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1.
Viral Immunol ; 36(7): 449-457, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37406292

RESUMO

Respiratory virus infections are the main causes of pediatric diseases. Human metapneumovirus (hMPV) is an enveloped RNA virus similar to severe acute respiratory syndrome coronavirus type 2, both of which have emerged as important new respiratory viruses. Recent studies have found that interleukin-4 (IL-4) is involved in the replication of a variety of viruses, and its role differs in different viruses. The purpose of this study was to investigate the effect of IL-4 on hMPV and to elucidate its mechanism of action. We found that hMPV infection promoted the expression of IL-4 in human bronchial epithelial cells. The replication of the virus was reduced using small interfering RNA knockdown of IL-4 expression, while the addition of exogenous recombinant human IL-4 to IL-4 knockdown cells restored viral replication ability. These results demonstrate that the expression of IL-4 is closely related to the replication of hMPV; moreover, further experiments revealed that IL-4 promotes the replication of hMPV through a mechanism dependent on the Janus kinase/signal transductor and transcription activator 6 signaling pathway. Therefore, anti-IL-4 strategies may be a promising avenue for the treatment of hMPV infection, representing an important breakthrough for children at risk from hMPV infection.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae , Infecções Respiratórias , Criança , Humanos , Células Epiteliais/metabolismo , Interleucina-4 , Janus Quinases/metabolismo , Metapneumovirus/genética , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo
2.
Appl Environ Microbiol ; 89(7): e0062523, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37378519

RESUMO

Midgut receptors play a critical role in the specificity of Cry toxins for individual insect species. Cadherin proteins are essential putative receptors of Cry1A toxins in lepidopteran larvae. Cry2A family members share common binding sites in Helicoverpa armigera, and one of them, Cry2Aa, has been widely reported to interact with midgut cadherin. Here, we studied the binding interaction and functional role of H. armigera cadherin in the mechanism of Cry2Ab toxicity. A region spanning from cadherin repeat 6 (CR6) to the membrane-proximal region (MPR) of cadherin protein was produced as six overlapping peptides to identify the specific binding regions of Cry2Ab. Binding assays showed that Cry2Ab binds nonspecifically to peptides containing CR7 and CR11 regions in a denatured state but binds specifically only to CR7-containing peptides in the native state. The peptides CR6-11 and CR6-8 were transiently expressed in Sf9 cells to assess the functional role of cadherin. Cytotoxicity assays showed that Cry2Ab is not toxic to the cells expressing any of the cadherin peptides. However, ABCA2-expressing cells showed high sensitivity to Cry2Ab toxin. Neither increased nor decreased sensitivity to Cry2Ab was observed when the peptide CR6-11 was coexpressed with the ABCA2 gene in Sf9 cells. Instead, treating ABCA2-expressing cells with a mixture of Cry2Ab and CR6-8 peptides resulted in significantly reduced cell death compared with treatment with Cry2Ab alone. Moreover, silencing of the cadherin gene in H. armigera larvae showed no significant effect on Cry2Ab toxicity, in contrast to the reduced mortality in ABCA2-silenced larvae. IMPORTANCE To improve the efficiency of production of a single toxin in crops and to delay the evolution of insect resistance to the toxin, the second generation of Bt cotton, expressing Cry1Ac and Cry2Ab, was introduced. Understanding the mode action of the Cry proteins in the insect midgut and the mechanisms insects use to overcome these toxins plays a crucial role in developing measures to counter them. Extensive studies have been conducted on the receptors of Cry1A toxins, but relatively little has been done about those of Cry2Ab. By showing the nonfunctional binding of cadherin protein with Cry2Ab, we have furthered the understanding of Cry2Ab receptors.


Assuntos
Toxinas de Bacillus thuringiensis , Helicoverpa armigera , Proteínas de Insetos , Receptores de Superfície Celular , Helicoverpa armigera/crescimento & desenvolvimento , Helicoverpa armigera/metabolismo , Helicoverpa armigera/microbiologia , Animais , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis/metabolismo , Receptores de Superfície Celular/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Larva/metabolismo , Técnicas de Silenciamento de Genes , Células Sf9
3.
Cell Death Differ ; 29(10): 1901-1912, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35449211

RESUMO

T helper 2 (Th2) cytokine production by invariant natural killer T (iNKT) cells is involved in the development of asthma, but the regulation of Th2 cytokines in iNKT cells remains unknown. Although it is known that progranulin (PGRN) induces the production of Th2 cytokines in iNKT cells in vivo, the underlying mechanism is not clear. This study aims to investigate the role of PGRN in iNKT cells. The effects of PGRN on the differentiation of iNKT cells was detected by flow cytometry. Then stimulation of iNKT cells and airway resistance were carried out to evaluate the function of PGRN on iNKT cells. Furthermore, the mechanisms of PGRN in regulating iNKT cells was investigated by RT-PCR, WB, confocal and luciferase reporter assays. The absolute number of iNKT cells decreased in PGRN KO mice despite an increase in the percentage of iNKT cells. Furthermore, analyzing the subsets of iNKT cells, we found that NKT2 cells and their IL-4 production were reduced. Mechanistically, the decrease in NKT2 cells in the PGRN KO mice was caused by increased expression of enhancer of zeste homolog 2 (EZH2), that in turn caused increased degradation and altered nuclear localization of PLZF. Interestingly, PGRN signaling decreased expression of EZH2 and treatment of the PGRN KO mice with the EZH2 specific inhibitor GSK343 rescued the defect in NKT2 differentiation, IL-4 generation, and PLZF expression. Altogether, We have revealed a new pathway (PGRN-EZH2-PLZF), which regulates the Th2 responses of iNKT cells and provides a potentially new target for asthma treatment.


Assuntos
Asma , Proteína Potenciadora do Homólogo 2 de Zeste , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo , Animais , Diferenciação Celular , Citocinas , Interleucina-4 , Camundongos , Camundongos Endogâmicos C57BL , Progranulinas
4.
Signal Transduct Target Ther ; 6(1): 329, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471087

RESUMO

It's a challenge for detecting the therapeutic targets of a polypharmacological drug from variations in the responsed networks in the differentiated populations with complex diseases, as stable coronary heart disease. Here, in an adaptive, 31-center, randomized, double-blind trial involving 920 patients with moderate symptomatic stable angina treated by 14-day Danhong injection(DHI), a kind of polypharmacological drug with high quality control, or placebo (0.9% saline), with 76-day following-up, we firstly confirmed that DHI could increase the proportion of patients with clinically significant changes on angina-frequency assessed by Seattle Angina Questionnaire (ΔSAQ-AF ≥ 20) (12.78% at Day 30, 95% confidence interval [CI] 5.86-19.71%, P = 0.0003, 13.82% at Day 60, 95% CI 6.82-20.82%, P = 0.0001 and 8.95% at Day 90, 95% CI 2.06-15.85%, P = 0.01). We also found that there were no significant differences in new-onset major vascular events (P = 0.8502) and serious adverse events (P = 0.9105) between DHI and placebo. After performing the RNA sequencing in 62 selected patients, we developed a systemic modular approach to identify differentially expressed modules (DEMs) of DHI with the Zsummary value less than 0 compared with the control group, calculated by weighted gene co-expression network analysis (WGCNA), and sketched out the basic framework on a modular map with 25 functional modules targeted by DHI. Furthermore, the effective therapeutic module (ETM), defined as the highest correlation value with the phenotype alteration (ΔSAQ-AF, the change in SAQ-AF at Day 30 from baseline) calculated by WGCNA, was identified in the population with the best effect (ΔSAQ-AF ≥ 40), which is related to anticoagulation and regulation of cholesterol metabolism. We assessed the modular flexibility of this ETM using the global topological D value based on Euclidean distance, which is correlated with phenotype alteration (r2: 0.8204, P = 0.019) by linear regression. Our study identified the anti-angina therapeutic module in the effective population treated by the multi-target drug. Modular methods facilitate the discovery of network pharmacological mechanisms and the advancement of precision medicine. (ClinicalTrials.gov identifier: NCT01681316).


Assuntos
Angina Estável/tratamento farmacológico , Fármacos Cardiovasculares/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Adolescente , Adulto , Idoso , Angina Estável/genética , Angina Estável/patologia , Método Duplo-Cego , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
5.
Front Immunol ; 12: 794795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35116029

RESUMO

Background: The T cell receptor (TCR) diversity is essential for effective T cell immunity. Previous studies showed that TCR diversity in Wiskott-Aldrich Syndrome (WAS) patients was severely impaired, especially in the memory T cell populations. Whether this defect was caused by intrinsic WASp deficiency or extrinsic reasons is still unclear. Methods: We sorted different T cell subsets from the bone marrow chimeric mice model using both magnetic beads and flow cytometry. TCR repertoires of memory T cells, especially CD4+ effector memory T (TEM) cells and CD8+ central memory T (TCM) cells, were analyzed using the UMI quantitative high-throughput sequencing (HTS). Results: An average of 5.51 million sequencing reads of 32 samples was obtained from the Illumina sequencing platform. Bioinformatic analyses showed that compared with wild type (WT), WAS knock out (KO)-CD4+ TEM cells exhibited increased Simpson index and decreased D50 index (P <0.05); The rank abundance curve of KO-CD4+ TEM cells was shorter and steeper than that of WT, and the angle of qD and q in KO-CD4+ TEM cells was lower than that of WT, while these indexes showed few changes between WT and KO chimeric mice in the CD8+TCM population. Therefore, it indicated that the restriction on the TCRVß repertoires is majorly in KO-CD4+ TEM cells but not KO- CD8+ TCM cells. Principal Component Analysis (PCA), a comprehensive parameter for TCRVß diversity, successfully segregated CD4+ TEM cells from WT and KO, but failed in CD8+ TCM cells. Among the total sequences of TRB, the usage of TRBV12.2, TRBV30, TRBV31, TRBV4, TRBD1, TRBD2, TRBJ1.1, and TRBJ1.4 showed a significant difference between WT-CD4+ TEM cells and KO-CD4+ TEM cells (P <0.05), while in CD8+ TCM cells, only the usage of TRBV12.2 and TRBV20 showed a substantial difference between WT and KO (P <0.05). No significant differences in the hydrophobicity and sequence length of TCRVß were found between the WT and KO groups. Conclusion: WASp deficiency selectively affected the TCR diversity of different memory T cell subsets, and it had more impact on the TCRVß diversity of CD4+ TEM cells than CD8+ TCM cells. Moreover, the limitation of TCRVß diversity of CD4+ TEM cells and CD8+ TCM cells in WAS was not severe but intrinsic.


Assuntos
Células T de Memória/imunologia , Células T de Memória/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Síndrome de Wiskott-Aldrich/etiologia , Síndrome de Wiskott-Aldrich/metabolismo , Sequência de Aminoácidos , Animais , Transplante de Medula Óssea , Biologia Computacional/métodos , Modelos Animais de Doenças , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/metabolismo , Quimeras de Transplante , Recombinação V(D)J
6.
J Insect Sci ; 20(4)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32770251

RESUMO

Aphidophagous syrphids (Diptera: Syrphidae) are important insects in agroecosystems for pollination and biological control. Insect chemoreception is essential for these processes and for insect survival and reproduction; however, molecular determinants is not well understood for these beneficial insects. Here, we used recent transcriptome data for the common hoverfly, Episyrphus balteatus, to characterize key molecular components of chemoreception: odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). Six EbalCSPs and 44 EbalOBPs were cloned from this species, and sequence analysis showed that most share the characteristic hallmarks of their protein family, including a signal peptide and conserved cysteine signature. Some regular patterns and key conserved motifs of OBPs and CSPs in Diptera were identified using the online tool MEME. Motifs were also compared among the three OBP subgroups. Quantitative real-time PCR (qRT-PCR) showed that most of these chemosensory genes were expressed in chemosensory organs, suggesting these genes have chemoreceptive functions. An overall comparison of the Ka/Ks values of orthologous genes in E. balteatus and another predatory hoverfly species to analyze the evolution of these olfactory genes showed that OBPs and CSPs are under strong purifying selection. Overall, our results provide a molecular basis for further exploring the chemosensory mechanisms of E. balteatus, and consequently, may help us to understand the tritrophic interactions among plants, herbivorous insects, and natural enemies.


Assuntos
Dípteros/genética , Evolução Molecular , Proteínas de Insetos/genética , Receptores Odorantes/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Dípteros/metabolismo , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Masculino , Receptores Odorantes/química , Receptores Odorantes/metabolismo
7.
Front Immunol ; 9: 1940, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30258434

RESUMO

As a critical linker between mTORC1 and mTORC2, Akt is important for the cell metabolism. The role of Akt in the function and development of B and T cells is well characterized, however, the role of Akt for development and function of iNKT cells is unknown. iNKT cells bridge the adaptive and innate immunity, and in this study, we found that the differentiation of NKT17 cells and IL17 production of NKT17 cells were disrupted in Akt2 KO mice. ICOS has been demonstrated to be critical for the differentiation of NKT17 cells and we found that ICOS mRNA and protein expression was reduced in Akt2 KO iNKT cells. As a consequence, phosphorylation of FoxO-1 was downregulated in Akt2 KO thymocytes but the sequestration of FoxO-1 in the nucleus of Akt2 KO iNKT cells was increased. The negative feedback loop between ICOS and FoxO-1 has been demonstrated in CD4+T follicular helper cells. Therefore our study has revealed a new intracellular mechanism in which Akt2 regulates ICOS expression via FoxO-1 and this signaling axis regulates the differentiation and function of NKT17 cells. This study provides a new linker between cell metabolism and function of iNKT cells.


Assuntos
Diferenciação Celular/imunologia , Proteína Forkhead Box O1/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Células T Matadoras Naturais/imunologia , Proteínas Proto-Oncogênicas c-akt/imunologia , Transdução de Sinais/imunologia , Animais , Diferenciação Celular/genética , Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/citologia , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genética
8.
Blood ; 127(25): 3180-91, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27170596

RESUMO

Wiskott-Aldrich syndrome protein (WASp) is a hematopoietic-specific regulator of actin nucleation. Wiskott-Aldrich syndrome (WAS) patients show immunodeficiencies, most of which have been attributed to defective T-cell functions. T follicular helper (Tfh) cells are the major CD4(+) T-cell subset with specialized B-cell helper capabilities. Aberrant Tfh cells activities are involved in immunopathologies such as autoimmunity, immunodeficiencies, and lymphomas. We found that in WAS patients, the number of circulating Tfh cells was significantly reduced due to reduced proliferation and increased apoptosis, and Tfh cells were Th2 and Th17 polarized. The expression of inducible costimulator (ICOS) in circulating Tfh cells was higher in WAS patients than in controls. BCL6 expression was decreased in total CD4(+) T and Tfh cells of WAS patients. Mirroring the results in patients, the frequency of Tfh cells in WAS knockout (KO) mice was decreased, as was the frequency of BCL6(+) Tfh cells, but the frequency of ICOS(+) Tfh cells was increased. Using WAS chimera mice, we found that the number of ICOS(+) Tfh cells was decreased in WAS chimera mice, indicating that the increase in ICOS(+) Tfh cells in WAS KO mice was cell extrinsic. The data from in vivo CD4(+) naive T-cell adoptive transfer mice as well as in vitro coculture of naive B and Tfh cells showed that the defective function of WASp-deficient Tfh cells was T-cell intrinsic. Consistent findings in both WAS patients and WAS KO mice suggested an essential role for WASp in the development and memory response of Tfh cells and that WASp deficiency causes a deficient differentiation defect in Tfh cells by downregulating the transcription level of BCL6.


Assuntos
Centro Germinativo/patologia , Linfócitos T Auxiliares-Indutores/patologia , Linfócitos T Auxiliares-Indutores/fisiologia , Síndrome de Wiskott-Aldrich/imunologia , Animais , Linfócitos B , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/fisiologia , Estudos de Casos e Controles , Diferenciação Celular , Células Cultivadas , Centro Germinativo/imunologia , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Interleucinas/metabolismo , Linfonodos/imunologia , Linfonodos/patologia , Camundongos , Camundongos Knockout , Fator 1 de Ligação ao Domínio I Regulador Positivo , Receptores CXCR5/metabolismo , Proteínas Repressoras/metabolismo , Síndrome de Wiskott-Aldrich/sangue , Síndrome de Wiskott-Aldrich/patologia , Proteína da Síndrome de Wiskott-Aldrich/genética
9.
Zhongguo Fei Ai Za Zhi ; 10(4): 284-7, 2007 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-21122294

RESUMO

BACKGROUND: It has been proven that clusterin is a newly apoptosis-related factor and upregulates in many tumors. It plays important roles in carcinogenesis and tumor progression. The antiapoptosis of clusterin seems to be relative to other antiapoptosis factors. The aim of this study is to investigate the expression and significance of clusterin in non-small cell lung cancer (NSCLC) tissue. METHODS: The expression of clusterin, p53 and Bax in NSCLC were detected by immunohistochemical SP method and Western blot assay. RESULTS: Positive expression rate of clusterin was 79.25% (42/53) in NSCLC tissues which was much higher than that in normal lung tissue (2/16, 12.50%) (Chi-square=23.68, P < 0.05). The expression of clusterin was closely related to pathological differentiation (rs=0.464, P < 0.01), clinical stage (rs =0.320, P < 0.01) and lymph node metastasis (rs=0.255, P < 0.05), but not correlated to the sex (Chi-square=0.007, P > 0.05), age (Chi-square=0.707, P > 0.05) and histological type (Chi-square=0.702, P > 0.05). The expression of clusterin in NSCLC was positively correlated to the expression of p53 (rs=0.589, P < 0.01), but was negatively related to the expression of Bax (rs =-0.346, P < 0.01). The relative expression level of clusterin protein in NSCLC was significantly higher than that in normal lung tissue (0.541±0.010 vs 0.201±0.020) (P < 0.05). CONCLUSIONS: Clusterin may play an important role in the biological characteristics of NSCLC by the antiapoptosis pathway.

10.
Zhonghua Zhong Liu Za Zhi ; 28(4): 253-6, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16875621

RESUMO

OBJECTIVE: To analyze the drug-sensitivity-related genes to anti-tumor drugs navalbine (NVB) and docetaxel (Doc) in four SCLC and six NSCLC cell lines. METHODS: The sensitivity of 4 SCLC lines and 6 NSCLC lines to NVB and to Doc was determined with MTT test. The expression of 1291 anti-tumor drug sensitivity-related genes in the 10 cell lines was assayed by cDNA macroarray technique, and cluster analysis was performed to find the relationship between the results obtained by the above mentioned two measurements. RESULTS: (1) The anti-tumor effect of NVB on the 10 cell lines was apparently better than that of Doc. (2) The drug sensitivity-related genes in these 10 cell lines showed a more close positive correlation with Doc than that with NVB, whereas more genes showed negative correlation with NVB than that with Doc. But in 6 NSCLC cell lines, more genes showed the same positive or negative correlation with the two drugs. (3) 51 genes in the 10 cell lines showed correlation with Doc or NVB. 13 of them had negative correlation with Doc, 11 of them showed positive correlation. 24 of them showed negative correlation with NVB, 3 of them showed positive correlation. 67 genes in 6 NSCLC cell lines showed a correlation with sensitivity to Doc or NVB, among them 34 had negative correlation with Doc, 4 had positive correlation. 25 genes had negative correlation with NVB, 4 had positive correlation. (4) Rab 1, Rab 3, Rho B, Rho C, Rac 1, Rac 2, Gho GDI beta, CD44, integrin alpha5, integrin alpha6, integrin beta5, vinculin showed to be cytoskeleton-related genes differently expressing in SCLC or NSCLC cell lines. CONCLUSION: There is obvious difference in the drug sensitivity-related genes to NVB or Doc between SCLC and NSCLC cell lines.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , Taxoides/farmacologia , Vimblastina/análogos & derivados , Linhagem Celular Tumoral , Análise por Conglomerados , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/genética , Docetaxel , Perfilação da Expressão Gênica , Humanos , Integrina alfa5/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Vimblastina/farmacologia , Vinorelbina , Proteínas rab1 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
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