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1.
Virus Res ; 343: 199344, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38431054

RESUMO

BACKGROUND: Human metapneumovirus(hMPV) is one of the most common viruses that cause acute lower respiratory tract infections. Interleukin-1ß (IL-1ß) has been reported to play an important role in multiple virus replication. Patients with hMPV infection have increased levels of IL-1ß which reminds IL-1ß is associated with hMPV infection. However, the mechanism by which IL-1ß affects hMPV replication remains unclear. In this study, we explore the effect of IL-1ß on hMPV replication and investigate its specific mechanism of action. METHODS: We established an hMPV infection model through Human bronchial epithelial cells (16HBE). qRT-PCR and Western Blot were used to detect the expression levels of IL-1ß, cyclic GMP-AMP synthase (cGAS), and interferon stimulating factor (STING). Regulating IL-1ß expression by small interfering RNA (siRNA) or exogenous supplementary to study the influence of hMPV replication. The selective cGAS inhibitor RU.521, G150, and STING inhibitor H-151 were utilized to detect hMPV replication in 16HBE cells. RESULTS: The level of IL-1ß protein increased in a time-dependent and dose-dependent manner after hMPV infection. The mRNA and protein levels of cGAS and STING were significantly up-regulated. Knockdown of IL-1ß could contribute to the decreased viral loads of hMPV. While the exogenous supplement of recombinant human IL-1ß in cells, replication of hMPV was significantly increased. Additionally, the level of cGAS-STING protein expression would be affected by regulating IL-1ß expression. Inhibitors of the cGAS-STING pathway led to a lower level of hMPV replication. CONCLUSION: This study found that IL-1ß could promote hMPV replication through the cGAS-STING pathway, which has the potential to serve as a candidate to fight against hMPV infection, targeting IL-1ß may be an effective new strategy to restrain virus replication.


Assuntos
Metapneumovirus , Humanos , Metapneumovirus/genética , Interleucina-1beta/genética , Transdução de Sinais/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Interferons
2.
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
3.
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
4.
J Biomed Mater Res B Appl Biomater ; 111(7): 1407-1418, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36930047

RESUMO

Poly-γ-glutamic acid (PGA) is a naturally degradable hydrophilic linear microbial polymer with moisturizing, immunogenic, cross-linking, and hydrogel water absorption properties similar to hyaluronic acid, a biomaterial that is commonly used as a dermal filler. To explore the development feasibility of cross-linked PGA as a novel dermal filler, we studied the local skin response to PGA fillers and the effect of various cross-linking preparations on the average longevity of dermal injection. Injection site inflammation and the formation of collagen and elastin were also determined. PGA hydrogel particles prepared using 28% PGA and 10% 1,4-butanediol diglycidyl ether showed optimal filler properties, resistance to moist heat sterilization, and an average filling longevity of 94.7 ± 61.6 days in the dermis of rabbit ears. Local redness and swelling due to filler injection recovered within 14.2 ± 3.6 days. Local tissue necrosis or systemic allergic reactions were not observed, and local collagen formation was promoted. Preliminary results suggested that dermal injection of cross-linked PGA particles appeared safe and effective, suggesting that cross-linked PGA particles could be developed as a new hydrogel dermal filler.


Assuntos
Preenchedores Dérmicos , Hidrogéis , Animais , Coelhos , Materiais Biocompatíveis , Butileno Glicóis , Excipientes , Ácido Glutâmico , Ácido Hialurônico , Hidrogéis/farmacologia
5.
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
6.
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
7.
Zhongguo Zhong Yao Za Zhi ; 46(3): 703-711, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645038

RESUMO

Network Meta-analysis was used to compare the efficacy and safety of Chinese patent medicines in the treatment of unstable angina pectoris. PubMed, Cochrane Library, CNKI, Wanfang, VIP and other databases were retrieved by computers from the establishment of the databases to June 2020. Randomized controlled trials(RCTs) of Chinese patent medicines for the treatment of unstable angina pectoris were collected. Two investigators independently screened out the literatures, and extracted data according to the inclusion and exclusion criteria. The quality of the included RCTs was evaluated according to the bias risk assessment tool recommended by the Cochrane System Reviewer Manual, and the Stata 13.0 software was used for data analysis and mapping. Through screening, 28 eligible studies were finally included, with the sample size of 2 885 cases, involving 8 Chinese patent medicines. The results of the network Meta-analysis showed that in terms of total effective rate for angina symptom improvement, the order was as follows: Shenshao Capsules > Naoxintong Capsules > Ginkgo Ketone Ester Dripping Pills > Compound Danshen Dripping Pills > Ginkgo Leaf Tablets > Shexiang Baoxin Pills > Tongxinluo Capsules > Yindan Xinnaotong Soft Capsules; in terms of total effective rate for ECG curative effect, the order was as follows: Ginkgo Ketone Ester Dripping Pills>Compound Danshen Dripping Pills > Tongxinluo Capsules > Shenshao Capsules > Shexiang Baoxin Pills > Yindan Xinnaotong Soft Capsules; in terms of hypersensitivity-C-reactive protein curative effect, the order was as follows: Tongxinluo Capsules > Shenshao Capsules > Ginkgo Leaf Tablets>Compound Danshen Dropping Pills> Shexiang Baoxin Pills > Naoxintong Capsules > Yindan Xinnaotong Soft Capsules > Ginkgo Ketone Ester Dropping Pills. Chinese patent medicine combined with conventional therapy can improve the clinical efficacy of unstable angina pectoris. Due to the differences in the quantity and quality of the included studies, the order results of Chinese patent medicines need to be further verified.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional do Leste Asiático , Angina Instável/tratamento farmacológico , China , Humanos , Metanálise em Rede , Medicamentos sem Prescrição
8.
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
9.
Front Immunol ; 11: 589346, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101321

RESUMO

[This corrects the article DOI: 10.3389/fimmu.2018.01940.].

10.
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
11.
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
12.
Front Physiol ; 9: 745, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29971014

RESUMO

A pyramid strategy combining the crystal (Cry) 1A and 2A toxins in Bacillus thuringiensis (Bt) crops are active against many species of insects and nematode larvae. It has been widely used to delay pest adaption to genetically modified plants and broaden the insecticidal spectrum in many countries. Unfortunately, Cry2A can also bind with the specific receptor proteins of Cry1A. ATP-binding cassette (ABC) transporters can interact with Cry1A toxins as receptors in the insect midgut, and ABC transporter mutations result in resistance to Bt proteins. However, there is limited knowledge of the ABC transporters that specifically bind to Cry2Ab. Here, we cloned the ABCC1 gene in Helicoverpa armigera, which expressed at all larval stages and in nine different tissues. Expression levels were particularly high in fifth-instar larvae and Malpighian tubules. The two heterologously expressed HaABCC1 transmembrane domain peptides could specifically bind to Cry2Ab with high affinity levels. Moreover, transfecting HaABCC1 into the Spodoptera frugiperda nine insect cell significantly increased its mortality when exposed to Cry2Ab in vitro, and silencing HaABCC1 in H. armigera by RNA interference significantly reduced the mortality of larvae exposed to Cry2Ab in vivo. Altogether current results suggest that HaABCC1 serves as a functional receptor for Cry2Ab.

13.
Blood Adv ; 2(4): 401-413, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29472447

RESUMO

Dock8 deficiency leads to immunodeficiency, and the role of Dock8 in B-cell development and function has been revealed; however, the role of DocK8 on B-cell receptor (BCR) signaling and function of memory B cells remains elusive. In this study, we generated a Dock8 knockout mouse model and collected peripheral blood mononuclear cells from Dock8 patients to study the effect of Dock8 deficiency on the BCR signaling and activation of memory B cells with confocal microscopy and total internal reflection fluorescence microscopy. The activation of key, positive upstream BCR signaling molecules, pCD19 and phosphorylated Brutons tyrosine kinase (pBtk), is reduced. Interestingly, the total protein and activated levels of Wiskott-Aldrich syndrome protein (WASP) are decreased in Dock8-deficient mouse B cells. Our previous research has shown that WASP positively regulates cd19 transcription; furthermore, we found that Dock8 regulates cd19 transcription. What we found in Dock8 patients can be a phenotype copied from Dock8 mice. The early activation of memory B cells from Dock8 patients is disrupted with reduced BCR clustering, B-cell spreading, and signalosome recruitment into the degree of naïve B cells, as well as the transition from naïve B cells to unswitched memory B cells. Overall, our study provides a novel mechanism for Dock8 regulation of BCR signaling by regulating cd19 transcription, as well as the underlying mechanism of noncompetence of memory B cells in Dock8 patients.


Assuntos
Antígenos CD19/genética , Linfócitos B/imunologia , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Animais , Povo Asiático , Estudos de Casos e Controles , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Memória Imunológica , Ativação Linfocitária , Camundongos , Camundongos Knockout , Transcrição Gênica , Proteína da Síndrome de Wiskott-Aldrich
14.
PLoS Biol ; 15(8): e2001750, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28821013

RESUMO

As the central hub of the metabolism machinery, the mammalian target of rapamycin complex 2 (mTORC2) has been well studied in lymphocytes. As an obligatory component of mTORC2, the role of Rictor in T cells is well established. However, the role of Rictor in B cells still remains elusive. Rictor is involved in B cell development, especially the peripheral development. However, the role of Rictor on B cell receptor (BCR) signaling as well as the underlying cellular and molecular mechanism is still unknown. This study used B cell-specfic Rictor knockout (KO) mice to investigate how Rictor regulates BCR signaling. We found that the key positive and negative BCR signaling molecules, phosphorylated Brutons tyrosine kinase (pBtk) and phosphorylated SH2-containing inositol phosphatase (pSHIP), are reduced and enhanced, respectively, in Rictor KO B cells. This suggests that Rictor positively regulates the early events of BCR signaling. We found that the cellular filamentous actin (F-actin) is drastically increased in Rictor KO B cells after BCR stimulation through dysregulating the dephosphorylation of ezrin. The high actin-ezrin intensity area restricts the lateral movement of BCRs upon stimulation, consequently reducing BCR clustering and BCR signaling. The reduction in the initiation of BCR signaling caused by actin alteration is associated with a decreased humoral immune response in Rictor KO mice. The inhibition of actin polymerization with latrunculin in Rictor KO B cells rescues the defects of BCR signaling and B cell differentiation. Overall, our study provides a new pathway linking cell metablism to BCR activation, in which Rictor regulates BCR signaling via actin reorganization.


Assuntos
Actinas/metabolismo , Linfócitos B/metabolismo , Proteínas de Transporte/metabolismo , Proteínas do Citoesqueleto/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Tirosina Quinase da Agamaglobulinemia , Animais , Compostos Bicíclicos Heterocíclicos com Pontes , Membrana Celular/metabolismo , Imunidade Humoral , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Polimerização , Proteína Companheira de mTOR Insensível à Rapamicina , Tiazolidinas
15.
Blood ; 128(13): 1723-34, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27330000

RESUMO

Wiskott-Aldrich syndrome (WAS) pediatric patients exhibit a deficiency in humoral immune memory. However, the mechanism by which Wiskott-Aldrich syndrome protein (WASP) regulates the differentiation and activation of memory B cells remains elusive. Here we examine the early activation events of memory B cells from the peripheral blood mononuclear cells of WAS patients and age-matched healthy controls (HCs) using total internal reflection fluorescence microscopy. In response to stimulation through the B-cell receptor (BCR), memory B cells from HCs showed significantly higher magnitudes of BCR clustering and cell spreading than naive B cells from the same individuals. This was associated with increases in CD19 recruitment to the BCR and the activation of its downstream signaling molecule Btk and decreases in FcγRIIB recruitment and the activation of its downstream molecule Src homology 2-containing inositol 5' phosphatase (SHIP). However, these enhanced signaling activities mediated by CD19 and Btk are blocked in memory B cells from WAS patients, whereas the activation of FcγRIIB and SHIP was increased. Although the expression levels of CD19, Btk, and FcγRIIB did not change between CD27(-) and CD27(+) B cells of HCs, the protein and mRNA levels of CD19 but not Btk and FcγRIIB were significantly reduced in both CD27(-) and CD27(+) B cells of WAS patients, compared with those of HCs. Overall, our study suggests that WASP is required for memory B-cell activation, promoting the activation by positive regulating CD19 transcription and CD19 recruitment to the BCR.


Assuntos
Antígenos CD19/metabolismo , Linfócitos B/imunologia , Memória Imunológica , Síndrome de Wiskott-Aldrich/imunologia , Citoesqueleto de Actina/metabolismo , Antígenos CD19/genética , Linfócitos B/metabolismo , Estudos de Casos e Controles , Pré-Escolar , Regulação para Baixo , Humanos , Lactente , Ativação Linfocitária , Mutação , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de IgG/metabolismo , Transdução de Sinais , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética
16.
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
17.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(8): 991-993, 2016 08.
Artigo em Chinês | MEDLINE | ID: mdl-30640997

RESUMO

Now percutaneous coronary intervention (PCI) is an important treatment way for diag- nosing and treating coronary atherosclerotic heart disease (abbreviated as coronary heart disease). But use of contrast medium during intervention will result in acute renal failure. Hydration is a main measure to prevent radiographic contrast nephropathy at present. Chinese herbs play certain roles in preventing and treating radiographic contrast nephropathy. Theories of Chinese medicine hold blood stasis and toxin factor are main pathogeneses in radiographic contrast nephropathy. Therefore, blood promoting, stasis removing, and detoxification therapy is a main treatment method for preventing and treating radiographic contrast nephropathy.


Assuntos
Injúria Renal Aguda , Medicamentos de Ervas Chinesas , Intervenção Coronária Percutânea , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Meios de Contraste/efeitos adversos , Doença das Coronárias , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos
18.
Blood Adv ; 1(3): 219-230, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-29296937

RESUMO

As a key regulator of hippo signaling pathway, Mst kinases are emerging as one of the key signaling molecules that influence cell proliferation, organ size, cell migration, and cell polarity. In B lymphocytes, Mst1 deficiency causes the developmental defect of marginal zone (MZ) B cells, but how Mst1 regulates B-cell receptor (BCR) activation and differentiation remains elusive. Using genetically manipulated mouse models and total internal reflection fluorescence microscopy, we have demonstrated that Mst1 positively regulates BCR signaling via modulating CD19 transcriptional levels. Consistent with this, Mst1-deficient mice exhibited reduced BCR signaling, which is concurrent with defective BCR clustering and B-cell spreading on stimulatory lipid bilayers. The disruption of CD19-mediated Btk signaling by Mst1 deficiency leads to the severe defect in the differentiation of MZ and germinal center B cells. Mechanistic analysis showed that Mst1 upregulates the messenger RNA level of CD19 via regulating the transcriptional factor TEAD2 that directly binds to the consensus motif in the 3' untranslated region of cd19. Overall, our results reveal a new function of Mst1 in B cells and the mechanism by which Mst1 regulates the activation and differentiation of peripheral B cells.

19.
Food Chem ; 173: 718-24, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466081

RESUMO

Wolfberry (Lycium barbarum L.) fruits of three cultivars ('Damaye', 'Baihua' and 'Ningqi No.1') were harvested at five different ripening stages and evaluated for sugars and organic acids. Fructose, glucose and total sugar contents increased continually through development and reached their maxima at 34 days after full bloom (DAF). Fructose and glucose were the predominant sugars at maturity, while sucrose content had reduced by maturity. L.barbarum polysaccharides (LBP) content was in the range of 13.03-76.86 mg g(-1)FW during ripening, with a maximum at 20DAF. Citric, tartaric and quinic acids were the main organic acid components during development, and their levels followed similar trends: the highest contents were at 30, 14 and 20DAF, respectively. The significant correlations of fructose and total sugar contents with LBP content during fruit development indicated that they played a key role in LBP accumulation.


Assuntos
Carboidratos/análise , Ácidos Carboxílicos/análise , Frutas/química , Lycium/química , Ácido Cítrico/análise , Frutose/análise , Frutas/crescimento & desenvolvimento , Glucose/análise , Lycium/crescimento & desenvolvimento , Polissacarídeos/análise , Ácido Quínico/análise , Sacarose/análise , Tartaratos/análise
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