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1.
Cell Oncol (Dordr) ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809326

RESUMO

PURPOSE: Leukaemia remains a major contributor to global mortality, representing a significant health risk for a substantial number of cancer patients. Despite notable advancements in the field, existing treatments frequently exhibit limited efficacy or recurrence. Here, we explored the potential of abolishing HVEM (herpes virus entry mediator, TNFRSF14) expression in tumours as an effective approach to treat acute lymphoblastic leukaemia (ALL) and prevent its recurrence. METHODS: The clinical correlations between HVEM and leukaemia were revealed by public data analysis. HVEM knockout (KO) murine T cell lymphoblastic leukaemia cell line EL4 were generated using CRISPR-Cas9 technology, and syngeneic subcutaneous tumour models were established to investigate the in vivo function of HVEM. Immunohistochemistry (IHC), RNA-seq and flow cytometry were used to analyse the tumour immune microenvironment (TIME) and tumour draining lymph nodes (dLNs). Immune functions were investigated by depletion of immune subsets in vivo and T cell functional assays in vitro. The HVEM mutant EL4 cell lines were constructed to investigate the functional domain responsible for immune escape. RESULTS: According to public databases, HVEM is highly expressed in patients with ALL and acute myeloid leukemia (AML) and is negatively correlated with patient prognosis. Genetic deletion of HVEM in EL4 cells markedly inhibited tumour progression and prolonged the survival of tumour-bearing mice. Our experiments proved that HVEM exerted its immunosuppressive effect by inhibiting antitumour function of CD8+ T cell through CRD1 domain both in vivo and in vitro. Additionally, we identified a combination therapy capable of completely eradicating ALL tumours, which induces immune memory toward tumour protection. CONCLUSIONS: Our study reveals the potential mechanisms by which HVEM facilitates ALL progression, and highlights HVEM as a promising target for clinical applications in relapsed ALL therapy.

2.
Nat Cancer ; 5(3): 500-516, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38200243

RESUMO

Immunosuppressive myeloid cells hinder immunotherapeutic efficacy in tumors, but the precise mechanisms remain undefined. Here, by performing single-cell RNA sequencing in colorectal cancer tissues, we found tumor-associated macrophages and granulocytic myeloid-derived suppressor cells increased most compared to their counterparts in normal tissue and displayed the highest immune-inhibitory signatures among all immunocytes. These cells exhibited significantly increased expression of immunoreceptor tyrosine-based inhibitory motif-bearing receptors, including SIRPA. Notably, Sirpa-/- mice were more resistant to tumor progression than wild-type mice. Moreover, Sirpα deficiency reprogramed the tumor microenvironment through expansion of TAM_Ccl8hi and gMDSC_H2-Q10hi subsets showing strong antitumor activity. Sirpa-/- macrophages presented strong phagocytosis and antigen presentation to enhance T cell activation and proliferation. Furthermore, Sirpa-/- macrophages facilitated T cell recruitment via Syk/Btk-dependent Ccl8 secretion. Therefore, Sirpα deficiency enhances innate and adaptive immune activation independent of expression of CD47 and Sirpα blockade could be a promising strategy to improve cancer immunotherapy efficacy.


Assuntos
Antígeno CD47 , Neoplasias Colorretais , Camundongos , Animais , Antígeno CD47/genética , Antígeno CD47/metabolismo , Fagocitose , Macrófagos/metabolismo , Células Mieloides/metabolismo , Neoplasias Colorretais/patologia , Microambiente Tumoral
3.
Eur J Immunol ; 53(11): e2350375, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37672390

RESUMO

Signal regulatory protein alpha (SIRPα) is a crucial inhibitory regulator expressed on the surface of myeloid cells, including macrophages, dendritic cells, monocytes, neutrophils, and microglia. SIRPα plays an indispensable role in innate immune and adoptive immune responses in cancer immunology, tissue homeostasis, and other physiological or phycological conditions. This review provides an overview of the research history, ligands, signal transduction pathways, and functional mechanisms associated with SIRPα. Additionally, we summarize the therapeutic implications of targeting SIRPα as a promising novel strategy in immuno-oncology.


Assuntos
Neoplasias , Fagocitose , Humanos , Imunidade Inata , Macrófagos , Células Mieloides/metabolismo , Antígenos de Diferenciação
4.
Nat Cancer ; 4(9): 1273-1291, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37460871

RESUMO

Neoadjuvant immune-checkpoint blockade therapy only benefits a limited fraction of patients with glioblastoma multiforme (GBM). Thus, targeting other immunomodulators on myeloid cells is an attractive therapeutic option. Here, we performed single-cell RNA sequencing and spatial transcriptomics of patients with GBM treated with neoadjuvant anti-PD-1 therapy. We identified unique monocyte-derived tumor-associated macrophage subpopulations with functional plasticity that highly expressed the immunosuppressive SIGLEC9 gene and preferentially accumulated in the nonresponders to anti-PD-1 treatment. Deletion of Siglece (murine homolog) resulted in dramatically restrained tumor development and prolonged survival in mouse models. Mechanistically, targeting Siglece directly activated both CD4+ T cells and CD8+ T cells through antigen presentation, secreted chemokines and co-stimulatory factor interactions. Furthermore, Siglece deletion synergized with anti-PD-1/PD-L1 treatment to improve antitumor efficacy. Our data demonstrated that Siglec-9 is an immune-checkpoint molecule on macrophages that can be targeted to enhance anti-PD-1/PD-L1 therapeutic efficacy for GBM treatment.


Assuntos
Glioblastoma , Humanos , Animais , Camundongos , Glioblastoma/genética , Glioblastoma/terapia , Antígeno B7-H1 , Proteínas de Checkpoint Imunológico/genética , Proteínas de Checkpoint Imunológico/uso terapêutico , Linfócitos T CD8-Positivos/patologia , Imunoterapia/métodos , Macrófagos/patologia
5.
Acta Pharmacol Sin ; 44(6): 1217-1226, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36650291

RESUMO

Retinoic-acid-receptor-related orphan receptor γ (RORγ) is a major transcription factor for proinflammatory IL-17A production. Here, we revealed that the RORγ deficiency protects mice from STZ-induced Type 1 diabetes (T1D) through inhibiting IL-17A production, leading to improved pancreatic islet ß cell function, thereby uncovering a potential novel therapeutic target for treating T1D. We further identified a novel RORγ inverse agonist, ginseng-derived panaxadiol, which selectively inhibits RORγ transcriptional activity with a distinct cofactor recruitment profile from known RORγ ligands. Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for panaxadiol in the RORγ ligand-binding pocket. Despite its inverse agonist activity, panaxadiol induced the C-terminal AF-2 helix of RORγ to adopt a canonical active conformation. Interestingly, panaxadiol ameliorates mice from STZ-induced T1D through inhibiting IL-17A production in a RORγ-dependent manner. This study demonstrates a novel regulatory function of RORγ with linkage of the IL-17A pathway in pancreatic ß cells, and provides a valuable molecule for further investigating RORγ functions in treating T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Panax , Animais , Camundongos , Interleucina-17/metabolismo , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/tratamento farmacológico , Ligantes , Agonismo Inverso de Drogas , Panax/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas
6.
Clin Cosmet Investig Dermatol ; 14: 1355-1365, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594126

RESUMO

PURPOSE: Psoriasis is a common cutaneous disease with multiple characteristics including inflammation and aberrant keratinocyte proliferation. However, the pathogenesis of psoriasis is not completely clear yet. The objective of this study is to perform an in-depth analysis of the association between SPRR and LCE in the pathogenesis of psoriasis. METHODS: In this study, we explore the differentially expressed genes (DEGs) in psoriasis by analyzing different gene expression profiles obtained from the Gene Expression Omnibus (GEO) database. The DEGs were examined using gene ontology (GO) functional enrichment analysis and protein-protein interactions (PPI) network. Correlation analysis in R studio software was used to analyze the association between SPRR and LCE genes. Further, potential direct protein-protein interactions between SPRR proteins and LCE3D were verified by co-localization observations and co-immunoprecipitation (CO-IP) assays in 293T cells. Also, the expression levels of SPRR and LCE genes were detected in lesional skin of the IMQ-induced psoriasiform dermatitis mice using RT-PCR. RESULTS: Interestingly, the small proline-rich (SPRR) and late cornified envelope (LCE) genes were identified as a module in the constructed PPI network. And the analysis of the gene expression profile GSE63684 showed that both SPRR family and LCE family genes were significantly upregulated in imiquimod (IMQ) induced psoriasiform dermatitis mice. Also, the correlation analysis in R studio software recognized the association of SPRR and LCE genes, which were further verified by co-localization and co-immunoprecipitation (CO-IP) assays in 293T cells, and the results show that the direct interactions between SPRR2 and LCE3D. Notably, we also found that the expression levels of SPRR and LCE genes were significantly increased in the IMQ-induced psoriasiform dermatitis mice, while specifically decreased under the tazarotene cream treatment, indicating that the SPRR and LCEs were regulated simultaneously in psoriasis. CONCLUSION: In summary, our study found that interactions between SPRR proteins and LCE proteins may provide new insights into the pathogenesis of psoriasis.

7.
Langmuir ; 37(39): 11592-11602, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34558895

RESUMO

Silanization processes with perfluoroalkyl silanes have been demonstrated to be effective in developing advanced materials with many functional properties, including hydrophobicity, water repellency, and self-cleaning properties. However, practical industrial applications of perfluoroalkyl silanes are limited by their extremely high cost. On the basis of our recent work on photoredox catalysis for amidation with perfluoroalkyl iodides, its application for surface chemical modification on filter paper, as an illustrative example, has been developed and evaluated. Before photocatalytic amidation, the surface is functionalized with amine functional groups by silanization with 3-(trimethoxysilyl)propylamine. All chemically modified surfaces have been fully characterized by attenuated total reflection infrared (ATR-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), and three-dimensional (3D) profiling to confirm the successful silanization and photocatalytic amidation. After surface modification of the filter papers with perfluoroalkanamide, they show high water repellency and hydrophobicity with contact angles over 120°. These filter papers possess high wetting selectivity, which can be used to effectively separate the organic and aqueous biphasic mixtures. The perfluoroalkanamide-modified filter papers can be used for separating organic/aqueous biphasic mixtures over many cycles without lowering the separating efficiency, indicating their reusability and excellent durability.

8.
Bioresour Technol ; 340: 125621, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34325396

RESUMO

Pseudomonas chloritidismutans K14, a novel phosphate-accumulating organism with the capacity to perform ammonium assimilation, aerobic denitrification, and phosphorus removal, was isolated from aquaculture sediments. It produced no hemolysin, and showed susceptibility to most antibiotics. Optimum conditions were achieved with sodium pyruvate as a carbon source, a C/N ratio of 10, pH of 7.5, temperature of 27 °C, P/N ratio of 0.26, and shaking at 140 rpm. Under optimum conditions, the highest removal efficiencies of ammonium, nitrite, and nitrate were 99.82%, 99.11%, and 99.78%, respectively; the corresponding removal rates were 6.27, 4.51, and 4.99 mg/L/h. The strain removed over 98% of phosphorus, and over 87% of chemical oxygen demand. The highest biomass nitrogen during ammonium assimilation was 99.18 mg/L; no gaseous nitrogen was produced. The genes involved in nitrogen and phosphorus removal were amplified by PCR. This study demonstrated the potential application prospects of strain K14 for nitrogen and phosphorus removal.


Assuntos
Compostos de Amônio , Nitrogênio , Aerobiose , Desnitrificação , Nitrificação , Fosfatos , Fósforo , Pseudomonas
9.
Dalton Trans ; 47(12): 4368-4376, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29497725

RESUMO

Cation disorder in the phosphor lattice could be one of the effective approaches to modify the luminescence efficiency. In this work, cation substitutions of (Mo6+→ V5+) and (Na+→ Mg2+) were conducted in the self-activated NaMg2V3O10. All the samples of Na1+xMg2-xV3-xMoxO10 (x = 0, 0.01, 0.05, 0.1, 0.2, 0.3) were prepared via solid-state reaction. The morphological properties were measured via SEM and EDS analyses. Structural Rietveld refinement was performed to investigate the microstructure in the lattices. The cation substitution brings about structural disorder in the phosphor, which exerts great modifications in the luminescence properties. NaMg2V3O10 presents an intrinsic indirect transition with a band gap of 3.22 eV. The incorporation of Mo6+ and Na+ in the lattices moves the optical absorption to a longer wavelength bringing about a narrower band gap. The luminescence intensity, thermal stability and corresponding lifetime were modified by the cation disorder in the self-activated phosphor.

10.
Artigo em Inglês | MEDLINE | ID: mdl-29128751

RESUMO

Silver-containing lanthanum metaniobate Ag0.5La0.5Nb2O6 nanoparticles were synthesized by sol-gel polymerized complex method. A typical defect-perovskite structure was confirmed by XRD Rietveld refinements. The surface characteristics of the sample were tested by SEM, TEM and EDS measurements. SEM and TEM show that the sample presents ball-like particles with the diameters of 100nm to 400nm. The sample shows both self-activated luminescence and photocatalytic activities. Ag0.5La0.5Nb2O6 has a direct transition with band energy of 2.85eV. The Ag4d-O2p hybridization in the valence band contributes to the narrowed band gap. The luminescence properties of Ag0.5La0.5Nb2O6 have been investigated for the first time. The luminescence is characterized by two emission centers with maximum wavelength near 460 and 530nm. The emission and excitation spectra, decay curves and the thermal quenching mechanism were discussed. Ag0.5La0.5Nb2O6 shows the efficient photocatalytic activities and the photodegradation rate for methylene blue dye (MB) can reach about 95% under visible light (>420nm) irradiation in 5h. The trapped experiments for the active species were tested and discussed, which verified that OH radicals could be the major active species in photocatalysis.

11.
J Hepatobiliary Pancreat Sci ; 19(6): 674-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22187145

RESUMO

PURPOSE: To evaluate the efficacy and safety of ultrasound (US)-guided percutaneous argon-helium cryoablation for hepatocellular carcinoma (HCC) and determine appropriate indications. METHODS: We reviewed outcomes of 300 HCC patients who underwent US-guided percutaneous cryoablation. RESULTS: Overall, 223 tumors (mean diameter 7.2 ± 2.8 cm) in 165 patients were incompletely ablated, while 185 tumors (mean diameter 5.6 ± 0.8 cm, P = 0.0001 vs. incomplete ablation) in 135 patients were completely ablated. Nineteen patients (6.3%) developed serious complications while in hospital, including cryoshock syndrome in six patients, hepatic bleeding in five, stress-induced gastric bleeding in four, liver abscess in one and intestinal fistulas in one. Two patients died because of liver failure. The median follow-up was 36.7 months (range 6-63 months). The local tumor recurrence rate was 31%, and was related to tumor size (P = 0.029) and tumor location (P = 0.037). The mean survival duration of patients with early, intermediate and advanced HCC (Barcelona Clinic Liver Cancer staging system) was 45.7 ± 3.8, 28.4 ± 1.2 and 17.7 ± 0.6 months, respectively. CONCLUSIONS: US-guided percutaneous cryoablation is a relatively safe and effective therapy for selected HCC patients.


Assuntos
Argônio/uso terapêutico , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Criocirurgia/métodos , Hélio/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , China/epidemiologia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Ultrassonografia
12.
Clin Exp Metastasis ; 26(7): 839-48, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19784786

RESUMO

To determine the long-term prognosis of hepatocellular carcinoma (HCC) after argon-helium cryoablation and identify the risk factors that predict metastasis and recurrence. A total of 156 patients with hepatitis B-related HCC less than 5 cm in diameter who underwent curative cryoablation were followed up prospectively for tumor metastasis and recurrence. Immunohistochemistry was used to analyze the expression of vascular endothelial growth factor (VEGF). HBV basal core promoter (BCP) and precore mutations were detected by DNA sequence analysis. Post-treatment prognostic factors influencing survival, tumor metastasis and recurrence were assessed by univariate and multivariate analyses. The variables included the expression of VEGF in HCC tissues, clinical and pathologic characteristics of patients, and HBV features (HBV DNA level, HBV genotype, BCP mutation). The median follow-up period of the 156 patients was 37 months (range 8-48 months). The 1-, 2-, and 3-year overall survival rates were 92, 82 and 64%, respectively. The 1-, 2-, and 3-year recurrence-free survival rates were 72, 56 and 43%, respectively. Eighty-five patients (54.5%) had tumor recurrence or metastasis. The multivariate analysis showed that Child-Pugh class and the expression of VEGF in HCC tissues could be used as independent prognostic factors for overall survival. Meanwhile, the expression of VEGF in HCC tissues and HBV BCP mutations were found to be independent prognostic factors for recurrence-free survival. Strong expression of VEGF in HCC tissues and HBV BCP mutations are important risk predictors for recurrence or metastasis of HCC smaller than 5 cm in diameter.


Assuntos
Carcinoma Hepatocelular/patologia , Hepatite B/complicações , Neoplasias Hepáticas/patologia , Adulto , Idoso , Argônio , Sequência de Bases , Carcinoma Hepatocelular/complicações , Primers do DNA , Feminino , Hélio , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Recidiva , Taxa de Sobrevida , Fator A de Crescimento do Endotélio Vascular/genética
13.
Ai Zheng ; 28(1): 45-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19448416

RESUMO

BACKGROUND AND OBJECTIVE: Recent years, great progression has been made in treating primary hepatocellular carcinoma (HCC) with argon-helium cryosurgical ablation. This study was to evaluate its efficacy on unresectable primary HCC. METHODS: A total of 124 primary HCC patients were divided into early stage, middle stage and advanced stage groups according to BCLC staging classification. Clinical symptoms, tumor size, serum level of alpha-fetoprotein (AFP), complications, and survival time were analyzed. RESULTS: After cryoablation of the tumors, serum level of AFP was reduced in 76 (82.6%) patients, 205 (92.3%) of the 222 tumor lesions were diminished or unchanged. Untill April 2008, 14 patients survived and 110 died. The median survival time was 31.25 months in early stage group, 17.41 months in middle stage group and 6.82 months in advanced stage group. CONCLUSION: For the patients with unresectable HCC, argon-helium cryosurgical ablation has the advantages of few complications and certain efficacy.


Assuntos
Carcinoma Hepatocelular/cirurgia , Criocirurgia/métodos , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Argônio , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Criocirurgia/efeitos adversos , Feminino , Hélio , Humanos , Fígado/fisiopatologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , alfa-Fetoproteínas/análise
14.
World J Gastroenterol ; 14(5): 764-70, 2008 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-18205269

RESUMO

AIM: To determine the platelet-activating factor (PAF) synthesis and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis. METHODS: Kupffer cells, isolated from the livers of control and CCl4-induced cirrhotic rats, were placed in serum-free medium overnight. PAF saturation binding, ET-1 saturation and competition binding were assayed. ET-1 induced PAF synthesis, mRNA expression of PAF, preproendothelin-1, endothelin A (ETA) and endothelin B (ETB) receptors were also determined. RESULTS: A two-fold increase of PAF synthesis (1.42 +/- 0.14 vs 0.66 +/- 0.04 pg/microg DNA) and a 1.48-fold increase of membrane-bound PAF (1.02 +/- 0.06 vs 0.69 +/- 0.07 pg/microg DNA) were observed in activated Kupffer cells of cirrhotic rats. The application of ET-1 to Kupffer cells induced PAF synthesis in a concentration-dependent manner in both cirrhotic and normal rats via ETB receptor, but PAF synthesis in the activated Kupffer cells was more effective than that in the normal Kupffer cells. In activated Kupffer cells, PAF receptor expression and PAF binding capacity were markedly enhanced. Activated Kupffer cells raised the [125 I]-ET-1 binding capacity, but changed neither the affinity of the receptors, nor the expression of ETA receptor. CONCLUSION: Kupffer cells in the course of CCl4-induced cirrhosis are the main source of increased PAF. ET-1 is involved endogenously in stimulating the PAF synthesis in activated Kupffer cells via ETB receptor by paracrine. ETA receptor did not appear in activated Kupffer cells, which may exacerbate the hepatic and extrahepatic complications of cirrhosis.


Assuntos
Células de Kupffer/fisiologia , Cirrose Hepática/fisiopatologia , Fator de Ativação de Plaquetas/genética , Receptor de Endotelina A/genética , Receptor de Endotelina B/genética , Animais , Tetracloreto de Carbono/toxicidade , Modelos Animais de Doenças , Endotelina-1/genética , Endotelina-1/metabolismo , Células de Kupffer/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Fator de Ativação de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
15.
World J Gastroenterol ; 14(2): 218-23, 2008 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-18186558

RESUMO

AIM: To determine platelet activating factor (PAF) receptor expression in cirrhotic hepatic stellate cells. METHODS: Hepatic stellate cells, isolated from the livers of control and CCl(4)-induced cirrhotic rats, were placed in serum-free medium after overnight culture. We determined the PAF receptor in hepatic stellate cells by saturation binding technique and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), and the effects of PAF and its antagonist BN52021 on prostaglandin E(2) (PGE(2)) release by stellate cells. RESULTS: Scatchard analysis indicated the presence of PAF receptor with dissociation constant (Kd) of 4.66 nmol/L and maximum binding capacity (Bmax) of 24.65 fmol/microg in cirrhotic stellate cells. Compared with the control, the maximum PAF binding capacity increased significantly (Bmax: 24.65 +/- 1.96 fmol/microg. DNA, R = 0.982 vs 5.74 +/- 1.55 fmol/microg. DNA, R = 0.93; P < 0.01), whereas receptor affinity had no significant difference (Kd of 4.66 +/- 0.33 nmol/L for the cirrhosis and 3.51 +/- 0.26 nmol/L for the control; P > 0.05). Consistent with the receptor binding data, the mRNA expression of PAF receptor was increased significantly in cirrhotic stellate cells. PAF in a concentration-dependent manner induced PGE(2) synthesis in cirrhotic hepatic stellate cells, but the effects were blocked significantly by BN52021. CONCLUSION: Cirrhosis sensitizes hepatic stellate cells to PAF by elevating its receptor level and hepatic stellate cells maybe potential effectors of PAF induced portal hypertension.


Assuntos
Hepatócitos/fisiologia , Hipertensão Portal/metabolismo , Cirrose Hepática/metabolismo , Fator de Ativação de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Hepatócitos/patologia , Hipertensão Portal/patologia , Hipertensão Portal/fisiopatologia , Cirrose Hepática/patologia , Masculino , Glicoproteínas da Membrana de Plaquetas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética
16.
World J Gastroenterol ; 12(30): 4859-65, 2006 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16937468

RESUMO

AIM: To observe the effects of augmenter of liver regeneration (ALR) on Kupffer cells and to determine whether ALR promotes hepatocyte proliferation induced by Kupffer cells. METHODS: Kupffer cells and hepatocytes were cultured in vitro and various concentrations of recombinant rat ALR (rrALR) were added. 3H-thymidine, BrdU and 3H-leucine incorporation was determined in cultured Kupffer cells and hepatocytes, in hepatocytes conditioned by Kupffer cells, and in associated medium. rrALR was labeled by iodination and used to determine its binding activity by Scatchard analysis in Kupffer cells and primarily cultured rat hepatocytes. RESULTS: rrALR stimulated DNA replication in Kupffer cells and protein synthesis both in cells and in medium in a non-concentration-dependent manner. The effect was significant at the concentration of 1 microg/L ALR. However, rrALR had no effect on primarily cultured hepatocytes, when hepatocytes were cultured with the Kupffer cell medium conditioned by ALR, DNA replication and protein synthesis in hepatocytes increased significantly at the concentration of 1 microg/L ALR. When the ALR concentration was increased, its effect on hepatocyte proliferation decreased to the basal level. Scatchard analysis indicated the presence of a single class of high affinity receptors with a dissociation constant (Kd) of 0.883 nmol/L and a maximum binding capacity (Bmax) of 126.1 pmol/g protein in the rat Kupffer cells. CONCLUSION: ALR can promote hepatocyte proliferation induced by Kupffer cells, which is associated with the concentration of ALR, suggesting that Kupffer cells play a dual role in liver regeneration.


Assuntos
Proliferação de Células , Hepatócitos/fisiologia , Células de Kupffer/metabolismo , Regeneração Hepática/fisiologia , Proteínas/metabolismo , Animais , Células Cultivadas , Meios de Cultivo Condicionados/química , Hepatócitos/citologia , Humanos , Células de Kupffer/citologia , Masculino , Proteínas/genética , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
World J Gastroenterol ; 12(5): 709-15, 2006 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-16521183

RESUMO

AIM: To evaluate the changes in hepatic platelet activating factor (PAF) and its receptors and their effect on portal pressure of cirrhotic rats induced by CCl4. METHODS: A model of liver cirrhosis was replicated in rats by intra-peritoneal injection of CCl4 for 8 wk. We determined the effect of hepatic PAF and its receptor level on portal and arterial pressure by EIA, saturation binding and RT-PCR technique. RESULTS: Compared to control rats, cirrhotic rats had higher hepatic PAF levels and output as well as higher plasma PAF levels (P<0.01, P<0.01, P<0.05, respectively). Both hepatic PAF receptor mRNA levels and PAF binding were nearly 3-fold greater in cirrhotic rats (P<0.01). Portal injection of PAF (1 g/kg WT) increased the portal pressure by 22% and 33% in control and cirrhotic rats, respectively. In contrast, the arterial pressure was decreased in the both groups (54% in control rats and 42% in cirrhotic rats). Injection of the PAF antagonist BN52021 (5 mg/kg WT) decreased the portal pressure by 16% in cirrhotic rats but had no effect in the control rats. CONCLUSION: The upregulation of the PAF system contributes to hepatic hemodynamic and metabolic abnormalities in cirrhosis, and the increased release of PAF into the circulation has impacts on the systemic hemodynamics.


Assuntos
Hipertensão Portal/etiologia , Cirrose Hepática/complicações , Fator de Ativação de Plaquetas/fisiologia , Glicoproteínas da Membrana de Plaquetas/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Animais , Sequência de Bases , Pressão Sanguínea/efeitos dos fármacos , Tetracloreto de Carbono/toxicidade , Diterpenos/farmacologia , Ginkgolídeos , Hipertensão Portal/fisiopatologia , Lactonas/farmacologia , Fígado/fisiopatologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/fisiopatologia , Masculino , Fator de Ativação de Plaquetas/genética , Fator de Ativação de Plaquetas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
19.
Zhonghua Yi Xue Za Zhi ; 85(47): 3337-41, 2005 Dec 14.
Artigo em Chinês | MEDLINE | ID: mdl-16409839

RESUMO

OBJECTIVE: To investigate the influence of platelet activating factor (PAF) and its antagonist BN52021 on portal hypertension associated with liver cirrhosis. METHODS: Ten SD rats were injected intraperitoneally with carbon tetrachloride to establish a liver cirrhosis model and 10 rats were injected with olive oil as controls. The concentrations of PAF in the blood and liver was examined by rapid (3)H-PAF scintillation proximity assay and the hepatic PAF binding capacity was examined by receptor saturation binding technique. The pressure of portal vein and pressure of femoral artery were measured by intubation method. BN52021 was infused into the portal vein to observe its influence on the blood pressure. RESULTS: The hepatic PAF levels of the cirrhotic rats was 4.0 ng/g +/- 0.4 ng/g, significantly higher than that of the control rats (2.7 ng/g +/- 0.5 ng/g, P < 0.01). The hepatic efflux PAF level of the cirrhotic rats was 6.3 ng/g +/- 0.6 ng/g, significantly higher than that of the control rats (3.4 ng/g +/- 0.6 ng/g, P < 0.01). The hepatic output PAF levels of the cirrhotic rats was 1.0 ng/g +/- 0.6 ng/g, significantly lower than that of the control rats (0.3 ng/g +/- 0.5 ng/g, P < 0.01). The maximum PAF binding capacity of the cirrhotic rats was 2.8 +/- 0.21 fmol/microg protein, significantly higher than that of the control rats (0.9 +/- 0.06 fmol/microg protein, P < 0.01). However, the receptor affinity was not significantly different between these 2 groups. The portal pressure of the cirrhotic rats was 12.2 mm Hg +/- 0.7 mm Hg, significantly higher than that of the control rats (5.3 mm Hg +/- 0.6 mm Hg, P < 0.01). The femoral arterial pressure of the cirrhotic rats was 82 mm Hg +/- 10 mm Hg, significantly lower than that of the control rats (114 mm Hg +/- 9 mm Hg, P < 0.01). Infusion of PAF via the portal vein increased the portal pressure from 12.1 mm Hg +/- 0.6 mm Hg with an increase of 32% (P < 0.01) in the cirrhotic rats, and from 7.7 mm Hg +/- 0.8 mm Hg with an increase of 23%. The PAF response of the cirrhotic rats was 4.1 mm Hg +/- 1.0 mm Hg (227%), significantly higher than that of the control rats (1.8 mm Hg +/- 0.3 mm Hg, P < 0.01). The femoral artery pressure decreased from 82 mm Hg +/- 10 mm Hg to 48 mm Hg +/- 4 mm Hg (P < 0.01) in the cirrhotic rats, and from 114 mm Hg +/- 9 mm Hg to 52 mm Hg +/- 4 mm Hg (P < 0.01). After portal infusion of BN52021 the portal pressure decreased from 14.6 mm Hg +/- 1.6 mm Hg to 12.3 mm Hg +/- 0.8 mm Hg (P < 0.05) with a decrease of 16%, however, did not significantly influenced the femoral arterial pressure in the cirrhotic rats, and did not significantly influenced the portal pressure and femoral arterial pressure in the control rats. CONCLUSION: The increased hepatic PAF synthesis in cirrhotic is the major source of elevated circulating PAF It upregulates the hepatic hemodynamics that contributes to portal hypertension. The increased portal pressure by endogenous PAF can be decreased to a certain extent by BN52021 which may be used in treatment of portal hypertension.


Assuntos
Hipertensão Portal/metabolismo , Cirrose Hepática Experimental/metabolismo , Fator de Ativação de Plaquetas/biossíntese , Animais , Tetracloreto de Carbono/administração & dosagem , Tetracloreto de Carbono/toxicidade , Ginkgolídeos/administração & dosagem , Ginkgolídeos/farmacologia , Hipertensão Portal/etiologia , Hipertensão Portal/prevenção & controle , Injeções Intravenosas , Lactonas/administração & dosagem , Lactonas/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/complicações , Masculino , Fator de Ativação de Plaquetas/antagonistas & inibidores , Glicoproteínas da Membrana de Plaquetas/biossíntese , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
20.
World J Gastroenterol ; 10(8): 1146-51, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15069715

RESUMO

AIM: To investigate the influence of autologous cytokine-induced killer (CIK) cells on the phenotypes of CIK effector cells, peripheral T lymphocyte subsets and dendritic cell subsets in patients with primary hepatocellular carcinoma (HCC). METHODS: Peripheral blood mononuclear cells (PBMC) were collected by a blood cell separator from 13 patients with HCC, then expanded by priming them with interferon-gamma (IFN-gamma) followed by monoclonal antibody (mAb) against CD3 and interleukin-2 (IL-2) the next day. The phenotypic patterns of CIK cells were characterized by flow cytometry on d 0, 4, 7, 10, 13 and 15 of incubation, respectively. Then, 5 mL of venous blood was obtained from HCC patients before or 8-10 d after CIK cells were transfused into patients to assess the influence of CIK cells on the percentages of effector cells, and proportions of DC1 or DC2 in peripheral blood by flow cytometry. RESULTS: After two weeks of in vitro incubation, the percentages of CD3(+)CD8(+), CD3(+)CD56(+), and CD25(+) cells increased significantly from 33.5+/-10.1%, 7.7+/-2.8%, and 12.3+/-4.5% to 36.6+/-9.0% (P<0.05), 18.9+/-6.9% (P<0.01), and 16.4+/-5.9% (P<0.05), respectively. However, the percentages of CD3(+)CD4(+) and NK cells had no significant difference. The percentages of CD3(+) and CD3(+)CD8(+) cells were kept at high levels during the whole incubation period, but those of CD25(+), and CD3(+)CD56(+) cells began to decrease on d 7 and 13, respectively. The proportions of type I dendritic cell (DC1) and type II dendritic cell (DC2) subsets increased from 0.59+/-0.23% and 0.26+/-0.12% before CIK cell therapy to 0.85+/-0.27% and 0.43+/-0.19% (all P<0.01) after CIK cell transfusion, respectively. The symptoms and characteristics of HCC patients were relieved without major side effects. CONCLUSION: Our results indicated that autologous CIK cells can efficiently improve the immunological status in HCC patients, and may provide a potent approach for HCC patients as the adoptive immunotherapy.


Assuntos
Transferência Adotiva/métodos , Carcinoma Hepatocelular/terapia , Células Matadoras Naturais/transplante , Neoplasias Hepáticas/terapia , Adulto , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Complexo CD3/imunologia , Carcinoma Hepatocelular/imunologia , Feminino , Hepatite B Crônica/imunologia , Hepatite B Crônica/terapia , Hepatite B Crônica/virologia , Humanos , Imunofenotipagem , Interferon gama/farmacologia , Interleucina-2/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Neoplasias Hepáticas/imunologia , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Carga Viral
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