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1.
PLoS One ; 19(8): e0308330, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39116074

RESUMEN

The immunogenicity of cancer cells is influenced by several factors, including the expression of the major histocompatibility complex class I (MHC-I), antigen expression, and the repertoire of proteasome-produced epitope peptides. The malignant pleural mesothelioma cell line ACC-MEOS-4 (MESO-4) expresses high levels of MHC-I and Wilms tumor 1 (WT1) tumor antigens. Using a functional T cell reporter assay specific for the HLA-A*24:02 restricted WT1 epitope (WT1235, CMTWNQMNL), we searched for factors that augmented the immunogenicity of MESO-4, focusing on proteasomes, which have a central role in the antigen processing machinery. ONX-0914, a selective inhibitor of the immunoproteasome subunit ß5i, enhanced immunogenicity dose-dependently at low concentrations without cytotoxicity. In addition, CD8+ T lymphocytes recognizing WT1 showed greater cytotoxicity against MESO-4 pre-treated with ONX-0914. MESO-4 expresses a standard proteasome (SP) and immunoproteasome (IP). Notably, IP has distinct catalytic activity from SP, favoring the generation of antigenic peptides with high affinity for MHC-I in antigen-presenting cells and cancer cells. In vitro, immunoproteasome digestion assay and mass spectrometry analysis showed that IP cleaved WT1235 internally after the hydrophobic residues. Importantly, this internal cleavage of the WT1235 epitope was mitigated by ONX-0914. These results suggest that ONX-0914 prevents the internal destructive cleavage of WT1235 by IP, thereby promoting the specific presentation of the WT1 epitope by MESO-4. In conclusion, selective IP inhibitors might offer a means to modulate cancer cell immunogenicity by directing the presentation of particular tumor epitopes.


Asunto(s)
Mesotelioma , Complejo de la Endopetidasa Proteasomal , Inhibidores de Proteasoma , Proteínas WT1 , Humanos , Línea Celular Tumoral , Proteínas WT1/inmunología , Inhibidores de Proteasoma/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Complejo de la Endopetidasa Proteasomal/inmunología , Mesotelioma/inmunología , Mesotelioma/tratamiento farmacológico , Epítopos/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Antígeno HLA-A24/inmunología , Mesotelioma Maligno/inmunología , Mesotelioma Maligno/tratamiento farmacológico , Epítopos de Linfocito T/inmunología , Oligopéptidos
2.
Cell Rep ; 43(7): 114354, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38906147

RESUMEN

Female mosquitoes engage in blood feeding from their hosts to facilitate egg maturation but cease feeding once a sufficient blood meal has been acquired. Abdominal distention has been proposed as a contributing factor; however, it has also been suggested that there are chemical controls. In this study, we focus on negative chemical regulators of blood feeding, particularly those present in the host blood. Serum derived from animal blood inhibits the feeding of ATP, a phagostimulant of blood feeding in Aedes aegypti. Fibrinopeptide A (FPA), a 16-amino acid peptide cleaved from fibrinogen during blood coagulation, serves as an inhibitory factor in the serum. Our findings suggest that blood-feeding arrest in female mosquitoes is triggered by the detection of FPA in the host blood, which increases as blood coagulation proceeds in the mosquito's midgut, highlighting the role of host-derived substances as negative regulators of mosquito behavior.


Asunto(s)
Aedes , Animales , Aedes/fisiología , Femenino , Conducta Alimentaria , Fiebre Amarilla/transmisión , Mosquitos Vectores
3.
Anal Biochem ; 671: 115155, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37059321

RESUMEN

Exhaled gas analysis is a non-invasive test ideal for continuous monitoring of biological metabolic information. We analyzed the exhaled gas of patients with inflammatory diseases for trace gas components that could serve as biomarkers that enable early detection of inflammatory diseases and assessment of treatment efficacy. Furthermore, we examined the clinical potential of this method. We enrolled 34 patients with inflammatory disease and 69 healthy participants. Volatile components from exhaled gas were collected and analyzed by a gas chromatography-mass spectrometry system, and the data were examined for gender, age, inflammatory markers, and changes in markers before and after treatment. The data were tested for statistical significance through discriminant analysis by Volcano plot, Analysis of variance test, principal component analysis, and cluster analysis comparing healthy and patient groups. There were no significant differences in the trace components of exhaled gas by gender or age. However, we found differences in some components of the exhaled gas between healthy and untreated patients. In addition, after treatment, gas patterns including the patient-specific components changed to a state closer to the inflammation-free status. We identified trace components in the exhaled gas of patients with inflammatory diseases and found that some of these regressed after treatment.


Asunto(s)
Compuestos Orgánicos Volátiles , Humanos , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Orgánicos Volátiles/análisis , Pruebas Respiratorias/métodos , Biomarcadores/análisis , Espiración
4.
J Inherit Metab Dis ; 46(1): 143-152, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36220782

RESUMEN

Fabry disease (FD) is an X-linked inherited lysosomal metabolism disorder in which globotriaosylceramide (Gb3) accumulates in various organs resulting from a deficiency in alpha-galactosidase A. The clinical features of FD include progressive impairments of the renal, cardiac, and peripheral nervous systems. In addition, patients with FD often develop neuropsychiatric symptoms, such as depression and dementia, which are believed to be induced by the cellular injury of cerebrovascular and partially neuronal cells due to Gb3 accumulation. Although the analysis of autopsy brain tissue from patients with FD showed no accumulation of Gb3, abnormal deposits of Gb3 were found in the neurons of several brain areas, including the hippocampus. Therefore, in this study, we generated induced pluripotent stem cells (iPSCs) from patients with FD and differentiated them into neuronal cells to investigate pathological and biological changes in the neurons of FD. Neural stem cells (NSCs) and neurons were successfully differentiated from the iPSCs we generated; however, cellular damage and morphological changes were not found in these cells. Immunostaining revealed no Gb3 accumulation in NSCs and neurons. Transmission electron microscopy did not reveal any zebra body-like structures or inclusion bodies, which are characteristic of FD. These results indicated that neuronal cells derived from FD-iPSCs exhibited normal morphology and no Gb3 accumulation. It is likely that more in vivo environment-like cultures are needed for iPSC-derived neurons to reproduce disease-specific features.


Asunto(s)
Enfermedad de Fabry , Células Madre Pluripotentes Inducidas , Masculino , Humanos , Enfermedad de Fabry/genética , Células Madre Pluripotentes Inducidas/patología , alfa-Galactosidasa/genética , alfa-Galactosidasa/metabolismo , Fenotipo , Neuronas/metabolismo , Trihexosilceramidas/metabolismo
5.
Mol Genet Metab Rep ; 31: 100852, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35782608

RESUMEN

The pathological consequences leading to primary storage, autophagy impairment, impaired mitochondrial dynamics, and endoplasmic reticulum (ER) stress on neural cell dysfunction and apoptosis in metachromatic leukodystrophy (MLD) have been poorly elucidated. In the present study, we generated 2 cell lines of patient-specific-induced pluripotent stem cells (iPSCs) and modeled the progression of pathological events during the differentiation of iPSCs to motor neuron progenitors (MNPs) and mature motor neurons (MNs). The iPS cells were generated from two late-infantile MLD patient-derived skin fibroblasts using electroporation or the Sendai virus. Olig2+ MNPs were generated from both iPSC lines using a combination of small molecules in a chemically defined neural medium. Furthermore, the MNPs could be differentiated into mature MNs, which was confirmed by RT-PCR and MN markers, including SMI32 and ChAT. The population of MNs was approximately 50% under the culture conditions. Pathological observation of MLD patient-derived iPSCs revealed lysosomal accumulation and impaired autophagy. In addition, both MNPs and MNs derived from MLD-iPSCs showed increased lysosomal accumulation, dysfunctional autophagy, impaired mitophagy, endoplasmic reticulum (ER) stress or unfolded protein response (UPR) activation, and premature cellular death.

6.
Mycoscience ; 63(6): 284-292, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37089524

RESUMEN

The N-terminal amino acid sequence of the Pleurotus sp. 90 kDa protein was in good agreement with the corresponding sequence of the glycoside hydrolase (GH) family 37 protein (trehalase) from P. ostreatus PC 15 v2.0. The length of the Pleurotus sp. trehalase gene was 2247 bp, encoding a protein of 749 amino acids with a predicted molecular mass of 81.2 kDa. The molecular mass of the recombinant enzyme was estimated to be about 117 kDa by SDS-PAGE. We found that the recombinant enzyme comprised an N-glycosylated sugar chain and that its optimum pH and temperature were 4.5 and 40 ºC, respectively. Moreover, this enzyme exhibited high activity against trehalose exclusively. We found that the enzyme is novel acid trehalase belonging to GH family 37.

7.
Sci Rep ; 11(1): 21840, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34750445

RESUMEN

Research has previously shown that ultraviolet light C (UV-C) can inactivate unexpected infection. However, this type of potential disinfection is dramatically reduced for the shadow area such as under desk or medical equipment. Because the UV-C reflectance ratio is low on the general wall surfaces. We compared Stucco against the other materials to investigate whether we could improve disinfection for the shadow area. The reflectance ratios of UV-C irradiation of each material were examined, with particular attention to the rates for the author's Modified Stucco. To evaluate the disinfection effects of the UV-C reflective lighting, colonies of E. coli and of Staphylococcus hominis were cultured in an agar media and counted over a certain time period after applying UV-C irradiation from a sterilizing lamp onto the investigation materials. The author's Modified Stucco, produced reflectance ratios that was 11 times that of white wallpaper. This demonstrated that the UV-C reflected on the Stucco wall having optimum components and their compositions inhibited the number of E. coli and S. hominis, resulting in significantly disinfection effects on white wallpapers. The space with Modified Stucco and then irradiated by a UV-C may give a strong disinfection effect.

8.
Heterocycles ; 103(1): 231-248, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34566248

RESUMEN

Firefly luciferase is used in high-throughput screening based on the detection of chemiluminescence. It catalyzes an esterification reaction of luciferin with adenosine 5'-triphosphate (ATP) followed by decarbonylation with oxygen and concomitance of light. Previously, we reported that firefly luciferase also possesses acyl-CoA synthetase activity and catalyzes an aromatic carboxylic acid group of F-53, using ATP, Mg2+ and coenzyme A (CoA), to produce F-53 covalently attached to active-site lysine-529 residue of firefly luciferase through the formation of an amide group. The amidation of lysine-529 resulted in a deactivation of luciferase. In order to probe firefly luciferase inhibition's mechanism, we synthesized two probe molecules 1 and 2, mimicking F-53. Molecule 1 contains an azido-appended side chain in the aromatic ring of F-53, while 2 possesses an azido and a carboxylic acid group appended side chains. Both synthetic schemes are readily amenable to large-scale syntheses. Molecule 1 was made from 2-allylaniline, which was derived from a thermal-induced aromatic-Claisen rearrangement of N-allylaniline. The azido-appended side chain of 2 was installed from a Horner-Wadsworth-Emmons reaction and the carboxylic acid side chain from a Sonogashira reaction.

9.
Mol Genet Metab Rep ; 28: 100784, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34377675

RESUMEN

Niemann-Pick disease type C (NPC) is a rare neurodegenerative disorder caused by a recessive mutation in the NPC1 or NPC2 gene, in which patients exhibit lysosomal accumulation of unesterified cholesterol and glycolipids. Most of the research on NPC has been done in patient-derived skin fibroblasts or mouse models. Therefore, we developed NPC patient neurons derived from induced pluripotent stem cells (iPSCs) to investigate the neuropathological cause of the disease. Although an accumulation of cholesterol and glycolipids, which is characteristic of NPC, was observed in both undifferentiated iPSCs and derived neural stem cells (NSCs), we could not observed the abnormalities in differentiation potential and autophagic activity in such immature cells. However, definite neuropathological features were detected in mature neuronal cells generated from NPC patient-derived iPSCs. Abnormal accumulation of cholesterol and other lipids identified by lipid droplets and number of enlarged lysosomes was more prominent in mature neuronal cells rather than in iPSCs and/or NSCs. Thin-sectioning electron microscopic analysis also demonstrated numerous typical membranous cytoplasmic bodies in mature neuronal cells. Furthermore, TUJ1-positive neurite density was significantly reduced in NPC patient-derived neuronal cells. In addition, disruption of the p62/SQSTM1-KEAP1-NRF2 axis occurred in neurons differentiated from NPC patient-derived iPSCs. These data indicate the impairment of neuronal network formation associated with neurodegeneration in mature neuronal cells derived from patients with NPC.

10.
PeerJ ; 9: e10638, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33505803

RESUMEN

BACKGROUND: Banana juice is becoming a popular beverage in Japan and the number of soft-drink stands or shops that take great care and pride in the quality of their products has been increasing. This study aims to measure the scent of banana juice from different brands using the electronic (e-) nose FF-2A in order to identify the characteristics, time-related changes, and the differences among them. METHODS: We standardized the scent value of banana juice measured using FF-2A and determined the absolute value in three different shops. We compared the similarities in samples from each shop with axis data created using standardized measurement. With FF-2A we identified the scent common to all banana juice samples from the composite scent and numerically showed the similarity to the reference gas. RESULTS: The juices from each shop had their own characteristics and we were able to identify the difference between some of these. The response of FF-2A varied according to the increase/decrease in the number of characteristic molecules measured by GC-MS such as overtime fluctuations in the gas. These data were shown along with the differences between the various banana juices. CONCLUSIONS: FF-2A was able to identify the scent of banana juice at each banana shop as well as time-related changes. By combining GC-MS, we were able to evaluate scent components that changed over time. The results using the electronic nose may prove useful for objective evaluation and comparison of scent with other types of juices.

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