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1.
Immunology ; 172(2): 313-327, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38462236

RESUMEN

This study longitudinally evaluated the immune response in individuals over a year after receiving three doses of an inactivated SARS-CoV-2 vaccine, focusing on reactions to Omicron breakthrough infections. From 63 blood samples of 37 subjects, results showed that the third booster enhanced the antibody response against Alpha, Beta, and Delta VOCs but was less effective against Omicron. Although antibody titres decreased post-vaccination, SARS-CoV-2-specific T-cell responses, both CD4+ and CD8+, remained stable. Omicron breakthrough infections significantly improved neutralization against various VOCs, including Omicron. However, the boost in antibodies against WT, Alpha, Beta, and Delta variants was more pronounced. Regarding T cells, breakthrough infection predominantly boosted the CD8+ T-cell response, and the intensity of the spike protein-specific T-cell response was roughly comparable between WT and Omicron BA.5.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Vacunas de Productos Inactivados , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , SARS-CoV-2/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Masculino , Femenino , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Adulto , Persona de Mediana Edad , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Linfocitos T CD8-positivos/inmunología , Vacunación/métodos , Inmunización Secundaria , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T CD4-Positivos/inmunología , Anciano , Linfocitos T/inmunología , Infección Irruptiva
2.
Dokl Biochem Biophys ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023671

RESUMEN

Stroke is recognized as a leading cause of disability and mortality worldwide, posing a significant challenge, particularly in developing countries. The current study aimed to evaluate the neuroprotective effect of Ganoderic acid (GA) against focal ischemic stroke in rats. MATERIAL AND METHODS: Swiss Wistar rats were used for the current study. The rats were subjected to middle cerebral artery occlusion (MCAO) to simulate transient focal ischemia, followed by reperfusion. Various neurological parameters, including infarct size, neurological deficit score, brain water content, Evans blue leakage, nitric oxide (NO), inducible nitric oxide synthase (iNOS), lactate dehydrogenase (LDH), antioxidant levels, inflammatory cytokines, apoptosis markers, inflammatory parameters, and matrix metalloproteinases (MMP) levels, were estimated. Additionally, mRNA expressions were evaluated in the brain tissue. RESULTS: Dose dependently treatment of GA significantly (P < 0.001) suppressed the infarct size, neurological deflects score, brain water, evans blue leakage, NO, iNOS, LDH, C-X-C chemokine receptor type 4 (CXCR-4), monocyte chemoattractant protein-1 (MCP-1), S100 calcium-binding protein B (S-100ß) and K+-Cl- cotransporter 1 (KCC1) positive cells. GA altered the level of oxidative stress parameters like Total antioxidant capacity (T-AOC), 8-hydroxy-2'-deoxyguanosine (8-OhdG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), malonaldehyde (MDA); cytokines viz., tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), IL-1ß, IL-6, IL-9, IL-10; inflammatory parameters such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), prostaglandin (PGE2), Nuclear factor kappa B (NF-κB); apoptosis parameters like B-cell leukemia/lymphoma 2 protein (Bcl-2), Bcl-2-associated protein x (Bax), Caspase-3; matrix metallopeptidase (MMP) parameters like MMP-2, MMP-3, and MMP-9, respectively. GA remarkably suppressed the mRNA expression of TRL-4, Syndecan-1, CSF, Aquaporin-1, OCT3, and RFX1. CONCLUSION: Ganoderic acid exhibited the protection against the cerebral ischemia reperfusion via multiple mechanism.

3.
J Med Virol ; 95(3): e28670, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36916726

RESUMEN

Chronic hepatitis B virus (HBV) infection has been characterized by lack of effective adaptive immune responses which are vital for the viral clearance. However, very little is known about the dynamics of adaptive immune responses during the early phase of chronic HBV infection especially in spleen and liver. Here, we used the hydrodynamic injection (HDI) mouse model to kinetically characterize differences in the features of adaptive immunity, including the frequencies, phenotypes and function of antigen-presenting cells and T cells in the spleen, peripheral blood mononuclear cells (PBMCs) and liver, of chronic versus acute-resolving HBV replication (AR). We found that mice with AR mice and mice with chronic HBV replication (CH) mice showed early splenomegaly accompanied by T cell expansion in spleen but not in liver after HDI. Interestingly, the early and continuous increase in HBV-specific CD8+ T cells in spleen of CH mice was comparable to that in the AR mice. However, the splenic T cells of CH mice showed no activation phenotype compared with those in AR mice. Besides, increases in activated effector CD8+ T cells in PBMCs and liver at later time points were only observed in AR mice but not CH mice. CH mice also showed insufficient expansion of dendritic cells (DCs) in spleen and increased programmed death-1 expression in DCs of the liver compared to AR mice. The adoptive transfer of total splenocytes or splenic CD8+ T cells of AR mice to CH mice demonstrated that their ability to break HBV tolerance varies at different stages of HBV clearance. Moreover, the adoptive transfer of splenocytes from AR mice induce functional activation of endogenous HBV-specific CD8+ T cells of CH mice. Our results suggest that early T cell priming and expansion initially happens in the periphery after HBV antigen exposure in acute-resolving and chronic replication. The paucity of T cell activation, and subsequent migration and liver infiltration is a key feature of the adaptive immune responses during the early phase of CH, which is probably caused by the dysfunction of DCs.


Asunto(s)
Hepatitis B Crónica , Ratones , Animales , Virus de la Hepatitis B/genética , Leucocitos Mononucleares , Hígado , Linfocitos T CD8-positivos , Inmunidad Adaptativa
4.
Int J Mol Sci ; 24(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37175445

RESUMEN

Stem-cell-based therapy is very promising for Alzheimer's disease (AD), yet has not become a reality. A critical challenge is the transplantation microenvironment, which impacts the therapeutic effect of stem cells. In AD brains, amyloid-beta (Aß) peptides and inflammatory cytokines continuously poison the tissue microenvironment, leading to low survival of grafted cells and restricted efficacy. It is necessary to create a growth-supporting microenvironment for transplanted cells. Recent advances in AD studies suggest that the asparaginyl endopeptidase (AEP) is a potential intervention target for modifying pathological changes. We here chose APP/PS1 mice as an AD model and employed pharmacological inhibition of the AEP for one month to improve the brain microenvironment. Thereafter, we transplanted neural stem cells (NSCs) into the hippocampus and maintained therapy for one more month. We found that inhibition of AEPs resulted in a significant decrease of Aß, TNF-α, IL-6 and IL-1ß in their brains. In AD mice receiving NSC transplantation alone, the survival of NSCs was at a low level, while in combination with AEP inhibition pre-treatment the survival rate of engrafted cells was doubled. Within the 2-month treatment period, implantation of NSCs plus pre-inhibition of the AEP significantly enhanced neural plasticity of the hippocampus and rescued cognitive impairment. Neither NSC transplantation alone nor AEP inhibition alone achieved significant efficacy. In conclusion, pharmacological inhibition of the AEP ameliorated brain microenvironment of AD mice, and thus improved the survival and therapeutic efficacy of transplanted stem cells.


Asunto(s)
Enfermedad de Alzheimer , Células-Madre Neurales , Animales , Ratones , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Cisteína Endopeptidasas , Modelos Animales de Enfermedad , Ratones Transgénicos , Inhibidores de Cisteína Proteinasa
5.
Eur J Immunol ; 51(2): 393-407, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33029793

RESUMEN

Cytomegalovirus (CMV)-based vaccines show promising effects against chronic infections in nonhuman primates. Therefore, we examined the potential of hepatitis B virus (HBV) vaccines based on mouse CMV (MCMV) vectors expressing the small HBsAg. Immunological consequences of vaccine virus attenuation were addressed by either replacing the dispensable gene m157 ("MCMV-HBsȍ) or the gene M27 ("ΔM27-HBs"), the latter encodes a potent IFN antagonist targeting the transcription factor STAT2. M27 was chosen, since human CMV encodes an analogous gene product, which also induced proteasomal STAT2 degradation by exploiting Cullin RING ubiquitin ligases. Vaccinated mice were challenged with HBV through hydrodynamic injection. MCMV-HBs and ΔM27-HBs vaccination achieved accelerated HBV clearance in serum and liver as well as robust HBV-specific CD8+ T-cell responses. When we explored the therapeutic potential of MCMV-based vaccines, especially the combination of ΔM27-HBs prime and DNA boost vaccination resulted in increased intrahepatic HBs-specific CD8+ T-cell responses and HBV clearance in persistently infected mice. Our results demonstrated that vaccines based on a replication competent MCMV attenuated through the deletion of an IFN antagonist targeting STAT2 elicit robust anti-HBV immune responses and mediate HBV clearance in mice in prophylactic and therapeutic immunization regimes.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Muromegalovirus/inmunología , Animales , Antivirales/inmunología , Linfocitos T CD8-positivos/inmunología , Células Cultivadas , Femenino , Hepatitis B Crónica/virología , Inmunización/métodos , Interferones/inmunología , Hígado/inmunología , Hígado/virología , Masculino , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción STAT2/inmunología , Vacunación/métodos , Replicación Viral/inmunología
6.
Int J Syst Evol Microbiol ; 70(10): 5271-5279, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32833615

RESUMEN

A psychrotolerant actinobacterium, designated strain J5903T, was isolated from an alkaline soil sample from the rhizosphere of Suaeda salsa collected in desertification land surrounding Jiuliancheng Nur in Hebei Province, PR China. Cells of the isolate were Gram-stain-positive, aerobic, non-motile and non-spore-forming cocci. Strain J5903T grew optimally at 20‒25 °C, at pH 7.0‒7.5 and with <1 % (w/v) NaCl. The cell-wall peptidoglycan type was B2γ with d-2,4-diaminobutyric acid and l-2,4-diaminobutyric acid as diagnostic amino acids. The muramyl residue was acetyl type. The menaquinones were MK-11, MK-12, MK-10 and MK-13. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and one unidentified glycolipid. The major whole-cell fatty acids were anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The genomic DNA G+C content was 69.1 mol%. It shared the highest average nucleotide identity and digital DNA-DNA hybridization values with Planctomonas deserti 13S1-3T. Phylogenies based on genome sequence showed that strain J5903T and P. deserti 13S1-3T formed a robust cluster with high bootstrap support. Strain J5903T shared typical chemotaxonomic characteristics with P. deserti 13S1-3T. Combining the polyphasic taxonomic evidence, strain J5903T represents a novel species of the genus Planctomonas, for which the name Planctomonas psychrotolerans sp. nov. is proposed. The type strain is J5903T (=DSM 101894T=CGMCC 1.15523T).


Asunto(s)
Actinobacteria/clasificación , Chenopodiaceae/microbiología , Filogenia , Rizosfera , Microbiología del Suelo , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/química
7.
Int J Syst Evol Microbiol ; 70(7): 4179-4185, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32558636

RESUMEN

A novel moderately halophilic, filamentous actinobacterium, designated as XMNu-373T, was isolated from a saline-alkaline soil sample collected from the Mongolia Plateau, Dongwu County, Inner Mongolia Autonomous Region, PR China. The isolate grew optimally at 28‒37 °C, pH 7.0‒8.0 and with 2-5 % (w/v) NaCl. The substrate mycelia fragmented into rod-like elements, and the white aerial mycelia formed spore chains at maturity. The predominant menaquinone was MK-9(H4). The polar lipids were diphosphatidylglycerol, three unidentified phosphoglycolipids, an unidentified aminophospholipid, two phosphatidylinositol mannosides, four unidentified phospholipids, phosphatidylglycerol and two unidentified lipids. The major cellular fatty acids were iso-C16 : 0, anteiso-C17 : 0 and anteiso-C15 : 0. The genomic DNA G+C content was 66.2 mol%. It shared high 16S rRNA gene sequence similarities to Phytoactinopolyspora halotolerans YIM 96448T (96.1 %) and Phytoactinopolyspora endophytica EGI 60009T (96.0 %). Phylogenetic trees based on 16S rRNA gene sequences revealed that strain XMNu-373T resided in the clade of family Jiangellaceae, and it formed a monophyletic branch distinct from four other recognized type species in the subclade of the genus Phytoactinopolyspora. On the basis of polyphasic taxonomic evidence, strain XMNu-373T represents a novel species of the genus Phytoactinopolyspora, for which the name Phytoactinopolyspora mesophila sp. nov. is proposed. The type strain is XMNu-373T (=JCM 33740T=CGMCC 4.7654T).


Asunto(s)
Actinobacteria/clasificación , Álcalis , Filogenia , Salinidad , Microbiología del Suelo , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo/química , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
J Biochem Mol Toxicol ; 34(12): e22597, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32762018

RESUMEN

Ginsenoside Rh2 is a primary bioactive compound obtained from ginseng that indicated anticancer activities against several malignant tumors. However, previous studies have reported little about the inhibitory effect of Rh2 on osteosarcoma (OS). This study aims to explore whether Rh2 could exert anticancer effects in OS cells and further investigate the proliferation, migration, and apoptosis mechanisms induced by Rh2 in human OS U20S cell line. The viability of U20S cells was obtained by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cell migration property was analyzed by wound-healing assay. Apoptosis was visualized using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), 4',6-diamidino-2-phenylindole (DAPI), and annexin V/propidium iodide (PI) staining. Relative protein expressed was confirmed through Western blot analysis. Mitochondrial membrane potential was evaluated by JC-1 staining. In this study, we used broad-spectrum anticancer drug cisplatin (CP) as a positive control. The results indicated that Rh2 remarkably inhibited cell viability of U20S cells in a dose- and time-dependent manner, and suppressed migration. TUNEL, DAPI, annexin V/PI, and JC-1 assay suggested that Rh2 could induce cellular apoptosis. Rh2 could reduce the levels of Bcl-2, caspase 3, and caspase 9, and promote the expression level of Bax in U20S cells. Moreover, Rh2 could induce apoptosis by promoting mitogen-activated protein kinase (MAPK) signaling pathway and inhibit PI3K/Akt/mTOR and nuclear factor-κB (NF-κB) signaling pathway in U20S cells. These findings indicated that Rh2 has an anticancer effect on U20S cells by regulating MAPK, PI3K/Akt/mTOR, and NF-κB signaling pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ginsenósidos/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Osteosarcoma/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Línea Celular Tumoral , Humanos , Etiquetado Corte-Fin in Situ , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Osteosarcoma/enzimología , Osteosarcoma/patología
9.
Exp Cell Res ; 383(2): 111550, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31398350

RESUMEN

The development of hepatocellular carcinoma (HCC) is strongly associated with chronic inflammation. p66Shc is an oxidase previously shown to promote androgen-independent cell growth through generation of reactive oxygen species. However, the importance and biologic functions of p66Shc in HCC are unclear. The clinical significance of p66Shc was assessed in a large cohort of patients with HCC. High Shc1 expression was closely correlated with poor clinical outcomes and early recurrence of HCC. p66Shc expression was also determined in HCC samples and cell lines and found to be increased. Moreover, knockdown of p66Shc significantly inhibited cell proliferation, motility in vitro and tumor growth in vivo and could attenuate the proliferation, and motility of cells stimulated by activated macrophage conditioned media. Mechanically, p66Shc knockdown inhibited phosphorylation of STAT3 on serine 727 in vitro and in vivo. Our results show that high p66Shc expression in HCC predicts a worse prognosis for survival. Furthermore, p66Shc may serve as a novel candidate target for HCC therapy.


Asunto(s)
Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Factor de Transcripción STAT3/metabolismo , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/fisiología , Microambiente Tumoral/genética , Animales , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidad , Proliferación Celular/genética , Células Cultivadas , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidad , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Pronóstico , Transducción de Señal/genética , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/genética , Células THP-1
10.
J Hepatol ; 71(4): 685-698, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31173811

RESUMEN

BACKGROUND & AIMS: CD100 is constitutively expressed on T cells and can be cleaved from the cell surface by matrix metalloproteases (MMPs) to become soluble CD100 (sCD100). Both membrane-bound CD100 (mCD100) and sCD100 have important immune regulatory functions that promote immune cell activation and responses. This study investigated the expression and role of mCD100 and sCD100 in regulating antiviral immune responses during HBV infection. METHODS: mCD100 expression on T cells, sCD100 levels in the serum, and MMP expression in the liver and serum were analysed in patients with chronic HBV (CHB) and in HBV-replicating mice. The ability of sCD100 to mediate antigen-presenting cell maturation, HBV-specific T cell activation, and HBV clearance were analysed in HBV-replicating mice and patients with CHB. RESULTS: Patients with CHB had higher mCD100 expression on T cells and lower serum sCD100 levels compared with healthy controls. Therapeutic sCD100 treatment resulted in the activation of DCs and liver sinusoidal endothelial cells, enhanced HBV-specific CD8 T cell responses, and accelerated HBV clearance, whereas blockade of its receptor CD72 attenuated the intrahepatic anti-HBV CD8 T cell response. Together with MMP9, MMP2 mediated mCD100 shedding from the T cell surface. Patients with CHB had significantly lower serum MMP2 levels, which positively correlated with serum sCD100 levels, compared with healthy controls. Inhibition of MMP2/9 activity resulted in an attenuated anti-HBV T cell response and delayed HBV clearance in mice. CONCLUSIONS: MMP2/9-mediated sCD100 release has an important role in regulating intrahepatic anti-HBV CD8 T cell responses, thus mediating subsequent viral clearance during HBV infection. LAY SUMMARY: Chronic hepatitis B virus (HBV) infection is a major public health problem worldwide. The clearance of HBV relies largely on an effective T cell immune response, which usually becomes dysregulated in chronic HBV infection. Our study provides a new mechanism to elucidate HBV persistence and a new target for developing immunotherapy strategies in patients chronically infected with HBV.


Asunto(s)
Antígenos CD , Linfocitos T CD8-positivos/inmunología , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica , Inmunidad Celular/inmunología , Hígado , Metaloproteinasa 2 de la Matriz/inmunología , Metaloproteinasa 9 de la Matriz/inmunología , Semaforinas , Animales , Antígenos CD/sangre , Antígenos CD/inmunología , Perfilación de la Expresión Génica , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Humanos , Hígado/inmunología , Hígado/virología , Activación de Linfocitos/inmunología , Ratones , Semaforinas/sangre , Semaforinas/inmunología
11.
J Viral Hepat ; 26(1): 73-82, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30260541

RESUMEN

Adaptation of hepatitis C virus (HCV) to CD8+ T cell selection pressure is well described; however, it is unclear if HCV differentially adapts in different populations. Here, we studied HLA class I-associated viral sequence polymorphisms in HCV 1b isolates in a Chinese population and compared viral substitution patterns between Chinese and German populations. We identified three HLA class I-restricted epitopes in HCV NS3 with statistical support for selection pressure and found evidence for differential escape pathways between isolates from China and Germany depending on the HLA class I molecule. The substitution patterns particularly differed in the epitope VTLTHPITK1635-1643 , which was presented by HLA-A*03 as well as HLA-A*11, two alleles with highly different frequencies in the two populations. In Germany, a substitution in position seven of the epitope was the most frequent substitution in the presence of HLA-A*03, functionally associated with immune escape and nearly absent in Chinese isolates. In contrast, the most frequent substitution in China was located at position two of the epitope and became the predominant consensus residue. Moreover, substitutions in position one of the epitope were significantly enriched in HLA-A*11-positive individuals in China and associated with different patterns of CD8+ T cell reactivity. Our study confirms the differential escape pathways selected by HCV that depended on different HLA class I alleles in Chinese and German populations, indicating that HCV differentially adapts to distinct HLA class I alleles in these populations. This result has important implications for vaccine design against highly variable and globally distributed pathogens, which may require matching antigen sequences to geographic regions for T cell-based vaccine strategies.


Asunto(s)
Presentación de Antígeno , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/genética , Antígenos HLA-A/inmunología , Hepacivirus/genética , Proteínas no Estructurales Virales/genética , Alelos , China , Epítopos de Linfocito T/inmunología , Alemania , Antígenos HLA-A/genética , Antígeno HLA-A11/genética , Antígeno HLA-A11/inmunología , Antígeno HLA-A3/genética , Antígeno HLA-A3/inmunología , Hepacivirus/inmunología , Hepatitis C/etnología , Hepatitis C/inmunología , Humanos , Evasión Inmune , Mutación , Selección Genética , Proteínas no Estructurales Virales/inmunología
12.
Cell Physiol Biochem ; 36(3): 1223-36, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26138883

RESUMEN

BACKGROUND/AIMS: Anoikis resistance is a prerequisite for hepatocellular carcinoma (HCC) metastasis. The role of Caveolin-1 (CAV1) in anoikis resistance of HCC remains unclear. METHODS: The oncogenic effect of CAV1 on anchor-independent growth and anoikis resistance was investigated by overexpression and knockdown of CAV1 in hepatoma cells. IGF-1 pathway and its downstream signals were detected by immunoblot analysis. Caveolae invagination and IGF-1R internalization was studied by electron microscopy and (125)I-IGF1 internalization assay, respectively. The role of IGF-1R and tyrosine-14 residue (Y-14) of CAV1 was explored by deletion experiment and mutation experiment, respectively. The correlation of CAV1 and IGF-1R was further examined by immunochemical analysis in 120 HCC specimens. RESULTS: CAV1 could promote anchor-independent growth and anoikis resistance in hepatoma cells. CAV1-overexpression increased the expression of IGF-1R and subsequently activated PI3K/Akt and RAF/MEK/ERK pathway, while CAV1 knockdown showed the opposite effect. The mechanism study revealed that CAV1 facilitated caveolae invagination and (125)I-IGF1 internalization. IGF-1R deletion or Y-14 mutation reversed CAV1 mediated anchor-independent growth and anoikis resistance. In addition, CAV1 expression was positively related to IGF-1R expression in human HCC tissues. CONCLUSION: CAV1 confers resistance of hepatoma cells to anoikis by activating IGF-1 pathway, providing a potential therapeutic target for HCC metastasis.


Asunto(s)
Anoicis/genética , Carcinoma Hepatocelular/genética , Caveolina 1/genética , Regulación Neoplásica de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/genética , Neoplasias Hepáticas/genética , Receptor IGF Tipo 1/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Caveolas/metabolismo , Caveolas/patología , Caveolina 1/agonistas , Caveolina 1/antagonistas & inhibidores , Caveolina 1/metabolismo , Adhesión Celular , Línea Celular Tumoral , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Quinasas Quinasa Quinasa PAM/genética , Quinasas Quinasa Quinasa PAM/metabolismo , Mutación , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor IGF Tipo 1/metabolismo , Transducción de Señal , Análisis de Supervivencia , Quinasas raf/genética , Quinasas raf/metabolismo
13.
RMD Open ; 10(1)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233074

RESUMEN

BACKGROUND: Indeterminate readout of the quantitative interferon-γ release test (QFT) for Mycobacterium tuberculosis screening is a specific laboratory finding for systemic lupus erythematosus (SLE), which may be due to T-cell exhaustion and abnormal programmed death receptor 1 (PD-1)/programmed death-ligand 1 (PD-L1) signalling. METHODS: We enrolled 104 patients with SLE and 225 with other rheumatic musculoskeletal diseases (RMDs) who presented to the outpatient clinic between 2020 and 2023. Twenty healthy donors served as the controls. The QFT was performed in all participants, and those with indeterminate results were compared among the groups. Immunophenotyping and functional assays were performed using blood mononuclear cells. Interferon (IFN)-γ was detected in vitro and ex vivo in patients with SLE with indeterminate or negative QFT results, before or after rituximab therapy. RESULTS: 104 patients with SLE had a significantly higher rate of indeterminate QFT results was significantly higher (17.31%) than that of 225 patients with RMD (3.56%). Patients with SLE with indeterminate QFT had more active disease (SLEDAI-2K, mean 10.94 vs 4.02, p<0.0001), including a higher incidence of active nephritis (55.56% vs 29.07%). Indeterminate QFT in SLE is mainly caused by an insufficient IFN-γ response in CD8+T cells with exhausted immunophenotypes. The abnormal interaction between exhausted PD-1 high CD8+ T cells and activated PD-L1 low memory B cells in SLE can be reversed with a PD-1 agonist or increased PD-L1 expression. Rituximab treatment indirectly reversed this IFN-γ response. CONCLUSION: The PD-1/PD-L1 signalling pathway, which governs the crosstalk between exhausted CD8+ T cells and activated memory B cells, is a mechanistic explanation for insufficient interferon-γ response in patients with SLE.


Asunto(s)
Linfocitos T CD8-positivos , Lupus Eritematoso Sistémico , Humanos , Linfocitos T CD8-positivos/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Células B de Memoria , Antígeno B7-H1/fisiología , Ligandos , Rituximab , Lupus Eritematoso Sistémico/complicaciones
14.
J Huazhong Univ Sci Technolog Med Sci ; 33(3): 392-397, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23771666

RESUMEN

The type I interferon and IFNAR play an important role in hepatitis B virus (HBV) infection and anti-HBV therapy. However, its mechanism of action is still poorly understood. To gain more insights into the role of type I interferon and type I interferon receptor (IFNAR) in HBV infection, we established an HBV persistent replication IFNAR knockout (IFNAR(-/-)) mouse model and preliminarily applied this model. At first, the progeny of IFNAR(-/-) mouse was reproduced. Then hydrodynamic injection with pAAV/HBV1.2 plasmid was conducted to establish the persistent HBV replication IFNAR(-/-) mouse model. At last, we applied this model to evaluate the effect of nucleoside analogues entecavir (ETV) on HBV replication. It was found that there was no difference in the serum HBsAg and HBeAg levels and HBcAg expression in the liver tissue between the ETV treated groups and normal saline (NS) treated group, but the serum HBV DNA levels were significantly suppressed 10, 25, 40 and 55 days after the ETV treatment [P=0.035, P=0.00, P=0.149 and P=0.084, IFNAR knockout (KO) control group vs. C57BL/6 ETV groups, respectively; P=0.081, P=0.001, P=0.243 and P=0.147, IFNAR KO control group vs. IFNAR KO ETV groups, respectively]. Interestingly, there was no difference in serum HBV DNA levels between the ETV treated IFNAR(-/-) and C57BL/6 mice. This result suggests that HBV suppression during ETV treatments doesn't depend on type I interferon and IFNAR. Collectively, persistent HBV replication IFNAR(-/-) mouse model that we established is a useful and convenient tool to detect the function of the type I interferon and IFNAR in HBV infection and anti-HBV treatments.


Asunto(s)
Modelos Animales de Enfermedad , Virus de la Hepatitis B/fisiología , Hepatitis B/genética , Hepatitis B/virología , Receptor de Interferón alfa y beta/metabolismo , Replicación Viral/genética , Animales , Enfermedad Crónica , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor de Interferón alfa y beta/genética
15.
ACS Pharmacol Transl Sci ; 6(7): 925-942, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37470012

RESUMEN

The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19) has significantly altered people's way of life. Despite widespread knowledge of vaccination, mask use, and avoidance of close contact, COVID-19 is still spreading around the world. Numerous research teams are examining the SARS-CoV-2 infection process to discover strategies to identify, prevent, and treat COVID-19 to limit the spread of this chronic coronavirus illness and restore lives to normalcy. Nanobodies have advantages over polyclonal and monoclonal antibodies (Ab) and Ab fragments, including reduced size, high stability, simplicity in manufacture, compatibility with genetic engineering methods, and lack of solubility and aggregation issues. Recent studies have shown that nanobodies that target the SARS-CoV-2 receptor-binding domain and disrupt ACE2 interactions are helpful in the prevention and treatment of SARS-CoV-2-infected animal models, despite the lack of evidence in human patients. The creation and evaluation of nanobodies, as well as their diagnostic and therapeutic applications against COVID-19, are discussed in this paper.

16.
J Clin Med ; 12(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902786

RESUMEN

Chronic hepatitis B virus (HBV) infection continues to be a global public health burden. B cells play a pivotal role in mediating HBV clearance and can participate in the development of anti-HBV adaptive immune responses through multiple mechanisms, such as antibody production, antigen presentation, and immune regulation. However, B cell phenotypic and functional disorders are frequently observed during chronic HBV infection, suggesting the necessity of targeting the disordered anti-HBV B cell responses to design and test new immune therapeutic strategies for the treatment of chronic HBV infection. In this review, we provide a comprehensive summary of the multiple roles of B cells in mediating HBV clearance and pathogenesis as well as the latest developments in understanding the immune dysfunction of B cells in chronic HBV infection. Additionally, we discuss novel immune therapeutic strategies that aim to enhance anti-HBV B cell responses for curing chronic HBV infection.

17.
Phytomedicine ; 115: 154826, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37167846

RESUMEN

BACKGROUND: Chronic non-atrophic gastritis (CNG) is the most common type of chronic gastritis. If not actively treated, it may induce gastric cancer (GC). Western medicine is effective in CNG, but there are more adverse reactions after long-term medication, and it is easy to relapse after treatment, which affects patients' health and life. Tibetan medicine Liuwei Muxiang Pills (LWMX pills) is a traditional Tibetan medicine compound, which has a unique curative effect in the treatment of gastric inflammation, especially chronic non-atrophic gastritis. However, the mechanisms of LWMX pills for treatment CNG still remain poor known. PURPOSE: The aim of this study was to evaluate the therapeutic intervention potential of Tibetan medicine LWMX pills on CNG and explore its potential mechanisms in mice models. METHODS: The mice models was established to evaluate the therapeutic effect of LWMX pills on CNG. The main components of LWMX pills were analyzed by GC-MS. HE staining, immunohistochemistry, proteomics and Western Blot were used to analyze the potential mechanism of LWMX pills for CNG treatment. RESULTS: In the present study, LWMX pills containing costunolide, dehydrocostuslactone and antioxidants were found. IF results showed that the expression of ALDH1B1 in the control group was significantly lower than that in the model group in the gastric mucosa tissue, and the expression of ALDH1B1 was significantly lower in the 25 mg/ml LWMX Pills group (one month) and 25 mg/ml LWMX Pills group (two months) than in the model group. IHC revealed that model group samples expressed higher levels of Furin than 25 mg/ml LWMX Pills group samples, as evidenced by very strong staining of Furin in gastric mucosal cells. However, AMY2 staining in gastric mucosal cells did not differ significantly between the treated and control groups. the protein expression levels of these proteins were decreased in 25 mg/mL LWMX pills. Meanwhile, we found that the CAM1 protein expression in the in 25 mg/ml LWMX pills group (two mouths) was increased compared to the in 25 mg/ml LWMX pills group (one mouths).Western blotting showed that the protein expression levels of Furin, AMY2A, CPA3, ALDH1B1, Cam1, COXII, IL-6, IL-1ß were decreased in 25 mg/mL LWMX pills. Meanwhile, that the CAM1 protein expression in the in 25 mg/ml LWMX pills group (two mouths) was increased compared to the in 25 mg/ml LWMX pills group (one mouths). CONCLUSION: 25mg/ml LWMX pill treatment for one month had better therapeutic effect on mice CNG. Further proteomic results showed that LWMX pills maintain gastric function by inhibiting inflammation and oxidative stress, and we also found that LWMX pills regulate the expression of proteins associated with cancer development (Amy2, Furin).


Asunto(s)
Gastritis Atrófica , Gastritis , Ratones , Animales , Medicina Tradicional Tibetana/métodos , Furina , Proteómica , Recurrencia Local de Neoplasia , Gastritis Atrófica/tratamiento farmacológico , Gastritis/inducido químicamente , Gastritis/tratamiento farmacológico , Mucosa Gástrica/metabolismo , Inflamación
18.
Virol Sin ; 38(4): 606-619, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37414153

RESUMEN

A key question in the coronavirus disease 2019 (COVID-19) pandemic is the duration of specific T cell responses against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) post primary infection, which is difficult to address due to the large-scale COVID-19 vaccination and re-exposure to the virus. Here, we conducted an analysis of the long-term SARS-CoV-2-specific T cell responses in a unique cohort of convalescent individuals (CIs) that were among the first to be infected worldwide and without any possible antigen re-exposure since then. The magnitude and breadth of SARS-CoV-2-specific T cell responses correlated inversely with the time that had elapsed from disease onset and the age of those CIs. The mean magnitude of SARS-CoV-2-specific CD4 and CD8 T cell responses decreased about 82% and 76%, respectively, over the time period of ten months after infection. Accordingly, the longitudinal analysis also demonstrated that SARS-CoV-2-specific T cell responses waned significantly in 75% of CIs during the follow-up. Collectively, we provide a comprehensive characterization of the long-term memory T cell response in CIs, suggesting that robust SARS-CoV-2-specific T cell immunity post primary infection may be less durable than previously expected.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Vacunas contra la COVID-19 , Linfocitos T CD8-positivos , Anticuerpos Antivirales
19.
Cell Mol Neurobiol ; 32(8): 1275-85, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22618532

RESUMEN

Hypoxia-induced retinal ganglion cell (RGC) death has been proposed to be the critical event in the pathophysiology of glaucoma. Therefore, delaying or halting RGC degeneration, known as neuroprotection, is a novel and promising approach with potential clinical applications for treating glaucoma. In this study, we investigate hypoxia-induced cell death of RGCs and the underlying mechanisms of N-acetylcysteine (NAC) as a neuroprotectant. To establish a model for chemical hypoxia-induced cell death, RGC-5 cells were treated with the hypoxia mimetic cobalt chloride (CoCl2). Following CoCl2 exposure, significant levels of apoptotic and autophagic cell death were observed in RGC-5 cells, evidenced by lysosome dysfunction and autophagosome formation. Pretreating RGC-5 cells with NAC significantly counteracted the autophagic cell death. NAC-mediated neuroprotection was attributed to the direct scavenging of reactive oxygen species and was mediated by targeting the hypoxia-inducible factor-1α pathway via the BNIP3 and PI3K/Akt/mTOR pathways. These results provide insights into the degeneration of RGCs and present a potential clinical application for NAC as a neuroprotectant.


Asunto(s)
Acetilcisteína/administración & dosificación , Autofagia/fisiología , Sistemas de Liberación de Medicamentos , Subunidad alfa del Factor 1 Inducible por Hipoxia/biosíntesis , Fármacos Neuroprotectores/administración & dosificación , Células Ganglionares de la Retina/metabolismo , Animales , Animales Recién Nacidos , Autofagia/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Línea Celular , Línea Celular Transformada , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Cobalto/toxicidad , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos/métodos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Células Ganglionares de la Retina/efectos de los fármacos
20.
Zhonghua Gan Zang Bing Za Zhi ; 20(10): 794-7, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23207344

RESUMEN

OBJECTIVE: To explore the mitochondrial toxicities induced by zidovudine (AZT) and adefovir dipivoxil (ADV) antiviral drugs using a rat model system. METHODS: Twelve healthy Sprague-Dawley rats were randomly divided into three equal groups and treated by oral gavage with zidovudine (125 mg/kg/day), adefovir (40 mg/kg/day), or saline (equal volume) for 28 days. The rats' body weights were measured once a week, and blood was collected every two weeks for blood and biochemical tests. All animals were sacrificed at the end of treatment, and liver, kidney, skeletal muscle, and cardiac muscle were collected by necropsy. Mitochondria were isolated from the respective tissue samples, and the activities of respiratory chain complexes were measured. DNA was purified from each sample and the mitochondrial DNA (mtDNA) content was monitored by quantitative real time PCR. Mitochondrial morphology was analyzed under electron microscope. RESULTS: No significant adverse effects, including body weight loss, abnormal blood or biochemistry, were observed in rats treated with AZT or ADV. The activities of mitochondrial cytochrome c oxidase in liver and cardiac muscle were slightly decreased in rats treated with AZT (liver: 9.44+/-3.09 vs. 17.8+/-12.38, P?=?0.21; cardiac muscle: 32.74+/-5.52 vs. 24.74+/-20.59, P?=?0.28; kidney: 4.42+/-1.53 vs. 14.45+/-13.75, P?=?0.18; skeletal muscle: 33.75+/-8.74 vs. 40.04+/-2.49, P?=?0.45). The mtDNA content was significantly decreased in cardiac muscle of AZT-treated rats (cardiac muscle: 0.15+/-0.13 vs. 0.32+/-0.42, P?=?0.85). The morphology of mitochondria in liver, kidney, skeletal muscle, and cardiac muscle was significantly altered in the AZT-treated rats and included disappearance of the outer membrane, severely damaged structure, and swollen or completely absent cristae. No obvious effects were noted in the ADV- or saline-treated rats. CONCLUSION: Significant adverse effects related to mitochondrial toxicity were observed in rats treated with AZT. The slightly decreased mtDNA content in ADV-treated rats may suggest that this antiviral drug can also cause mitochondrial toxic effects.


Asunto(s)
Adenina/análogos & derivados , Mitocondrias/efectos de los fármacos , Organofosfonatos/efectos adversos , Zidovudina/efectos adversos , Adenina/efectos adversos , Animales , ADN Mitocondrial/efectos de los fármacos , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Riñón/enzimología , Hígado/enzimología , Mitocondrias/metabolismo , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Musculares/efectos de los fármacos , Músculo Esquelético/enzimología , Miocardio/enzimología , Ratas , Ratas Sprague-Dawley
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