251 research outputs found
Multi-Scale In Vivo Systems Analysis Reveals the Influence of Immune Cells on TNF-α-Induced Apoptosis in the Intestinal Epithelium
Intestinal epithelial cells exist within a complex environment that affects how they interpret and respond to stimuli. We have applied a multi-scale in vivo systems approach to understand how intestinal immune cells communicate with epithelial cells to regulate responses to inflammatory signals. Multivariate modeling analysis of a large dataset composed of phospho-signals, cytokines, and immune cell populations within the intestine revealed an intimate relationship between immune cells and the epithelial response to TNF-α. Ablation of lymphocytes in the intestine prompted a decrease in the expression of MCP-1, which in turn increased the steady state number of intestinal plasmacytoid dendritic cells (pDCs). This change in the immune compartment affected the intestinal cytokine milieu and subsequent epithelial cell signaling network, with cells becoming hypersensitive to TNF-α-induced apoptosis in a way that could be predicted by mathematical modeling. In summary, we have uncovered a novel cellular network that regulates the response of intestinal epithelial cells to inflammatory stimuli in an in vivo setting
Neutrophils Suppress Intraluminal NK Cell-Mediated Tumor Cell Clearance and Enhance Extravasation of Disseminated Carcinoma Cells
Immune cells promote the initial metastatic dissemination of carcinoma cells from primary tumors. In contrast to their well-studied functions in the initial stages of metastasis, the specific roles of immunocytes in facilitating progression through the critical later steps of the invasion–metastasis cascade remain poorly understood. Here, we define novel functions of neutrophils in promoting intraluminal survival and extravasation at sites of metastatic dissemination. We show that CD11b+/Ly6G+neutrophils enhance metastasis formation via two distinct mechanisms. First, neutrophils inhibit natural killer cell function, which leads to a significant increase in the intraluminal survival time of tumor cells. Thereafter, neutrophils operate to facilitate extravasation of tumor cells through the secretion of IL1β and matrix metalloproteinases. These results identify neutrophils as key regulators of intraluminal survival and extravasation through their cross-talk with host cells and disseminating carcinoma cells. SIGNIFICANCE: This study provides important insights into the systemic contributions of neutrophils to cancer metastasis by identifying how neutrophils facilitate intermediate steps of the invasion–metastasis cascade. We demonstrate that neutrophils suppress natural killer cell activity and increase extravasation of tumor cells.Human Frontier Science Program (Strasbourg, France) (fellowship LT00728/2008-L)Charles King Trust FoundationMassachusetts Institute of Technology. Ludwig Center for Cancer ResearchCancer Research Institute (New York, N.Y.) (Irvington Fellowship)National Institutes of Health (U.S.) (grant P01 CA080111)National Institutes of Health (U.S.) (grant CA163109
How hepatitis C virus modifies the immunological profile of Sjögren syndrome: analysis of 783 patients.
Introduction: We conducted a study to analyze how infection by hepatitis C virus (HCV) may influence the immunological serum pattern of patients with Sjögren syndrome (SS). Methods: Since 1994, we have tested serum HCV-IgG antibodies in 783 patients with SS diagnosed according to the 1993 European classification criteria. The immunological profile at diagnosis was compared according to the presence or absence of HCV. Results: Of the 783 patients with SS, 105 (13.4 %) tested positive for HCV-IgG antibodies (88 females, 17 males,mean age at SS diagnosis: 62.9 years). Multivariate analysis showed that patients with SS-HCV had a higher mean age and a higher frequency of low C3/C4 levels, cryoglobulins, and hematological neoplasia compared with patients without HCV. The frequency of anti-La antibodies compared with anti-Ro antibodies was higher in patients with SS-HCV (17 % vs. 15 %) and lower in patients without HCV infection (30 % vs. 43 %). The frequency of concomitant detection of the three main cryoglobulin-related markers (cryoglobulins, rheumatoid factor activity, and C4 consumption) was threefold higher in patients with SS-HCV compared with patients without HCV. SS-HCV patients with genotype 1b showed the highest frequencies of immunological abnormalities related to cryoglobulins and the lowest frequencies of anti-Ro/La antibodies. Conclusions: We found HCV infection in 13 % of a large series of Spanish patients with SS. The HCV-driven autoimmune response was characterized by a lower frequency of anti-Ro/La antibodies, an abnormal predominance of anti-La among anti-Ro antibodies, and a higher frequency of cryoglobulinemic-related immunological markers in comparison with patients without HCV infection. This immunological pattern may contribute to the poor outcomes found in patients with SS-HCV
Seroprevalencia de anticuerpos contra el virus de hepatitis C (VHC) en trabajadoras sexuales que acuden a un Centro de Referencia de Infecciones de Transmisión Sexual (CERITSS) de la ciudad de Iquitos, Perú
Introducción: los principales factores de riesgo descritos para contraer la infección por el virus de la hepatitis C (VHC) son antecedentes de transfusión sanguÃnea y uso de droga endovenosa; el riesgo por transmisión sexual es controversial. Existen pocos estudios de VHC en trabajadoras sexuales (TS) en el Perú, encontrando bajas prevalencias de VHC (0-1%). El presente estudio se ha realizado en Iquitos, una ciudad en la selva peruana, en donde existe gran comercio sexual y la prevalencia de HIV/SIDA y otras Infecciones de Transmisión Sexual (ITS) es alta.Â
Objetivo: determinar la seroprevalencia de anticuerpos contra el VHC en TS de la ciudad de Iquitos atendidas en un Centro Especializado de Referencia de Infecciones de transmisión sexual (CERITSS) e identificar los factores de riesgo asociados a esta.Â
Material y métodos: es un estudio de corte transversal en TS quienes acudieron a su control periódico al CERITSS San Juan entre mayo 2003 a enero 2004. Una encuesta clÃnica-epidemiológica fue utilizada para determinar la frecuencia de factores de riesgo para adquirir la infección por VHC. Para determinar la presencia de anticuerpos contra el VHC, se utilizó la prueba de enzima inmunoensayo (EIA); todos los resultados positivos fueron confirmados con la prueba inmunoblot recombinante (RIBA).Â
Resultados: cuatro de las 200 TS enroladas en el estudio fueron positivos para la prueba EIA, todas ellas tuvieron resultados positivos de RIBA (prevalencia de 2%, IC95% 0,06-3,94%). Estas 4 TS reportaron ser naturales de Iquitos, tener mas de 5 años de trabajo sexual, reportaron un bajo uso de condón (<50%). Tres de ellas reportaron haber tenido mas de 9 parejas/ dÃa, realizar trabajo sexual bajo efecto del alcohol y tener sexo anal frecuentemente. Ninguna refirió transfusiones sanguÃneas, antecedente de tatuajes o uso de drogas endovenosas. Solo una de las 4 VHC positivas tuvo serologÃa positiva para sÃfilis co-existentemente y ninguna para VIH. Una de las 200 TS enroladas tuvo infección por VIH.Â
Conclusiones: la seroprevalencia de anticuerpos contra el VHC en TS es mayor que la reportada en poblaciones similares en otras ciudades del Perú. Esta población se caracterizó por tener una conducta sexual de alto riesgo y no tener antecedentes de transfusión sanguÃnea ni consumo de droga endovenosa
Autoimmune congenital heart block and primary Sjogren's syndrome:characterisation and outcomes of 49 cases
Objective. To characterise autoimmune congenital heart block (CHB) associated with a maternal diagnosis of primary Sjogren's syndrome (pSS) confirmed either before, concomitant or after the first pregnancy complicated with CHB. Methods. The following inclusion criteria were applied: (i) Mothers with positive Ro/La autoantibodies detected previously or at the time of diagnosis of the first case of CHB; (ii) diagnosis of CHB confirmed by fetal echocardiography; (iii) AV block diagnosed in uterus, at birth or within the neonatal period (0-27 days after birth) (8); (iv) absence of anatomical cardiac abnormalities which might be causal of AV block; and (v) maternal fulfillment of the 2002 SS criteria before, during or after having a pregnancy complicated with CHB. Results. We identified 49 cases of autoimmune CHB in children born from 44 mothers who had a mean age at the time of pregnancy of 30.3 years (range 18 to 41). At the time of diagnosis of autoimmune CHB, all mothers had positive anti-Ro antibodies and 28/ 44 (64%) were positive for anti-La antibodies. Only 10 (22%) mothers with affected pregnancies had a diagnosis of primary SS at the time of diagnosis of the first pregnancy complicated by CHB (a mean of 4 years before, ranging from 1 to 10 years). In 6 (14%) mothers, primary SS was diagnosed during pregnancy or less than 12 months after the delivery/termination. In the remaining 28 ( 64%) mothers, pSS was confirmed 1-5 years after CHB diagnosis (n=19, 68%), 6-10 years after (n= 2, 7%), or more than 10 years after the first case of CHB was diagnosed (n=7, 25%). CHB was diagnosed in uterus in all cases but two. AV block was initially incomplete in 11 fetuses and complete in 36 (no available data in 2 cases). Among the 35 (71%) surviving children with CHB, 5 (14%) developed other features of neonatal lupus. After the index pregnancy, 12 women had 20 subsequent pregnancies: five were complicated by a CHB ( recurrence rate of CHB of 25%). The 4 women who had recurrent CHB were double-positive for anti-Ro and anti-La antibodies, and all had a confirmed pSS before having the first index case of CHB. Conclusion. In pSS, autoimmune CHB could be one of the first "indirect" signs of the disease in women of childbearing-age, in whom the diagnosis is confirmed several years later. Some maternal characteristics could be related with recurrent CHB, such as having an already-confirmed diagnosis of pSS and carrying the two Ro/La autoantibodies
Autoimmune congenital heart block and primary Sjogren's syndrome:characterisation and outcomes of 49 cases
Objective. To characterise autoimmune congenital heart block (CHB) associated with a maternal diagnosis of primary Sjogren's syndrome (pSS) confirmed either before, concomitant or after the first pregnancy complicated with CHB. Methods. The following inclusion criteria were applied: (i) Mothers with positive Ro/La autoantibodies detected previously or at the time of diagnosis of the first case of CHB; (ii) diagnosis of CHB confirmed by fetal echocardiography; (iii) AV block diagnosed in uterus, at birth or within the neonatal period (0-27 days after birth) (8); (iv) absence of anatomical cardiac abnormalities which might be causal of AV block; and (v) maternal fulfillment of the 2002 SS criteria before, during or after having a pregnancy complicated with CHB. Results. We identified 49 cases of autoimmune CHB in children born from 44 mothers who had a mean age at the time of pregnancy of 30.3 years (range 18 to 41). At the time of diagnosis of autoimmune CHB, all mothers had positive anti-Ro antibodies and 28/ 44 (64%) were positive for anti-La antibodies. Only 10 (22%) mothers with affected pregnancies had a diagnosis of primary SS at the time of diagnosis of the first pregnancy complicated by CHB (a mean of 4 years before, ranging from 1 to 10 years). In 6 (14%) mothers, primary SS was diagnosed during pregnancy or less than 12 months after the delivery/termination. In the remaining 28 ( 64%) mothers, pSS was confirmed 1-5 years after CHB diagnosis (n=19, 68%), 6-10 years after (n= 2, 7%), or more than 10 years after the first case of CHB was diagnosed (n=7, 25%). CHB was diagnosed in uterus in all cases but two. AV block was initially incomplete in 11 fetuses and complete in 36 (no available data in 2 cases). Among the 35 (71%) surviving children with CHB, 5 (14%) developed other features of neonatal lupus. After the index pregnancy, 12 women had 20 subsequent pregnancies: five were complicated by a CHB ( recurrence rate of CHB of 25%). The 4 women who had recurrent CHB were double-positive for anti-Ro and anti-La antibodies, and all had a confirmed pSS before having the first index case of CHB. Conclusion. In pSS, autoimmune CHB could be one of the first "indirect" signs of the disease in women of childbearing-age, in whom the diagnosis is confirmed several years later. Some maternal characteristics could be related with recurrent CHB, such as having an already-confirmed diagnosis of pSS and carrying the two Ro/La autoantibodies
Single domain antibody multimers confer protection against rabies infection
Post-exposure prophylactic (PEP) neutralizing antibodies against Rabies are the most effective way to prevent infection-related fatality. The outer envelope glycoprotein of the Rabies virus (RABV) is the most significant surface antigen for generating virus-neutralizing antibodies. The small size and uncompromised functional specificity of single domain antibodies (sdAbs) can be exploited in the fields of experimental therapeutic applications for infectious diseases through formatting flexibilities to increase their avidity towards target antigens. In this study, we used phage display technique to select and identify sdAbs that were specific for the RABV glycoprotein from a naïve llama-derived antibody library. To increase their neutralizing potencies, the sdAbs were fused with a coiled-coil peptide derived from the human cartilage oligomeric matrix protein (COMP48) to form homogenous pentavalent multimers, known as combodies. Compared to monovalent sdAbs, the combodies, namely 26424 and 26434, exhibited high avidity and were able to neutralize 85-fold higher input of RABV (CVS-11 strain) pseudotypes in vitro, as a result of multimerization, while retaining their specificities for target antigen. 26424 and 26434 were capable of neutralizing CVS-11 pseudotypes in vitro by 90–95% as compared to human rabies immunoglobulin (HRIG), currently used for PEP in Rabies. The multimeric sdAbs were also demonstrated to be partially protective for mice that were infected with lethal doses of rabies virus in vivo. The results demonstrate that the combodies could be valuable tools in understanding viral mechanisms, diagnosis and possible anti-viral candidate for RABV infection
Neutrophils in cancer: neutral no more
Neutrophils are indispensable antagonists of microbial infection and facilitators of wound healing. In the cancer setting, a newfound appreciation for neutrophils has come into view. The traditionally held belief that neutrophils are inert bystanders is being challenged by the recent literature. Emerging evidence indicates that tumours manipulate neutrophils, sometimes early in their differentiation process, to create diverse phenotypic and functional polarization states able to alter tumour behaviour. In this Review, we discuss the involvement of neutrophils in cancer initiation and progression, and their potential as clinical biomarkers and therapeutic targets
Systemic manifestations of primary Sjögren's syndrome out of the ESSDAI classification: prevalence and clinical relevance in a large international, multi-ethnic cohort of patients
OBJECTIVES:
To analyse the frequency and characterise the systemic presentation of primary Sjögren’s syndrome (SS) out of the ESSDAI classification in a large international, multi-ethnic cohort of patients.
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METHODS:
The Big Data Sjögren Project Consortium is an international, multicentre registry based on world-wide data-sharing and cooperative merging of pre-existing clinical SS databases from leading centres in clinical research in SS from the five continents. A list of 26 organ-by-organ systemic features not currently included in the ESSDAI classification was defined according to previous studies; these features were retrospectively recorded.
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RESULTS:
Information about non-ESSDAI features was available in 6331 patients [5,917 female, mean age at diagnosis 52 years, mainly White (86.3%)]. A total of 1641 (26%) patients had at least one of the ESSDAI systemic features. Cardiovascular manifestations were the most frequent organ-specific group of non-ESSDAI features reported in our patients (17% of the total cohort), with Raynaud’s phenomenon being reported in 15%. Patients with systemic disease due to non-ESSDAI features had a lower frequency of dry mouth (90.7% vs. 94.1%, p<0.001) and positive minor salivary gland biopsy (86.7% vs. 89%, p=0.033), a higher frequency of anti-Ro/SSA (74.7% vs. 68.7%, p<0.001), anti-La/SSB antibodies (44.5% vs. 40.4%, p=0.004), ANA (82.7% vs. 79.5%, p=0.006), low C3 levels (17.4% vs. 9.7%, p<0.001), low C4 levels (14.4% vs. 9.6%, p<0.001), and positive serum cryoglobulins (8.6% vs. 5.5%, p=0.001). Systemic activity measured by the ESSDAI, clinESSDAI and DAS was higher in patients with systemic disease out of the ESSDAI in comparison with those without these features (p<0.001 for all comparisons).
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CONCLUSIONS:
More than a quarter of patients with primary SS may have systemic manifestations not currently included in the ESSDAI classification, with a wide variety of cardiovascular, digestive, pulmonary, neurological, ocular, ENT (ear, nose, and throat), cutaneous and urological features that increase the scope of the systemic phenotype of the disease. However, the individual frequency of each of these non-ESSDAI features was very low, except for Raynaud’s phenomenon
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