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1.
Invest Ophthalmol Vis Sci ; 65(1): 34, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38236186

RESUMO

Purpose: The purpose of this study was to elucidate the involvement of potassium two pore domain channel subfamily K member 5 (KCNK5)-mediated potassium efflux in the pathogenesis of dry eye and to unravel the underlying molecular mechanisms. Methods: To induce experimental dry eye in adult wild-type C57BL/6 mice, scopolamine was administered via subcutaneous injection, and the mice were subjected to desiccating stress. To create an in vitro model of dry eye, desiccation stress was applied to the human corneal epithelial cell line (HCE-T). Intracellular potassium concentration was quantified using inductively coupled plasma mass spectrometry. Cellular death was assessed through lactate dehydrogenase assays. Gene expression profiling was conducted through both RNA sequencing and quantitative real-time PCR. Protein analysis was carried out through Western blotting and immunofluorescence staining. Assessment of the corneal epithelial defect area was conducted through fluorescein sodium staining. Tear secretion was quantified using the phenol red cotton thread method. Results: Potassium efflux was observed to further facilitate corneal epithelial pyroptosis. KCNK5 exhibited upregulation in both in vivo and in vitro models of dry eye. The overexpression of KCNK5 was observed to induce potassium efflux and activate the NLR family pyrin domain containing 3 (NLRP3) inflammasome-mediated pyroptosis in vitro. Silencing KCNK5 effectively mitigated pyroptosis in dry eye. Additionally, the overexpression of KCNK5 results in the downregulation of TNF superfamily member 10 (TNFSF10) and subsequent impairment of autophagy. TNFSF10 supplementation could promote autophagy and mitigate pyroptosis in dry eye. Conclusions: The upregulation of KCNK5 mediates TNFSF10 to impair autophagy and induce pyroptosis in dry eye. Consequently, targeting KCNK5 may represent a novel and promising approach to therapeutic intervention in the management of dry eye.


Assuntos
Síndromes do Olho Seco , Canais de Potássio de Domínios Poros em Tandem , Ligante Indutor de Apoptose Relacionado a TNF , Animais , Humanos , Camundongos , Autofagia , Síndromes do Olho Seco/metabolismo , Células Epiteliais , Camundongos Endogâmicos C57BL , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Piroptose , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
2.
Small Methods ; 8(3): e2300996, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37997553

RESUMO

Penetrating corneal wounds can cause severe vision impairment and require prompt intervention to restore globe integrity and minimize the risk of infection. Tissue adhesives have emerged as a promising alternative to suturing for mitigating postoperative complications. However, conventional water-soluble adhesives suffer formidable challenges in sealing penetrating corneal wounds due to dilution or loss in a moist environment. Inspired by the robust adhesion of mussels in aquatic conditions, an injectable photocurable bioadhesive hydrogel (referred to as F20HD5) composed of polyether F127 diacrylate and dopamine-modified hyaluronic acid methacrylate is developed for sutureless closure of corneal full-thickness wounds. F20HD5 exhibits high transparency, wound-sealing ability, proper viscosity, biodegradability, and excellent biocompatibility. It allows in situ cross-linking via visible light, thereby providing sufficient mechanical strength and adhesiveness. In vivo, the adhesive hydrogel effectively closed penetrating linear corneal incisions and corneal injuries with minimal tissue loss in rabbits. During the 56-day follow-up, the hydrogel facilitates the repair of the injured corneas, resulting in more symmetrical curvatures and less scarring in distinction to the untreated control. Thus, bioinspired hydrogel holds promise as an effective adhesive for sealing full-thickness corneal wounds.


Assuntos
Lesões da Córnea , Perfuração da Córnea , Animais , Coelhos , Hidrogéis/uso terapêutico , Temperatura , Córnea/cirurgia , Lesões da Córnea/cirurgia , Adesivos/farmacologia
3.
Transl Res ; 262: 25-34, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37543286

RESUMO

This study aims to investigate the efficiency and the underlying mechanism of myeloid-derived suppressor cells (MDSCs) in corneal alkali burns (CAB). In the study, CD11b+ Gr-1+ cells from C57BL/6J mice bone marrow were cultured and induced. Cell activity and immunoregulatory function were assessed by flow cytometry in vitro. The optimal strategy of MDSCs therapy was assessed by slit-lamp microscopy, and flow cytometry in vivo. The therapeutic effects of MDSCs and the critical signaling pathway were investigated by hematoxylin-eosin (HE) staining, slit-lamp microscopy, flow cytometry, and immunofluorescence. The expression level of the NLRP3 inflammasome pathway was examined. The crucial biochemical parameters of MDSCs were examined by RNA-seq and qPCR to screen out the key regulators. The mechanism of MDSCs' therapeutic effects was explored using MDSCs with IL-10 knockout/rescue by slit-lamp microscopy, HE staining, and qPCR evaluation. The cell frequencies of macrophages and neutrophils in the cornea were examined by flow cytometry in vivo. The results demonstrated that the induced MDSCs meet the standard of phenotypic and functional characteristics. The treatment of 5 × 105 MDSCs conjunctival injection on alternate days significantly ameliorated the disease development, downregulated the NLRP3 inflammasome pathway, and decreased the cell frequencies of macrophages and neutrophils in vivo significantly. IL-10 was screened out to be the critical factor for MDSCs therapy. The therapeutic effects of MDSCs were impaired largely by IL-10 knock-out and saved by the IL-10 supplement. In conclusion, MDSCs therapy is a promising therapeutic solution for CAB. MDSCs fulfilled immunoregulatory roles for CAB by IL-10-dependent anti-inflammatory properties.


Assuntos
Queimaduras Químicas , Células Supressoras Mieloides , Animais , Camundongos , Células Supressoras Mieloides/metabolismo , Interleucina-10 , Inflamassomos/metabolismo , Queimaduras Químicas/terapia , Queimaduras Químicas/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Camundongos Endogâmicos C57BL
4.
Am J Pathol ; 193(7): 883-898, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37146965

RESUMO

Fungal keratitis remains a major cause of severe visual loss in developing countries because of limited choices of therapy. The progression of fungal keratitis is a race between the innate immune system and the outgrowth of fungal conidia. Programmed necrosis (necroptosis), a type of proinflammatory cell death, has been recognized as a critical pathologic change in several diseases. However, the role and potential regulatory mechanisms of necroptosis have not been investigated in corneal diseases. The current study showed, for the first time, that fungal infection triggered significant corneal epithelial necroptosis in human/mouse/in vitro models. Moreover, a reduction in excessive reactive oxygen species release effectively prevented necroptosis. NLRP3 knockout did not affect necroptosis in vivo. In contrast, ablation of necroptosis via RIPK3 knockout significantly delayed migration and inhibited the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in macrophages, which enhanced the progression of fungal keratitis. Taking these findings together, the study indicated that overproduction of reactive oxygen species in fungal keratitis leads to significant necroptosis in the corneal epithelium. Furthermore, the necroptotic stimuli-mediated NLRP3 inflammasome serves as a driving force in host defense against fungal infection.


Assuntos
Inflamassomos , Ceratite , Humanos , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Necroptose , Apoptose/fisiologia , Proteínas Quinases/metabolismo , Estresse Oxidativo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
5.
Invest Ophthalmol Vis Sci ; 64(3): 34, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36988949

RESUMO

Purpose: To investigate the effect of gamma interferon (IFN-γ) on corneal epithelial pyroptosis in an experimental dry eye (DE) model and explore the underlying molecular mechanisms. Methods: Experimental DE was established in adult wild-type (WT) C57BL/6 mice and Ifng-knockout mice on a C57BL/6 background by subcutaneous injection of scopolamine (1.5 mg/0.3 mL, three times per day) and exposure to desiccating stress. An immortalized human corneal epithelial cell line (HCE-T) was treated with IFN-γ under hyperosmolar conditions. Corneal epithelial defects, tear production, and conjunctival goblet cells were detected by fluorescein sodium staining, the phenol red cotton test, and periodic acid-Schiff staining. The mRNA expression was measured by quantitative real-time PCR. Changes in protein expression were analyzed by Western blotting and immunofluorescence staining. Cell Counting Kit-8 and lactate dehydrogenase assays and in situ TUNEL staining were used to assess cell death. Results: The expression of IFNG and its related genes was increased in the corneas of DE mice, whereas genetic deletion of Ifng ameliorated desiccating stress-induced dry eye symptoms. We further found that IFN-γ activated the JAK2/STAT1 signaling pathway inducing corneal epithelial pyroptosis. Topical application of a STAT1 inhibitor in vivo or siRNA targeting STAT1 in vitro suppressed pyroptosis of corneal epithelial cells. In addition, the production of reactive oxygen species (ROS) was elevated in DE, and a reduction in excessive ROS release prevented pyroptosis. Conclusions: The increase in IFN-γ participates in the pathogenesis of dry eye and promotes corneal epithelial pyroptosis by activating the JAK2/STAT1 signaling pathway. Oxidative stress might be in downstream of JAK2/STAT1, thereby contributing to pyroptosis.


Assuntos
Síndromes do Olho Seco , Interferon gama , Humanos , Animais , Camundongos , Interferon gama/metabolismo , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Síndromes do Olho Seco/metabolismo , Camundongos Endogâmicos C57BL , Células Epiteliais/metabolismo , Fator de Transcrição STAT1/metabolismo , Janus Quinase 2/efeitos adversos , Janus Quinase 2/metabolismo
6.
ACS Biomater Sci Eng ; 8(11): 4850-4862, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36214483

RESUMO

Conventional administration of eye drops often requires high dosages and/or repetitive treatments to achieve therapeutic efficacy. This is inefficient and may result in side effects or even toxicity. Although many delivery systems of ophthalmic drugs have been reported, most of them work in a fixed format in which both the type and dose of the loaded drugs cannot be changed upon demand. To overcome this limitation, a hybrid double network hydrogel system composed of methacryloyl gelatin, pluronic F127 diacrylate, and ß-cyclodextrin-modified oxidized dextran was developed. The hydrogels presented good mechanical strength and biocompatibility. In vitro assessments demonstrated that the hydrogels loaded with commonly used ophthalmic drugs could sustain the drug release for more than 21 days. This hydrogel system exhibited features of mechanoresponsive drug loading, and the capacity of drug loading could be significantly enhanced by macroscopically mechanical compression. Further in vivo evaluation of the drug delivery capacity showed that a dexamethasone-loaded hydrogel as a fornix insert effectively suppressed upregulation of proangiogenic factors and suture-induced corneal neovascularization in rats. This novel hydrogel system represents a promising drug delivery platform, which could potentially improve the treatments of ocular surface and other diseases.


Assuntos
Sistemas de Liberação de Medicamentos , Oftalmopatias , Ratos , Animais , Hidrogéis/farmacologia , Gelatina , Liberação Controlada de Fármacos , Oftalmopatias/tratamento farmacológico
7.
Invest Ophthalmol Vis Sci ; 63(10): 3, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066316

RESUMO

Purpose: To evaluate the precise mode of cell death and to investigate the molecular mechanism underlying the initiation of inflammation in dry eye disease (DED). Methods: C57BL/6 mice were injected with scopolamine subcutaneously and exposed to desiccating stress to establish a DED mouse model. An immortalized human corneal epithelial cell line (HCEC) was cultured under hyperosmolarity (500 mOsM). Protein expressions were measured using western blot assay and immunofluorescence staining. mRNA expression was analyzed by RNA-sequencing and quantitative RT-PCR. Transmission electron microscopy was used to observe the intracellular ultrastructure. Intracellular Fe2+ was detected by a FerroOrange fluorescent probe. Flow cytometry was used to evaluate the cellular reactive oxygen species and lipid peroxidation. Results: Marked changes in ferroptosis-related markers expression, intracellular iron accumulation, and lipid peroxidation were observed in corneal epithelial cells of DED models. When excessive oxidative stress was suppressed, ferroptosis induced by hyperosmolarity in HCECs was restrained, as indicated by decreased iron content and lipid peroxidation levels. Moreover, AKR1C1 was upregulated by the activation of NRF2 in HCECs under hyperosmolarity. When AKR1C1 was knocked down, cell viability was decreased, accompanied by increased lipid peroxidation, whereas overexpression of AKR1C1 produced the opposite results. It was observed consistently that corneal defects and the inflammatory response were promoted after inhibition of AKR1C1 in vivo. Conclusions: Excessive oxidative stress-induced ferroptosis participates in DED pathogenesis. The expression of AKR1C1 is triggered by NRF2 to decrease ferroptosis-induced cell damage and inflammation in HCECs. These findings may provide potential makers targeting ferroptosis and AKR1C1 for DED therapy.


Assuntos
Síndromes do Olho Seco , Ferroptose , Animais , Síndromes do Olho Seco/metabolismo , Células Epiteliais/metabolismo , Humanos , Inflamação/metabolismo , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo
8.
Bioeng Transl Med ; 7(3): e10304, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36176602

RESUMO

Fungal pathogens are common causes of superficial clinical infection. Their increasing drug resistance gradually makes existing antifungal drugs ineffective. Heat stable antifungal factor (HSAF) is a novel antifungal natural product with a unique structure. However, the application of HSAF has been hampered by very low yield in the current microbial producers and from extremely poor solubility in water and common solvents. In this study, we developed an effective mode of treatment applying HSAF to superficial fungal infections. The marine-derived Lysobacter enzymogenes YC36 contains the HSAF biosynthetic gene cluster, which we activated by the interspecific signaling molecule indole. An efficient extraction strategy was used to significantly improve the purity to 95.3%. Scanning electron microscopy images revealed that the Type I collagen-based HSAF (Col-HSAF) has a transparent appearance and good physical properties, and the in vitro sustained-release effect of HSAF was maintained for more than 2 weeks. The effective therapeutic concentration of Col-HSAF against superficial fungal infection was explored, and Col-HSAF showed good biocompatibility, lower clinical scores, mild histological changes, and antifungal capabilities in animals with Aspergillus fumigatus keratitis and cutaneous candidiasis. In conclusion, Col-HSAF is an antifungal reagent with significant clinical value in the treatment of superficial fungal infections.

9.
Dis Markers ; 2022: 1380560, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845133

RESUMO

Fungal keratitis, one of the most common infectious eye diseases in China, often results in a poor prognosis due to a delayed diagnosis and the insufficiency of effective therapy. There is an urgent need to identify specific biomarkers for the disease. In this study, we screened out tear proteins in patients with fungal keratitis by microsphere-based immunoassay analysis. Levels of cytokine expression were determined in both human corneal epithelial cell models in vitro and the corneas of patients by western blot, quantitative polymerase chain reaction (qPCR), and immunofluorescence analysis. Neutrophil activation was examined by flow cytometry analysis. The relationship between the cytokine expression and neutrophils was evaluated by immunofluorescence costaining and correlation analysis. These results demonstrated that the galectin-3 expression level was increased in both cell model and patient samples at the early and late stages of fungal keratitis. The neutrophils were significantly activated during the disease course of fungal keratitis. Meanwhile, colocalization and a positive correlation between galectin-3 and neutrophils were observed, suggesting that galectin-3 may play a crucial role in the recruitment of neutrophils and immune regulation of fungal keratitis. In conclusion, galectin-3 could be a key disease marker implying a beneficial immune response in the pathogenesis of fungal keratitis, which might be a target of therapeutic strategy in the future.


Assuntos
Aspergilose , Infecções Oculares Fúngicas , Doenças do Sistema Imunitário , Ceratite , Animais , Aspergilose/tratamento farmacológico , Aspergilose/metabolismo , Biomarcadores , Citocinas/uso terapêutico , Modelos Animais de Doenças , Infecções Oculares Fúngicas/metabolismo , Galectina 3/genética , Humanos , Ceratite/tratamento farmacológico , Ceratite/microbiologia , Ceratite/patologia , Camundongos , Camundongos Endogâmicos C57BL
10.
Dis Markers ; 2022: 8316004, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437453

RESUMO

Galectin-3 is one of the galectin family members which are master regulators of immune homeostasis, especially in infectious diseases. However, its mechanism of immune regulation in fungal keratitis has not been thoroughly studied. Our study is aimed at clarifying the role of galectin-3 in the fungal keratitis mouse model in vivo, thereby providing a new biomarker of antifungal therapy. In our study, aspergillus, the most common pathogenic fungi of fungal keratitis, was identified and isolated by corneal tissue fungus culture. Then, the RNA expression levels of galectin family members in corneas of the mouse model with aspergillus fumigatus keratitis were screened by transcriptome sequencing (RNA-seq). The expression of the galectin-3 was detected by quantitative real-time Polymerase Chain Reaction (qPCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence in the corneal tissue of the fungal keratitis mouse model. Recruitment of neutrophils and the co-immunofluorescence of galectin-3 and related markers in corneal tissue were determined by flow cytometry analysis and immunofluorescence staining. The regulatory role of galectin-3 for proinflammatory cytokines and neutrophils was validated by the knockout mouse model. Galectin-3 knockout deteriorated the condition for the inhibition of galectin-3 was benefecial for fungi to survive and thrive in corneal lesions. These results demonstrated that in the ocular fungal infection, galectin-3 is capable of regulating the pathogenesis of fungal keratitis by modulating neutrophil recruitment. The deterioration of fungal keratitis and increased fungal load in corneal lesions of galectin-3 knockout mice proved the regulatory role of galectin-3 in fungal keratitis. In conclusion, galectin-3 is going to be an essential target to modulate neutrophil recruitment and its related antifungal immune response in fungal keratitis.


Assuntos
Aspergilose , Infecções Oculares Fúngicas , Ceratite , Animais , Antifúngicos/uso terapêutico , Aspergilose/metabolismo , Aspergilose/microbiologia , Modelos Animais de Doenças , Infecções Oculares Fúngicas/metabolismo , Infecções Oculares Fúngicas/microbiologia , Galectina 3/genética , Humanos , Imunidade , Ceratite/metabolismo , Ceratite/microbiologia , Camundongos , Camundongos Endogâmicos C57BL
11.
Bioact Mater ; 8: 196-209, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34541396

RESUMO

Keratoplasty is the gold standard treatment for visual impairment caused by corneal damage. The use of suturing as the bonding method is the source of many complications following keratoplasty. Currently available corneal adhesives do not have both adequate adhesive strength and acceptable biocompatibility. Herein, we developed a photocurable bioadhesive hydrogel which was composed of gelatin methacryloyl and oxidized dextran for sutureless keratoplasty. The bioadhesive hydrogel exhibited high light transmittance, resistance to enzymatic degradation and excellent biocompatibility. It also had higher adhesive strength than commercial adhesives (fibrin glue). In a rabbit model of lamellar keratoplasty, donor corneal grafts could be closely bonded to the recipient corneal bed and remained attached for 56 days by using of this in situ photopolymerized bioadhesive hydrogel. The operated cornea maintained transparent and noninflamed. Sutureless keratoplasty using bioadhesive hydrogel allowed rapid graft re-epithelialization, typically within 7 days. In vivo confocal microscopic and histological evaluation of the operated cornea did not show any apparent abnormalities in terms of corneal cells and ultrastructure. Thus, this bioadhesive hydrogel is exhibited to be an appealing alternative to sutures for keratoplasty and other corneal surgeries.

12.
Front Med (Lausanne) ; 8: 781616, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096875

RESUMO

Dry eye disease (DED) is one of the most common ocular surface diseases worldwide. DED has been characterized by excessive accumulation of reactive oxygen species (ROS), following significant corneal epithelial cell death and ocular surface inflammation. However, the key regulatory factor remains unclear. In this study, we tended to explore whether DUOX2 contributed to DED development and the underlying mechanism. Human corneal epithelial (HCE) cells were treated with hyperosmolarity, C57BL/6 mice were injected of subcutaneous scopolamine to imitate DED. Expression of mRNA was investigated by RNA sequencing (RNA-seq) and quantitative real-time PCR (qPCR). Protein changes and distribution of DUOX2, high mobility group box 1 (HMGB1), Toll-like receptor 4 (TLR4), and 4-hydroxynonenal (4-HNE) were evaluated by western blot assays and immunofluorescence. Cell death was assessed by Cell Counting Kit-8 (CCK8), lactate dehydrogenase (LDH) release, and propidium iodide (PI) staining. Cellular ROS levels and mitochondrial membrane potential (MMP) were analyzed by flow cytometry. RNA-seq and western blot assay indicated a significant increase of DUOX2 dependent of TLR4 activation in DED both in vitro and in vivo. Immunofluorescence revealed significant translocation of HMGB1 within corneal epithelial cells under hyperosmolar stress. Interestingly, after ablated DUOX2 expression by siRNA, we found a remarkable decrease of ROS level and recovered MMP in HCE cells. Moreover, knockdown of DUOX2 greatly inhibited HMGB1 release, protected cell viability and abolished inflammatory activation. Taken together, our data here suggest that upregulation of DUOX2 plays a crucial role in ROS production, thereafter, induce HMGB1 release and cell death, which triggers ocular surface inflammation in DED.

13.
Int Immunopharmacol ; 85: 106649, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32504999

RESUMO

Immune modulation plays a critical role in the pathogenesis of fungal keratitis (FK). However, the immune cell-mediated processes linking the innate immune response to the adaptive immune response are incompletely elucidated. IL-6 plays crucial roles in infectious and inflammatory processes in the cornea, regulating not only mononuclear macrophage differentiation but also lymphocyte activation, and IL-6 might be a useful target for immune intervention in FK. The frequencies of macrophages and T cells increased upon infection and were correlated with the severity of ocular pathogenesis. Additionally, protein profiling revealed that the expression of IL-6 and associated cytokines/chemokines was upregulated. Furthermore, anti-IL-6 intervention suppressed disease progression by reducing macrophage infiltration in the cornea and Th1, Th17, and Treg cell infiltration in draining lymph nodes (DLN) in an animal model of FK. Tocilizumab (TCZ), an antibody specific for IL-6, reduced the signal transducer and activator of transcription 3 (STAT3) activation in vivo and in vitro. In summary, fungal infection promoted macrophage and T cell activation via IL-6-mediated transcellular signaling to regulate immune cell migration and cytokine production, further demonstrating the role of IL-6 and providing a potential clinical therapeutic target in FK.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Infecções Oculares Fúngicas/tratamento farmacológico , Interleucina-6/antagonistas & inibidores , Ceratite/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Aspergilose/imunologia , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Infecções Oculares Fúngicas/imunologia , Feminino , Interleucina-6/imunologia , Ceratite/imunologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
14.
Front Immunol ; 10: 2151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572371

RESUMO

Current combined antiretroviral therapy (cART) mainly targets 3 of the 15 HIV proteins leaving many potential viral vulnerabilities unexploited. To purge the HIV-1 latent reservoir, various strategies including "shock and kill" have been developed. A key question is how to restore impaired immune surveillance. HIV-1 protein Nef has long been known to mediate the downregulation of cell-surface MHC-I and assist HIV-1 to evade the immune system. Through high throughput screening of Food and Drug Administration (FDA) approved drugs, we identified lovastatin, a statin drug, to significantly antagonize Nef to downregulate MHC-I, CD4, and SERINC5, and inhibit the intrinsic infectivity of virions. In addition, lovastatin boosted autologous CTLs to eradicate the infected cells and effectively inhibit the subsequent viral rebound in CD4+ T-lymphocytes isolated from HIV-1-infected individuals receiving suppressive cART. Furthermore, we found that lovastatin inhibits Nef-induced MHC-I downregulation by directly binding with Nef and disrupting the Nef-AP-1 complex. These results demonstrate that lovastatin is a promising agent for counteracting Nef-mediated downregulation of MHC-I, CD4, and SERINC5. Lovastatin could potentially be used in the clinic to enhance anti-HIV-1 immune surveillance.


Assuntos
Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Lovastatina/farmacologia , Antígenos CD4/imunologia , Células Cultivadas , Técnicas de Cocultura , Regulação para Baixo , HIV-1 , Humanos , Proteínas de Membrana/imunologia , Linfócitos T/imunologia , Fator de Transcrição AP-1/imunologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/imunologia
15.
Invest Ophthalmol Vis Sci ; 60(8): 2836-2847, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31266058

RESUMO

Purpose: To assess how DNA damage-inducible transcript 4 (DDIT4) and autophagic flux are altered in dry eye disease and reveal the underlying mechanisms. Methods: C57BL/6 mice were exposed to desiccating stress (subcutaneous scopolamine [0.5 mg/0.2 mL] 3 times a day, humidity < 30%) for 7 days. Primary human corneal epithelial cells and cells from a human corneal epithelial cell line were cultured under hyperosmolarity. Western blot assays and immunofluorescence staining were used to measure changes in protein expression. mRNA expression was analyzed by RT-PCR and quantitative real-time PCR. Autophagosomes were observed through electron microscopy. Cellular reactive oxygen species and mitochondrial function were detected with 2',7'-dichlorodihydrofluorescein diacetate and mitochondrial membrane potential assays. Cell Counting Kit-8 and lactate dehydrogenase assays were used to measure cell death. Apoptosis was analyzed by Annexin V-PI flow cytometry. Results: Increased expression of microtubule-associated protein 1 light chain 3 (LC3-II), sequestosome 1 (SQSTM1), and DDIT4 were observed in corneal epithelial cells in in vitro and mice models of dry eye. The electron microscopy revealed large autophagic vacuoles with poorly degraded materials in human corneal epithelial cells under hyperosmolarity. In addition, we found that DDIT4 knockdown significantly suppressed the expression of LC3-II and SQSTM1 by disrupting reactive oxygen species release and restoring mitochondrial function under hyperosmolarity. Moreover, the ablation of DDIT4 effectively preserved cell viability and inhibited apoptosis. Conclusions: Excessive reactive oxygen species release through DDIT4 induction can lead to impaired autophagy and decreased cell viability in dry eye disease.


Assuntos
Autofagia , Síndromes do Olho Seco/metabolismo , Estresse Oxidativo/fisiologia , Fatores de Transcrição/metabolismo , Animais , Anexina A5/metabolismo , Apoptose/fisiologia , Autofagia/fisiologia , Western Blotting , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Epitélio Corneano/metabolismo , Epitélio Corneano/patologia , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1/metabolismo
16.
J Virol ; 90(21): 9712-9724, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27535056

RESUMO

Despite the advent of combined antiretroviral therapy (cART), the persistence of viral reservoirs remains a major barrier to curing human immunodeficiency virus type 1 (HIV-1) infection. Recently, the shock and kill strategy, by which such reservoirs are eradicated following reactivation of latent HIV-1 by latency-reversing agents (LRAs), has been extensively practiced. It is important to reestablish virus-specific and reliable immune surveillance to eradicate the reactivated virus-harboring cells. In this report, we attempted to reach this goal by using newly developed chimeric antigen receptor (CAR)-T cell technology. To generate anti-HIV-1 CAR-T cells, we connected the single-chain variable fragment of the broadly neutralizing HIV-1-specific antibody VRC01 to a third-generation CAR moiety as the extracellular and intracellular domains and subsequently transduced this into primary CD8+ T lymphocytes. We demonstrated that the resulting VC-CAR-T cells induced T cell-mediated cytolysis of cells expressing HIV-1 Env proteins and significantly inhibited HIV-1 rebound after removal of antiviral inhibitors in a viral infectivity model in cell culture that mimics the termination of the cART in the clinic. Importantly, the VC-CAR-T cells also effectively induced the cytolysis of LRA-reactivated HIV-1-infected CD4+ T lymphocytes isolated from infected individuals receiving suppressive cART. Our data demonstrate that the special features of genetically engineered CAR-T cells make them a particularly suitable candidate for therapeutic application in efforts to reach a functional HIV cure. IMPORTANCE: The presence of latently infected cells remains a key obstacle to the development of a functional HIV-1 cure. Reactivation of dormant viruses is possible with latency-reversing agents, but the effectiveness of these compounds and the subsequent immune response require optimization if the eradication of HIV-1-infected cells is to be achieved. Here, we describe the use of a chimeric antigen receptor, comprised of T cell activation domains and a broadly neutralizing antibody, VRC01, targeting HIV-1 to treat the infected cells. T cells expressing this construct exerted specific cytotoxic activity against wild-type HIV-1-infected cells, resulting in a dramatic reduction in viral rebound in vitro, and showed persistent effectiveness against reactivated latently infected T lymphocytes from HIV-1 patients receiving combined antiretroviral therapy. The methods used in this study constitute an improvement over existing CD4-based CAR-T technology and offer a promising approach to HIV-1 immunotherapy.


Assuntos
Anticorpos Neutralizantes/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Anticorpos de Cadeia Única/imunologia , Fármacos Anti-HIV/farmacologia , Anticorpos Bloqueadores/efeitos dos fármacos , Anticorpos Bloqueadores/imunologia , Linhagem Celular , Células HEK293 , Anticorpos Anti-HIV/imunologia , Humanos , Receptores de Antígenos de Linfócitos T/imunologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/imunologia , Latência Viral/efeitos dos fármacos , Latência Viral/imunologia
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