen factors genètics i mediambientals, destacant la influència d'infeccions per herpesvirus. El virus Epstein Barr (VEB) s'ha associat a un major risc de desenvolupar la malaltia, malgrat tot, el citomegalovirus (HCMV) podria conferir una menor susceptibilitat al desenvolupament de l'EM. A la immunopatologia de l'EM, intervenen tant els limfòcits T com B així com el sistema immune innat, i dins d'aquest, les cèl·lules "natural killer" (NK). EL HCMV és un dels factors que més influeixen a l'hora de modificar el sistema immune, incrementant la població de cèl·lules T de memòria específiques pel virus i produint una expansió en alguns subjectes de cèl·lules NK adaptatives, que expressen el receptor activador NKG2C(+) que s'ha associat a un menor risc de progressió de la malaltia. S'han descrit altres canvis adaptatius associats a la infecció crònica pel HCMV, com el silenciament epigenètic del factor de transcripció PLZF ("promyelocytic leukemia zinc finger ") i la pèrdua de la cadena gamma en el complex de senyalització del receptor Fc CD16 (FcRγ) que s'ha associat a una major activitat NK mitjançan citotoxicitat cel·lular depenent d'anticòs (ADCC: "Antibody Dependent Cell-mediated Cytotoxicity"). L'objectiu del present treball fou avaluar els canvis induïts pel HCMV en el compartiment NK, tant en el seu immunofenotip com en la seva funció, estudiant les implicacions de la resposta adaptativa NK en la clínica dels pacients amb EM, tenint en compte la seroprevalença del HCMV, així com el seu possible impacte sobre el control d'altres infeccions virals que podrien estar implicades en la malaltia, com la del VEB. En el nostre estudi, observem una menor seroprevalença del HCMV en fases inicials de la malaltia, així com una correlació negativa en subjectes HCMV(+) entre el temps d'evolució de la malaltia i la resposta humoral determinada pels títols d'anti-EBNA-1, això podria indicar un major control de la infecció per VEB en aquells casos amb infecció crònica per HCMV. Així mateix, els individus HCMV(+), mostraren una major proporció de cèl·lules T diferenciades terminals, implicant que la presència de cèl·lules T menys diferenciades en pacients HCMV(-) podria donar lloc a una major susceptibilitat a desenvolupar processos inflamatoris. Posteriorment, es va analitzar la influència del HCMV en el compartiment NK, trobant que la infecció per HCMV s'associava a un immunofenotip adaptatiu tant en controls sans com en pacients amb EM, però amb diferències en la distribució en pacients, influenciades per la forma clínica de la malaltia i el tractament amb interferó-beta. Així mateix, l'expressió de NKG2C(+) associada a la infecció crònica per HCMV es va associar a una menor discapacitat ja des de fases inicials de la malaltia, donant suport a la hipòtesi del HCVM com a possible factor protector. Addicionalment s'observa una major pèrdua de PLZF en pacients amb EM HCMV(-) respecte als controls, suggerint que altres factors independents al HCMV podrien induir el desenvolupament de marcadors adaptatius en les cèl·lules NK en el context de l'EM. Finalment, el nostre estudi va avaluar la influència de l'immunofenotip NK en la funció d'aquests limfòcits en pacients amb EM, trobant que l'ADCC de les cèl·lules NK contra limfòcits B infectats per VEB pot diferir en l'EM en relació amb la seva forma clínica, sent menor en pacients amb formes primàries progressives, i que al contrari que en subjectes sans, un immunofenotip adaptatiu en l'EM no s'associa a una major ADCC, donant suport a la hipòtesi d'una menor resposta NK adaptativa en pacients amb EM.La esclerosis múltiple (EM) es una enfermedad inflamatoria desmielinizante del sistema nervioso central. En su desarrollo intervienen factores genéticos y medioambientales, destacando la influencia de infecciones por herpesvirus. El Virus de Epstein Barr (VEB) se ha asociado con un mayor riesgo de desarrollo de la enfermedad, sin embargo, el citomegalovirus (HCMV) podría conferir una menor susceptibilidad al desarrollo de la EM. En la inmunopatología de la EM intervienen tanto linfocitos T como B, como el sistema inmune innato, y dentro de este, las células "natural killer" (NK). El HCMV es uno de los factores más influyentes a la hora de modificar el sistema inmune, incrementando la población de células T de memoria específicas para el virus y produciendo una expansión en algunos sujetos de células NK adaptativas, que expresan el receptor activador NKG2C(+) que ha sido asociado con un menor riesgo de progresión de la enfermedad. Se han descrito otros cambios adaptativos asociados a la infección crónica por el HCMV, como la silenciación epigenética del factor de transcripción PLZF ("promyelocytic leukemia zinc finger ") y la pérdida de la cadena gamma en el complejo de señalización del receptor Fc CD16 (FcRγ) que se ha asociado con una mayor actividad NK mediante citotoxicidad celular dependiente de anticuerpos (ADCC: "Antibody Dependent Cell-mediated Cytotoxicity"). El objetivo del presente trabajo fue evaluar los cambios inducidos por el HCMV en el compartimento NK, tanto en su inmunofenotipo como en su función, estudiando las implicaciones de la repuesta adaptativa NK en la clínica de los pacientes con EM, teniendo en cuenta la seroprevalencia del HCMV, así como su posible impacto sobre el control de otras infecciones virales que podrían estar implicadas en la enfermedad, tal como la del VEB. En nuestro estudio, observamos una menor seroprevalencia del HCMV en fases iniciales de la enfermedad, así como una correlación negativa, en sujetos HCMV(+), entre el tiempo de evolución de la enfermedad y la respuesta humoral determinada por los títulos de anti-EBNA-1, lo que podría indicar un mayor control de la infección por VEB en aquellos casos con infección crónica por HCMV. Adicionalmente, los individuos HCMV(+), mostraron una mayor proporción de células T diferenciadas terminales, implicando que la presencia de células T menos diferenciadas en pacientes HCMV(-) podría conferir mayor susceptibilidad a desarrollar procesos inflamatorios. Posteriormente, se analizó la influencia del HCMV en el compartimento NK, encontrando que la infección por HCMV se asoció a un inmunofenotipo adaptativo tanto en controles sanos como en pacientes con EM, pero con diferencias en la distribución de marcadores adaptativos en pacientes, influenciadas por la forma clínica de la enfermedad y el tratamiento con interferón-beta. Asimismo, la expresión de NKG2C(+) asociado a la infección crónica por HCMV se asoció a una menor discapacidad ya desde fases iniciales de la enfermedad, apoyando la hipótesis del HCMV como posible factor protector. Adicionalmente, se observó una mayor pérdida de PLZF en pacientes con EM HCMV(-) con respecto a los controles, sugiriendo que otros factores independientes al HCMV podrían inducir el desarrollo de marcadores adaptativos en las células NK en el contexto de la EM. Por último, nuestro estudio evaluó la influencia del inmunofenotipo NK en la función de estos linfocitos en pacientes con EM, encontrando que la ADCC de las células NK contra linfocitos B infectados por VEB puede diferir en la EM en relación a su forma clínica, siendo menor en pacientes con formas primarias progresivas, y que, al contrario que en sujetos sanos, un inmunofenotipo adaptativo en la EM, no se asocia a una mayor ADCC, apoyando la hipótesis de una menor respuesta NK adaptativa en pacientes con EM.Multiple Sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Both genetic and environmental factors are involved in the development of MS, with a remarkable influence of herpesvirus infections. Epstein-Barr Virus (EBV) is associated with an increased risk of MS. By contrast, human cytomegalovirus was recently related to lower MS susceptibility. T cells and, recently B lymphocytes, are involved in MS immunopathogenesis. In addition, the innate immune system, and in particular, natural killer (NK) cells, have also been implicated in the disease. In this regard, HCMV exerts a profound impact on the immune system, increasing HCMV specific memory T cells, and promoting a persistent reconfiguration of the NK cell compartment characterized by an expansion of NKG2C(+) NK cells, which have been associated with lower disability risk in MS patients. Additional associated-adaptive NK cell markers include the epigenetic silencing of the promyelocytic leukemia zinc finger (PLZF) transcription factor, and the loss of the gamma chain adaptor coupled to CD16 (FcRγ), which has been related to higher antibody dependent cell-mediated cytotoxicity (ADCC) by NK cells. The aim of the present work was to evaluate HCMV-induced changes on the NK cell compartment in MS. We evaluated the NK cell adaptive immunophenotype as well as the function of these lymphocytes, assessing the implications of the adaptive NK cell response in the clinical course of MS patients, as well as the impact of HCMV chronic infection on humoral responses to other herpesvirus infections (i.e., EBV) involved in the disease. We observed a low HCMV seroprevalence in early MS patients that was independent of age. Moreover, HCMV(+) early MS patients had an inverse correlation between MS duration and the humoral response to EBV determined by anti-EBNA-1 IgG index, which might suggest a higher immune control of EBV infection in HCMV(+) cases by mechanisms of heterologous immunity between both viruses. In addition, HCMV(+) MS patients had a higher proportion of differentiated terminal T cells as compared to HCMV(-) cases independently of other clinical characteristics, suggesting that the differentiation of the T cell compartment might be involved in the putative protective role of HCMV in MS. Evaluating the HCMV influence on the NK cell compartment, we found that chronic HCMV infection was associated to an adaptive NK cell immunophenotype, that was characterized by higher expression of NKG2C, and lower of FcRγ and PLZF in NK cells, both in healthy controls and MS patients. However, adaptive NK cell markers in patients were influenced by MS clinical form and treatment with interferon beta. Moreover, a higher NKG2C(+) expression in NK cells was related to lower MS disability in early MS patients, supporting the hypothesis that HCMV may reduce MS risk. Additionally, we observed a higher PLZF loss in HCMV(-) MS patients as compared to controls, suggesting that other factors independent to HCMV infection could induce the expression of the adaptive NK cell markers in the context of MS. Finally, we evaluated the influence of the adaptive NK cell immunophenotype on the function of these lymphocytes in MS. We found that antibody dependent cell-mediated cytotoxicity (ADCC) responses by NK cells against EBV(+) lymphoblastoid cell lines may differ in relation to MS clinical form, perceiving a lower ADCC function in primary progressive MS patients. Furthermore, in contrast to healthy controls, an adaptive immunophenotype was not associated to higher ADCC in MS. Overall, our results provides further insights on the putative protective role of HCMV in MS, suggesting that an adaptive NK cell response induced by chronic HCMV infection may be deficient in MS patients

Respuesta adaptativa mediada por células natural killer en la esclerosis múltiple

L’esclerosi múltiple (EM) és una malaltia inflamatòria desmielinitzant del sistema nerviós central. En el seu desenvolupament hi intervenen factors genètics i mediambientals, destacant la influència d’infeccions per herpesvirus. El virus Epstein Barr (VEB) s’ha associat a un major risc de desenvolupar la malaltia, malgrat tot, el citomegalovirus (HCMV) podria conferir una menor susceptibilitat al desenvolupament de l’EM. A la immunopatologia de l’EM, intervenen tant els limfòcits T com B així com el sistema immune innat, i dins d’aquest, les cèl·lules “natural killer” (NK). EL HCMV és un dels factors que més influeixen a l’hora de modificar el sistema immune, incrementant la població de cèl·lules T de memòria específiques pel virus i produint una expansió en alguns subjectes de cèl·lules NK adaptatives, que expressen el receptor activador NKG2C(+) que s’ha associat a un menor risc de progressió de la malaltia. S’han descrit altres canvis adaptatius associats a la infecció crònica pel HCMV, com el silenciament epigenètic del factor de transcripció PLZF (“promyelocytic leukemia zinc finger ”) i la pèrdua de la cadena gamma en el complex de senyalització del receptor Fc CD16 (FcRγ) que s’ha associat a una major activitat NK mitjançan citotoxicitat cel·lular depenent d’anticòs (ADCC: “Antibody Dependent Cell-mediated Cytotoxicity”). L’objectiu del present treball fou avaluar els canvis induïts pel HCMV en el compartiment NK, tant en el seu immunofenotip com en la seva funció, estudiant les implicacions de la resposta adaptativa NK en la clínica dels pacients amb EM, tenint en compte la seroprevalença del HCMV, així com el seu possible impacte sobre el control d’altres infeccions virals que podrien estar implicades en la malaltia, com la del VEB. En el nostre estudi, observem una menor seroprevalença del HCMV en fases inicials de la malaltia, així com una correlació negativa en subjectes HCMV(+) entre el temps d’evolució de la malaltia i la resposta humoral determinada pels títols d’anti-EBNA-1, això podria indicar un major control de la infecció per VEB en aquells casos amb infecció crònica per HCMV. Així mateix, els individus HCMV(+), mostraren una major proporció de cèl·lules T diferenciades terminals, implicant que la presència de cèl·lules T menys diferenciades en pacients HCMV(-) podria donar lloc a una major susceptibilitat a desenvolupar processos inflamatoris. Posteriorment, es va analitzar la influència del HCMV en el compartiment NK, trobant que la infecció per HCMV s’associava a un immunofenotip adaptatiu tant en controls sans com en pacients amb EM, però amb diferències en la distribució en pacients, influenciades per la forma clínica de la malaltia i el tractament amb interferó-beta. Així mateix, l’expressió de NKG2C(+) associada a la infecció crònica per HCMV es va associar a una menor discapacitat ja des de fases inicials de la malaltia, donant suport a la hipòtesi del HCVM com a possible factor protector. Addicionalment s’observa una major pèrdua de PLZF en pacients amb EM HCMV(-) respecte als controls, suggerint que altres factors independents al HCMV podrien induir el desenvolupament de marcadors adaptatius en les cèl·lules NK en el context de l’EM. Finalment, el nostre estudi va avaluar la influència de l’immunofenotip NK en la funció d’aquests limfòcits en pacients amb EM, trobant que l’ADCC de les cèl·lules NK contra limfòcits B infectats per VEB pot diferir en l’EM en relació amb la seva forma clínica, sent menor en pacients amb formes primàries progressives, i que al contrari que en subjectes sans, un immunofenotip adaptatiu en l’EM no s’associa a una major ADCC, donant suport a la hipòtesi d’una menor resposta NK adaptativa en pacients amb EM.La esclerosis múltiple (EM) es una enfermedad inflamatoria desmielinizante del sistema nervioso central. En su desarrollo intervienen factores genéticos y medioambientales, destacando la influencia de infecciones por herpesvirus. El Virus de Epstein Barr (VEB) se ha asociado con un mayor riesgo de desarrollo de la enfermedad, sin embargo, el citomegalovirus (HCMV) podría conferir una menor susceptibilidad al desarrollo de la EM. En la inmunopatología de la EM intervienen tanto linfocitos T como B, como el sistema inmune innato, y dentro de este, las células “natural killer” (NK). El HCMV es uno de los factores más influyentes a la hora de modificar el sistema inmune, incrementando la población de células T de memoria específicas para el virus y produciendo una expansión en algunos sujetos de células NK adaptativas, que expresan el receptor activador NKG2C(+) que ha sido asociado con un menor riesgo de progresión de la enfermedad. Se han descrito otros cambios adaptativos asociados a la infección crónica por el HCMV, como la silenciación epigenética del factor de transcripción PLZF (“promyelocytic leukemia zinc finger “) y la pérdida de la cadena gamma en el complejo de señalización del receptor Fc CD16 (FcRγ) que se ha asociado con una mayor actividad NK mediante citotoxicidad celular dependiente de anticuerpos (ADCC: “Antibody Dependent Cell-mediated Cytotoxicity”). El objetivo del presente trabajo fue evaluar los cambios inducidos por el HCMV en el compartimento NK, tanto en su inmunofenotipo como en su función, estudiando las implicaciones de la repuesta adaptativa NK en la clínica de los pacientes con EM, teniendo en cuenta la seroprevalencia del HCMV, así como su posible impacto sobre el control de otras infecciones virales que podrían estar implicadas en la enfermedad, tal como la del VEB. En nuestro estudio, observamos una menor seroprevalencia del HCMV en fases iniciales de la enfermedad, así como una correlación negativa, en sujetos HCMV(+), entre el tiempo de evolución de la enfermedad y la respuesta humoral determinada por los títulos de anti-EBNA-1, lo que podría indicar un mayor control de la infección por VEB en aquellos casos con infección crónica por HCMV. Adicionalmente, los individuos HCMV(+), mostraron una mayor proporción de células T diferenciadas terminales, implicando que la presencia de células T menos diferenciadas en pacientes HCMV(-) podría conferir mayor susceptibilidad a desarrollar procesos inflamatorios. Posteriormente, se analizó la influencia del HCMV en el compartimento NK, encontrando que la infección por HCMV se asoció a un inmunofenotipo adaptativo tanto en controles sanos como en pacientes con EM, pero con diferencias en la distribución de marcadores adaptativos en pacientes, influenciadas por la forma clínica de la enfermedad y el tratamiento con interferón-beta. Asimismo, la expresión de NKG2C(+) asociado a la infección crónica por HCMV se asoció a una menor discapacidad ya desde fases iniciales de la enfermedad, apoyando la hipótesis del HCMV como posible factor protector. Adicionalmente, se observó una mayor pérdida de PLZF en pacientes con EM HCMV(-) con respecto a los controles, sugiriendo que otros factores independientes al HCMV podrían inducir el desarrollo de marcadores adaptativos en las células NK en el contexto de la EM. Por último, nuestro estudio evaluó la influencia del inmunofenotipo NK en la función de estos linfocitos en pacientes con EM, encontrando que la ADCC de las células NK contra linfocitos B infectados por VEB puede diferir en la EM en relación a su forma clínica, siendo menor en pacientes con formas primarias progresivas, y que, al contrario que en sujetos sanos, un inmunofenotipo adaptativo en la EM, no se asocia a una mayor ADCC, apoyando la hipótesis de una menor respuesta NK adaptativa en pacientes con EM.Multiple Sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Both genetic and environmental factors are involved in the development of MS, with a remarkable influence of herpesvirus infections. Epstein-Barr Virus (EBV) is associated with an increased risk of MS. By contrast, human cytomegalovirus was recently related to lower MS susceptibility. T cells and, recently B lymphocytes, are involved in MS immunopathogenesis. In addition, the innate immune system, and in particular, natural killer (NK) cells, have also been implicated in the disease. In this regard, HCMV exerts a profound impact on the immune system, increasing HCMV specific memory T cells, and promoting a persistent reconfiguration of the NK cell compartment characterized by an expansion of NKG2C(+) NK cells, which have been associated with lower disability risk in MS patients. Additional associated-adaptive NK cell markers include the epigenetic silencing of the promyelocytic leukemia zinc finger (PLZF) transcription factor, and the loss of the gamma chain adaptor coupled to CD16 (FcRγ), which has been related to higher antibody dependent cell-mediated cytotoxicity (ADCC) by NK cells. The aim of the present work was to evaluate HCMV-induced changes on the NK cell compartment in MS. We evaluated the NK cell adaptive immunophenotype as well as the function of these lymphocytes, assessing the implications of the adaptive NK cell response in the clinical course of MS patients, as well as the impact of HCMV chronic infection on humoral responses to other herpesvirus infections (i.e., EBV) involved in the disease. We observed a low HCMV seroprevalence in early MS patients that was independent of age. Moreover, HCMV(+) early MS patients had an inverse correlation between MS duration and the humoral response to EBV determined by anti-EBNA-1 IgG index, which might suggest a higher immune control of EBV infection in HCMV(+) cases by mechanisms of heterologous immunity between both viruses. In addition, HCMV(+) MS patients had a higher proportion of differentiated terminal T cells as compared to HCMV(-) cases independently of other clinical characteristics, suggesting that the differentiation of the T cell compartment might be involved in the putative protective role of HCMV in MS. Evaluating the HCMV influence on the NK cell compartment, we found that chronic HCMV infection was associated to an adaptive NK cell immunophenotype, that was characterized by higher expression of NKG2C, and lower of FcRγ and PLZF in NK cells, both in healthy controls and MS patients. However, adaptive NK cell markers in patients were influenced by MS clinical form and treatment with interferon beta. Moreover, a higher NKG2C(+) expression in NK cells was related to lower MS disability in early MS patients, supporting the hypothesis that HCMV may reduce MS risk. Additionally, we observed a higher PLZF loss in HCMV(-) MS patients as compared to controls, suggesting that other factors independent to HCMV infection could induce the expression of the adaptive NK cell markers in the context of MS. Finally, we evaluated the influence of the adaptive NK cell immunophenotype on the function of these lymphocytes in MS. We found that antibody dependent cell-mediated cytotoxicity (ADCC) responses by NK cells against EBV(+) lymphoblastoid cell lines may differ in relation to MS clinical form, perceiving a lower ADCC function in primary progressive MS patients. Furthermore, in contrast to healthy controls, an adaptive immunophenotype was not associated to higher ADCC in MS. Overall, our results provides further insights on the putative protective role of HCMV in MS, suggesting that an adaptive NK cell response induced by chronic HCMV infection may be deficient in MS patients.Universitat Autònoma de Barcelona. Programa de Doctorat en Medicin

Prevalence of cardiovascular risk factors in people with epilepsy

Epilepsy has been associated with cardiovascular comorbidity. This study aimed to assess the potential association between cardiovascular risk factors (s), antiepileptic drugs (s), and etiology. A single-center retrospective epilepsy cohort from the decade of 2004-2013 was assessed. Poisson regression models with robust variance were estimated to obtain prevalence ratios () according to prescription and etiology. After excluding patients in the monotherapy group with vascular etiology or previous cardiovascular events, in the remaining 400 patients, enzyme-inducer s (s), especially phenytoin (), were associated with higher prevalence of dyslipidemia (a 1.77, p < .05), compared to valproic acid. No etiology was associated with higher prevalence of any . Patients treated with s, especially , had higher prevalence of dyslipidemia

Delayed B cell repopulation after rituximab treatment in multiple sclerosis patients with expanded adaptive natural killer cells

Background and purpose: The aim was to evaluate whether adaptive NKG2C+ natural killer (NK) cells, characterized by enhanced antibody-dependent cell cytotoxicity (ADCC), may influence time to B cell repopulation after rituximab treatment in multiple sclerosis (MS) patients. Methods: This was a prospective observational study of MS patients treated with rituximab monitoring peripheral B cells for repeated doses. B cell repopulation was defined as CD19+ cells above 2% of total lymphocytes, classifying cases according to the median time of B cell repopulation as early or late (≤9 months, >9 months, respectively). Basal NK cell immunophenotype and in vitro ADCC responses induced by rituximab were assessed by flow cytometry. Results: B cell repopulation in 38 patients (24 relapsing-remitting MS [RRMS]; 14 progressive MS) was classified as early (≤9 months, n = 19) or late (>9 months, n = 19). RRMS patients with late B cell repopulation had higher proportions of NKG2C+ NK cells compared to those with early repopulation (24.7% ± 16.2% vs. 11.3% ± 10.4%, p < 0.05), and a direct correlation between time to B cell repopulation and percentage of NKG2C+ NK cells (R 0.45, p < 0.05) was observed. RRMS cases with late repopulation compared with early repopulation had a higher secretion of tumor necrosis factor α and interferon γ by NK cells after rituximab-dependent NK cell activation. The NK cell immunophenotype appeared unrelated to B cell repopulation in progressive MS patients. Conclusions: Adaptive NKG2C+ NK cells in RRMS may be associated with delayed B cell repopulation after rituximab, a finding probably related to enhanced depletion of B cells exerted by NK-cell-mediated ADCC, pointing to the use of personalized regimens with anti-CD20 monoclonal antibody therapy in some patients

Long-term cardiovascular prognosis after transient ischemic attack: Associated predictors

OBJECTIVE: To determine long-term cardiovascular risk after TIA and to identify the factors associated with increased risk. METHODS: This was a prospective observational registry of TIA patients admitted to the emergency room of our tertiary stroke center from June 2006 to January 2016. New vascular events (NVEs) were recorded from 3 months after TIA onset until June 2017, including both stroke and nonstroke events (coronary and peripheral disease). We registered TIA etiology, age, sex, vascular risk factors, radiologic data, and clinical TIA features and analyzed these variables in relation to NVE long-term risk. RESULTS: In total, 676 patients 71.7 ± 13.7 years of age were included, with a mean follow-up of 48.8 ± 32.7 months. An NVE was detected in 173 patients (25.6%) without significant differences between event types (p = 0.84). Univariate analysis associated NVEs with etiologic subgroup, male sex, diabetes mellitus, hypertension, previous vascular disease, duration and clinical features of TIA, and signs of acute infarction. Multivariable analysis showed an independent association of NVEs with etiologic TIA subgroup, signs of acute infarction, and duration of TIA symptoms. Large artery atherosclerosis and cardioaortic embolism had the highest NVE risk, with a slightly higher percentage of nonstroke events. The small artery disease subgroup had the lowest NVE risk, with a higher percentage of stroke events. CONCLUSIONS: Etiology subgroup was the main factor determining high long-term risk of vascular events in patients with TIA. Large artery atherosclerosis carried the highest vascular risk, both nonstroke and stroke, followed by cardioaortic embolism

Long-term cardiovascular prognosis after transient ischemic attack: Associated predictors

OBJECTIVE: To determine long-term cardiovascular risk after TIA and to identify the factors associated with increased risk. METHODS: This was a prospective observational registry of TIA patients admitted to the emergency room of our tertiary stroke center from June 2006 to January 2016. New vascular events (NVEs) were recorded from 3 months after TIA onset until June 2017, including both stroke and nonstroke events (coronary and peripheral disease). We registered TIA etiology, age, sex, vascular risk factors, radiologic data, and clinical TIA features and analyzed these variables in relation to NVE long-term risk. RESULTS: In total, 676 patients 71.7 ± 13.7 years of age were included, with a mean follow-up of 48.8 ± 32.7 months. An NVE was detected in 173 patients (25.6%) without significant differences between event types (p = 0.84). Univariate analysis associated NVEs with etiologic subgroup, male sex, diabetes mellitus, hypertension, previous vascular disease, duration and clinical features of TIA, and signs of acute infarction. Multivariable analysis showed an independent association of NVEs with etiologic TIA subgroup, signs of acute infarction, and duration of TIA symptoms. Large artery atherosclerosis and cardioaortic embolism had the highest NVE risk, with a slightly higher percentage of nonstroke events. The small artery disease subgroup had the lowest NVE risk, with a higher percentage of stroke events. CONCLUSIONS: Etiology subgroup was the main factor determining high long-term risk of vascular events in patients with TIA. Large artery atherosclerosis carried the highest vascular risk, both nonstroke and stroke, followed by cardioaortic embolism

Impact of cytomegalovirus infection on B cell differentiation and cytokine production in multiple sclerosis

Altres ajuts: This work was supported by the EU FP7-MINECO Infect-ERA Program, and Red Española de Esclerosis Múltiple (REEM) from the Instituto de Salud Carlos III, the European Regional Development Fund (Grant RD16/0015/0011), and the Spanish Ministry of Economy and Competitiveness.Human cytomegalovirus (HCMV) infection has been recently associated with a low risk of multiple sclerosis (MS), yet the basis behind this observation remains uncertain. In this study, we aimed to determine in MS patients whether HCMV induces modifications in the peripheral B cell compartment. HCMV serostatus was determined in 73 MS patients (55 relapsing-remitting MS (RRMS); 18 progressive MS (PMS)) and 30 healthy controls, assessing their B cell immunophenotype and cytokine production (GM-CSF, IL-6, IL-10, and TNFα) by flow cytometry. HCMV seropositivity in untreated MS patients (n = 45) was associated with reduced switched memory B cells, contrasting with an opposite effect in PMS. Expansions of transitional B cells were observed in HCMV(+) IFNβ-treated RRMS patients but not in HCMV(−) cases (p < 0.01), suggesting that HCMV may influence the distribution of B cell subsets modulating the effects of IFNβ. Considering the B cell functional profile, HCMV(−) PMS displayed an increased secretion of proinflammatory cytokines (IL-6, TNFα) as compared to HCMV(+) PMS and RRMS cases (p < 0.001). Our study reveals an influence of HCMV infection on the phenotype and function of B cells, promoting early differentiation stages in RRMS and reducing the proinflammatory cytokine profile in advanced MS forms, which might be related with the putative protective role of this virus in MS

Low cytomegalovirus seroprevalence in early multiple sclerosis: a case for the 'hygiene hypothesis'?

BACKGROUND AND PURPOSE: Cytomegalovirus (CMV) infection has recently been associated with a lower multiple sclerosis (MS) susceptibility, although it remains controversial whether it has a protective role or is merely an epiphenomenon related to westernization and early-life viral infections. We aimed to evaluate whether CMV serostatus may differ in patients with early MS as compared with patients with non-early MS, analyzing the putative association of this virus with MS clinical course and humoral immune responses against other herpesviruses. METHODS: Multicentric analysis was undertaken of 310 patients with MS (early MS, disease duration ≤5 years, n = 127) and controls (n = 155), evaluating specific humoral responses to CMV, Epstein-Barr virus and human herpesvirus-6, as well as T-cell and natural killer (NK)-cell immunophenotypes. RESULTS: Cytomegalovirus seroprevalence in early MS was lower than in non-early MS or controls (P < 0.01), being independently associated with disease duration (odds ratio, 1.04; 95% confidence interval, 1.01-1.08, P < 0.05). CMV+ patients with MS displayed increased proportions of differentiated T-cells (CD27-CD28-, CD57+, LILRB1+) and NKG2C+ NK-cells, which were associated with a lower disability in early MS (P < 0.05). CMV+ patients with early MS had an age-related decline in serum anti-EBNA-1 antibodies (P < 0.01), but no CMV-related differences in anti-human herpesvirus-6 humoral responses. CONCLUSIONS: Low CMV seroprevalence was observed in patients with early MS. Modification of MS risk attributed to CMV might be related to the induction of differentiated T-cell and NK-cell subsets and/or modulation of Epstein-Barr virus-specific immune responses at early stages of the disease.This work was supported by grants FIS/PI14/00177,FIS/PI17/00254 and SAF 2013-49063-C2-1-R (SpanishMinistry of Economy and Competitiveness and FEDER), the EU FP7-MINECO Infect-ERA Pro-gram (PCIN-2015-191-C02-01) and Red Española de Esclerosis Múltiple from the Instituto de Salud CarlosIII, European Regional Development Fund (grant RD16/0015/0011) and Spanish Ministry of Economyand Competitiveness

Adaptive features of natural killer cells in multiple sclerosis

Human cytomegalovirus (HCMV) has been recently related with a lower susceptibility to multiple sclerosis (MS). HCMV promotes an adaptive development of NK cells bearing the CD94/NKG2C receptor with a characteristic phenotypic and functional profile. NK cells are proposed to play an immunoregulatory role in MS, and expansion of the NKG2C(+) subset was recently associated with reduced disability progression. To further explore this issue, additional adaptive NK cell markers, i.e., downregulation of FcεRIγ chain (FcRγ) and PLZF transcription factor, as well as antibody-dependent NK cell activation were assessed in controls and MS patients considering HCMV serology and clinical features. In line with previous reports, increased proportions of NKG2C(+), FcRγ(-), and PLZF(-) CD56dim NK cells were found in HCMV(+) cases. However, PLZF(-) NK cells were detected uncoupled from other adaptive markers within the CD56bright subset from HCMV(+) cases and among CD56dim NK cells from HCMV(-) MS patients, suggesting an additional effect of HCMV-independent factors in PLZF downregulation. Interferon-β therapy was associated with lower proportions of FcRγ(-) CD56dim NK cells in HCMV(+) and increased PLZF(-) CD56bright NK cells in HCMV(-) patients, pointing out to an influence of the cytokine on the expression of adaptive NK cell-associated markers. In addition, proportions of NKG2C(+) and FcRγ(-) NK cells differed in progressive MS patients as compared to controls and other clinical forms. Remarkably, an adaptive NK cell phenotype did not directly correlate with enhanced antibody-triggered degranulation and TNFα production in MS in contrast to controls. Altogether, our results provide novel insights into the putative influence of HCMV and adaptive NK cells in MS.This work was supported by grants FIS/PI17/00254, SAF 2016-80363-C2-1-R (Spanish Ministry of Economy and Competitiveness and FEDER), the EU FP7-MINECO Infect-ERA Program (PCIN-2015-191-C02-01), and Red Española de Esclerosis Múltiple (REEM) from the Instituto de Salud Carlos III, the European Regional Development Fund (Grant RD16/0015/0011), and the Spanish Ministry of Economy and Competitiveness