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Pathogens constantly evolve and can develop mutations that evade host immunity and treatment. Addressing these escape mechanisms requires targeting evolutionarily conserved vulnerabilities, as mutations in these regions often impose fitness costs. We introduce adaptive multi-epitope targeting with enhanced avidity (AMETA), a modular and multivalent nanobody platform that conjugates potent bispecific nanobodies to a human immunoglobulin M (IgM) scaffold. AMETA can display 20+ nanobodies, enabling superior avidity binding to multiple conserved and neutralizing epitopes. By leveraging multi-epitope SARS-CoV-2 nanobodies and structure-guided design, AMETA constructs exponentially enhance antiviral potency, surpassing monomeric nanobodies by over a million-fold. These constructs demonstrate ultrapotent, broad, and durable efficacy against pathogenic sarbecoviruses, including Omicron sublineages, with robust preclinical results. Structural analysis through cryoelectron microscopy and modeling has uncovered multiple antiviral mechanisms within a single construct. At picomolar to nanomolar concentrations, AMETA efficiently induces inter-spike and inter-virus cross-linking, promoting spike post-fusion and striking viral disarmament. AMETA's modularity enables rapid, cost-effective production and adaptation to evolving pathogens.
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Trained immunity, a functional state of myeloid cells, has been proposed as a compelling immune-oncological target. Its efficient induction requires direct engagement of myeloid progenitors in the bone marrow. For this purpose, we developed a bone marrow-avid nanobiologic platform designed specifically to induce trained immunity. We established the potent anti-tumor capabilities of our lead candidate MTP10-HDL in a B16F10 mouse melanoma model. These anti-tumor effects result from trained immunity-induced myelopoiesis caused by epigenetic rewiring of multipotent progenitors in the bone marrow, which overcomes the immunosuppressive tumor microenvironment. Furthermore, MTP10-HDL nanotherapy potentiates checkpoint inhibition in this melanoma model refractory to anti-PD-1 and anti-CTLA-4 therapy. Finally, we determined MTP10-HDL's favorable biodistribution and safety profile in non-human primates. In conclusion, we show that rationally designed nanobiologics can promote trained immunity and elicit a durable anti-tumor response either as a monotherapy or in combination with checkpoint inhibitor drugs.
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Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunidad , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Nanotecnología , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Animales , Conducta Animal , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Proliferación Celular/efectos de los fármacos , Colesterol/metabolismo , Femenino , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Inhibidores de Puntos de Control Inmunológico/farmacología , Inmunidad/efectos de los fármacos , Inmunoterapia , Lipoproteínas HDL/metabolismo , Ratones Endogámicos C57BL , Primates , Distribución Tisular/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacosRESUMEN
DNA methylation at the 5 position of cytosine (5-mC) is a key epigenetic mark that is critical for various biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation (TET) family of DNA hydroxylases. Here, we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma, with diagnostic and prognostic implications. Genome-wide mapping of 5-hmC reveals loss of the 5-hmC landscape in the melanoma epigenome. We show that downregulation of isocitrate dehydrogenase 2 (IDH2) and TET family enzymes is likely one of the mechanisms underlying 5-hmC loss in melanoma. Rebuilding the 5-hmC landscape in melanoma cells by reintroducing active TET2 or IDH2 suppresses melanoma growth and increases tumor-free survival in animal models. Thus, our study reveals a critical function of 5-hmC in melanoma development and directly links the IDH and TET activity-dependent epigenetic pathway to 5-hmC-mediated suppression of melanoma progression, suggesting a new strategy for epigenetic cancer therapy.
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Citosina/análogos & derivados , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Melanoma/genética , Nevo/genética , 5-Metilcitosina/análogos & derivados , Citosina/metabolismo , Proteínas de Unión al ADN/genética , Dioxigenasas , Estudio de Asociación del Genoma Completo , Humanos , Isocitrato Deshidrogenasa/genética , Melanocitos/metabolismo , Melanoma/patología , Nevo/patología , Proteínas Proto-Oncogénicas/genéticaRESUMEN
The peroxisomal disease adrenoleukodystrophy (X-ALD) is caused by loss of the transporter of very-long-chain fatty acids (VLCFAs), ABCD1. An excess of VLCFAs disrupts essential homeostatic functions crucial for axonal maintenance, including redox metabolism, glycolysis and mitochondrial respiration. As mitochondrial function and morphology are intertwined, we set out to investigate the role of mitochondrial dynamics in X-ALD models. Using quantitative 3D transmission electron microscopy, we revealed mitochondrial fragmentation in corticospinal axons in Abcd1- mice. In patient fibroblasts, an excess of VLCFAs triggers mitochondrial fragmentation through the redox-dependent phosphorylation of DRP1 (DRP1S616). The blockade of DRP1-driven fission by the peptide P110 effectively preserved mitochondrial morphology. Furthermore, mRNA inhibition of DRP1 not only prevented mitochondrial fragmentation but also protected axonal health in a Caenorhabditis elegans model of X-ALD, underscoring DRP1 as a potential therapeutic target. Elevated levels of circulating cell-free mtDNA in patients' CSF align this leukodystrophy with primary mitochondrial disorders. Our findings underscore the intricate interplay between peroxisomal dysfunction, mitochondrial dynamics and axonal integrity in X-ALD, shedding light on potential avenues for therapeutic intervention.
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Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP , Adrenoleucodistrofia , Dinaminas , Dinámicas Mitocondriales , Adrenoleucodistrofia/metabolismo , Adrenoleucodistrofia/patología , Adrenoleucodistrofia/genética , Animales , Dinámicas Mitocondriales/fisiología , Humanos , Ratones , Dinaminas/metabolismo , Dinaminas/genética , Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP/genética , Caenorhabditis elegans , Mitocondrias/metabolismo , Mitocondrias/patología , Axones/patología , Axones/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patología , Masculino , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Modelos Animales de Enfermedad , Tractos Piramidales/patología , Tractos Piramidales/metabolismo , Fragmentos de Péptidos , GTP FosfohidrolasasRESUMEN
Quantum dots (QDs) with metal fluoride surface ligands were prepared via reaction with anhydrous oleylammonium fluoride. Carboxylate terminated II-VI QDs underwent carboxylate for fluoride exchange, while InP QDs underwent photochemical acidolysis yielding oleylamine, PH3, and InF3. The final photoluminescence quantum yield (PLQY) reached 83% for InP and near unity for core-shell QDs. Core-only CdS QDs showed dramatic improvements in PLQY, but only after exposure to air. Following etching, the InP QDs were bound by oleylamine ligands that were characterized by the frequency and breadth of the corresponding ν(N-H) bands in the infrared absorption spectrum. The fluoride content (1.6-9.2 nm-2) was measured by titration with chlorotrimethylsilane and compared with the oleylamine content (2.3-5.1 nm-2) supporting the formation of densely covered surfaces. The influence of metal fluoride adsorption on the air stability of QDs is discussed.
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Changes caused by learning that a food is inedible in Aplysia were examined for fast and slow synaptic connections from the buccal ganglia S1 cluster of mechanoafferents to five followers, in response to repeated stimulus trains. Learning affected only fast connections. For these, unique patterns of change were present in each follower, indicating that learning differentially affects the different branches of the mechanoafferents to their followers. In some followers, there were increases in either excitatory or inhibitory connections, and in others, there were decreases. Changes in connectivity resulted from changes in the amplitude of excitation or inhibition, or as a result of the number of connections, or of both. Some followers also exhibited changes in either within or between stimulus train plasticity as a result of learning. In one follower, changes differed from the different areas of the S1 cluster. The patterns of changes in connectivity were consistent with the behavioral changes produced by learning, in that they would produce an increase in the bias to reject or to release food, and a decrease in the likelihood to respond to food.
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Aplysia , Ganglios de Invertebrados , Neuronas Motoras , Aplysia/fisiología , Animales , Neuronas Motoras/fisiología , Ganglios de Invertebrados/fisiología , Aprendizaje/fisiología , Mecanorreceptores/fisiología , Plasticidad Neuronal/fisiología , Alimentos , Conducta Alimentaria/fisiologíaRESUMEN
How does repeated stimulation of mechanoafferents affect feeding motor neurons? Monosynaptic connections from a mechanoafferent population in the Aplysia buccal ganglia to five motor followers with different functions were examined during repeated stimulus trains. The mechanoafferents produced both fast and slow synaptic outputs, which could be excitatory or inhibitory. In contrast, other Aplysia mechanoafferents produce only fast excitation on their followers. In addition, patterns of synaptic connections were different to the different motor followers. Some followers received both fast excitation and fast inhibition, whereas others received exclusively fast excitation. All followers showed strong decreases in fast postsynaptic potential (PSP) amplitude within a stimulus train. Fast and slow synaptic connections were of net opposite signs in some followers but not in others. For one follower, synaptic contacts were not uniform from all subareas of the mechanoafferent cluster. Differences in properties of the buccal ganglia mechanoafferents and other Aplysia mechanoafferents may arise because the buccal ganglia neurons innervate the interior of the feeding apparatus, rather than an external surface, and connect to motor neurons for muscles with different motor functions. Fast connection patterns suggest that these synapses may be activated when food slips, biasing the musculature to release food. The largest slow inhibitory synaptic PSPs may contribute to a delay in the onset of the next behavior. Additional functions are also possible.
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Aplysia , Conducta Alimentaria , Ganglios de Invertebrados , Neuronas Motoras , Animales , Aplysia/fisiología , Neuronas Motoras/fisiología , Ganglios de Invertebrados/fisiología , Conducta Alimentaria/fisiología , Mecanorreceptores/fisiología , Sinapsis/fisiología , Estimulación FísicaRESUMEN
Although many important discoveries have been made regarding the jasmonate signaling pathway, how jasmonate biosynthesis is initiated is still a major unanswered question in the field. Previous evidences suggest that jasmonate biosynthesis is limited by the availability of fatty acid precursor, such as âº-linolenic acid (âº-LA). This indicates that the lipase responsible for releasing α-LA in the chloroplast, where early steps of jasmonate biosynthesis take place, is the key initial step in the jasmonate biosynthetic pathway. Nicotiana benthamiana glycerol lipase A1 (NbGLA1) is homologous to N. attenuata GLA1 (NaGLA1) which has been reported to be a major lipase in leaves for jasmonate biosynthesis. NbGLA1 was studied for its potential usefulness in a species that is more common in laboratories. Virus-induced gene silencing of both NbGLA1 and NbGLA2, another homolog, resulted in more than 80% reduction in jasmonic acid (JA) biosynthesis in wounded leaves. Overexpression of NbGLA1 utilizing an inducible vector system failed to increase JA, indicating that transcriptional induction of NbGLA1 is insufficient to trigger JA biosynthesis. However, co-treatment with wounding in addition to NbGLA1 induction increased JA accumulation several fold higher than the gene expression or wounding alone, indicating an enhancement of the enzyme activity by wounding. Domain-deletion of a 126-bp C-terminal region hypothesized to have regulatory roles increased NbGLA1-induced JA level. Together, the data show NbGLA1 to be a major lipase for wound-induced JA biosynthesis in N. benthamiana leaves and demonstrate the use of inducible promoter-driven construct of NbGLA1 in conjunction with its transient expression in N. benthamiana as a useful system to study its protein function.
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Lipasa , Nicotiana , Oxilipinas , Nicotiana/genética , Lipasa/genética , Cloroplastos , Ciclopentanos , GlicerolRESUMEN
The innate immune system plays an essential role in regulating the immune responses to kidney transplantation, but the mechanisms through which innate immune cells influence long-term graft survival are unclear. The current study highlights the vital role of trained immunity in kidney allograft survival. Trained immunity describes the epigenetic and metabolic changes that innate immune cells undergo following an initial stimulus, allowing them have a stronger inflammatory response to subsequent stimuli. We stimulated healthy peripheral blood mononuclear cells with pretransplant and posttransplant serum of kidney transplant patients and immunosuppressive drugs in an in vitro trained immunity assay and measured tumor necrosis factor and interleukin 6 cytokine levels in the supernatant as a readout for trained immunity. We show that the serum of kidney transplant recipients collected 1 week after transplantation can suppress trained immunity. Importantly, we found that kidney transplant recipients whose serum most strongly suppressed trained immunity rarely experienced graft loss. This suppressive effect of posttransplant serum is likely mediated by previously unreported effects of immunosuppressive drugs. Our findings provide mechanistic insights into the role of innate immunity in kidney allograft survival, uncovering trained immunity as a potential therapeutic target for improving graft survival.
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OBJECTIVE: To describe the evolution of pancreas transplantation, including improved outcomes and factors associated with improved outcomes over the past 5 decades. BACKGROUND: The world's first successful pancreas transplant was performed in December 1966 at the University of Minnesota. As new modalities for diabetes treatment mature, we must carefully assess the current state of pancreas transplantation to determine its ongoing role in patient care. METHODS: A single-center retrospective review of 2500 pancreas transplants was performed over >50 years in bivariate and multivariable models. Transplants were divided into 6 eras; outcomes are presented for the entire cohort and by era. RESULTS: All measures of patient and graft survival improved progressively through the 6 transplant eras. The overall death-censored pancreas graft half-lives were >35 years for simultaneous pancreas and kidney (SPK), 7.1 years for pancreas after kidney (PAK), and 3.3 years for pancreas transplants alone (PTA). The 10-year death-censored pancreas graft survival rate in the most recent era was 86.9% for SPK recipients, 58.2% for PAK recipients, and 47.6% for PTA. Overall, graft loss was most influenced by patient survival in SPK transplants, whereas graft loss in PAK and PTA recipients was more often due to graft failures. Predictors of improved pancreas graft survival were primary transplants, bladder drainage of exocrine secretions, younger donor age, and shorter preservation time. CONCLUSIONS: Pancreas outcomes have significantly improved over time through sequential, but overlapping, advances in surgical technique, immunosuppressive protocols, reduced preservation time, and the more recent reduction of immune-mediated graft loss.
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Supervivencia de Injerto , Trasplante de Páncreas , Trasplante de Páncreas/métodos , Humanos , Estudios Retrospectivos , Adulto , Masculino , Femenino , Persona de Mediana Edad , Trasplante de Riñón , Resultado del Tratamiento , Adolescente , Niño , Adulto Joven , Tasa de SupervivenciaRESUMEN
OBJECTIVE: To generate a prediction model for selection of treatment modality for early-stage non-small cell lung cancer (NSCLC). SUMMARY BACKGROUND DATA: Stereotactic body radiotherapy (SBRT) and minimally invasive surgery (MIS) are used in the local treatment of early-stage NSCLC. However, selection of patients for either SBRT or MIS remains challenging, due to the multitude of factors influencing the decision-making process. METHODS: We analyzed 1291 patients with clinical stage I NSCLC treated with intended MIS or SBRT from January 2020 to July 2023. A prediction model for selection for SBRT was created based on multivariable logistic regression analysis. The receiver operating characteristic curve analysis stratified the cohort into 3 treatment-related risk categories. Post-procedural outcomes, recurrence and overall survival (OS) were investigated to assess the performance of the model. RESULTS: In total, 1116 patients underwent MIS and 175 SBRT. The prediction model included age, performance status, previous pulmonary resection, MSK-Frailty score, FEV1 and DLCO, and demonstrated an area-under-the-curve of 0.908 (95%CI, 0.876-0.938). Based on the probability scores (n=1197), patients were stratified into a low-risk (MIS, n=970 and SBRT, n=28), intermediate-risk (MIS, n=96 and SBRT, n=53) and high-risk category (MIS, n=10 and SBRT, n=40). Treatment modality was not associated with OS (HR of SBRT, 1.67 [95%CI: 0.80-3.48]; P=0.20). CONCLUSION: Clinical expertise can be translated into a robust predictive model, guiding the selection of stage I NSCLC patients for MIS versus SBRT and effectively categorizing them into three distinct risk groups. Patients in the intermediate category could benefit most from multidisciplinary evaluation.
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OBJECTIVE: To investigate the long-term outcomes of patients with combined primary sclerosing cholangitis/inflammatory bowel disease (PSC-IBD) undergoing both liver transplantation (LT) and total abdominal colectomy (TAC). SUMMARY BACKGROUND DATA: The fraction of patients with PSC-IBD that require both LT and TAC is small, thereby limiting significant conclusions regarding long-term outcomes. METHODS: Adult and pediatric patients from nine centers from the US IBD Surgery Collaborative who underwent staged LT and TAC for PSC-IBD were included. Long-term outcomes, including survival, were assessed. RESULTS: Among 127 patients, 66 underwent TAC-before-LT, with a median time from TAC to LT of 7.9 yrs, while 61 underwent LT-before-TAC, with a median time from LT to TAC of 4.4 years. Median patient survival post TAC was significantly worse in those undergoing LT-before-TAC (16.0 yrs vs. 42.6 yrs, P=0.007), while post LT survival was not impacted by the order of TAC and LT (21.6 yrs vs. 22.0 yrs, P=0.81). Patients undergoing TAC for medically refractory disease had a higher incidence of recurrent PSC (rPSC) (P=0.02) and biliary complications (0.09) compared to those undergoing TAC for oncologic indications. Definitive TAC reconstruction with either end ileostomy or ileal-pouch anal anastomosis (IPAA) did not impact post-LT or post-TAC outcomes. CONCLUSIONS: Long term survival in PSC-IBD was contingent upon progression to LT and was not impacted by the need for TAC. PSC-IBD patients undergoing TAC for medically refractory disease had a higher incidence of rPSC and biliary complications. The use of IPAA in PSC-IBD was a viable alternative to end ileostomy.
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Takotsubo cardiomyopathy (TCM) is an acute, stress-mediated, reversible cardiomyopathy that occurs in the absence of hemodynamically significant coronary artery disease. We aimed to investigate the characteristics and outcomes of patients who developed TCM following liver transplantation (LT) in a multicenter study. Adult patients from 6 centers across the United States who developed TCM according to Mayo Clinic criteria following LT between 2008 and 2023 were included. Demographics, perioperative and long-term outcomes, and treatment modalities were assessed. Fifty-five patients were included. The center incidence of TCM ranged from 0.1% to 0.5%. The majority were female (54.5%) and Caucasian (87.2%), and the median age at transplant was 59 years. The primary etiologies for LT were alcohol-associated cirrhosis (49.1%) and metabolic dysfunction-associated steatotic liver disease cirrhosis (21.8%). The median time from LT to TCM diagnosis was 4 days. TCM was associated with a 60.9% reduction in left ventricular ejection fraction (LVEF) from a pretransplant median LVEF of 64.0%-25.0%. The most common treatment for TCM was diuretics (67.3%) and afterload reduction (54.5%), with only 27.3% of patients requiring vasopressor support. At a median follow-up of 31.5 months, 1-year and 3-year overall survivals (OSs) were 86.3% and 69.4%, respectively. A repeat echocardiogram performed at a median of 84 days demonstrated that 45/55 patients (81.8%) had recovered LVEF ≥50%. Patients with LVEF recovery to ≥50% had significantly improved OS compared to those without LVEF recovery >50% (106.4 vs. 12.2 mo, p = 0.001). TCM following LT is associated with a significant reduction in LVEF; however, the majority of patients recover LVEF to >50% with minimal perioperative mortality. Importantly, follow-up assessment of LVEF has significant implications as lack of recovery is associated with worse OS.
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BACKGROUND: Liver transplantation (LT) is the treatment of choice for end-stage liver disease and certain malignancies such as hepatocellular carcinoma (HCC). Data on the surgical management of de novo or recurrent tumors that develop in the transplanted allograft are limited. This study aimed to investigate the perioperative and long-term outcomes for patients undergoing hepatic resection for de novo or recurrent tumors after liver transplantation. METHODS: The study enrolled adult and pediatric patients from 12 centers across North America who underwent hepatic resection for the treatment of a solid tumor after LT. Perioperative outcomes were assessed as well as recurrence free survival (RFS) and overall survival (OS) for those undergoing resection for HCC. RESULTS: Between 2003 and 2023, 54 patients underwent hepatic resection of solid tumors after LT. For 50 patients (92.6 %), resection of malignant lesions was performed. The most common lesion was HCC (n = 35, 64.8 %), followed by cholangiocarcinoma (n = 6, 11.1 %) and colorectal liver metastases (n = 6, 11.1 %). The majority of the 35 patients underwent resection of HCC did not receive any preoperative therapy (82.9 %) or adjuvant therapy (71.4 %), with resection their only treatment method for HCC. During a median follow-up period of 50.7 months, the median RFS was 21.5 months, and the median OS was 49.6 months. CONCLUSION: Hepatic resection following OLT is safe and associated with morbidity and mortality rates that are comparable to those reported for patients undergoing resection in native livers. Hepatic resection as the primary and often only treatment modality for HCC following LT is associated with acceptable RFS and OS and should be considered in well selected patients.
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Marginal Zone Lymphoma (MZL) comprises three subtypes: extranodal MZL (EMZL), splenic MZL (SMZL) and nodal MZL (NMZL). Since clinical trials have limited representativeness, there is a need for real-world data (RWD) evidence in MZL. Real-world data in Lymphoma and survival in Adults (REALYSA) is a prospective multicentric French cohort of newly diagnosed lymphoma patients. This study consists of the first abstraction of MZL patients prospectively included in REALYSA between 12/2018 and 01/2021 with at least 1 year of follow-up. It provides a landscape description of clinical characteristics, initial workup, quality of life and first-line therapy performed in routine practice. Among 207 included patients, 122 presented with EMZL, 51 with SMZL and 34 with NMZL. At baseline, median age was 67 years (range 28-96), and patients reported a favorable global health status (75/100 (IQR 58,83)) - which was higher in NMZL and lower in SMZL patients (p = 0.006). 18FDG-PET/CT was frequently performed at initial workup (EMZL 72%, SMZL 73%, NMZL 85%). Active surveillance was the initial management for 58 (28%) patients. The most prescribed therapies were rituximab-chlorambucil in the EMZL population (30%), rituximab monotherapy in the SMZL population (37%) and R-CHOP (24%)/bendamustine-rituximab (15%) in the NMZL population. At end of first line, overall response rate was 93% among treated patients with 75% of complete response. This French nationwide study provided for the first time prospective RWD on clinical characteristics, initial management and treatment response of MZL patients.
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Linfoma de Células B de la Zona Marginal , Humanos , Linfoma de Células B de la Zona Marginal/terapia , Linfoma de Células B de la Zona Marginal/patología , Linfoma de Células B de la Zona Marginal/diagnóstico , Linfoma de Células B de la Zona Marginal/epidemiología , Linfoma de Células B de la Zona Marginal/mortalidad , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Persona de Mediana Edad , Masculino , Femenino , Anciano , Adulto , Francia/epidemiología , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios Prospectivos , Rituximab/administración & dosificación , Rituximab/uso terapéutico , Tasa de Supervivencia , Estudios de SeguimientoRESUMEN
The molecular mechanisms regulating antigen translocation into the cytosol for cross-presentation are under controversial debate, mainly because direct data is lacking. Here, we have provided direct evidence that the activity of the endoplasmic reticulum (ER) translocon protein Sec61 is essential for endosome-to-cytosol translocation. We generated a Sec61-specific intrabody, a crucial tool that trapped Sec61 in the ER and prevented its recruitment into endosomes without influencing Sec61 activity and antigen presentation in the ER. Expression of this ER intrabody inhibited antigen translocation and cross-presentation, demonstrating that endosomal Sec61 indeed mediates antigen transport across endosomal membranes. Moreover, we showed that the recruitment of Sec61 toward endosomes, and hence antigen translocation and cross-presentation, is dependent on dendritic cell activation by Toll-like receptor (TLR) ligands. These data shed light on a long-lasting question regarding antigen cross-presentation and point out a role of the ER-associated degradation machinery in compartments distinct from the ER.
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Antígenos/metabolismo , Linfocitos T CD8-positivos , Reactividad Cruzada/inmunología , Citosol/metabolismo , Endosomas/metabolismo , Proteínas de la Membrana/metabolismo , Modelos Biológicos , Animales , Antígenos/inmunología , Línea Celular , Citosol/inmunología , Proteínas de la Membrana/química , Ratones , Transporte de Proteínas , Canales de Translocación SECRESUMEN
The protein encoded by COQ7 is required for CoQ10 synthesis in humans, hydroxylating 3-demethoxyubiquinol (DMQ10) in the second to last steps of the pathway. COQ7 mutations lead to a primary CoQ10 deficiency syndrome associated with a pleiotropic neurological disorder. This study shows the clinical, physiological, and molecular characterization of four new cases of CoQ10 primary deficiency caused by five mutations in COQ7, three of which have not yet been described, inducing mitochondrial dysfunction in all patients. However, the specific combination of the identified variants in each patient generated precise pathophysiological and molecular alterations in fibroblasts, which would explain the differential in vitro response to supplementation therapy. Our results suggest that COQ7 dysfunction could be caused by specific structural changes that affect the interaction with COQ9 required for the DMQ10 presentation to COQ7, the substrate access to the active site, and the maintenance of the active site structure. Remarkably, patients' fibroblasts share transcriptional remodeling, supporting a modification of energy metabolism towards glycolysis, which could be an adaptive mechanism against CoQ10 deficiency. However, transcriptional analysis of mitochondria-associated pathways showed distinct and dramatic differences between patient fibroblasts, which correlated with the extent of pathophysiological and neurological alterations observed in the probands. Overall, this study suggests that the combination of precise genetic diagnostics and the availability of new structural models of human proteins could help explain the origin of phenotypic pleiotropy observed in some genetic diseases and the different responses to available therapies.
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OBJECTIVE: To evaluate the clinically relevant anti-CD40 antibody iscalimab for baseline immunosuppression in a preclinical pig-to-rhesus renal xenograft model. SUMMARY BACKGROUND DATA: CD40/CD40L co-stimulation blockade-based immunosuppression has been more successful than calcineurin-based protocols in prolonging xenograft survival in preclinical models. METHODS: GGTA1 knockout/CD55 transgenic pig kidneys were transplanted into rhesus monkeys (n = 6) receiving an iscalimab-based immunosuppressive regimen. RESULTS: Two grafts were lost early (22 and 26 days) because of ectatic donor ureters with otherwise normal histology. The other recipients survived 171, 315, 422, and 439 days with good renal function throughout the posttransplant course. None of the recipients experienced serious infectious morbidity. CONCLUSIONS: It may be reasonable to evaluate an iscalimab-based immunosuppressive regimen in clinical renal xenotransplantation.
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Supervivencia de Injerto , Xenoinjertos , Inmunosupresores , Trasplante de Riñón , Macaca mulatta , Trasplante Heterólogo , Animales , Trasplante Heterólogo/métodos , Porcinos , Supervivencia de Injerto/inmunología , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Riñón/métodos , Inmunosupresores/farmacología , Xenoinjertos/inmunología , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/farmacología , Animales Modificados Genéticamente , Anticuerpos Monoclonales/farmacología , Humanos , Galactosiltransferasas/genéticaRESUMEN
BACKGROUND: Chronic immunosuppression following pancreas transplantation carries significant risk, including posttransplant lymphoproliferative disease (PTLD). We sought to define the incidence, risk factors, and long-term outcomes of PTLD following pancreas transplantation at a single center. METHODS: All adult pancreas transplants between February 1, 1983 and December 31, 2023 at the University of Minnesota were reviewed, including pancreas transplant alone (PTA), simultaneous pancreas-kidney transplants (SPK), and pancreas after kidney transplants (PAK). RESULTS: Among 2353 transplants, 110 cases of PTLD were identified, with an overall incidence of 4.8%. 17.3% were diagnosed within 1 year of transplant, 32.7% were diagnosed within 5 years, and 74 (67.3%) were diagnosed after 5 years. The overall 30-year incidence of PTLD did not differ by transplant type-7.4% for PTA, 14.2% for SPK, and 19.4% for PAK (p = 0.3). In multivariable analyses, older age and Epstein-Barr virus seronegativity were risk factors for PTLD, and PTLD was a risk factor for patient death. PTLD-specific mortality was 32.7%, although recipients with PTLD had similar median posttransplant survival compared to those without PTLD (14.9 year vs. 15.6 year, p = 0.9). CONCLUSIONS: PTLD following pancreas transplantation is associated with significant mortality. Although the incidence of PTLD has decreased over time, a high index of suspicion for PTLD following PTx should remain in EBV-negative recipients.
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Supervivencia de Injerto , Trastornos Linfoproliferativos , Trasplante de Páncreas , Complicaciones Posoperatorias , Humanos , Trasplante de Páncreas/efectos adversos , Masculino , Trastornos Linfoproliferativos/etiología , Trastornos Linfoproliferativos/epidemiología , Femenino , Adulto , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios de Seguimiento , Factores de Riesgo , Pronóstico , Persona de Mediana Edad , Incidencia , Tasa de Supervivencia , Estudios Retrospectivos , Rechazo de Injerto/etiología , Rechazo de Injerto/mortalidad , Trasplante de Riñón/efectos adversos , Adulto JovenRESUMEN
Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies1-7. Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength3,8. Electrical control over water transport is an attractive alternative; however, theory and simulations9-14 have often yielded conflicting results, from freezing of water molecules to melting of ice14-16 under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes17-21. Such membranes have previously been shown to exhibit ultrafast permeation of water17,22 and molecular sieving properties18,21, with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration.