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Parvovirus B19 infection is associated with a wide range of clinical manifestations, from asymptomatic to severe neurological disorders. Its major clinical symptoms, fever and rash, are common to multiple viruses, and laboratory tests to detect B19 are frequently not available. Thus, the impact of B19 on public health remains unclear. We report the case of a 38-day old girl admitted to São Paulo Clinical Hospital, Brazil, with an initial diagnosis of bacterial meningitis, seizures, and acute hydrocephalus. Antibiotic therapy was maintained for one week after admission and discontinued after negative laboratory results were obtained. Nine days after symptoms onset, a cerebral spinal fluid (CSF) sample revealed persistent pleocytosis. The complete B19 complete genome was subsequently identified in her CSF by a metagenomic next-generation sequencing approach. This report highlights the possible involvement of B19 in the occurrence of acute neurological manifestations and emphasizes that its possible involvement might be better revealed by the use of metagenomic technology to detect viral agents in clinical situations of unknown or uncertain etiology.
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Yellow fever (YF) is a mosquito-transmitted viral disease that causes tens of thousands of deaths each year despite the long-standing deployment of an effective vaccine. In its most severe form, YF manifests as a hemorrhagic fever that causes severe damage to visceral organs. Although coagulopathy is a defining feature of severe YF in humans, the mechanism by which it develops remains uncertain. Hepatocytes are a major target of yellow fever virus (YFV) infection, and the coagulopathy in severe YF has long been attributed to massive hepatocyte infection and destruction that results in a defect in clotting factor synthesis. However, when we analyzed blood from Brazilian patients with severe YF, we found high concentrations of plasma D-dimer, a fibrin split product, suggestive of a concurrent consumptive process. To define the relationship between coagulopathy and hepatocellular tropism, we compared infection and disease in Fah-/-, Rag2-/-, and Il2rɣ-/- mice engrafted with human hepatocytes (hFRG mice) and rhesus macaques using a highly pathogenic African YFV strain. YFV infection of macaques and hFRG mice caused substantial hepatocyte infection, liver damage, and coagulopathy as defined by virological, clinical, and pathological criteria. However, only macaques developed a consumptive coagulopathy whereas YFV-infected hFRG mice did not. Thus, infection of cell types other than hepatocytes likely contributes to the consumptive coagulopathy associated with severe YF in primates and humans. These findings expand our understanding of viral hemorrhagic disease and associated coagulopathy and suggest directions for clinical management of severe YF cases.
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Coagulación Intravascular Diseminada/virología , Hepatopatías/virología , Tropismo Viral/fisiología , Fiebre Amarilla/fisiopatología , Virus de la Fiebre Amarilla/fisiología , Animales , Modelos Animales de Enfermedad , Coagulación Intravascular Diseminada/sangre , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Hepatocitos/trasplante , Hepatocitos/virología , Humanos , Hepatopatías/fisiopatología , Macaca mulatta , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Fiebre Amarilla/complicaciones , Fiebre Amarilla/virologíaRESUMEN
Exposure to dengue virus (DENV) is thought to elicit lifelong immunity, mediated by DENV-neutralizing antibodies (nAbs). However, Abs generated by primary infections confer serotype-specific protection, and immunity against other serotypes develops only after subsequent infections. Accordingly, the induction of these nAb responses acquired after serial DENV infections has been a long-sought-after goal for vaccination. Nonetheless, it is still unclear if tetravalent vaccines can elicit or recall nAbs. In this study, we have characterized the responses from a volunteer who had been previously exposed to DENV and was immunized with the live attenuated tetravalent vaccine Butantan-DV, developed by the NIH and Butantan Institute. Eleven days after vaccination, we observed an â¼70-fold expansion of the plasmablast population. We generated 21 monoclonal Abs (MAbs) from singly sorted plasmablasts. These MAbs were the result of clonal expansions and had significant levels of somatic hypermutation (SHM). Nineteen MAbs (90.5%) neutralized at least one DENV serotype at concentrations of 1 µg/ml or less; 6 of the 21 MAbs neutralized three or more serotypes. Despite the tetravalent composition of the vaccine, we observed a neutralization bias in the induced repertoire: DENV3 was targeted by 18 of the 19 neutralizing MAbs (nMAbs). Furthermore, the P3D05 nMAb neutralized DENV3 with extraordinary potency (concentration to achieve half-maximal neutralization [Neut50] = 0.03 µg/ml). Thus, the Butantan-DV vaccine engendered a mature, antigen-selected B cell repertoire. Our results suggest that preexisting responses elicited by a previous DENV3 infection were recalled by immunization.IMPORTANCE The dengue epidemic presents a global public health challenge that causes widespread economic burden and remains largely unchecked by existing control strategies. Successful control of the dengue epidemic will require effective prophylactic and therapeutic interventions. Several vaccine clinical efficacy trials are approaching completion, and the chances that one or more live attenuated tetravalent vaccines (LATVs) will be introduced worldwide is higher than ever. While it is widely accepted that dengue virus (DENV)-neutralizing antibody (nAb) titers are associated with protection, the Ab repertoire induced by LATVs remain uncharacterized. Here, we describe the isolation of potent (Neut50 < 0.1 µg/ml) nAbs from a DENV-seropositive volunteer immunized with the tetravalent vaccine Butantan-DV, which is currently in phase III trials.
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Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra el Dengue/inmunología , Virus del Dengue/inmunología , Células Plasmáticas/inmunología , Adulto , Vacunas contra el Dengue/administración & dosificación , Femenino , Células HEK293 , Humanos , Masculino , National Institutes of Health (U.S.) , Estados UnidosRESUMEN
While progress has been made in characterizing humoral immunity to Zika virus (ZIKV) in humans, little is known regarding the corresponding T cell responses to ZIKV. Here, we investigate the kinetics and viral epitopes targeted by T cells responding to ZIKV and address the critical question of whether preexisting dengue virus (DENV) T cell immunity modulates these responses. We find that memory T cell responses elicited by prior infection with DENV or vaccination with tetravalent dengue attenuated vaccines (TDLAV) recognize ZIKV-derived peptides. This cross-reactivity is explained by the sequence similarity of the two viruses, as the ZIKV peptides recognized by DENV-elicited memory T cells are identical or highly conserved in DENV and ZIKV. DENV exposure prior to ZIKV infection also influences the timing and magnitude of the T cell response. ZIKV-reactive T cells in the acute phase of infection are detected earlier and in greater magnitude in DENV-immune patients. Conversely, the frequency of ZIKV-reactive T cells continues to rise in the convalescent phase in DENV-naive donors but declines in DENV-preexposed donors, compatible with more efficient control of ZIKV replication and/or clearance of ZIKV antigen. The quality of responses is also influenced by previous DENV exposure, and ZIKV-specific CD8 T cells from DENV-preexposed donors selectively upregulated granzyme B and PD1, unlike DENV-naive donors. Finally, we discovered that ZIKV structural proteins (E, prM, and C) are major targets of both the CD4 and CD8 T cell responses, whereas DENV T cell epitopes are found primarily in nonstructural proteins.IMPORTANCE The issue of potential ZIKV and DENV cross-reactivity and how preexisting DENV T cell immunity modulates Zika T cell responses is of great relevance, as the two viruses often cocirculate and Zika virus has been spreading in geographical regions where DENV is endemic or hyperendemic. Our data show that memory T cell responses elicited by prior infection with DENV recognize ZIKV-derived peptides and that DENV exposure prior to ZIKV infection influences the timing, magnitude, and quality of the T cell response. Additionally, we show that ZIKV-specific responses target different proteins than DENV-specific responses, pointing toward important implications for vaccine design against this global threat.
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Virus del Dengue/inmunología , Linfocitos T/inmunología , Infección por el Virus Zika/inmunología , Virus Zika/inmunología , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios de Cohortes , Reacciones Cruzadas , Vacunas contra el Dengue/inmunología , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vacunas Atenuadas/inmunología , Adulto JovenRESUMEN
Development of vaccines against mosquito-borne Flaviviruses is complicated by the occurrence of antibody-dependent enhancement (ADE), which can increase disease severity. Long-term delivery of neutralizing antibodies (nAbs) has the potential to effectively block infection and represents an alternative to vaccination. The risk of ADE may be avoided by using prophylactic nAbs harboring amino acid mutations L234A and L235A (LALA) in the immunoglobulin G (IgG) constant region. Here, we used recombinant adeno-associated viruses (rAAVs) to deliver the anti-dengue virus 3 (DENV3) nAb P3D05. While the administration of rAAV-P3D05-rhesus immunoglobulin G1 (rhIgG1)-LALA to rhesus macaques engendered DENV3-neutralizing activity in serum, it did not prevent infection. The emergence of viremia following DENV3 challenge was delayed by 3-6 days in the rAAV-treated group, and replicating virus contained the envelope mutation K64R. This neutralization-resistant variant was also confirmed by virus outgrowth experiments in vitro. By delivering P3D05 with unmutated Fc sequences, we further demonstrated that DENV3 also evaded wild-type nAb prophylaxis, and serum viral loads appeared to be higher in the presence of low levels of unmutated P3D05-rhIgG1. Our study shows that a vectored approach for long-term delivery of nAbs with the LALA mutations is promising, but prophylaxis using a single nAb is likely insufficient at preventing DENV infection and replication.
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Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Virus del Dengue/inmunología , Dependovirus/genética , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Macaca mulatta , MasculinoRESUMEN
BACKGROUND: Endometriosis is a multifactorial gynecological disease characterized by the presence of functional endometrium-like tissue in ectopic sites. Several studies have focused on elucidating the immunological, endocrine, environmental and genetic factors involved in endometriosis. However, its pathogenesis is still unclear. METHODS: High-resolution comparative genomic hybridization was applied to screen for genomic imbalances in laser microdissected stromal and epithelial cells from 20 endometriotic lesions and three samples of eutopic endometrium derived from eight patients. The expression of seven stemness-related markers (CD9, CD13, CD24, CD34, CD133, CD117/c-Kit and Oct-4) in endometrial tissue samples was evaluated by immunohistochemistry. RESULTS: Samples of eutopic endometrium showed normal genomic profiles. In ectopic tissues, an average of 68 genomic imbalances was detected per sample. DNA losses were more frequently detected and involved mainly 3p, 5q, 7p, 9p, 11q, 16q, 18q and 19q. Many of the genomic imbalances detected were common to endometriotic stroma and epithelia and also among different endometriotic sites from the same patient. These findings suggested a clonal origin of the endometriotic cells and the putative involvement of stem cells. Positive immunostaining for CD9, CD34, c-Kit and Oct-4 markers was detected in isolated epithelial and/or stromal cells in eutopic and ectopic endometrium in the majority of cases. CONCLUSIONS: The presence of shared genomic alterations in stromal and epithelial cells from different anatomical sites of the same patient and the expression of stemness-related markers suggested that endometriosis arises as a clonal proliferation with the putative involvement of stem cells.
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Células Madre Adultas/metabolismo , Antígenos CD/metabolismo , Aberraciones Cromosómicas , Endometriosis/metabolismo , Endometrio/metabolismo , Regulación de la Expresión Génica , Adulto , Células Madre Adultas/patología , Antígenos CD/genética , Biomarcadores/metabolismo , Deleción Cromosómica , Células Clonales/metabolismo , Células Clonales/patología , Hibridación Genómica Comparativa , Endometriosis/diagnóstico , Endometriosis/patología , Endometriosis/cirugía , Endometrio/patología , Endometrio/cirugía , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Enfermedades Intestinales/diagnóstico , Enfermedades Intestinales/metabolismo , Enfermedades Intestinales/patología , Enfermedades Intestinales/cirugía , Captura por Microdisección con Láser , Células del Estroma/metabolismo , Células del Estroma/patologíaRESUMEN
An effective vaccine against the dengue virus (DENV) should induce a balanced, long-lasting antibody (Ab) response against all four viral serotypes. The burst of plasmablasts in the peripheral blood after vaccination may reflect enriched vaccine-specific Ab secreting cells. Here we characterize the acute plasmablast responses from naïve and DENV-exposed individuals following immunization with the live attenuated tetravalent (LAT) Butantan DENV vaccine (Butantan-DV). The frequency of circulating plasmablasts was determined by flow cytometric analysis of fresh whole blood specimens collected from 40 participants enrolled in the Phase II Butantan-DV clinical trial (NCT01696422) before and after (days 6, 12, 15 and 22) vaccination. We observed a peak in the number of circulating plasmablast at day 15 after vaccination in both the DENV naïve and the DENV-exposed vaccinees. DENV-exposed vaccinees experienced a significantly higher plasmablast expansion. In the DENV-naïve vaccinees, plasmablasts persisted for approximately three weeks longer than among DENV-exposed volunteers. Our findings indicate that the Butantan-DV can induce plasmablast responses in both DENV-naïve and DENV-exposed individuals and demonstrate the influence of pre-existing DENV immunity on Butantan DV-induced B-cell responses.
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Vacunas contra el Dengue , Virus del Dengue , Anticuerpos Antivirales , Brasil , Humanos , Vacunas AtenuadasRESUMEN
BACKGROUND: The Butantan Institute has manufactured a lyophilised tetravalent live-attenuated dengue vaccine Butantan-DV, which is analogous to the US National Institutes of Health (NIH) TV003 admixture. We aimed to assess the safety and immunogenicity of Butantan-DV. METHODS: We did a two-step, double-blind, randomised placebo-controlled phase 2 trial at two clinical sites in São Paulo, Brazil. We recruited healthy volunteers aged 18-59 years; pregnant women, individuals with a history of neurological, heart, lung, liver or kidney disease, diabetes, cancer, or autoimmune diseases, and individuals with HIV or hepatitis C were excluded. Step A was designed as a small bridge-study between Butantan-DV and TV003 in DENV-naive participants. In step A, we planned to randomly assign 50 dengue virus (DENV)-naive individuals to receive two doses of Butantan-DV, TV003, or placebo, given 6 months apart. In step B, we planned to randomly assign 250 participants (DENV-naive and DENV-exposed) to receive one dose of Butantan-DV or placebo. Participants were randomly assigned, by computer-generated block randomisation (block sizes of five); participants in step A were randomly assigned (2:2:1) to receive Butantan-DV, TV003, or placebo and participants in step B were randomly assigned (4:1) to receive Butantan-DV or placebo. Participants and study staff were unaware of treatment allocation. The primary safety outcome was the frequency of solicited and unsolicited local and systemic adverse reactions within 21 days of the first vaccination, analysed by intention to treat. The primary immunogenicity outcome was seroconversion rates of the DENV-1-4 serotypes measured 91 days after the first vaccination, analysed in the per-protocol population, which included all participants in step A, and all participants included in step B who completed all study visits with serology sample collection. This trial is registered with ClinicalTrials.gov, NCT01696422. FINDINGS: Between Nov 5, 2013, and Sept 21, 2015, 300 individuals were enrolled and randomly assigned: 155 (52%) DENV-naive participants and 145 (48%) DENV-exposed participants. Of the 155 DENV-naive participants, 97 (63%) received Butantan-DV, 17 (11%) received TV003, and 41 (27%) received placebo. Of the 145 DENV-exposed participants, 113 (78%) received Butantan-DV, three (2%) received TV003, and 29 (20%) received placebo. Butantan-DV and TV003 were both immunogenic, well-tolerated, and no serious adverse reactions were observed. In step A, rash was the most frequent adverse event (16 [845] of 19 participants in the Butantan-DV group and 13 [76%] of 17 participants in the TV003 group). Viraemia was similar between the Butantan-DV and TV003 groups. Of the 85 DENV-naive participants in the Butantan-DV group who attended all visits for sample collection for seroconversion analysis and thus were included in the per-protocol analysis population, 74 (87%) achieved seroconversion to DENV-1, 78 (92%) to DENV-2, 65 (76%) to DENV-3, and 76 (89%) to DENV-4. Of the 101 DENV-exposed participants in the Butantan-DV group who attended all visits for sample collection for seroconversion analysis, 82 (81%) achieved seroconversion to DENV-1, 79 (78%) to DENV-2, 83 (82%) to DENV-3, and 78 (77%) to DENV-4. INTERPRETATION: Butantan-DV and TV003 were safe and induced robust, balanced neutralising antibody responses against the four DENV serotypes. Efficacy evaluation of the Butantan-DV vaccine is ongoing. FUNDING: Intramural Research Program US NIH National Institute of Allergy and Infectious Diseases, Brazilian National Bank for Economic and Social Development, Fundação de Amparo à Pesquisa do Estado de São Paulo, and Fundação Butantan.
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Vacunas contra el Dengue/inmunología , Virus del Dengue/inmunología , Inmunogenicidad Vacunal , Vacunas Atenuadas/inmunología , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Brasil , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Seroconversión , Vacunación , Adulto JovenRESUMEN
Myelodysplastic syndrome (MDS) is a rare hematological malignancy in children. It was performed FISH analysis in 19 pediatric MDS patients to investigate deletions involving the PPARgamma and TP53 genes. Significant losses in the PPARgamma gene and deletions in the tumor suppressor gene TP53 were observed in 17 and 18 cases, respectively. Using quantitative RT-PCR, it was detected PPARgamma transcript downexpression in a subset of these cases. G-banding analysis revealed 17p deletions in a small number of these cases. One MDS therapy-related patient had neither a loss of PPARgamma nor TP53. These data suggest that the PPARgamma and TP53 genes may be candidates for molecular markers in pediatric MDS, and that these potentially recurrent deletions could contribute to the identification of therapeutic approaches in primary pediatric MDS.
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Eliminación de Gen , Síndromes Mielodisplásicos/genética , PPAR gamma/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Niño , Preescolar , Bandeo Cromosómico , Femenino , Humanos , Hibridación Fluorescente in Situ , Lactante , Cariotipificación , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
BACKGROUND: HER-2 gene testing has become an integral part of breast cancer patient diagnosis. The most commonly used assay in the clinical setting for evaluating HER-2 status is immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). These procedures permit correlation between HER-2 expression and morphological features. However, FISH signals are labile and fade over time, making post-revision of the tumor difficult. CISH (chromogenic in situ hybridization) is an alternative procedure, with certain advantages, although still limited as a diagnostic tool in breast carcinomas. METHODS: To elucidate the molecular profile of HER-2 status, mRNA and protein expression in 75 invasive breast carcinomas were analyzed by real time quantitative RT-PCR (qRT-PCR) and IHC, respectively. Amplifications were evaluated in 43 of these cases by CISH and in 11 by FISH. RESULTS: The concordance rate between IHC and qRT-PCR results was 78.9%, and 94.6% for qRT-PCR and CISH. Intratumoral heterogeneity of HER-2 status was identified in three cases by CISH. The results of the three procedures were compared and showed a concordance rate of 83.8%; higher discordances were observed in 0 or 1+ immunostaining cases, which showed high-level amplification (15.4%) and HER-2 transcript overexpression (20%). Moreover, 2+ immunostaining cases presented nonamplified status (50%) by CISH and HER-2 downexpression (38.5%) by qRT-PCR. In general, concordance occurred between qRT-PCR and CISH results. A high concordance was observed between CISH/qRT-PCR and FISH. Comparisons with clinicopathological data revealed a significant association between HER-2 downexpression and the involvement of less than four lymph nodes (P = 0.0350). CONCLUSION: Based on these findings, qRT-PCR was more precise and reproducible than IHC. Furthermore, CISH was revealed as an alternative and useful procedure for investigating amplifications involving the HER-2 gene.
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Neoplasias de la Mama/patología , Hibridación Fluorescente in Situ/métodos , Receptor ErbB-2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Femenino , Amplificación de Genes , Dosificación de Gen , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Estadificación de Neoplasias , Receptor ErbB-2/metabolismo , Reproducibilidad de los ResultadosRESUMEN
The objective of the present study was to test the ability of OSU-03012 (2-amino-N-[4-[5-phenanthren-2-yl-3-(trifluoromethyl)pyrazol-1-yl]phenyl]acetamide), a novel and potent celecoxib-derivative, to impair endometriosis progression in in vitro and in vivo models based on its ability to indirectly block Y-box-binding protein 1 (YB-1) function. 12Z human endometriotic epithelial cells and sexually mature female C57BL/6J mice were treated with OSU-03012. Cellular proliferation was quantified by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromid assay. Expression of YB-1 and phosphorylated YB-1 in 12Z cells and endometriotic lesions was evaluated by Western blotting and immunohistochemistry (IHC). The IHC for proliferating cell nuclear antigen was performed. OSU-03012 treatment resulted in decreased YB-1 and its phosphorylated form in both in vitro and in vivo models. Endometriotic lesion size was significantly reduced in OSU-03012-treated mice (27.6 ± 4.0 mm3) compared to those from the control group (50.5 ± 6.9 mm3, P < .0001). A significant reduction in endometriotic epithelial cell proliferation was observed in endometriotic lesions exposed to OSU-03012 treatment ( P = .0346). In conclusion, targeting YB-1 via OSU-03012 showed a potent antiproliferative effect on endometriotic epithelial cells in vitro and in a mouse model of disease.
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Zika virus (ZIKV) is a mosquito-borne flavivirus of significant public health concern. In the summer of 2016, ZIKV was first detected in the contiguous United States. Here we present one of the first cases of a locally acquired ZIKV infection in a dengue-naïve individual. We collected blood from a female with a maculopapular rash at day (D) 5 and D7 post onset of symptoms (POS) and we continued weekly blood draws out to D148 POS. To establish the ontogeny of the immune response against ZIKV, lymphocytes and plasma were analyzed in a longitudinal fashion. The plasmablast response peaked at D7 POS (19.6% of CD19+ B-cells) and was undetectable by D15 POS. ZIKV-specific IgM was present at D5 POS, peaked between D15 and D21 POS, and subsequently decreased. The ZIKV-specific IgG response, however, was not detected until D15 POS and continued to increase after that. Interestingly, even though the patient had never been infected with dengue virus (DENV), cross-reactive IgM and IgG binding against each of the four DENV serotypes could be detected. The highest plasma neutralization activity against ZIKV peaked between D15 and D21 POS, and even though DENV binding antibodies were present in the plasma of the patient, there was neither neutralization nor antibody dependent enhancement (ADE) of DENV. Interestingly, ADE against ZIKV arose at D48 POS and continued until the end of the study. CD4+ and CD8+ T-cells recognized ZIKV-NS2A and ZIKV-E, respectively. The tetramer positive CD8+ T-cell response peaked at D21 POS with elevated levels persisting for months. In summary, this is the first study to establish the timing of the ontogeny of the immune response against ZIKV.
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Anticuerpos Antivirales/sangre , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Virus Zika/inmunología , Adulto , Anticuerpos Antivirales/inmunología , Reacciones Cruzadas/inmunología , Virus del Dengue/inmunología , Brotes de Enfermedades , Exantema/virología , Femenino , Florida , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , ARN Viral/genética , Proteínas del Envoltorio Viral/inmunología , Virus Zika/genética , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virologíaRESUMEN
The isolation of neutralizing monoclonal antibodies (nmAbs) against the Zika virus (ZIKV) might lead to novel preventative strategies for infections in at-risk individuals, primarily pregnant women. Here we describe the characterization of human mAbs from the plasmablasts of an acutely infected patient. One of the 18 mAbs had the unusual feature of binding to and neutralizing ZIKV despite not appearing to have been diversified by affinity maturation. This mAb neutralized ZIKV (Neut50 ~ 2 µg/ml) but did not react with any of the four dengue virus serotypes. Except for the expected junctional diversity created by the joining of the V-(D)-J genes, there was no deviation from immunoglobulin germline genes. This is a rare example of a human mAb with neutralizing activity in the absence of detectable somatic hypermutation. Importantly, binding of this mAb to ZIKV was specifically inhibited by human plasma from ZIKV-exposed individuals, suggesting that it may be of value in a diagnostic setting.
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Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Mutación de Línea Germinal , Epítopos Inmunodominantes/inmunología , Infección por el Virus Zika/inmunología , Virus Zika , Secuencia de Aminoácidos , Anticuerpos Monoclonales , Anticuerpos Neutralizantes/genética , Anticuerpos Antivirales/genética , Citometría de Flujo , Humanos , Inmunoglobulina G , Masculino , Persona de Mediana Edad , Infección por el Virus Zika/sangre , Infección por el Virus Zika/virologíaRESUMEN
Therapies to prevent maternal Zika virus (ZIKV) infection and its subsequent fetal developmental complications are urgently required. We isolated three potent ZIKV-neutralizing monoclonal antibodies (nmAbs) from the plasmablasts of a ZIKV-infected patient-SMZAb1, SMZAb2, and SMZAb5-directed against two different domains of the virus. We engineered these nmAbs with Fc LALA mutations that abrogate Fcγ receptor binding, thus eliminating potential therapy-mediated antibody-dependent enhancement. We administered a cocktail of these three nmAbs to nonhuman primates 1 day before challenge with ZIKV and demonstrated that the nmAbs completely prevented viremia in serum after challenge. Given that numerous antibodies have exceptional safety profiles in humans, the cocktail described here could be rapidly developed to protect uninfected pregnant women and their fetuses.
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Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/uso terapéutico , Infección por el Virus Zika/tratamiento farmacológico , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/farmacología , Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Neutralizantes/farmacología , Humanos , Inmunidad Humoral/efectos de los fármacos , Macaca , Carga Viral/efectos de los fármacos , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virologíaRESUMEN
BACKGROUND: Dengue is a major public health problem worldwide. Assessment of adaptive immunity is important to understanding immunopathology and to define correlates of protection against dengue virus (DENV). To enable global assessment of CD4+ T cell responses, we mapped HLA-DRB1-restricted DENV-specific CD4+ T cell epitopes in individuals previously exposed to DENV in the general population of the dengue-endemic region of Managua, Nicaragua. METHODS: HLA class II epitopes in the population of Managua were identified by an in vitro IFNγ ELISPOT assay. CD4+ T cells purified by magnetic bead negative selection were stimulated with HLA-matched epitope pools in the presence of autologous antigen-presenting cells, followed by pool deconvolution to identify specific epitopes. The epitopes identified in this study were combined with those previously identified in the DENV endemic region of Sri Lanka, to generate a "megapool" (MP) consisting of 180 peptides specifically designed to achieve balanced HLA and DENV serotype coverage. The DENV CD4MP180 was validated by intracellular cytokine staining assays. RESULTS: We detected responses directed against a total of 431 epitopes, representing all 4 DENV serotypes, restricted by 15 different HLA-DRB1 alleles. The responses were associated with a similar pattern of protein immunodominance, overall higher magnitude of responses, as compared to what was observed previously in the Sri Lanka region. Based on these epitope mapping studies, we designed a DENV CD4 MP180 with higher and more consistent coverage, which allowed the detection of CD4+ T cell DENV responses ex vivo in various cohorts of DENV exposed donors worldwide, including donors from Nicaragua, Brazil, Singapore, Sri Lanka, and U.S. domestic flavivirus-naïve subjects immunized with Tetravalent Dengue Live-Attenuated Vaccine (TV005). This broad reactivity reflects that the 21 HLA-DRB1 alleles analyzed in this and previous studies account for more than 80% of alleles present with a phenotypic frequency ≥5% worldwide, corresponding to 92% phenotypic coverage of the general population (i.e., 92% of individuals express at least one of these alleles). CONCLUSION: The DENV CD4 MP180 can be utilized to measure ex vivo responses to DENV irrespective of geographical location.
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OBJECTIVE: The objective of this study is the evaluation of serum YB-1 levels in the diagnosis of endometriosis. STUDY DESIGN: Serum samples of 12 patients with histologically confirmed endometriosis and of 10 control patients were collected. Western blot analysis was used to assess serum YB-1 levels. Groups were compared with Student's t-test or, if not normally distributed, with the Mann-Whitney test. Sensitivity and specificity for the potential diagnostic performance of serum YB-1 were assessed by receiver operating characteristic (ROC) curves. RESULTS: Serum YB-1 levels were significantly higher in patients with endometriosis (=0.004). The area under the curve was 0.867 (95% confidence interval 0.714-1.019) with sensitivity and specificity of 83.3% and 70% respectively. CONCLUSIONS: Serum YB-1 levels in patients with endometriosis are significantly higher compared to control patients and may be used as a potential diagnostic biomarker for endometriosis.
Asunto(s)
Endometriosis/sangre , Enfermedades del Ovario/sangre , Regulación hacia Arriba , Proteína 1 de Unión a la Caja Y/sangre , Adulto , Biomarcadores/sangre , Western Blotting , Endometriosis/diagnóstico , Endometriosis/cirugía , Femenino , Humanos , Enfermedades del Ovario/diagnóstico , Enfermedades del Ovario/cirugía , Curva ROC , Sensibilidad y EspecificidadRESUMEN
BACKGROUND/AIMS: The neural cell adhesion molecule L1CAM is a transmembrane glycoprotein abnormally expressed in tumors and previously associated with cell proliferation, adhesion and invasion, as well as neurite outgrowth in endometriosis. Being an attractive target molecule for antibody-based therapy, the present study assessed the ability of the monoclonal anti-L1 antibody (anti-L1 mAb) to impair the development of endometriotic lesions in vivo and endometriosis-associated nerve fiber growth. METHODS AND RESULTS: Endometriosis was experimentally induced in sexually mature B6C3F1 (n=34) and CD-1 nude (n=21) mice by autologous and heterologous transplantation, respectively, of endometrial fragments into the peritoneal cavity. Transplantation was confirmed four weeks post-surgery by in vivo magnetic resonance imaging and laparotomy, respectively. Mice were then intraperitoneally injected with anti-L1 mAb or an IgG isotype control antibody twice weekly, over a period of four weeks. Upon treatment completion, mice were sacrificed and endometrial implants were excised, measured and fixed. Endometriosis was histologically confirmed and L1CAM was detected by immunohistochemistry. Endometriotic lesion size was significantly reduced in anti-L1-treated B6C3F1 and CD-1 nude mice compared to mice treated with control antibody (P<0.05). Accordingly, a decreased number of PCNA positive epithelial and stromal cells was detected in autologously and heterologously induced endometriotic lesions exposed to anti-L1 mAb treatment. Anti-L1-treated mice also presented a diminished number of intraperitoneal adhesions at implantation sites compared with controls. Furthermore, a double-blind counting of anti-neurofilament L stained nerves revealed significantly reduced nerve density within peritoneal lesions in anti-L1 treated B6C3F1 mice (P=0.0039). CONCLUSIONS: Local anti-L1 mAb treatment suppressed endometriosis growth in B6C3F1 and CD-1 nude mice and exerted a potent anti-neurogenic effect on induced endometriotic lesions in vivo. The findings of this preliminary study in mice provide a strong basis for further testing in in vivo models.