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1.
EMBO J ; 40(18): e108249, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34296442

RESUMO

SARS-CoV-2 is an emerging coronavirus that causes dysfunctions in multiple human cells and tissues. Studies have looked at the entry of SARS-CoV-2 into host cells mediated by the viral spike protein and human receptor ACE2. However, less is known about the cellular immune responses triggered by SARS-CoV-2 viral proteins. Here, we show that the nucleocapsid of SARS-CoV-2 inhibits host pyroptosis by blocking Gasdermin D (GSDMD) cleavage. SARS-CoV-2-infected monocytes show enhanced cellular interleukin-1ß (IL-1ß) expression, but reduced IL-1ß secretion. While SARS-CoV-2 infection promotes activation of the NLRP3 inflammasome and caspase-1, GSDMD cleavage and pyroptosis are inhibited in infected human monocytes. SARS-CoV-2 nucleocapsid protein associates with GSDMD in cells and inhibits GSDMD cleavage in vitro and in vivo. The nucleocapsid binds the GSDMD linker region and hinders GSDMD processing by caspase-1. These insights into how SARS-CoV-2 antagonizes cellular inflammatory responses may open new avenues for treating COVID-19 in the future.


Assuntos
COVID-19/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Nucleocapsídeo/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/fisiologia , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Caspase 1/imunologia , Caspase 1/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Camundongos , Monócitos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Ligação a Fosfato/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Células THP-1
2.
Small ; : e2307365, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990372

RESUMO

In search of effective therapeutics for breast cancers, establishing physiologically relevant in vitro models is of great benefit to facilitate the clinical translation. Despite extensive progresses, it remains to develop the tumor models maximally recapturing the key pathophysiological attributes of their native counterparts. Therefore, the current study aimed to develop a microsphere-enabled modular approach toward the formation of in vitro breast tumor models with the capability of incorporating various selected cells while retaining spatial organization. Poly (lactic-co-glycolic acid) microspheres (150-200 mm) with tailorable pore size and surface topography are fabricated and used as carriers to respectively lade with breast tumor-associated cells. Culture of cell-laden microspheres assembled within a customized microfluidic chamber allowed to form 3D tumor models with spatially controlled cell distribution. The introduction of endothelial cell-laden microspheres into cancer-cell laden microspheres at different ratios would induce angiogenesis within the culture to yield vascularized tumor. Evaluation of anticancer drugs such as doxorubicin and Cediranib on the tumor models do demonstrate corresponding physiological responses. Clearly, with the ability to modulate microsphere morphology, cell composition and spatial distribution, microsphere-enabled 3D tumor tissue formation offers a high flexibility to satisfy the needs for pathophysiological study, anticancer drug screening or design of personalized treatment.

3.
Protein Expr Purif ; 165: 105482, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31470095

RESUMO

Trehalase catalyzes the conversion of one molecule of trehalose into two glucose molecules. The trehalase TreM from thermophilic fungus Myceliophthora sepedonium was expressed in Aspergillus niger via traditional homologous recombination with trehalase activity of 406.44 U/mL. The multi-copy knock-in expression strategy mediated by the CRISPR/Cas9 tool was used to improve the production of the TreM trehalase in Aspergillus niger, which was up to 1943.06 U/mL with a low-background of secreted proteins, 4.8-fold than the transformant obtained via the traditional method. The highest recombinant trehalase activity of the shake fermentation supernatant achieved 4268.29 U/mL when 1.5% glucose was added. Activity assaying showed that the recombinant TreM possessed a specific activity of 679.09 U/mg after gel filtration chromatography purification. The recombinant TreM displayed optimal activity at pH 5.6 and 60 °C and exhibited prominent stability under the conditions of 45-50 °C and pH 4.0-7.5. The activity of recombinant TreM was strongly enhanced by Co2+ (1, 5 mM), Cu2+ (1 mM), Mn2+ (1, 5 mM) and ATP (5 mM), and was greatly inhibited by Cu2+ (10 mM), EDTA (10 mM) and SDS (10 mM).


Assuntos
Ascomicetos/genética , Aspergillus niger/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Trealase/química , Trealase/genética , Sistemas CRISPR-Cas , Cromatografia em Gel , Estabilidade Enzimática , Fermentação , Expressão Gênica , Temperatura Alta , Concentração de Íons de Hidrogênio , Análise de Sequência de Proteína , Transfecção
4.
Protein Expr Purif ; 167: 105544, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31759085

RESUMO

Leucine aminopeptidase (LAP), an exopeptidase that releases amino acid residues, especially leucine, from the N-terminus of polypeptides, is often applied to debitter protein hydrolysate in the food industry. However, there are no thermostable and high activity enzymes that can be used in the food industry. In this study, we obtained the highly active and thermostable leucine aminopeptidases screened from the thermophilic fungi Thermomyces lanuginosus, Talaromyces thermophilus, and Malbranchea cinnamomea. The activity of the recombinant leucine aminopeptidase Thelap was significantly increased to 2771.5 U/mL, as mediated by the CRISPR/Cas9 tool. The recombinant Thelap was easily purified from fermentation broth by Ni-affinity chromatography, and the specific activity of the purified Thelap was increased to 7449.6 U/mg. The recombinant Thelap showed optimal activity at pH 8.5 and 75 °C and remained above 70% of the maximum activity over a wide temperature range (30-80 °C). With regard to temperature stability, Thelap retained more than 90% activity when it was incubated at 65-75 °C for 2 h. K+ and Co2+ increased the enzyme activity of the recombinant Thelap, while Ba2+, Mn2+, Ni2+, Ca2+, Mg2+ and SDS inhibited its enzyme activity, and the inhibition capacity of Mg2+ was the weakest. Upon application in soy protein hydrolysis, Thelap could significantly increase the degree of hydrolysis and remove more hydrophobic amino acids from the N-terminal region of the polypeptide to decrease the bitterness.


Assuntos
Eurotiales/metabolismo , Leucil Aminopeptidase/biossíntese , Aspergillus niger/genética , Fermentação , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Expressão Gênica , Leucil Aminopeptidase/química , Leucil Aminopeptidase/metabolismo , Proteínas Recombinantes , Proteínas de Soja/metabolismo
5.
J Ind Microbiol Biotechnol ; 47(1): 133-144, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31786675

RESUMO

Trehalase catalyzes the hydrolysis of the non-reducing disaccharide trehalose. The highly active trehalase MthT from Myceliophthora thermophila was screened from the trehalase genes of six species of filamentous fungi. An ingenious multi-copy knock-in expression strategy mediated by the CRISPR/Cas9 tool and medium optimization were used to improve MthT production in Aspergillus niger, up to 1698.83 U/mL. The protein background was dramatically abated due to insertion. The recombinant MthT showed optimal activity at pH 5.5 and 60 °C, and exhibited prominent thermal stability between 50 and 60 °C under acid conditions (pH 4.5-6.5). The ethanol conversion rate (ethanol yield/total glucose) was significantly improved by addition of MthT (51.88%) compared with MthT absence (34.38%), using 30% starch saccharification liquid. The results of this study provided an effective strategy, established a convenient platform for heterologous expression in A. niger and showed a potential strategy to decrease production costs in industrial ethanol production.


Assuntos
Aspergillus niger/metabolismo , Etanol/metabolismo , Sordariales/metabolismo , Trealase/metabolismo , Aspergillus niger/genética , Sistemas CRISPR-Cas , Estabilidade Enzimática , Fermentação , Temperatura Alta , Sordariales/genética , Trealase/genética
6.
Proc Natl Acad Sci U S A ; 114(5): E820-E829, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28096400

RESUMO

Mesenchymal stromal stem cells (MSCs) isolated from adult tissues offer tangible potential for regenerative medicine, given their feasibility for autologous transplantation. MSC research shows encouraging results in experimental stroke, amyotrophic lateral sclerosis, and neurotrauma models. However, further translational progress has been hampered by poor MSC graft survival, jeopardizing cellular and molecular bases for neural repair in vivo. We have devised an adult human bone marrow MSC (hMSC) delivery formula by investigating molecular events involving hMSCs incorporated in a uniquely designed poly(lactic-co-glycolic) acid scaffold, a clinically safe polymer, following inflammatory exposures in a dorsal root ganglion organotypic coculture system. Also, in rat T9-T10 hemisection spinal cord injury (SCI), we demonstrated that the tailored scaffolding maintained hMSC stemness, engraftment, and led to robust motosensory improvement, neuropathic pain and tissue damage mitigation, and myelin preservation. The scaffolded nontransdifferentiated hMSCs exerted multimodal effects of neurotrophism, angiogenesis, neurogenesis, antiautoimmunity, and antiinflammation. Hindlimb locomotion was restored by reestablished integrity of submidbrain circuits of serotonergic reticulospinal innervation at lumbar levels, the propriospinal projection network, neuromuscular junction, and central pattern generator, providing a platform for investigating molecular events underlying the repair impact of nondifferentiated hMSCs. Our approach enabled investigation of recovery neurobiology components for injured adult mammalian spinal cord that are different from those involved in normal neural function. The uncovered neural circuits and their molecular and cellular targets offer a biological underpinning for development of clinical rehabilitation therapies to treat disabilities and complications of SCI.


Assuntos
Transplante de Células-Tronco Mesenquimais , Traumatismos da Medula Espinal/terapia , Adulto , Animais , Técnicas de Cocultura , Feminino , Gânglios Espinais , Membro Posterior , Humanos , Ácido Láctico , Lipopolissacarídeos , Locomoção , Masculino , Células-Tronco Mesenquimais , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Alicerces Teciduais
7.
Proc Natl Acad Sci U S A ; 114(30): E6147-E6156, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28696296

RESUMO

Brain tumor-initiating cells (BTICs) have been identified as key contributors to therapy resistance, recurrence, and progression of diffuse gliomas, particularly glioblastoma (GBM). BTICs are elusive therapeutic targets that reside across the blood-brain barrier, underscoring the urgent need to develop novel therapeutic strategies. Additionally, intratumoral heterogeneity and adaptations to therapeutic pressure by BTICs impede the discovery of effective anti-BTIC therapies and limit the efficacy of individual gene targeting. Recent discoveries in the genetic and epigenetic determinants of BTIC tumorigenesis offer novel opportunities for RNAi-mediated targeting of BTICs. Here we show that BTIC growth arrest in vitro and in vivo is accomplished via concurrent siRNA knockdown of four transcription factors (SOX2, OLIG2, SALL2, and POU3F2) that drive the proneural BTIC phenotype delivered by multiplexed siRNA encapsulation in the lipopolymeric nanoparticle 7C1. Importantly, we demonstrate that 7C1 nano-encapsulation of multiplexed RNAi is a viable BTIC-targeting strategy when delivered directly in vivo in an established mouse brain tumor. Therapeutic potential was most evident via a convection-enhanced delivery method, which shows significant extension of median survival in two patient-derived BTIC xenograft mouse models of GBM. Our study suggests that there is potential advantage in multiplexed targeting strategies for BTICs and establishes a flexible nonviral gene therapy platform with the capacity to channel multiplexed RNAi schemes to address the challenges posed by tumor heterogeneity.


Assuntos
Glioblastoma/patologia , Nanopartículas/uso terapêutico , Interferência de RNA , Animais , Carcinogênese/genética , Resistencia a Medicamentos Antineoplásicos , Feminino , Terapia Genética/métodos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Neuroradiology ; 59(11): 1083-1092, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28887618

RESUMO

PURPOSE: This meta-analysis is to comprehensively evaluate the diagnostic performance of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) for detecting intracranial aneurysm (IA). METHODS: PubMed, Embase, Web of Science, and the Cochrane library were systematically searched for retrieving eligible studies. Study inclusion, data extraction, and risk of bias assessment were performed by two researchers independently. Pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated to assess the diagnostic value. In addition, heterogeneity and subgroup analysis were carried out. RESULTS: In total, 18 studies comprising 3463 patients were selected. The results of 3D-TOF-MRA for diagnosing IA were SEN 0.89 (95% CI 0.82-0.94), SPE 0.94 (0.86-0.97), PLR 13.79 (5.92-32.12), NLR 0.11 (0.07-0.19), DOR 121.90 (38.81-382.94), and AUC 0.96 (0.94-0.98), respectively. In the subgroup analysis, studies without subarachnoid hemorrhage (SAH) tend to perform statistical significantly better (P < 0.05) in detecting IAs than studies with SAH 0.99 (0.98-1.00) vs. 0.89 (0.86-0.91). The diagnostic value of studies with a two-image reconstruction method was higher than studies with only one image reconstruction method: 0.99 (0.98-1.00) vs. 0.91 (0.89-0.94) with P < 0.05. The 3D-TOF-MRA had better SEN in aneurysms > 3 mm than the aneurysms ≤ 3 mm in diameter: 0.89 (0.87-0.92) vs. 0.78 (0.71-0.84) with P < 0.05. CONCLUSION: This study demonstrated that 3D-TOF-MRA has an excellent diagnostic performance for the overall assessment of IA and may serve as an alternative for further patient management with IA.


Assuntos
Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Diagnóstico Diferencial , Humanos
9.
Glia ; 64(6): 1034-49, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27018061

RESUMO

Edema in the central nervous system can rapidly result in life-threatening complications. Vasogenic edema is clinically manageable, but there is no established medical treatment for cytotoxic edema, which affects astrocytes and is a primary trigger of acute post-traumatic neuronal death. To test the hypothesis that adrenergic receptor agonists, including the stress stimulus epinephrine protects neural parenchyma from damage, we characterized its effects on hypotonicity-induced cellular edema in cortical astrocytes by in vivo and in vitro imaging. After epinephrine administration, hypotonicity-induced swelling of astrocytes was markedly reduced and cytosolic 3'-5'-cyclic adenosine monophosphate (cAMP) was increased, as shown by a fluorescence resonance energy transfer nanosensor. Although, the kinetics of epinephrine-induced cAMP signaling was slowed in primary cortical astrocytes exposed to hypotonicity, the swelling reduction by epinephrine was associated with an attenuated hypotonicity-induced cytosolic Ca(2+) excitability, which may be the key to prevent astrocyte swelling. Furthermore, in a rat model of spinal cord injury, epinephrine applied locally markedly reduced neural edema around the contusion epicenter. These findings reveal new targets for the treatment of cellular edema in the central nervous system.


Assuntos
Astrócitos/efeitos dos fármacos , Edema Encefálico/etiologia , Lesões Encefálicas/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , Adrenérgicos/farmacologia , Animais , Astrócitos/citologia , Lesões Encefálicas/complicações , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Ratos
10.
Stem Cells ; 33(10): 2985-94, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26260958

RESUMO

The treatment of human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer has been revolutionized by trastuzumab. However, longer survival of these patients now predisposes them to forming HER2 positive brain metastases, as the therapeutic antibodies cannot cross the blood brain barrier. The current oncologic repertoire does not offer a rational, nontoxic targeted therapy for brain metastases. In this study, we used an established human neural stem cell line, HB1.F3 NSCs and generated a stable pool of cells secreting a high amount of functional full-length anti-HER2 antibody, equivalent to trastuzumab. Anti-HER2Ab secreted by the NSCs (HER2Ab-NSCs) specifically binds to HER2 overexpressing human breast cancer cells and inhibits PI3K-Akt signaling. This translates to HER2Ab-NSC inhibition of breast cancer cell growth in vitro. Preclinical in vivo experiments using HER2Ab overexpressing NSCs in a breast cancer brain metastases (BCBM) mouse model demonstrate that intracranial injection of HER2Ab-NSCs significantly improves survival. In effect, these NSCs provide tumor localized production of HER2Ab, minimizing any potential off-target side effects. Our results establish HER2Ab-NSCs as a novel, nontoxic, and rational therapeutic approach for the successful treatment of HER2 overexpressing BCBM, which now warrants further preclinical and clinical investigation.


Assuntos
Anticorpos Anti-Idiotípicos/biossíntese , Neoplasias Encefálicas/terapia , Neoplasias da Mama/tratamento farmacológico , Células-Tronco Neurais/metabolismo , Receptor ErbB-2/biossíntese , Animais , Anticorpos Anti-Idiotípicos/imunologia , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Células-Tronco Neurais/imunologia , Células-Tronco Neurais/transplante , Receptor ErbB-2/imunologia , Trastuzumab/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Pharm ; 13(6): 1843-54, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27169484

RESUMO

As therapies continue to increase the lifespan of patients with breast cancer, the incidence of brain metastases has steadily increased, affecting a significant number of patients with metastatic disease. However, a major barrier toward treating these lesions is the inability of therapeutics to penetrate into the central nervous system and accumulate within intracranial tumor sites. In this study, we designed a cell-penetrating gold nanoparticle platform to increase drug delivery to brain metastatic breast cancer cells. TAT peptide-modified gold nanoparticles carrying doxorubicin led to improved cytotoxicity toward two brain metastatic breast cancer cell lines with a decrease in the IC50 of at least 80% compared to free drug. Intravenous administration of these particles led to extensive accumulation of particles throughout diffuse intracranial metastatic microsatellites with cleaved caspase-3 activity corresponding to tumor foci. Furthermore, intratumoral administration of these particles improved survival in an intracranial MDA-MB-231-Br xenograft mouse model. Our results demonstrate the promising application of gold nanoparticles for improving drug delivery in the context of brain metastatic breast cancer.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Peptídeos Penetradores de Células/química , Doxorrubicina/administração & dosagem , Ouro/química , Nanopartículas Metálicas/química , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/administração & dosagem , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Nus
12.
Proc Natl Acad Sci U S A ; 110(8): E746-55, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23386718

RESUMO

Diverse mechanisms including activation of NMDA receptors, microglial activation, reactive astrogliosis, loss of descending inhibition, and spasticity are responsible for ∼40% of cases of intractable neuropathic pain after spinal cord injury (SCI). Because conventional treatments blocking individual mechanisms elicit only short-term effectiveness, a multimodal approach with simultaneous actions against major pain-related pathways may have value for clinical management of chronic pain. We hypothesize that [-]-huperzine A (HUP-A), an alkaloid isolated from the club moss Huperzia serrata, that is a potent reversible inhibitor of acetylcholinesterase and NMDA receptors, could mitigate pain without invoking drug tolerance or dependence by stimulating cholinergic interneurons to impede pain signaling, inhibiting inflammation via microglial cholinergic activation, and blocking NMDA-mediated central hypersensitization. We tested our hypothesis by administering HUP-A i.p. or intrathecally to female Sprague-Dawley rats (200-235 g body weight) after moderate static compression (35 g for 5 min) of T10 spinal cord. Compared with controls, HUP-A treatment demonstrates significant analgesic effects in both regimens. SCI rats manifested no drug tolerance following repeated bolus i.p. or chronic intrathecal HUP-A dosing. The pain-ameliorating effect of HUP-A is cholinergic dependent. Relative to vehicle treatment, HUP-A administration also reduced neural inflammation, retained higher numbers of calcium-impermeable GluR2-containing AMPA receptors, and prevented Homer1a up-regulation in dorsal horn sensory neurons. Therefore, HUP-A may provide safe and effective management for chronic postneurotrauma pain by reestablishing homeostasis of sensory circuits.


Assuntos
Alcaloides/uso terapêutico , Dor/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Compressão da Medula Espinal/complicações , Animais , Comportamento Animal , Feminino , Dor/etiologia , Ratos , Ratos Sprague-Dawley , Compressão da Medula Espinal/fisiopatologia
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 40(7): 802-5, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26267695

RESUMO

OBJECTIVE: To observe the clinical effect on site preservation with self platelet-rich fibrin (PRF) in posterior dental areas after extraction.
 METHODS: Thirty patients who asked to extract posterior teeth and were ready for dental implantation were enrolled. PRF was implanted immediately in alveolar fossa after extraction. Cone beam computer tomography (CBCT) images were taken after 4-6 months and the changes in height and width of alveolar bone were observed.
 RESULTS: There was no statistical difference in the height and width between the alveolar bone treated with PRF after the extraction of tooth and the bone condition before the extraction of tooth.
 CONCLUSION: The site preservative technology with PRF could maintain the mass of alveolar bone in posterior dental areas, which provide a better bone condition for later dental implantation.


Assuntos
Processo Alveolar , Fibrina/uso terapêutico , Extração Dentária , Plaquetas , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária , Humanos
14.
Front Genet ; 15: 1362432, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650858

RESUMO

Background: Osteomyelitis is a severe bone marrow infection, whose pathogenesis is not yet fully understood. This study aims to explore the causal relationship between immune cell characteristics and osteomyelitis, hoping to provide new insights for the prevention and treatment of osteomyelitis. Methods: Based on two independent samples, this study employed a two-sample Mendelian randomization (MR) analysis to assess the causal relationship between 731 immune cell characteristics (divided into seven groups) and osteomyelitis. Genetic variants were used as proxies for risk factors to ensure that the selected instrumental variables meet the three key assumptions of MR analysis. Genome-Wide Association Studies (GWAS) data for immune characteristics were obtained from the public GWAS catalog, while data for osteomyelitis was sourced from the FinnGen. Results: At a significance level of 0.05, 21 immune phenotypes were identified as having a causal relationship with osteomyelitis development. In the B cell group, phenotypes such as Memory B cell % B cell (percentage of memory B cells within the total B cell population, % finger cell ratio), CD20- %B cell (percentage of B cells that do not express the CD20 marker on their surface), and Memory B cell % lymphocyte showed a positive causal relationship with osteomyelitis, while Naive-mature B cell %B cell and IgD-CD38-absolute cell counts (AC) phenotypes showed a negative causal relationship. In addition, specific immune phenotypes in the conventional dendritic cells (cDCs) group, Myeloid cell group, TBNK (T cells, B cells, natural killer cells) cell group, T cell maturation stage, and Treg cell group also showed significant associations with osteomyelitis. Through reverse MR analysis, it was found that osteomyelitis had no significant causal impact on these immune phenotypes, suggesting that the occurrence of osteomyelitis may not affect these immune cell phenotypes. Conclusion: To our knowledge, this is the first study to shed light on the causal relationship between specific immune cell characteristics and the development of osteomyelitis, thereby providing a new perspective to understand the immune mechanism of osteomyelitis. These findings are significant for formulating targeted prevention and treatment strategies, and hold promise to improve the treatment outcomes for patients with osteomyelitis.

15.
Nat Commun ; 15(1): 4792, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839760

RESUMO

Innate lymphoid cell precursors (ILCPs) develop into distinct subsets of innate lymphoid cells (ILCs) with specific functions. The epigenetic program underlying the differentiation of ILCPs into ILC subsets remains poorly understood. Here, we reveal the genome-wide distribution and dynamics of the DNA methylation and hydroxymethylation in ILC subsets and their respective precursors. Additionally, we find that the DNA hydroxymethyltransferase TET1 suppresses ILC1 but not ILC2 or ILC3 differentiation. TET1 deficiency promotes ILC1 differentiation by inhibiting TGF-ß signaling. Throughout ILCP differentiation at postnatal stage, gut microbiota contributes to the downregulation of TET1 level. Microbiota decreases the level of cholic acid in the gut, impairs TET1 expression and suppresses DNA hydroxymethylation, ultimately resulting in an expansion of ILC1s. In adult mice, TET1 suppresses the hyperactivation of ILC1s to maintain intestinal homeostasis. Our findings provide insights into the microbiota-mediated epigenetic programming of ILCs, which links microbiota-DNA methylation crosstalk to ILC differentiation.


Assuntos
Diferenciação Celular , Metilação de DNA , Proteínas de Ligação a DNA , Imunidade Inata , Linfócitos , Proteínas Proto-Oncogênicas , Animais , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Linfócitos/metabolismo , Linfócitos/imunologia , Camundongos Endogâmicos C57BL , Microbioma Gastrointestinal , Epigênese Genética , Camundongos Knockout , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais
16.
Biofactors ; 50(2): 266-293, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38059412

RESUMO

Ferroptosis is a new form of regulated cell death caused by iron-dependent accumulation of lethal polyunsaturated phospholipids peroxidation. It has received considerable attention owing to its putative involvement in a wide range of pathophysiological processes such as organ injury, cardiac ischemia/reperfusion, degenerative disease and its prevalence in plants, invertebrates, yeasts, bacteria, and archaea. To counter ferroptosis, living organisms have evolved a myriad of intrinsic efficient defense systems, such as cyst(e)ine-glutathione-glutathione peroxidase 4 system (cyst(e)ine-GPX4 system), guanosine triphosphate cyclohydrolase 1/tetrahydrobiopterin (BH4) system (GCH1/BH4 system), ferroptosis suppressor protein 1/coenzyme Q10 system (FSP1/CoQ10 system), and so forth. Among these, GPX4 serves as the only enzymatic protection system through the reduction of lipid hydroperoxides, while other defense systems ultimately rely on small compounds to scavenge lipid radicals and prevent ferroptotic cell death. In this article, we systematically summarize the chemical biology of lipid radical trapping process by endogenous chemicals, such as coenzyme Q10 (CoQ10), BH4, hydropersulfides, vitamin K, vitamin E, 7-dehydrocholesterol, with the aim of guiding the discovery of novel ferroptosis inhibitors.


Assuntos
Cistos , Ubiquinona , Humanos , Ubiquinona/metabolismo , Peroxidação de Lipídeos , Morte Celular , Peróxidos Lipídicos/metabolismo
17.
J Exp Med ; 220(10)2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37549024

RESUMO

The neuro-immune regulation is associated with homeostasis of the intestine. Intestinal group 3 innate lymphoid cells (ILC3s) are tissue-resident lymphocytes whose functions are affected by the intestine niche. However, how a gut neuronal signal coordinates the immune response of ILC3s is largely unknown. Here, we found that cyclic adenosine monophosphate (cAMP) signaling exacerbated the inflammatory response and attenuated the expression level of the transcription factor forkhead box O1 (FOXO1) in ILC3s. Deficiency of FOXO1 drove the hyperactivation of ILC3s and resulted in gut inflammation independently of T cells. Mechanistically, FOXO1 promoted the transcription of neuropeptide receptor VIPR2 and inhibited the transcription of adrenoceptor ADRA2A in ILC3s. FOXO1-related regulation of VIPR2 and ADRA2A signaling balanced the activation of ILC3s under steady condition or during colitis. Moreover, chronic stress elevated cAMP level and downregulated FOXO1 level, exacerbating intestinal inflammation. Our findings reveal that FOXO1 balances the activation of ILC3s via VIP and adrenergic signaling and regulates intestinal homeostasis.


Assuntos
Imunidade Inata , Linfócitos , Humanos , Transdução de Sinais , Inflamação/metabolismo , Homeostase , Proteína Forkhead Box O1/metabolismo
18.
Cells ; 12(24)2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38132124

RESUMO

Locomotor recovery after spinal cord injury (SCI) remains an unmet challenge. Nerve transfer (NT), the connection of a functional/expendable peripheral nerve to a paralyzed nerve root, has long been clinically applied, aiming to restore motor control. However, outcomes have been inconsistent, suggesting that NT-induced neurological reinstatement may require activation of mechanisms beyond motor axon reinnervation (our hypothesis). We previously reported that to enhance rat locomotion following T13-L1 hemisection, T12-L3 NT must be performed within timeframes optimal for sensory nerve regrowth. Here, T12-L3 NT was performed for adult female rats with subacute (7-9 days) or chronic (8 weeks) mild (SCImi: 10 g × 12.5 mm) or moderate (SCImo: 10 g × 25 mm) T13-L1 thoracolumbar contusion. For chronic injuries, T11-12 implantation of adult hMSCs (1-week before NT), post-NT intramuscular delivery of FGF2, and environmentally enriched/enlarged (EEE) housing were provided. NT, not control procedures, qualitatively improved locomotion in both SCImi groups and animals with subacute SCImo. However, delayed NT did not produce neurological scale upgrading conversion for SCImo rats. Ablation of the T12 ventral/motor or dorsal/sensory root determined that the T12-L3 sensory input played a key role in hindlimb reanimation. Pharmacological, electrophysiological, and trans-synaptic tracing assays revealed that NT strengthened integrity of the propriospinal network, serotonergic neuromodulation, and the neuromuscular junction. Besides key outcomes of thoracolumbar contusion modeling, the data provides the first evidence that mixed NT-induced locomotor efficacy may rely pivotally on sensory rerouting and pro-repair neuroplasticity to reactivate neurocircuits/central pattern generators. The finding describes a novel neurobiology mechanism underlying NT, which can be targeted for development of innovative neurotization therapies.


Assuntos
Contusões , Transferência de Nervo , Traumatismos da Medula Espinal , Ratos , Animais , Feminino , Traumatismos da Medula Espinal/terapia , Axônios , Plasticidade Neuronal
19.
Cell Mol Immunol ; 20(3): 264-276, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36600053

RESUMO

The NLRP3 inflammasome plays an essential role in resistance to bacterial infection. The nervous system secretes multiple neuropeptides affecting the nervous system as well as immune cells. The precise impact of the neuropeptide CGRP on NLRP3 inflammasome activation is still unclear. Here, we show that CGRP negatively regulates the antibacterial process of host cells. CGRP prevents NLRP3 inflammasome activation and reduces mature IL-1ß secretion. Following NLRP3 inflammasome stimulation that triggers endosome leakage, CGRP internalized to endosomal compartments is released into the cell cytosol. Cytosolic CGRP binds directly to NLRP3 and dismantles the NLRP3-NEK7 complex, which is crucial for NLRP3 inflammasome activation. CGRP administration exacerbates bacterial infection, while the treatment with a CGRP antagonist has the opposite effect. Our study uncovers a unique role of CGRP in inhibiting inflammasome activation during infections, which might shed new light on antibacterial therapies in the future.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Citosol/metabolismo , Macrófagos , Interleucina-1beta/metabolismo
20.
Cell Host Microbe ; 31(3): 418-432.e8, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36893736

RESUMO

The intestinal microbiota plays an important role in colorectal cancer (CRC) progression. However, the effect of tissue-resident commensal bacteria on CRC immune surveillance remains poorly understood. Here, we analyzed the intratissue bacteria from CRC patient colon tissues. We found that the commensal bacteria belonging to the Lachnospiraceae family, including Ruminococcus gnavus (Rg), Blautia producta (Bp), and Dorea formicigenerans (Df), were enriched in normal tissues, while Fusobacterium nucleatum (Fn) and Peptostreptococcus anaerobius (Pa) were abundant in tumor tissues. Tissue-resident Rg and Bp reduced colon tumor growth and promoted the activation of CD8+ T cells in immunocompetent mice. Mechanistically, intratissue Rg and Bp degraded lyso-glycerophospholipids that inhibited CD8+ T cell activity and maintained the immune surveillance function of CD8+ T cells. Lyso-glycerophospholipids alone promoted tumor growth that was abrogated with Rg and Bp injection. Collectively, intratissue Lachnospiraceae family bacteria facilitate the immune surveillance function of CD8+ T cells and control colorectal cancer progression.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Animais , Camundongos , Neoplasias Colorretais/microbiologia , Linfócitos T CD8-Positivos , Carcinogênese , Neoplasias do Colo/microbiologia , Fusobacterium nucleatum
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