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1.
Nat Immunol ; 15(12): 1152-61, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25362489

RESUMEN

The importance of autophagy in the generation of memory CD8(+) T cells in vivo is not well defined. We report here that autophagy was dynamically regulated in virus-specific CD8(+) T cells during acute infection of mice with lymphocytic choriomeningitis virus. In contrast to the current paradigm, autophagy decreased in activated proliferating effector CD8(+) T cells and was then upregulated when the cells stopped dividing just before the contraction phase. Consistent with those findings, deletion of the gene encoding either of the autophagy-related molecules Atg5 or Atg7 had little to no effect on the proliferation and function of effector cells, but these autophagy-deficient effector cells had survival defects that resulted in compromised formation of memory T cells. Our studies define when autophagy is needed during effector and memory differentiation and warrant reexamination of the relationship between T cell activation and autophagy.


Asunto(s)
Autofagia/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Memoria Inmunológica/inmunología , Animales , Separación Celular , Supervivencia Celular/inmunología , Cromatografía Liquida , Citometría de Flujo , Immunoblotting , Activación de Linfocitos/inmunología , Coriomeningitis Linfocítica/inmunología , Espectrometría de Masas , Ratones , Ratones Mutantes , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción Genética
2.
Proc Natl Acad Sci U S A ; 119(18): e2200549119, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35482926

RESUMEN

Primary mitochondrial diseases (PMDs) are a heterogeneous group of metabolic disorders that can be caused by hundreds of mutations in both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) genes. Current therapeutic approaches are limited, although one approach has been exercise training. Endurance exercise is known to improve mitochondrial function in heathy subjects and reduce risk for secondary metabolic disorders such as diabetes or neurodegenerative disorders. However, in PMDs the benefit of endurance exercise is unclear, and exercise might be beneficial for some mitochondrial disorders but contraindicated in others. Here we investigate the effect of an endurance exercise regimen in mouse models for PMDs harboring distinct mitochondrial mutations. We show that while an mtDNA ND6 mutation in complex I demonstrated improvement in response to exercise, mice with a CO1 mutation affecting complex IV showed significantly fewer positive effects, and mice with an ND5 complex I mutation did not respond to exercise at all. For mice deficient in the nDNA adenine nucleotide translocase 1 (Ant1), endurance exercise actually worsened the dilated cardiomyopathy. Correlating the gene expression profile of skeletal muscle and heart with the physiologic exercise response identified oxidative phosphorylation, amino acid metabolism, matrisome (extracellular matrix [ECM]) structure, and cell cycle regulation as key pathways in the exercise response. This emphasizes the crucial role of mitochondria in determining the exercise capacity and exercise response. Consequently, the benefit of endurance exercise in PMDs strongly depends on the underlying mutation, although our results suggest a general beneficial effect.


Asunto(s)
Enfermedades Mitocondriales , Condicionamiento Físico Animal , Animales , Humanos , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/metabolismo , Mutación , Condicionamiento Físico Animal/fisiología , Resistencia Física/genética
3.
Hum Mol Genet ; 31(9): 1430-1442, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-34788807

RESUMEN

Rahman syndrome (RMNS) is a rare genetic disorder characterized by mild to severe intellectual disability, hypotonia, anxiety, autism spectrum disorder, vision problems, bone abnormalities and dysmorphic facies. RMNS is caused by de novo heterozygous mutations in the histone linker gene H1-4; however, mechanisms underlying impaired neurodevelopment in RMNS are not understood. All reported mutations associated with RMNS in H1-4 are small insertions or deletions that create a shared frameshift, resulting in a H1.4 protein that is both truncated and possessing an abnormal C-terminus frameshifted tail (H1.4 CFT). To expand understanding of mutations and phenotypes associated with mutant H1-4, we identified new variants at both the C- and N-terminus of H1.4. The clinical features of mutations identified at the C-terminus are consistent with other reports and strengthen the support of pathogenicity of H1.4 CFT. To understand how H1.4 CFT may disrupt brain function, we exogenously expressed wild-type or H1.4 CFT protein in rat hippocampal neurons and assessed neuronal structure and function. Genome-wide transcriptome analysis revealed ~ 400 genes altered in the presence of H1.4 CFT. Neuronal genes downregulated by H1.4 CFT were enriched for functional categories involved in synaptic communication and neuropeptide signaling. Neurons expressing H1.4 CFT also showed reduced neuronal activity on multielectrode arrays. These data are the first to characterize the transcriptional and functional consequence of H1.4 CFT in neurons. Our data provide insight into causes of neurodevelopmental impairments associated with frameshift mutations in the C-terminus of H1.4 and highlight the need for future studies on the function of histone H1.4 in neurons.


Asunto(s)
Trastorno del Espectro Autista , Discapacidad Intelectual , Trastornos del Neurodesarrollo , Animales , Trastorno del Espectro Autista/genética , Mutación del Sistema de Lectura/genética , Histonas/genética , Histonas/metabolismo , Discapacidad Intelectual/genética , Discapacidad Intelectual/metabolismo , Mutación , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/metabolismo , Neuronas/metabolismo , Ratas
4.
Immunity ; 35(2): 285-98, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21856186

RESUMEN

To design successful vaccines for chronic diseases, an understanding of memory CD8(+) T cell responses to persistent antigen restimulation is critical. However, most studies comparing memory and naive cell responses have been performed only in rapidly cleared acute infections. Herein, by comparing the responses of memory and naive CD8(+) T cells to acute and chronic lymphocytic choriomeningitis virus infection, we show that memory cells dominated over naive cells and were protective when present in sufficient numbers to quickly reduce infection. In contrast, when infection was not rapidly reduced, because of high antigen load or persistence, memory cells were quickly lost, unlike naive cells. This loss of memory cells was due to a block in sustaining cell proliferation, selective regulation by the inhibitory receptor 2B4, and increased reliance on CD4(+) T cell help. Thus, emphasizing the importance of designing vaccines that elicit effective CD4(+) T cell help and rapidly control infection.


Asunto(s)
Antígenos CD/metabolismo , Infecciones por Arenaviridae/inmunología , Linfocitos T CD8-positivos/metabolismo , Virus de la Coriomeningitis Linfocítica/fisiología , Receptores Inmunológicos/metabolismo , Subgrupos de Linfocitos T/metabolismo , Enfermedad Aguda , Traslado Adoptivo , Animales , Antígenos CD/inmunología , Infecciones por Arenaviridae/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/virología , Proliferación Celular , Células Cultivadas , Enfermedad Crónica , Citocinas/inmunología , Citocinas/metabolismo , Memoria Inmunológica , Virus de la Coriomeningitis Linfocítica/patogenicidad , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Comunicación Paracrina , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores Inmunológicos/inmunología , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/patología , Subgrupos de Linfocitos T/virología , Carga Viral , Vacunas Virales
5.
Int J Toxicol ; 39(6): 530-541, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33063577

RESUMEN

INTRODUCTION: Corrected QT (QTc) interval is an essential proarrhythmic risk biomarker, but recent data have identified limitations to its use. The J to T-peak (JTp) interval is an alternative biomarker for evaluating drug-induced proarrhythmic risk. The aim of this study was to evaluate pharmacological effects using spatial magnitude leads and DII electrocardiogram (ECG) leads and common ECG confounders (ie, stress and body temperature changes) on covariate adjusted QT (QTca), covariate adjusted JTp (JTpca), and covariate adjusted T-peak to T-end (Tpeca) intervals. METHODS: Beagle dogs were exposed to body hyper- (42 °C) or hypothermic (33 °C) conditions or were administered epinephrine to assess confounding effects on heart rate corrected QTca, JTpca, and Tpeca intervals. Dofetilide (0.1, 0.3, 1.0 mg/kg), ranolazine (100, 140, 200 mg/kg), and verapamil (7, 15, 30, 43, 62.5 mg/kg) were administered to evaluate pharmacological effects. RESULTS: Covariate adjusted QT (slope -12.57 ms/°C) and JTpca (-14.79 ms/°C) were negatively correlated with body temperature but Tpeca was minimally affected. Epinephrine was associated with QTca and JTpca shortening, which could be related to undercorrection in the presence of tachycardia, while minimal effects were observed for Tpeca. There were no significant ECG change following ranolazine administration. Verapamil decreased QTca and JTpca intervals and increased Tpeca, whereas dofetilide increased QTca and JTpca intervals but had inconsistent effects on Tpeca. CONCLUSION: Results highlight potential confounders on QTc interval, but also on JTpca and Tpeca intervals in nonclinical studies. These potential confounding effects may be relevant to the interpretation of ECG data obtained from nonclinical drug safety studies with Beagle dogs.


Asunto(s)
Arritmias Cardíacas/etiología , Epinefrina/farmacología , Fenetilaminas/farmacología , Ranolazina/farmacología , Sulfonamidas/farmacología , Verapamilo/farmacología , Animales , Antiarrítmicos/administración & dosificación , Antiarrítmicos/farmacología , Arritmias Cardíacas/prevención & control , Biomarcadores , Temperatura Corporal , Perros , Relación Dosis-Respuesta a Droga , Electrocardiografía , Femenino , Frecuencia Cardíaca , Masculino , Fenetilaminas/administración & dosificación , Ranolazina/administración & dosificación , Estrés Fisiológico/efectos de los fármacos , Sulfonamidas/administración & dosificación , Verapamilo/administración & dosificación
6.
Int J Toxicol ; 38(5): 415-422, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31470746

RESUMEN

Minipigs are an emerging nonrodent alternative for ocular toxicology owing to anatomical similarities in the minipig eyes when compared to humans. Ocular structures and components from Göttingen minipigs were characterized and compared to species commonly used in toxicology. Ocular reference data from Göttingen minipig including intraocular pressure, vitreous electrolyte and thiol concentration, and electroretinography (ERG) data are essential to model characterization and data interpretation during drug safety assessments. Intravitreal positive control agents including gentamicin, indocyanine green, and glycine were used to demonstrate ERG alterations caused by retinal cell toxicity, light transmission obstruction, or neurotransmission interferences, respectively. Electrolyte concentrations of the aqueous and vitreous humors from Göttingen minipigs were similar to other species including humans. The reference data presented herein supports the use of the Göttingen minipig as an alternate nonrodent species in ocular toxicology.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Ojo/efectos de los fármacos , Modelos Animales , Porcinos Enanos , Pruebas de Toxicidad/métodos , Animales , Perros , Electrorretinografía , Macaca fascicularis , Conejos , Ratas Sprague-Dawley , Porcinos
7.
J Virol ; 91(4)2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-27974559

RESUMEN

mTOR has important roles in regulation of both innate and adaptive immunity, but whether and how mTOR modulates humoral immune responses have yet to be fully understood. To address this issue, we examined the effects of rapamycin, a specific inhibitor of mTOR, on B cell and CD4 T cell responses during acute infection with lymphocytic choriomeningitis virus. Rapamycin treatment resulted in suppression of virus-specific B cell responses by inhibiting proliferation of germinal center (GC) B cells. In contrast, the number of memory CD4 T cells was increased in rapamycin-treated mice. However, the drug treatment caused a striking bias of CD4 T cell differentiation into Th1 cells and substantially impaired formation of follicular helper T (Tfh) cells, which are essential for humoral immunity. Further experiments in which mTOR signaling was modulated by RNA interference (RNAi) revealed that B cells were the primary target cells of rapamycin for the impaired humoral immunity and that reduced Tfh formation in rapamycin-treated mice was due to lower GC B cell responses that are essential for Tfh generation. Additionally, we found that rapamycin had minimal effects on B cell responses activated by lipopolysaccharide (LPS), which stimulates B cells in an antigen-independent manner, suggesting that rapamycin specifically inhibits B cell responses induced by B cell receptor stimulation with antigen. Together, these findings demonstrate that mTOR signals play an essential role in antigen-specific humoral immune responses by differentially regulating B cell and CD4 T cell responses during acute viral infection and that rapamycin treatment alters the interplay of immune cell subsets involved in antiviral humoral immunity. IMPORTANCE: mTOR is a serine/threonine kinase involved in a variety of cellular activities. Although its specific inhibitor, rapamycin, is currently used as an immunosuppressive drug in transplant patients, it has been reported that rapamycin can also stimulate pathogen-specific cellular immunity in certain circumstances. However, whether and how mTOR regulates humoral immunity are not well understood. Here we found that rapamycin treatment predominantly inhibited GC B cell responses during viral infection and that this led to biased helper CD4 T cell differentiation as well as impaired antibody responses. These findings suggest that inhibition of B cell responses by rapamycin may play an important role in regulation of allograft-specific antibody responses to prevent organ rejection in transplant recipients. Our results also show that consideration of antibody responses is required in cases where rapamycin is used to stimulate vaccine-induced immunity.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Interacciones Huésped-Patógeno/inmunología , Inmunidad Humoral , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Apoptosis/efectos de los fármacos , Subgrupos de Linfocitos B/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Centro Germinal/inmunología , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/metabolismo , Inmunización , Memoria Inmunológica , Inmunomodulación/efectos de los fármacos , Ratones , Ratones Transgénicos , Transducción de Señal , Sirolimus/farmacología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Transducción Genética , Virosis/inmunología , Virosis/metabolismo
8.
J Virol ; 87(3): 1359-72, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23175355

RESUMEN

Adenovirus (Ad) vectors are widely used as experimental vaccines against several infectious diseases, but the magnitude, phenotype, and functionality of CD8(+) T cell responses induced by different adenovirus serotypes have not been compared. To address this question, we have analyzed simian immunodeficiency virus Gag-specific CD8(+) T cell responses in mice following vaccination with Ad5, Ad26, and Ad35. Our results show that although Ad5 is more immunogenic than Ad26 and Ad35, the phenotype, function, and recall potential of memory CD8(+) T cells elicited by these vectors are substantially different. Ad26 and Ad35 vectors generated CD8(+) T cells that display the phenotype and function of long-lived memory T cells, whereas Ad5 vector-elicited CD8(+) T cells are of a more terminally differentiated phenotype. In addition, hepatic memory CD8(+) T cells elicited by Ad26 and Ad35 mounted more robust recall proliferation following secondary challenge than those induced by Ad5. Furthermore, the boosting potential was higher following priming with alternative-serotype Ad vectors than with Ad5 vectors in heterologous prime-boost regimens. Anamnestic CD8(+) T cell responses were further enhanced when the duration between priming and boosting was extended from 30 to 60 days. Our results demonstrate that heterologous prime-boost vaccine regimens with alternative-serotype Ad vectors elicited more functional memory CD8(+) T cells than any of the regimens containing Ad5. In summary, these results suggest that alternative-serotype Ad vectors will prove useful as candidates for vaccine development against human immunodeficiency virus type 1 and other pathogens and also emphasize the importance of a longer rest period between prime and boost for generating optimal CD8(+) T cell immunity.


Asunto(s)
Adenoviridae/genética , Linfocitos T CD8-positivos/inmunología , Productos del Gen gag/inmunología , Vectores Genéticos , Memoria Inmunológica , Vacunas contra el SIDAS/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Ratones , Ratones Endogámicos C57BL , Vacunación/métodos
9.
J Immunol ; 188(1): 77-84, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22116826

RESUMEN

Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. In this study, we show that protein-energy malnutrition induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate protein (AP)-fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV)-immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that protein-energy malnutrition caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. Whereas Ag-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less responsive to polyinosinic-polycytidylic acid-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13, resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proteínas en la Dieta , Memoria Inmunológica , Deficiencia de Proteína/inmunología , Animales , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/virología , Proliferación Celular , Femenino , Coriomeningitis Linfocítica/inmunología , Coriomeningitis Linfocítica/patología , Coriomeningitis Linfocítica/virología , Virus de la Coriomeningitis Linfocítica/inmunología , Ratones , Ratones Transgénicos , Deficiencia de Proteína/genética , Deficiencia de Proteína/patología , Deficiencia de Proteína/virología
10.
Sci Adv ; 10(15): eadn0858, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38608028

RESUMEN

Miniaturized neuromodulation systems could improve the safety and reduce the invasiveness of bioelectronic neuromodulation. However, as implantable bioelectronic devices are made smaller, it becomes difficult to store enough power for long-term operation in batteries. Here, we present a battery-free epidural cortical stimulator that is only 9 millimeters in width yet can safely receive enough wireless power using magnetoelectric antennas to deliver 14.5-volt stimulation bursts, which enables it to stimulate cortical activity on-demand through the dura. The device has digitally programmable stimulation output and centimeter-scale alignment tolerances when powered by an external transmitter. We demonstrate that this device has enough power and reliability for real-world operation by showing acute motor cortex activation in human patients and reliable chronic motor cortex activation for 30 days in a porcine model. This platform opens the possibility of simple surgical procedures for precise neuromodulation.


Asunto(s)
Suministros de Energía Eléctrica , Corteza Motora , Humanos , Animales , Porcinos , Reproducibilidad de los Resultados
11.
J Am Vet Med Assoc ; : 1-7, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39059431

RESUMEN

OBJECTIVE: To determine whether urea nitrogen and creatinine levels differ in lacrimal fluid (LF) and serum (SER) in nonazotemic (control) and azotemic dogs and whether there is an agreement between LF and SER. METHODS: A prospective observational study was performed at the Auburn University Small Animal Teaching Hospital between May 2023 and March 2024. Forty control and 38 azotemic dogs were enrolled. Twenty microliters of LF per eye was collected with microcapillary tubes, and 3 mL of blood was drawn. Bland-Altman plot and intraclass correlation coefficient (ICC) were used to evaluate the agreement between LF and SER. RESULTS: There was good agreement between LF and SER levels of urea nitrogen in the control group (Bland-Altman plot mean bias of -0.8108 ± 2.407 mg/dL; ICC of 0.874 [95% CI, 0.773 to 0.934]) and the azotemic group (Bland-Altman plot mean bias of -9.681 ± 23.89 mg/dL; ICC of 0.82 [95% CI, 0.658 to 0.906]). There was poor agreement between LF and SER concentrations for creatinine in the control and azotemic groups, with only 26 dogs with creatinine detectable in LF. CONCLUSIONS: Lacrimal fluid and SER concentrations of urea nitrogen showed good agreement in both the control and azotemic groups, whereas poor agreement was found for creatinine in both groups. CLINICAL RELEVANCE: Measurement of urea nitrogen in LF may provide an alternative to blood for diagnosing uremia. However, additional research is necessary before substituting LF for SER.

12.
Mol Pharm ; 10(12): 4590-4602, 2013 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-24152340

RESUMEN

Plant or microbial lectins are known to exhibit potent antiviral activities against viruses with glycosylated surface proteins, yet the mechanism(s) by which these carbohydrate-binding proteins exert their antiviral activities is not fully understood. Hepatitis C virus (HCV) is known to possess glycosylated envelope proteins (gpE1E2) and to be potently inhibited by lectins. Here, we tested in detail the antiviral properties of the newly discovered Microcystis viridis lectin (MVL) along with cyanovirin-N (CV-N) and Galanthus nivalis agglutinin (GNA) against cell culture HCV, as well as their binding properties toward viral particles, target cells, and recombinant HCV glycoproteins. Using infectivity assays, CV-N, MVL, and GNA inhibited HCV with IC50 values of 0.6 nM, 30.4 nM, and 11.1 nM, respectively. Biolayer interferometry analysis demonstrated a higher affinity of GNA to immobilized recombinant HCV glycoproteins compared to CV-N and MVL. Complementary studies, including fluorescence-activated cell sorting (FACS) analysis, confocal microscopy, and pre- and post-virus binding assays, showed a complex mechanism of inhibition for CV-N and MVL that includes both viral and cell association, while GNA functions by binding directly to the viral particle. Combinations of GNA with CV-N or MVL in HCV infection studies revealed synergistic inhibitory effects, which can be explained by different glycan recognition profiles of the mainly high-mannoside specific lectins, and supports the hypothesis that these lectins inhibit through different and complex modes of action. Our findings provide important insights into the mechanisms by which lectins inhibit HCV infection. Overall, the data suggest MVL and CV-N have the potential for toxicity due to interactions with cellular proteins while GNA may be a better therapeutic agent due to specificity for the HCV gpE1E2.


Asunto(s)
Antivirales/farmacología , Proteínas Bacterianas/farmacología , Proteínas Portadoras/farmacología , Hepacivirus/efectos de los fármacos , Lectinas de Unión a Manosa/farmacología , Microcystis/metabolismo , Lectinas de Plantas/farmacología , Línea Celular Tumoral , Cianobacterias/metabolismo , Glicoproteínas/metabolismo , Humanos , Proteínas Recombinantes/farmacología
13.
Proc Natl Acad Sci U S A ; 107(33): 14733-8, 2010 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-20679213

RESUMEN

Inhibitory receptors play a crucial role in regulating CD8 T-cell function during chronic viral infection. T-cell Ig- and mucin-domain-containing molecule-3 (Tim-3) is well known to negatively regulate T-cell responses, but its role in CD8 T-cell exhaustion during chronic infection in vivo remains unclear. In this study, we document coregulation of CD8 T cell exhaustion by Tim-3 and PD-1 during chronic lymphocytic choriomeningitis virus infection. Whereas Tim-3 was only transiently expressed by CD8 T cells after acute infection, virus-specific CD8 T cells retained high Tim-3 expression throughout chronic infection. The majority (approximately 65% to 80%) of lymphocytic choriomeningitis virus-specific CD8 T cells in lymphoid and nonlymphoid organs coexpressed Tim-3 and PD-1. This coexpression of Tim-3 and PD-1 was associated with more severe CD8 T-cell exhaustion in terms of proliferation and secretion of effector cytokines such as IFN-gamma, TNF-alpha, and IL-2. Interestingly, CD8 T cells expressing both inhibitory receptors also produced the suppressive cytokine IL-10. Most importantly, combined blockade of Tim-3 and PD-1 pathways in vivo synergistically improved CD8 T cell responses and viral control in chronically infected mice. Taken together, our study defines a parameter for determining the severity of CD8 T cell dysfunction and for identifying virus-specific CD8 T cells that produce IL-10, and shows that targeting both PD-1 and Tim-3 is an effective immune strategy for treating chronic viral infections.


Asunto(s)
Antígenos de Superficie/inmunología , Proteínas Reguladoras de la Apoptosis/inmunología , Linfocitos T CD8-positivos/inmunología , Coriomeningitis Linfocítica/inmunología , Receptores Virales/inmunología , Animales , Anticuerpos Bloqueadores/inmunología , Anticuerpos Bloqueadores/farmacología , Antígenos de Superficie/metabolismo , Antígenos Virales/inmunología , Proteínas Reguladoras de la Apoptosis/metabolismo , Linfocitos T CD8-positivos/metabolismo , Enfermedad Crónica , Femenino , Citometría de Flujo , Receptor 2 Celular del Virus de la Hepatitis A , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Coriomeningitis Linfocítica/virología , Virus de la Coriomeningitis Linfocítica/inmunología , Ratones , Ratones Endogámicos C57BL , Receptor de Muerte Celular Programada 1 , Receptores Virales/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
14.
J Clin Med ; 12(22)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38002575

RESUMEN

This case report presents a 26-year-old female patient diagnosed with fundus albipunctatus (FAP), a rare form of congenital stationary night blindness. The patient's clinical history and retinal findings spanning 23 years are consistent with FAP. The patient has profound night blindness, photophobia, and mild color vision changes with preserved best-corrected visual acuity (BCVA). Small white dots are present throughout the fundus, sparing the central macula. Electroretinograms (ERG) are consistent with congenital stationary night blindness (CSNB) and suggest a lack of rod response. Ophthalmic imaging has remained stable over time. Genetic testing revealed two biallelic missense mutations in the LRAT gene, c.197G>A (p.Gly66Glu) and c.557A>C (p.Lys186Thr). LRAT mutations are known to contribute to other retinal conditions but have not been previously associated with FAP. While there are currently no available treatments for FAP, this report expands our understanding of the genetic landscape of FAP to include LRAT and provides clinical data to support this finding.

15.
Vision Res ; 208: 108221, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37001420

RESUMEN

Blue cone monochromacy (BCM) is a congenital vision disorder characterized by complete loss or severely reduced long- and middle-wavelength cone function, caused by mutations in the OPN1LW/OPN1MW gene cluster on the X-chromosome. BCM patients typically suffer from poor visual acuity, severely impaired color discrimination, myopia, and nystagmus. In this review, we cover the genetic causes of BCM, clinical features of BCM patients, genetic testing, and clinical outcome measurements for future BCM clinical trials. However, our emphasis is on detailing the animal models for BCM and gene therapy using adeno-associated vectors (AAV). We describe two mouse models resembling the two most common causes of BCM, current progress in proof-of-concept studies to treat BCM with deletion mutations, the challenges we face, and future directions.


Asunto(s)
Defectos de la Visión Cromática , Animales , Ratones , Defectos de la Visión Cromática/genética , Defectos de la Visión Cromática/terapia , Mutación , Terapia Genética , Células Fotorreceptoras Retinianas Conos , Opsinas de Bastones/genética
16.
Data Brief ; 42: 108290, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35664655

RESUMEN

A better understanding of how the spatial configuration of cities, understood as urban structure and forms, can achieve sustainable development is needed. This paper presents spatial data and an automated workflow for studying the urban structures (i.e., road and transportation networks) and forms (i.e., building size, position, function and density) of two medium-sized European cities - Bergen, Norway and Zürich, Switzerland. The data focuses on examining correlations between the densification patterns and transport energy usage of these cities de Koning et al., (2020). Spatial and tabular datasets for (i) urban structures, (ii) urban forms, (iii) building density, (iv) road centre lines and (v) transport energy usage are obtained as georeferenced files from OpenStreetMap (OSM) and upon request from collaborating local and national authorities. Transport energy data is derived from traffic data collected from the Norwegian Public Road Authorities or simulated via a traffic model. Open-source data is used wherever possible. Data gaps within proprietary data are supplemented with proxies or open-source data. Hand-drawn axial maps drawn by the authors using the Space Syntax methods and analysed via depthmapX software are a crucial dataset presented here. All analysed data are then returned to a Geographical Information System (GIS) platform and processed via an automated workflow of 19 steps built via the ModelBuilderTM tool in ESRI® ArcGIS. The automated workflow allows for repetitive cross-city comparison and the compilation of diverse spatial data sources for analysis. In combination with the novel workflow, the dataset can be used for future comparative studies in spatial planning, transport planning and management of energy systems to facilitate informed decision-making towards more sustainable developments.

17.
Mol Metab ; 64: 101560, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35940554

RESUMEN

OBJECTIVE: Mitochondrial disorders are often characterized by muscle weakness and fatigue. Null mutations in the heart-muscle adenine nucleotide translocator isoform 1 (ANT1) of both humans and mice cause cardiomyopathy and myopathy associated with exercise intolerance and muscle weakness. Here we decipher the molecular underpinnings of ANT1-deficiency-mediated exercise intolerance. METHODS: This was achieved by correlating exercise physiology, mitochondrial function and metabolomics of mice deficient in ANT1 and comparing this to control mice. RESULTS: We demonstrate a peripheral limitation of skeletal muscle mitochondrial respiration and a reduced complex I respiration in ANT1-deficient mice. Upon exercise, this results in a lack of NAD+ leading to a substrate limitation and stalling of the TCA cycle and mitochondrial respiration, further limiting skeletal muscle mitochondrial respiration. Treatment of ANT1-deficient mice with nicotinamide riboside increased NAD+ levels in skeletal muscle and liver, which increased the exercise capacity and the mitochondrial respiration. CONCLUSION: Increasing NAD+ levels with nicotinamide riboside can alleviate the exercise intolerance associated to ANT1-deficiency, indicating the therapeutic potential of NAD+-stimulating compounds in mitochondrial myopathies.


Asunto(s)
Translocador 1 del Nucleótido Adenina , Miopatías Mitocondriales , NAD , Niacinamida , Condicionamiento Físico Animal , Compuestos de Piridinio , Translocador 1 del Nucleótido Adenina/genética , Animales , Ratones , Miopatías Mitocondriales/genética , Debilidad Muscular , Niacinamida/análogos & derivados , Niacinamida/farmacología , Isoformas de Proteínas , Compuestos de Piridinio/farmacología
18.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 67(Pt 11): 1350-8, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22102230

RESUMEN

In Gram-negative bacteria, the BAM complex catalyzes the essential process of assembling outer membrane proteins. The BAM complex in Escherichia coli consists of five proteins: one ß-barrel membrane protein, BamA, and four lipoproteins, BamB, BamC, BamD and BamE. Here, the crystal structure of the C-terminal domain of E. coli BamC (BamC(C): Ala224-Ser343) refined to 1.5 Å resolution in space group H3 is reported. BamC(C) consists of a six-stranded antiparallel ß-sheet, three α-helices and one 3(10)-helix. Sequence and surface analysis reveals that most of the conserved residues within BamC(C) are localized to form a continuous negatively charged groove that is involved in a major crystalline lattice contact in which a helix from a neighbouring BamC(C) binds against this surface. This interaction is topologically and architecturally similar to those seen in the substrate-binding grooves of other proteins with BamC-like folds. Taken together, these results suggest that an identified surface on the C-terminal domain of BamC may serve as an important protein-binding surface for interaction with other BAM-complex components or substrates.


Asunto(s)
Proteínas de Escherichia coli/química , Escherichia coli/química , Proteínas Ligadas a Lípidos/química , Secuencia de Aminoácidos , Cristalografía por Rayos X , Proteínas de Escherichia coli/aislamiento & purificación , Proteínas Ligadas a Lípidos/aislamiento & purificación , Modelos Moleculares , Datos de Secuencia Molecular , Pliegue de Proteína , Estructura Terciaria de Proteína , Alineación de Secuencia , Homología Estructural de Proteína , Propiedades de Superficie
19.
Elife ; 102021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-34003111

RESUMEN

Germlines shape and balance heredity, integrating and regulating information from both parental and foreign sources. Insights into how germlines handle information have come from the study of factors that specify or maintain the germline fate. In early Caenorhabditis elegans embryos, the CCCH zinc finger protein PIE-1 localizes to the germline where it prevents somatic differentiation programs. Here, we show that PIE-1 also functions in the meiotic ovary where it becomes SUMOylated and engages the small ubiquitin-like modifier (SUMO)-conjugating machinery. Using whole-SUMO-proteome mass spectrometry, we identify HDAC SUMOylation as a target of PIE-1. Our analyses of genetic interactions between pie-1 and SUMO pathway mutants suggest that PIE-1 engages the SUMO machinery both to preserve the germline fate in the embryo and to promote Argonaute-mediated surveillance in the adult germline.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , ARN Interferente Pequeño/genética , Sumoilación/genética , Animales , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Caenorhabditis elegans/metabolismo , Diferenciación Celular , Femenino , Meiosis , Óvulo , ARN Interferente Pequeño/metabolismo
20.
Indian J Nephrol ; 29(4): 288-290, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31423065

RESUMEN

Acute renal cortical necrosis (ACN) is a potentially fatal renal condition. Our objective is to report a case of ACN in a young man who had developed premature atherosclerotic vascular disease and required intermittent hemodialysis support. His renal biopsy showed diffuse cortical necrosis. Subsequently, 2 weeks after the renal insult, he developed a cardioembolic stroke and was anticoagulated with low-molecular-weight heparin. Thrombophilia screen revealed elevated serum homocystein and he was treated with folate supplement and vitamin B12 injection. With these treatments, he had partial renal recovery and became dialysis independent. In conclusion, this is a rare case of ACN, which may have occurred as a complication of hyperhomocysteinemia.

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