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BACKGROUND: Von Hippel-Lindau (VHL) disease is a rare autosomal dominant disorder that predisposes patients to develop multiple cysts and tumors, such as hemangioblastomas (HBs) and clear cell renal cell carcinoma (ccRCC), due to mutations in the VHL tumor suppressor gene. While treatment of HBs varies based on their characteristics and has improved patient survival, it still involves high morbidity and mortality, leading to ongoing debates and studies to refine therapy strategies. Recent developments include the emergence of Belzutifan, a novel inhibitor targeting hypoxia-inducible factor 2α (HIF-2α), which has shown promising results in ongoing trials, particularly for patients not immediately requiring surgery. METHODS: This systematic review and meta-analysis aimed to comprehensively evaluate the efficacy and safety of Belzutifan for treating HBs associated with VHL disease. Search was conducted across Medline, Embase, Cochrane, and Web of Science databases. Statistical Analysis was performed, with proportions and 95 % confidence intervals. Statistical analyses were carried out using R Studio. RESULTS: Ten studies were selected, comprising 553 patients. The population mean age was 40 (24-65), and 50 % of the population was formed by males. In terms of proportion, 6 analyses were performed: Disease Stability of 31 % [95 %CI:14 %-47 %; I2 = 2 %]; Disease Progression of 2 %[95 %CI:0 %-9 %; I2 = 0 %]; Partial Response of 75 % [95 %CI:54 %-96 %; I2 = 58 %]. Complete response of 1 % [95 %CI:0 %-7 %; I2 = 0 %];and Side effects, anemia 81 % rate [95 % CI:54 %-100 %; I2 = 94 %], and fatigue rate of 79 % [95 % CI:54 %-100 %;I2 = 94 %]. CONCLUSION: Results indicate that Belzutifan effectively stabilizes disease, reduces tumor progression, and achieves significant therapeutic responses, although side effects like anemia and fatigue were noted.
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Currently, coffee fermentation is visually operated, which results in incomplete or excessive processes and coffees with undesirable characteristics. In front of it, pH and total soluble solids (TSS) have been shown to be good fermentation indicators, although this requires rapid, accurate, and chemical-free measurement techniques such as NIR spectroscopy. However, the complexity of the NIR spectra requires optimization steps in which variable selection techniques simplify profiles and subsequent models. This work tests a new covering array feature selection (CAFS) approach on NIR spectra to optimize prediction models in coffee samples during fermentation. Spectral profiles in the range 1100-2100 nm were extracted from coffee beans (Typica, Caturra, and Catimor varieties) raw and during fermentation (4, 8, 12, 16, 20, and 24 h). Partial least-squares regressions (PLSR) were performed using full spectra using a five-fold cross-validation strategy for training and validation. The relevant wavelengths were then selected using the ß coefficients, the important projection of variables (VIP), and the CAFS method. Finally, optimized models were performed using the relevant wavelengths and compared among these using their statistical metrics. The models performed using the selected variables (22-47) of CAFS showed the best performance in predicting pH (R 2 = 0.825-0.903, RMSE = 0.096-0.158, RPD = 6.33-10.38) and TSS (R 2 = 0.865-0.922, RMSE = 0.688-1.059, RPD = 0.94-1.45) compared to the other methods. These findings suggest that simple and efficient models could be performed and implemented in routine analysis due to the maximum coverage and minimum cardinality of CAFS.
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To date, no immunotherapy approaches have managed to fully overcome T-cell exhaustion, which remains a mandatory fate for chronically activated effector cells and a major therapeutic challenge. Understanding how to reprogram CD8+ tumor-infiltrating lymphocytes away from exhausted effector states remains an elusive goal. Our work provides evidence that orthogonal gene engineering of T cells to secrete an interleukin (IL)-2 variant binding the IL-2Rßγ receptor and the alarmin IL-33 reprogrammed adoptively transferred T cells to acquire a novel, synthetic effector state, which deviated from canonical exhaustion and displayed superior effector functions. These cells successfully overcame homeostatic barriers in the host and led-in the absence of lymphodepletion or exogenous cytokine support-to high levels of engraftment and tumor regression. Our work unlocks a new opportunity of rationally engineering synthetic CD8+ T-cell states endowed with the ability to avoid exhaustion and control advanced solid tumors.
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Linfocitos T CD8-positivos , Inmunoterapia Adoptiva , Interleucina-2 , Neoplasias Experimentales , Linfocitos T CD8-positivos/inmunología , Agotamiento de Células T , Linfocitos Infiltrantes de Tumor/inmunología , Interleucina-2/farmacología , Interleucina-33 , Ingeniería de Proteínas , Femenino , Animales , Ratones , Ratones Endogámicos C57BL , Línea Celular Tumoral , Neoplasias Experimentales/terapia , Receptor de Muerte Celular Programada 1/metabolismoRESUMEN
Ly108 (SLAMF6) is a homophilic cell surface molecule that binds SLAM-associated protein (SAP), an intracellular adapter protein that modulates humoral immune responses. Furthermore, Ly108 is crucial for the development of natural killer T (NKT) cells and CTL cytotoxicity. Significant attention has been paid towards expression and function of Ly108 since multiple isoforms were identified, i.e., Ly108-1, Ly108-2, Ly108-3, and Ly108-H1, some of which are differentially expressed in several mouse strains. Surprisingly, Ly108-H1 appeared to protect against disease in a congenic mouse model of Lupus. Here, we use cell lines to further define Ly108-H1 function in comparison with other isoforms. We show that Ly108-H1 inhibits IL-2 production while having little effect upon cell death. With a refined method, we could detect phosphorylation of Ly108-H1 and show that SAP binding is retained. We propose that Ly108-H1 may regulate signaling at two levels by retaining the capability to bind its extracellular as well as intracellular ligands, possibly inhibiting downstream pathways. In addition, we detected Ly108-3 in primary cells and show that this isoform is also differentially expressed between mouse strains. The presence of additional binding motifs and a non-synonymous SNP in Ly108-3 further extends the diversity between murine strains. This work highlights the importance of isoform awareness, as inherent homology can present a challenge when interpreting mRNA and protein expression data, especially as alternatively splicing potentially affects function.
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Antígenos Ly , Transducción de Señal , Animales , Ratones , Antígenos Ly/genética , Línea Celular , Fosforilación , Isoformas de Proteínas/genéticaRESUMEN
The rising interest in quinoa (Chenopodium quinoa Willd.) is due to its high protein content and gluten-free condition; nonetheless, the presence of foreign bodies in quinoa processing facilities is an issue that must be addressed. As a result, convolutional neural networks have been adopted, mostly because of their data extraction capabilities, which had not been utilized before for this purpose. Consequently, the main objective of this work is to evaluate convolutional neural networks with a learning transfer for foreign bodies identification in quinoa samples. For experimentation, quinoa samples were collected and manually split into 17 classes: quinoa grains and 16 foreign bodies. Then, one thousand images were obtained from each class in RGB space and transformed into four different color spaces (L*a*b*, HSV, YCbCr, and Gray). Three convolutional neural networks (AlexNet, MobileNetv2, and DenseNet-201) were trained using the five color spaces, and the evaluation results were expressed in terms of accuracy and F-score. All the CNN approaches compared showed an F-score ranging from 98% to 99%; both color space and CNN structure were found to have significant effects on the F-score. Also, DenseNet-201 was the most robust architecture and, at the same time, the most time-consuming. These results evidence the capacity of CNN architectures to be used for the discrimination of foreign bodies in quinoa processing facilities.
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Chenopodium quinoa , Chenopodium quinoa/química , Redes Neurales de la Computación , Semillas/química , Dieta Sin Gluten , Aprendizaje AutomáticoRESUMEN
Near-Infrared Spectroscopy (NIRS) has shown to be helpful in the study of rice, tea, cocoa, and other foods due to its versatility and reduced sample treatment. However, the high complexity of the data produced by NIR sensors makes necessary pre-treatments such as feature selection techniques that produce compact profiles. Supervised and unsupervised techniques have been tested, creating different subsets of features for classification, which affect the performance of the classifiers based on such compact profiles. In this sense, we propose and test a new covering array feature selection (CAFS) algorithm coupled to the naïve Bayes classifier (NBC) to discriminate among Amazonian cacao nibs from six cacao clones. The CAFS wrapper approach looks for the wavebands that maximize the F1-score, and then, are more relevant for classification. For this purpose, cacao pods of six varieties were collected, and their grains were extracted and processed (fermented, dried, roasted, and milled) to obtain cacao nibs. Then from each clone NIR spectral profiles in the range of 1100-2500 nm were extracted, and relevant wavebands were selected using the proposed CAFS algorithm. For comparison, two standard feature selection techniques were implemented the multi-cluster feature selection MCFS and the eigenvector centrality feature selection ECFS. Then, based on the different selected variables, three NBCs were built and compared among them through statistical metrics. The results showed that using the wavebands selected by CAFS, the NBC performed an average accuracy of 99.63%; being this superior to the 94.92% and 95.79% for ECFS and MCFS respectively. These results showed that the wavebands selected by the proposed CAFS algorithm allowed obtaining a better fit concerning other feature selection methods reported in the literature.
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Cacao , Algoritmos , Teorema de Bayes , Células Clonales , Espectroscopía Infrarroja CortaRESUMEN
The mechanisms regulating exhaustion of tumor-infiltrating lymphocytes (TIL) and responsiveness to PD-1 blockade remain partly unknown. In human ovarian cancer, we show that tumor-specific CD8+ TIL accumulate in tumor islets, where they engage antigen and upregulate PD-1, which restrains their functions. Intraepithelial PD-1+CD8+ TIL can be, however, polyfunctional. PD-1+ TIL indeed exhibit a continuum of exhaustion states, with variable levels of CD28 costimulation, which is provided by antigen-presenting cells (APC) in intraepithelial tumor myeloid niches. CD28 costimulation is associated with improved effector fitness of exhausted CD8+ TIL and is required for their activation upon PD-1 blockade, which also requires tumor myeloid APC. Exhausted TIL lacking proper CD28 costimulation in situ fail to respond to PD-1 blockade, and their response may be rescued by local CTLA-4 blockade and tumor APC stimulation via CD40L.
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Células Presentadoras de Antígenos/metabolismo , Antígenos CD28/metabolismo , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Células Mieloides/metabolismo , Neoplasias/tratamiento farmacológico , Nicho de Células Madre/genética , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias/inmunologíaRESUMEN
Food packaging materials are commonly derived from petroleum that increases global contamination; this raises the interest to evaluate raw material from renewable sources such as whey protein for the development of packaging materials, especially to produce active films. This research aimed to evaluate whey protein-based film properties when natamycin, nanoemulsioned α-tocopherol, or both were added. An oil-in-water (O/W) nanoemulsion of antioxidant (α-tocopherol) was prepared by microfluidization technique. Four films were prepared with different levels of natamycin and nanoemulsified α-tocopherol and were characterized in terms of physicochemical, mechanical, optical-properties, water vapor barrier, FTIR, microstructure, antioxidant and antimicrobial activity. The natamycin, nanoemulsified α-tocopherol, or both did not modify the moisture content of the films. Moreover lead to a significant reduction of tensile strength and elastic modulus, while presenting growth in the elongation at break. Film opacity, the total color difference, the UV-Vis light barrier, and the water vapor permeability values increased when compounds were incorporated into the film. The microstructure studies showed uniformly distributed porosity throughout the films. The addition of nanoemulsioned α-tocopherol into whey protein-based films provoked antioxidant activity and the addition of natamycin produced films with effectivity against C. albicans, P. chrysogenum, and S. cerevisiae, allowing develop a material appropriate for use as active food packaging.
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This work evaluates near-infrared (NIR) spectroscopy coupled with chemometric tools for determining the superficial content of citral ( S C C t ) on microparticles. To perform this evaluation, using spray drying, citral was encapsulated in a matrix of dextrin using twelve combinations of citral:dextrin ratios (CDR) and inlet air temperatures (IAT). From each treatment, six samples were extracted, and their S C C t and NIR absorption spectral profiles were measured. Then, the spectral profiles, pretreated and randomly divided into modeling and validation datasets, were used to build the following prediction models: principal component analysis-multilinear regression (PCA-MLR), principal component analysis-artificial neural network (PCA-ANN), partial least squares regression (PLSR) and an artificial neural network (ANN). During the validation stage, the models showed R 2 values from 0.73 to 0.96 and a root mean squared error (RMSE) range of [0.061-0.140]. Moreover, when the models were compared, the full and optimized ANN models showed the best fits. According to this study, NIR coupled with chemometric tools has the potential for application in determining S C C t on microparticles, particularly when using ANN models.
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Regulatory factor X 7 (Rfx7) is an uncharacterized transcription factor belonging to a family involved in ciliogenesis and immunity. Here, we found that deletion of Rfx7 leads to a decrease in natural killer (NK) cell maintenance and immunity in vivo. Genomic approaches showed that Rfx7 coordinated a transcriptional network controlling cell metabolism. Rfx7-/- NK lymphocytes presented increased size, granularity, proliferation, and energetic state, whereas genetic reduction of mTOR activity mitigated those defects. Notably, Rfx7-deficient NK lymphocytes were rescued by interleukin 15 through engagement of the Janus kinase (Jak) pathway, thus revealing the importance of this signaling for maintenance of such spontaneously activated NK cells. Rfx7 therefore emerges as a novel transcriptional regulator of NK cell homeostasis and metabolic quiescence.
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Interleucina-15/metabolismo , Células Asesinas Naturales/metabolismo , Factor Regulador X1/metabolismo , Animales , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Quimera , Metabolismo Energético , Redes Reguladoras de Genes , Inmunidad Celular/genética , Inmunidad Innata/genética , Quinasas Janus/metabolismo , Células Asesinas Naturales/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor Regulador X1/genética , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
The objective of this research was to develop a methodology for optimizing multilayer-perceptron-type neural networks by evaluating the effects of three neural architecture parameters, namely, number of hidden layers (HL), neurons per hidden layer (NHL), and activation function type (AF), on the sum of squares error (SSE). The data for the study were obtained from quality parameters (physicochemical and microbiological) of milk samples. Architectures or combinations were organized in groups (G1, G2, and G3) generated upon interspersing one, two, and three layers. Within each group, the networks had three neurons in the input layer, six neurons in the output layer, three to twenty-seven NHL, and three AF (tan-sig, log-sig, and linear) types. The number of architectures was determined using three factorial-type experimental designs, which reached 63, 2 187, and 50 049 combinations for G1, G2 and G3, respectively. Using MATLAB 2015a, a logical sequence was designed and implemented for constructing, training, and evaluating multilayer-perceptron-type neural networks using parallel computing techniques. The results show that HL and NHL have a statistically relevant effect on SSE, and from two hidden layers, AF also has a significant effect; thus, both AF and NHL can be evaluated to determine the optimal combination per group. Moreover, in the three study groups, it is observed that there is an inverse relationship between the number of processors and the total optimization time.
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Modelos Neurológicos , Redes Neurales de la Computación , Algoritmos , Animales , Bovinos , Computadores , LecheRESUMEN
Objetivo Establecer la prevalencia de la patología maligna en pacientes con masa sólida palpable, sin diagnóstico previo de cáncer de seno en dos hospitales de Bogotá, Colombia. Materiales y métodos Estudio descriptivo retrospectivo entre marzo de 2010 y febrero de 2013 en los hospitales de San José e Infantil Universitario de San José, Bogotá D. C., Colombia. Se incluyeron mujeres mayores de 14 años que consultaron por masa sólida palpable sin diagnóstico previo de cáncer de seno, corroborada por examen físico; no se consideró ningún criterio de exclusión. Los datos se recolectaron de las historias clínicas y se llevaron a un formato creado por los investigadores. El programa estadístico utilizado fue Stata 13. Resultados Se confirmó la masa en 342 pacientes por examen clínico, en 307 pacientes con resultado de biopsia. La prevalencia de la patología maligna fue 12,2% y benigna 71,66%. Discusión La prevalencia de patología maligna por masa palpable fue menor que los datos reportados a nivel mundial, siendo el tumor más frecuente el carcinoma ductal infiltrante en un 87%, carcinoma lobulillar infiltrante en 6,4%), con estadio clínico IIA y BI-RADS 4 A (ecografía) y BI-RADS 4B (mamografía).
Objective To determine the prevalence rate of malignancy in patients with no prior breast cancer diagnosis who consulted for a solid palpable mass in two hospitals in Bogotá, Colombia. Materials and methods A descriptive retrospective study conducted between March 2010 and February 2013 at San José and Infantil Universitario de San José hospitals in Bogotá D. C., Colombia. Women 14 years or older with no prior breast cancer diagnosis who consulted for a palpable solid mass, confirmed by physical exam, were included. No exclusion criteria were considered. Data was collected from the clinical records and included in a format created by the researchers. Stata 13 was used for data analysis. Results The mass was confirmed by physical exam in 342 patients and by a biopsy in 307 patients. The prevalence rate for malignancy was 12.2% and for benign masses 71.66%. Discussion Our prevalence of breast cancer associated with a palpable mass was less than worldwide reported prevalence. The most frequent malignancy was invasive ductal carcinoma in 87% and invasive lobular carcinoma in 6.4% in stage IIA and BI-RADS 4A ultrasound category and BI-RADS 4B mammogram category.
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Humanos , Femenino , Adolescente , Adulto , Neoplasias de la Mama , Prevalencia , Mamografía , Carcinoma Ductal de Mama , MastodiniaRESUMEN
NLRC5 is a transcriptional regulator of MHC class I (MHCI), which maintains high MHCI expression particularly in T cells. Recent evidence highlights an important NK-T-cell crosstalk, raising the question on whether NLRC5 specifically modulates this interaction. Here we show that NK cells from Nlrc5-deficient mice exhibit moderate alterations in inhibitory receptor expression and responsiveness. Interestingly, NLRC5 expression in T cells is required to protect them from NK-cell-mediated elimination upon inflammation. Using T-cell-specific Nlrc5-deficient mice, we show that NK cells surprisingly break tolerance even towards 'self' Nlrc5-deficient T cells under inflammatory conditions. Furthermore, during chronic LCMV infection, the total CD8(+) T-cell population is severely decreased in these mice, a phenotype reverted by NK-cell depletion. These findings strongly suggest that endogenous T cells with low MHCI expression become NK-cell targets, having thus important implications for T-cell responses in naturally or therapeutically induced inflammatory conditions.
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Antígenos de Histocompatibilidad Clase I/inmunología , Péptidos y Proteínas de Señalización Intracelular/inmunología , Células Asesinas Naturales/inmunología , Autotolerancia/inmunología , Linfocitos T/inmunología , Animales , Animales Congénicos , Infecciones por Arenaviridae/inmunología , Chlorocebus aethiops , Citometría de Flujo , Regulación de la Expresión Génica/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Inflamación/inducido químicamente , Inflamación/inmunología , Inductores de Interferón/toxicidad , Péptidos y Proteínas de Señalización Intracelular/genética , Virus de la Coriomeningitis Linfocítica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Poli I-C/toxicidad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Bazo/citología , Bazo/inmunología , Linfocitos T/efectos de los fármacos , Células VeroRESUMEN
Nucleotide-binding domain and leucine-rich repeat containing receptors (NLRs) are intracellular proteins mainly involved in pathogen recognition, inflammatory responses, and cell death. Until recently, the function of the family member NLR caspase recruitment domain (CARD) containing 5 (NLRC5) has been a matter of debate. It is now clear that NLRC5 acts as a transcriptional regulator of the major-histocompatibility complex class I. In this review we detail the development of our understanding of NLRC5 function, discussing both the accepted and the controversial aspects of NLRC5 activity. We give insight into the molecular mechanisms, and the potential implications, of NLRC5 function in health and disease.
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Mutations affecting the SLAM-associated protein (SAP) are responsible for the X-linked lympho-proliferative syndrome (XLP), a severe primary immunodeficiency syndrome with disease manifestations that include fatal mononucleosis, B cell lymphoma and dysgammaglobulinemia. It is well accepted that insufficient help by SAP-/- CD4+ T cells, in particular during the germinal center reaction, is a component of dysgammaglobulinemia in XLP patients and SAP-/- animals. It is however not well understood whether in XLP patients and SAP-/- mice B cell functions are affected, even though B cells themselves do not express SAP. Here we report that B cell intrinsic responses to haptenated protein antigens are impaired in SAP-/- mice and in Rag-/- mice into which B cells derived from SAP-/- mice together with wt CD4+ T cells had been transferred. This impaired B cells functions are in part depending on the genetic background of the SAP-/- mouse, which affects B cell homeostasis. Surprisingly, stimulation with an agonistic anti-CD40 causes strong in vivo and in vitro B cell responses in SAP-/- mice. Taken together, the data demonstrate that genetic factors play an important role in the SAP-related B cell functions. The finding that anti-CD40 can in part restore impaired B cell responses in SAP-/- mice, suggests potentially novel therapeutic interventions in subsets of XLP patients.
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Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Péptidos y Proteínas de Señalización Intracelular/genética , Trastornos Linfoproliferativos/genética , Trastornos Linfoproliferativos/inmunología , Animales , Linfocitos B/citología , Linfocitos T CD4-Positivos/trasplante , Antígenos CD40/inmunología , Antígenos CD40/metabolismo , Proteínas de Homeodominio/genética , Leucosialina/metabolismo , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Asociada a la Molécula de Señalización de la Activación LinfocitariaRESUMEN
The costimulatory receptor Slamf6 partially controls lupus-related autoimmunity in congenic Sle1b mice; for instance, the presence of the protein isoform Slamf6-H1 in Sle1b.Slamf6-H1 mice mitigates disease. Here, we report that young Sle1b mice, but not Sle1b.Slamf6-H1 or B6 mice, contain a memory T-helper cell subset identified by ]mt]2-fold increase in expression of 17 genes, chief among which is Spp1, encoding the cytokine osteopontin (OPN). These T follicular helper (TFH) cells, including OPN(+) TFH cells, expand concomitantly with severity of the disease. By contrast, Sle1b.Slamf6-H1 or Sle1b.SAP(-)/(-) mice do not develop autoantibodies and the number of T(FH) cells is 5 times lower than in age-matched Sle1b mice. By comparing Sle1b and Sle1b.OPN(-)/(-) mice, we find that the lack of OPN expression impedes early autoantibody production. Furthermore, on the adoptive transfer of Sle1b.OPN(-)/(-) CD4(+) T cells into bm12 recipients autoantibody production and germinal center formation is reduced compared to recipients of Sle1b.OPN(+/+) CD4(+) T cells. We propose a model in which OPN provides a survival signal for a precursor T(FH) cell subset, which is a key factor in autoimmunity.
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Antígenos CD/inmunología , Autoinmunidad/inmunología , Osteopontina/inmunología , Receptores de Superficie Celular/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciación/genética , Antígenos de Diferenciación/inmunología , Antígenos de Diferenciación/metabolismo , Autoinmunidad/genética , Western Blotting , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Proliferación Celular , Femenino , Citometría de Flujo , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Masculino , Ratones , Ratones Noqueados , Osteopontina/genética , Osteopontina/metabolismo , Receptor de Muerte Celular Programada 1 , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Isoformas de Proteínas/metabolismo , Receptores CXCR5/genética , Receptores CXCR5/inmunología , Receptores CXCR5/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/metabolismo , Transcriptoma/inmunologíaRESUMEN
One of the manifestations of X-linked lymphoproliferative disease (XLP) is progressive agammaglobulinemia, caused by the absence of a functional signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) in T, invariant natural killer T (NKT) cells and NK cells. Here we report that α-galactosylceramide (αGalCer) activated NKT cells positively regulate antibody responses to haptenated protein antigens at multiple checkpoints, including germinal center formation and affinity maturation. Whereas NKT cell-dependent B cell responses were absent in SAP(-/-).B6 mice that completely lack NKT cells, the small number of SAP-deficient NKT cells in SAP(-/-).BALB/c mice adjuvated antibody production, but not the germinal center reaction. To test the hypothesis that SAP-deficient NKT cells can facilitate humoral immunity, SAP was deleted after development in SAP(fl/fl).tgCreERT2.B6 mice. We find that NKT cell intrinsic expression of SAP is dispensable for noncognate helper functions, but is critical for providing cognate help to antigen-specific B cells. These results demonstrate that SLAM-family receptor-regulated cell-cell interactions are not limited to T-B cell conjugates. We conclude that in the absence of SAP, several routes of NKT cell-mediated antibody production are still accessible. The latter suggests that residual NKT cells in XLP patients might contribute to variations in dysgammaglobulinemia.
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Linfocitos B/inmunología , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/inmunología , Células Asesinas Naturales/inmunología , Trastornos Linfoproliferativos/inmunología , Animales , Antineoplásicos Hormonales/farmacología , Linfocitos B/citología , Comunicación Celular/efectos de los fármacos , Comunicación Celular/inmunología , Femenino , Galactosilceramidas/metabolismo , Galactosilceramidas/farmacología , Expresión Génica/inmunología , Centro Germinal/inmunología , Haptenos/inmunología , Haptenos/metabolismo , Células Asesinas Naturales/citología , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Tamoxifeno/farmacologíaRESUMEN
Studies of human systemic lupus erythematosus patients and of murine congenic mouse strains associate genes in a DNA segment on chromosome 1 with a genetic predisposition for this disease. The systematic analysis of lupus-prone congenic mouse strains suggests a role for two isoforms of the Ly108 receptor in the pathogenesis of the disease. In this study, we demonstrate that Ly108 is involved in the pathogenesis of lupus-related autoimmunity in mice. More importantly, we identified a third protein isoform, Ly108-H1, which is absent in two lupus-prone congenic animals. Introduction of an Ly108-H1-expressing transgene markedly diminishes T cell-dependent autoimmunity in congenic B6.Sle1b mice. Thus, an immune response-suppressing isoform of Ly108 can regulate the pathogenesis of lupus.
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Antígenos Ly/genética , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/prevención & control , Animales , Autoinmunidad , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Exones , Femenino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Isoformas de Proteínas/genéticaRESUMEN
Several genes in an interval of human and mouse chromosome 1 are associated with a predisposition for systemic lupus erythematosus. Congenic mouse strains that contain a 129-derived genomic segment, which is embedded in the B6 genome, develop lupus because of epistatic interactions between the 129-derived and B6 genes, e.g. in B6.129chr1b mice. If a gene that is located on chromosome 1 is altered through homologous recombination in 129-derived embryonic stem cells (ES cells) and if the resultant knockout mouse is backcrossed with B6, interpretation of the phenotype of the mutant mouse may be affected by epistatic interactions between the 129 and B6 genomes. Here, we report that knockout mice of two adjacent chromosome 1 genes, Slamf1(-/-) and Slamf2(-/-), which were generated with the same 129-derived ES cell line, develop features of lupus, if backcrossed on to the B6 genetic background. By contrast, Slamf1(-/-) [BALB/c.129] and Slamf2(-/-) [BALB/c.129] do not develop disease. Surprisingly, Slamf1(-/-) [B6.129] mice develop both auto-antibodies and glomerulonephritis between 3 and 6 months of age, while disease fully develops in Slamf1(-/-) [B6.129] mice after 9-14 months. Functional analyses of CD4(+) T cells reveals that Slamf2(-/-) T cells are resistant to tolerance induction in vivo. We conclude that the Slamf2(-/-) mutation may have a unique influence on T-cell tolerance and lupus.
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Antígenos CD/genética , Antígenos CD/inmunología , Autoanticuerpos/inmunología , Glomerulonefritis/inmunología , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunología , Animales , Glomerulonefritis/genética , Humanos , Inmunohistoquímica , Endogamia , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/inmunología , Ratones , Ratones de la Cepa 129 , Ratones Congénicos , Ratones Noqueados , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación LinfocitariaRESUMEN
EWS/FLI1-activated transcript 2 (EAT-2)A and EAT-2B are single SH2-domain proteins, which bind to phosphorylated tyrosines of signaling lymphocyte activation molecule family receptors in murine NK cells. While EAT-2 is a positive regulator in human cells, a negative regulatory role was attributed to the adapter in NK cells derived from EAT-2A-deficient 129Sv mice. To evaluate whether the genetic background or the presence of a selection marker in the mutant mice could influence the regulatory mode of these adapters, we generated EAT-2A-, EAT-2B-, and EAT-2A/B-deficient mice using C57BL/6 embryonic stem cells. We found that NK cells from EAT-2A- and EAT-2A/B-deficient mice were unable to kill tumor cells in a CD244- or CD84-dependent manner. Furthermore, EAT-2A/B positively regulate phosphorylation of Vav-1, which is known to be implicated in NK cell killing. Thus, as in humans, the EAT-2 adapters act as positive regulators of signaling lymphocyte activation molecule family receptor-specific NK cell functions in C57BL/6 mice.