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1.
Blood ; 143(2): 166-177, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-37871574

RESUMO

ABSTRACT: Persisting alloreactive donor T cells in target tissues are a determinant of graft-versus-host disease (GVHD), but the transcriptional regulators that control the persistence and function of tissue-infiltrating T cells remain elusive. We demonstrate here that Id3, a DNA-binding inhibitor, is critical for sustaining T-cell responses in GVHD target tissues in mice, including the liver and intestine. Id3 loss results in aberrantly expressed PD-1 in polyfunctional T helper 1 (Th1) cells, decreased tissue-infiltrating PD-1+ polyfunctional Th1 cell numbers, impaired maintenance of liver TCF-1+ progenitor-like T cells, and inhibition of GVHD. PD-1 blockade restores the capacity of Id3-ablated donor T cells to mediate GVHD. Single-cell RNA-sequencing analysis revealed that Id3 loss leads to significantly decreased CD28- and PI3K/AKT-signaling activity in tissue-infiltrating polyfunctional Th1 cells, an indicator of active PD-1/PD-L1 effects. Id3 is also required for protecting CD8+ T cells from the PD-1 pathway-mediated suppression during GVHD. Genome-wide RNA-sequencing analysis reveals that Id3 represses transcription factors (e.g., Nfatc2, Fos, Jun, Ets1, and Prdm1) that are critical for PD-1 transcription, exuberant effector differentiation, and interferon responses and dysfunction of activated T cells. Id3 achieves these effects by restraining the chromatin accessibility for these transcription factors. Id3 ablation in donor T cells preserved their graft vs tumor effects in mice undergoing allogeneic hematopoietic stem cell transplantation. Furthermore, CRISPR/Cas9 knockout of ID3 in human CD19-directed chimeric antigen receptor T cells retained their antitumor activity in NOD/SCID/IL2Rg-/- mice early after administration. These findings identify that ID3 is an important target to reduce GVHD, and the gene-editing program of ID3 may have broad implications in T-cell-based immunotherapy.


Assuntos
Doença Enxerto-Hospedeiro , Receptor de Morte Celular Programada 1 , Camundongos , Animais , Humanos , Receptor de Morte Celular Programada 1/genética , Fosfatidilinositol 3-Quinases , Camundongos SCID , Camundongos Endogâmicos NOD , Doença Enxerto-Hospedeiro/prevenção & controle , Fatores de Transcrição , RNA
2.
Blood ; 141(9): 1070-1086, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36356302

RESUMO

Intestinal epithelial cells (IECs) are implicated in the propagation of T-cell-mediated inflammatory diseases, including graft-versus-host disease (GVHD), but the underlying mechanism remains poorly defined. Here, we report that IECs require receptor-interacting protein kinase-3 (RIPK3) to drive both gastrointestinal (GI) tract and systemic GVHD after allogeneic hematopoietic stem cell transplantation. Selectively inhibiting RIPK3 in IECs markedly reduces GVHD in murine intestine and liver. IEC RIPK3 cooperates with RIPK1 to trigger mixed lineage kinase domain-like protein-independent production of T-cell-recruiting chemokines and major histocompatibility complex (MHC) class II molecules, which amplify and sustain alloreactive T-cell responses. Alloreactive T-cell-produced interferon gamma enhances this RIPK1/RIPK3 action in IECs through a JAK/STAT1-dependent mechanism, creating a feed-forward inflammatory cascade. RIPK1/RIPK3 forms a complex with JAK1 to promote STAT1 activation in IECs. The RIPK1/RIPK3-mediated inflammatory cascade of alloreactive T-cell responses results in intestinal tissue damage, converting the local inflammation into a systemic syndrome. Human patients with severe GVHD showed highly activated RIPK1 in the colon epithelium. Finally, we discover a selective and potent RIPK1 inhibitor (Zharp1-211) that significantly reduces JAK/STAT1-mediated expression of chemokines and MHC class II molecules in IECs, restores intestinal homeostasis, and arrests GVHD without compromising the graft-versus-leukemia (GVL) effect. Thus, targeting RIPK1/RIPK3 in IECs represents an effective nonimmunosuppressive strategy for GVHD treatment and potentially for other diseases involving GI tract inflammation.


Assuntos
Doença Enxerto-Hospedeiro , Intestinos , Camundongos , Humanos , Animais , Mucosa Intestinal/metabolismo , Inflamação/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/metabolismo , Homeostase , Proteína Serina-Treonina Quinases de Interação com Receptores
3.
Brain ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963812

RESUMO

The medial prefrontal cortex (mPFC) has been implicated in the pathophysiology of social impairments including social fear. However, the precise subcortical partners that mediate mPFC dysfunction on social fear behaviour have not been identified. Employing a social fear conditioning paradigm, we induced robust social fear in mice and found that the lateral habenula (LHb) neurons and LHb-projecting mPFC neurons are synchronously activated during social fear expression. Moreover, optogenetic inhibition of the mPFC-LHb projection significantly reduced social fear responses. Importantly, consistent with animal studies, we observed an elevated prefrontal-habenular functional connectivity in subclinical individuals with higher social anxiety characterized by heightened social fear. These results unravel a crucial role of the prefrontal-habenular circuitry in social fear regulation and suggest that this pathway could serve as a potential target for the treatment of social fear symptom often observed in many psychiatric disorders.

4.
Nature ; 567(7748): 409-413, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30867599

RESUMO

Chromatin remodellers include diverse enzymes with distinct biological functions, but nucleosome-sliding activity appears to be a common theme1,2. Among the remodelling enzymes, Snf2 serves as the prototype to study the action of this protein family. Snf2 and related enzymes share two conserved RecA-like lobes3, which by themselves are able to couple ATP hydrolysis to chromatin remodelling. The mechanism by which these enzymes couple ATP hydrolysis to translocate the nucleosome along the DNA remains unclear2,4-8. Here we report the structures of Saccharomyces cerevisiae Snf2 bound to the nucleosome in the presence of ADP and ADP-BeFx. Snf2 in the ADP-bound state adopts an open conformation similar to that in the apo state, and induces a one-base-pair DNA bulge at superhelix location 2 (SHL2), with the tracking strand showing greater distortion than the guide strand. The DNA distortion propagates to the proximal end, leading to staggered translocation of the two strands. The binding of ADP-BeFx triggers a closed conformation of the enzyme, resetting the nucleosome to a relaxed state. Snf2 shows altered interactions with the DNA in different nucleotide states, providing the structural basis for DNA translocation. Together, our findings suggest a fundamental mechanism for the DNA translocation that underlies chromatin remodelling.


Assuntos
Adenosina Trifosfatases/metabolismo , Montagem e Desmontagem da Cromatina , Cromatina/genética , Cromatina/metabolismo , DNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae , Fatores de Transcrição/metabolismo , Difosfato de Adenosina/química , Difosfato de Adenosina/metabolismo , Adenosina Trifosfatases/química , Apoproteínas/química , Apoproteínas/metabolismo , Transporte Biológico , Cromatina/química , DNA/química , DNA/genética , Transferência Ressonante de Energia de Fluorescência , Modelos Moleculares , Nucleossomos/química , Nucleossomos/metabolismo , Nucleotídeos/química , Nucleotídeos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Fatores de Transcrição/química
5.
Ann Surg Oncol ; 31(2): 860-871, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947979

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy (NCRT) is recommended as the treatment standard for locally advanced esophageal squamous cell carcinoma (ESCC). The use of immunotherapy in the neoadjuvant setting has gained attention. Multiple, clinical trials have explored the efficacy and safety of neoadjuvant immunochemotherapy (NICT). We evaluated the differences in clinicopathologic outcomes and the patterns of lymphatic spread among patients receiving neoadjuvant chemotherapy (NCT), NCRT, and NICT before esophagectomy for locally advanced ESCC. METHODS: A total of 702 patients with ESCC who completed transthoracic esophagectomy followed neoadjuvant therapy were included. Pathological characteristics, including pathologic complete response (pCR), tumor regression grade (TRG) score and patterns of lymphatic spread, were evaluated. RESULTS: Compared with the NCT group, the NCRT group and NICT group had an advantage in pathological response (P < 0.05). The pCR rate was 8.1% in the NCT group, 29.9% in the NCRT group, and 23.6% in the NICT group. The TRG score (P < 0.05) and pathologic T stage (P < 0.05) in the NCT group were significantly higher. Compared with NICT, NCRT can significantly reduce the rate of lymph node metastasis rate in station 1R (0 vs. 3.4%, P < 0.05) and 2R (1.1% vs. 6.8%, P < 0.05). Subgroup analysis according to the tumor location distribution showed that NICT group had higher lymph node metastasis rate in station 2R (9.1%) in middle thoracic cases (P < 0.05) and in station 18 (7.5%) (P < 0.05) in lower thoracic cases. CONCLUSIONS: NCRT or NICT followed by surgery may result in a promising pCR rate and show a better performance in therapeutic response of primary lesion. For patients with lymph node metastasis in station 1R and 2R, NCRT should be the optimal preoperative treatment strategy.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Terapia Neoadjuvante , Neoplasias Esofágicas/patologia , Metástase Linfática , Quimiorradioterapia , Imunoterapia , Esofagectomia
6.
J Chem Phys ; 160(17)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38748016

RESUMO

The impacting phenomenon of nanodroplets has received much attention due to their importance in various industrial applications. The oblique impingement of single droplets is well understood; however, the effect of oblique angle on impacting the dynamics of multiple droplets at the nanoscale is very limited. To address this gap, we perform molecular dynamics (MD) simulations to study the impacting dynamics of binary nanodroplets with various oblique angles (αob) and Weber numbers (We). Using MD simulations, we directly capture the detailed morphological evolution of the impacting binary droplets with various given conditions. Compared to the oblique impingement of a single droplet, the evolution of impacting binary droplets involves two novel dynamic characteristics: the asymmetric dynamics with droplet preferential spreading in the y direction and the rotating of the coalescing droplet. The mechanisms underlying are well studied. The asymmetric dynamics is a result of the velocity gradient of the outer edge of the spreading droplet, and the rotating effect is due to the change in angular momentum induced by surface force. The analysis and study of these phenomena have never been mentioned in previous studies of single droplet. Finally, we investigate the effect of αob and We on normalized moving distance (L/Dsin) and contact time (tc). This work paves the way for offering a comprehensive understanding of the oblique impingement of binary nanodroplets.

7.
Physiol Genomics ; 55(1): 27-40, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36440907

RESUMO

Pectic polysaccharides (PPs) could exert functions on ulcerative colitis (UC), which is classified as a nonspecific inflammatory disorder. This study investigated the molecular mechanism of PPs derived from Rauwolfia in UC. First, the dextran sodium sulfate (DSS)-induced mouse colitis models and lipopolysaccharide (LPS)-treated colonic epithelial cell (YAMC) models were established and treated with PP. Subsequently, the effects of PPs on mucosal damages in DSS mice were detected, and the levels of inflammatory cytokines, pyroptosis-related factors, oxidative stress-related markers, and the tight junction-related proteins in the tissues or cells were examined, and the results suggested that PPs ameliorated colonic mucosal damages and cell pyroptosis in DSS mice, and limited colonic epithelial cell pyroptosis in in vitro UC models. Subsequently, the binding relations of retinol-binding protein 4 (RBP4) to miR-124-3p and NLR pyrin domain-containing 3 (NLRP3) were analyzed. miR-124-3p targeted RBP4 and reduced the binding of RBP4 to NLRP3, thus inhibiting NLRP3-mediated pyroptosis. Finally, functional rescue experiments revealed that miR-124-3p suppression or RBP4 overexpression promoted colonic epithelial cell pyroptosis. Collectively, Rauwolfia-derived PPs limited miR-124-3p and targeted RBP4 and reduced the binding potency of RBP4 to NLRP3 to inhibit NLRP3-mediated pyroptosis, resulting in the alleviation of colonic epithelial cell pyroptosis and mucosal damages in UC.


Assuntos
Colite Ulcerativa , Colite , MicroRNAs , Rauwolfia , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Rauwolfia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pectinas/efeitos adversos , Piroptose , Domínio Pirina , Colite/induzido quimicamente , Células Epiteliais/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
8.
Nanotechnology ; 34(31)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37116476

RESUMO

Last decades have witnessed the rapid development of ultraviolet (UV) photodetectors in diversity of applications. The III-nitride semiconductor and metal halide perovskite have both performed promising UV-sensing optoelectronic properties. However, they are still suffering from either the high temperature epitaxial-growth or low photocurrent generated in UV range. In this work, we demonstrate an innovative MAPbCl3/GaN particle hybrid device with all-solution-processed deposition methods. Comparing to the control MAPbCl3photoconductors, the photo-sensing ability of the hybrid device with the optimal concentration of GaN particles is more than one order of magnitude enhanced, and report a responsivity of 86 mA W-1, a detectivity of 3.1 × 1011Jones and a rise/fall time of 1.1/10.7 ms at 360 nm. The photocurrent increment could be attributed to the enhanced UV absorption of GaN particles and facilitated charge separation and photoconductive gain at MAPbCl3/GaN heterojunction. This work paves a pathway towards the large-scale low-cost UV photodetectors in versatile applications.

9.
Sensors (Basel) ; 23(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38067723

RESUMO

The global concern regarding the monitoring of construction workers' activities necessitates an efficient means of continuous monitoring for timely action recognition at construction sites. This paper introduces a novel approach-the multi-scale graph strategy-to enhance feature extraction in complex networks. At the core of this strategy lies the multi-feature fusion network (MF-Net), which employs multiple scale graphs in distinct network streams to capture both local and global features of crucial joints. This approach extends beyond local relationships to encompass broader connections, including those between the head and foot, as well as interactions like those involving the head and neck. By integrating diverse scale graphs into distinct network streams, we effectively incorporate physically unrelated information, aiding in the extraction of vital local joint contour features. Furthermore, we introduce velocity and acceleration as temporal features, fusing them with spatial features to enhance informational efficacy and the model's performance. Finally, efficiency-enhancing measures, such as a bottleneck structure and a branch-wise attention block, are implemented to optimize computational resources while enhancing feature discriminability. The significance of this paper lies in improving the management model of the construction industry, ultimately aiming to enhance the health and work efficiency of workers.


Assuntos
Indústria da Construção , Sistema Musculoesquelético , Humanos , Esqueleto , , Extremidade Inferior
10.
Int J Mol Sci ; 24(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38069077

RESUMO

Propolis is a gelatinous substance processed by western worker bees from the resin of plant buds and mixed with the secretions of the maxillary glands and beeswax. Propolis has extensive biological activities and antitumor effects. There have been few reports about the antitumor effect of propolis against human cutaneous squamous cell carcinoma (CSCC) A431 cells and its potential mechanism. CCK-8 assays, label-free proteomics, RT-PCR, and a xenograft tumor model were employed to explore this possibility. The results showed that the inhibition rate of A431 cell proliferation by the ethanol extract of propolis (EEP) was dose-dependent, with an IC50 of 39.17 µg/mL. There were 193 differentially expressed proteins in the EEP group compared with the control group (p < 0.05), of which 103 proteins (53.37%) were upregulated, and 90 proteins (46.63%) were downregulated. The main three activated and suppressed Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were extracellular matrix (ECM)-receptor interaction, amoebiasis, cell adhesion molecules (CAMs), nonalcoholic fatty liver disease (NAFLD), retrograde endocannabinoid signaling, and Alzheimer's disease. The tumor volume of the 100 mg/kg EEP group was significantly different from that of the control group (p < 0.05). These results provide a theoretical basis for the potential treatment of human CSCC A431 cell tumors using propolis.


Assuntos
Carcinoma de Células Escamosas , Própole , Neoplasias Cutâneas , Humanos , Linhagem Celular Tumoral , Própole/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Extratos Vegetais/farmacologia , Etanol/farmacologia , Proliferação de Células
11.
Cell Immunol ; 382: 104631, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36272268

RESUMO

Hepatitis is closely related to cirrhosis and liver cancer, and it is vital that we develop new drugs and identify new drug targets. Traditional Chinese medicine has demonstrated excellent curative effects on liver diseases. The ingredients from Chinese herbals are important source for drug development in the treatment of hepatitis. Here, we found that narciclasine (NCS), a major component extracted from narcissus bulbs, showed hepatoprotective effect against concanavalin A (Con A) induced hepatitis. NCS treatment significantly reduced hepatocyte death, hepatic inflammatory cells infiltration, and serum cytokine levels in Con A challenged mice. We further observed that NCS directly inhibited Con A induced splenocytes proliferation and cytokine production in vitro. RNA-seq results showed that genes related to immune response were upregulated in Con A treated CD4+ T cells, which were down-regulated in the presence of NCS. Moreover, the AMPK pathway had been found activated in response to NCS treatment, suggesting a potential target for NCS targets. In conclusion, our results reveal that NCS is a powerful immunosuppressor against T cell activation, thus leading to protection against Con A induced liver injury in mice. These findings provide new insights into the use of natural products in the treatment of autoimmune hepatitis.


Assuntos
Proteínas Quinases Ativadas por AMP , Linfócitos T , Camundongos , Animais , Proteínas Quinases Ativadas por AMP/farmacologia , Concanavalina A , Fígado , Citocinas , Camundongos Endogâmicos C57BL
12.
Arch Microbiol ; 204(7): 449, 2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35779121

RESUMO

A Gram-positive, motile, rod-shaped and lignin-degrading novel actinomycete, designated strain NEAU-YY56T, was isolated from the rhizosphere soil of wheat (Triticum aestivum L.) collected from Zhumadian, Henan Province, Central China and characterized using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain NEAU-YY56T belonged to the genus Cellulomonas and exhibited 16S rRNA gene sequence similarities of 98.7, 98.2 and 98.1% to Cellulomonas pakistanensis JCM 18755T, Cellulomonas denverensis JCM 14733T and Cellulomonas hominis JCM 12133T, respectively. The whole-cell sugars were glucose, rhamnose and ribose. The peptidoglycan of strain NEAU-YY56T contained ornithine and glutamic acid. The phospholipid profile was found to contain diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and two unknown glycolipids. The major menaquinone was MK-9(H4). The major fatty acids (> 5.0%) were identified as anteiso-C15:0, C16:0, C14:0 and anteiso-C17:0. Meanwhile, DNA G+C content was 74.7%. The morphological and chemotaxonomic properties of strain NEAU-YY56T were also confirmed the affiliation of the isolate to the genus Cellulomonas. However, physiological and biochemical characteristics indicated that strain NEAU-YY56T can be clearly differentiated from its closest relatives. In addition, the ANI values and dDDH levels between strain NEAU-YY56T and related Cellulomonas species were lower than the accepted threshold value. Therefore, it is concluded that strain NEAU-YY56T represents a novel species of the genus Cellulomonas, for which the name Cellulomonas triticagri sp. nov. is proposed. The type strain is NEAU-YY56T (= DSM 106717T = JCM 32550T).


Assuntos
Cellulomonas , Rizosfera , Técnicas de Tipagem Bacteriana , Cellulomonas/genética , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo/química , Microbiologia do Solo , Triticum
13.
EMBO Rep ; 21(5): e48904, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32212315

RESUMO

While the zinc finger transcription factors EGR1, EGR2, and EGR3 are recognized as critical for T-cell function, the role of EGR4 remains unstudied. Here, we show that EGR4 is rapidly upregulated upon TCR engagement, serving as a critical "brake" on T-cell activation. Hence, TCR engagement of EGR4-/- T cells leads to enhanced Ca2+ responses, driving sustained NFAT activation and hyperproliferation. This causes profound increases in IFNγ production under resting and diverse polarizing conditions that could be reversed by pharmacological attenuation of Ca2+ entry. Finally, an in vivo melanoma lung colonization assay reveals enhanced anti-tumor immunity in EGR4-/- mice, attributable to Th1 bias, Treg loss, and increased CTL generation in the tumor microenvironment. Overall, these observations reveal for the first time that EGR4 is a key regulator of T-cell differentiation and function.


Assuntos
Sinalização do Cálcio , Fatores de Transcrição de Resposta de Crescimento Precoce , Neoplasias , Animais , Diferenciação Celular , Ativação Linfocitária , Camundongos , Microambiente Tumoral , Dedos de Zinco
14.
Nature ; 540(7633): 466-469, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27919072

RESUMO

ISWI is a member of the SWI2/SNF2 family of chromatin remodellers, which also includes Snf2, Chd1, and Ino80. ISWI is the catalytic subunit of several chromatin remodelling complexes, which mobilize nucleosomes along genomic DNA, promoting replication progression, transcription repression, heterochromatin formation, and many other nuclear processes. The ATPase motor of ISWI is an autonomous remodelling machine, whereas its carboxy (C)-terminal HAND-SAND-SLIDE (HSS) domain functions in binding extranucleosomal linker DNA. The activity of the catalytic core of ISWI is inhibited by the regulatory AutoN and NegC domains, which are in turn antagonized by the H4 tail and extranucleosomal DNA, respectively, to ensure the appropriate chromatin landscape in cells. How AutoN and NegC inhibit ISWI and regulate its nucleosome-centring activity remains elusive. Here we report the crystal structures of ISWI from the thermophilic yeast Myceliophthora thermophila and its complex with a histone H4 peptide. Our data show the amino (N)-terminal AutoN domain contains two inhibitory elements, which collectively bind the second RecA-like domain (core2), holding the enzyme in an inactive conformation. The H4 peptide binds to the core2 domain coincident with one of the AutoN-binding sites, explaining the ISWI activation by H4. The H4-binding surface is conserved in Snf2 and functions beyond AutoN regulation. The C-terminal NegC domain is involved in binding to the core2 domain and functions as an allosteric element for ISWI to respond to the extranucleosomal DNA length.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/química , Sordariales/química , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/química , Adenosina Trifosfatases/metabolismo , Regulação Alostérica , Sítios de Ligação , Domínio Catalítico , Montagem e Desmontagem da Cromatina , Cristalografia por Raios X , Ativação Enzimática , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Histonas/química , Histonas/metabolismo , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Recombinases Rec A/química , Fatores de Transcrição/metabolismo
15.
Appl Microbiol Biotechnol ; 106(3): 1151-1164, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35037999

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that causes the coronavirus disease (COVID-19). It is confirmed that nucleocapsid (N) protein is closely related to viral pathogenesis, modulation of host immune response, RNA transcription, and replication and virus packaging. Therefore, the N protein is a preponderant antigen target for virus detection. The codon-optimized N gene was designed according to the encoding characteristics of insect cells and inserted into pFastBacTM1 vector with 6 × His-tag-fused N protein for expression in insect sf21 cells. Six anti-N mAbs (4G3, 5B3, 12B6, 18C7-A2, 21H10-A3, 21H10-E9) were prepared by recombinant N protein. The mAbs showed high titers, antibody affinity, and reactivity with the SARS-CoV-2 N protein. Then, fourteen overlapped peptides that covered the intact N protein were synthesized (N1-N14). Peptide N14 was identified as the main linear B-cell epitope region via peptide-ELISA and dot-blot assay, and this region was truncated gradually until mapping the peptide 401-DFSKQLQQ-408. Simultaneously, compared with the sequence of variants of concern (VOCs) and variants of interest (VOIs) strains among the several countries, epitope 401-DFSKQLQQ-408 is very conservative among them. The findings provide new guidance for the design and detection of COVID-19 targets. KEY POINTS: • The N protein was optimized according to the insect cell codon preference and was highly expressed. • The monoclonal antibodies prepared in this study were shown high antibody titers and high affinity. • Monoclonal antibodies were used to map the epitope 401-408 amino acids of N protein for the first time in this study.


Assuntos
COVID-19 , Proteínas do Nucleocapsídeo , Anticorpos Monoclonais , Anticorpos Antivirais , Mapeamento de Epitopos , Epitopos de Linfócito B , Humanos , Proteínas do Nucleocapsídeo/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
16.
Mol Carcinog ; 60(8): 524-537, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34038586

RESUMO

Tumour-derived CXCL8 facilitates the movement of myeloid-derived suppressor cells, which are able to restrain antitumour immune responses to the tumour microenvironment. Kruppel-like factor 4 (KLF4) is a potential tumour suppressor in gastric cancer (GC). However, knowledge regarding correlations between KLF4 and CXCL8 in GC is limited. We use cellular and molecular biological methods to assess whether these two factors interact in GC. Expression CXCL8 and KLF4 was altered in human GC tissues compared to normal gastric tissues in opposite ways. Additionally, cytotoxin-associated gene A protein (CagA) gene transduction or Helicobacter pylori (H. pylori) infection upregulated CXCL8 expression. Knockdown of KLF4 expression increased CXCL8 protein and RNA expression, whereas its overexpression had the opposite effect. CXCL8-mediated enhancement of GC cell migration and proliferation was reversed by upregulation of KLF4 expression. Further mechanistic research revealed that KLF4 binds the CXCL8 promoter, suppressing CXCL8 transcription. Moreover, CXCL8 stimulation reduced KLF4 protein expression and promoted GC cell proliferation and migration, eventually promoting neoplasm growth in vivo. Together, our findings demonstrate that CagA promotes CXCL8 and inhibits KLF4. CXCL8 is a decisive downstream target gene of KLF4, and KLF4 negatively regulates CXCL8 in GC. Furthermore, CXCL8's negative regulation of KLF4 in vivo and in vitro, indicates that CagA may downregulate KLF4 by inducing CXCL8 expression, low expression of KLF4 further promotes that of CXCL8, forming a vicious circle in GC. Targeted KLF4 activation might improve the immunosuppressive microenvironment through direct negative regulation of CXCL8, providing a new potential target to strengthen the efficacy of immunotherapy in GC patients.


Assuntos
Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/fisiologia , Interleucina-8/genética , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Gástricas/etiologia , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Infecções por Helicobacter/complicações , Humanos , Fator 4 Semelhante a Kruppel , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Microambiente Tumoral
17.
Toxicol Appl Pharmacol ; 427: 115654, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34310909

RESUMO

Diabetic cardiomyopathy (DCM) is a serious diabetic complication that lacks effective preventive or therapeutic approaches. Wild-type and Klf15 knockout (Klf15-KO) mice were fed with either high fat diet (HFD, 60% kcal from fat) or normal diet (ND, 10% kcal from fat) for 3 months and then injected with streptozotocin or vehicle, to induce type 2 diabetes (T2D). All T2D and age-matched control mice were treated with or without SDF-1ß at 5 mg/kg body-weight twice a week and also continually received HFD or ND for 3 months. At the end of 6-month study, after cardiac functions were measured, mice were euthanized to collect heart tissue. For in vitro mechanistic study, H9c2 cells were exposed to palmitate to mimic in vivo condition of T2D. SDF-1ß prevented T2D-induced cardiac dysfunction and fibrosis and T2D-down-regulated KLF15 expression in wild-type diabetic heart tissue. However, the preventive effects of SDF-1ß on both KLF15 expression and fibrosis was abolished, with partial cardiac protection in Klf15-KO/T2D mice. These results demonstrate partial KLF15-dependence for SDF-1ß's cardiac fibrotic protection from T2D, but not on SDF-1ß's protective effects on T2D-induced cardiac dysfunction. Further study showed that SDF-1ß inhibited palmitate-induced cardiomyocyte fibrosis through its receptor CXCR7-mediated activation of p38ß MAPK signaling pathway.


Assuntos
Quimiocina CXCL12/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Fatores de Transcrição Kruppel-Like/deficiência , Animais , Linhagem Celular , Quimiocina CXCL12/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ratos
18.
Med Sci Monit ; 27: e932545, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34400603

RESUMO

BACKGROUND The type of traumatic temporomandibular joint (TMJ) ankylosis depends on the degree of severity of TMJ trauma. Here, we performed comprehensive differential molecular profiling between TMJ fibrous and bony ankylosis. MATERIAL AND METHODS Six sheep were used and a bilateral different degree of TMJ trauma was performed to induce fibrous ankylosis in one side and bony ankylosis in the other side. The ankylosed calluses were harvested at days 14 and 28 postoperatively and analyzed by Affymetrix OviGene-1_0-ST microarrays. DAVID was used to perform the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis for the different expression genes (DEGs). The DEGs were also typed into protein-protein interaction (PPI) networks to get the interaction data. Ten DEGs, including 7 hub genes from PPI analysis, were confirmed by real-time PCR. RESULTS We found 90 and 323 DEGs at least 2-fold at days 14 and 28, respectively. At day 14, bony ankylosis showed upregulated DEGs, such as TLR8, SYK, NFKBIA, PTPRC, CD86, ITGAM, and ITGAL, indicating a stronger immune and inflammatory response and cell adhesion, while genes associated with anti-adhesion (PRG4) and inhibition of osteoblast differentiation (SFRP1) had higher expression in fibrous ankylosis. At day 28, bony ankylosis showed increased biological process related to new bone formation, while fibrous ankylosis was characterized by a prolonged immune and inflammatory reaction. CONCLUSIONS This study provides a differential gene expression profile between TMJ fibrous and bony ankylosis. Further study of these key genes may provide new ideas for future treatment of TMJ bony ankylosis.


Assuntos
Anquilose/genética , Fibrose/genética , Transtornos da Articulação Temporomandibular/genética , Traumatismos do Nervo Trigêmeo/genética , Animais , Anquilose/patologia , Modelos Animais de Doenças , Expressão Gênica/genética , Fraturas Mandibulares/genética , Análise em Microsséries , Ovinos/genética , Articulação Temporomandibular/metabolismo , Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/patologia , Transcriptoma , Traumatismos do Nervo Trigêmeo/patologia
19.
Ecotoxicol Environ Saf ; 221: 112456, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198187

RESUMO

Biochar-derived water-extractable organic matter (WEOM) was obtained under low-temperature pyrolysis (300 °C) using corncob as raw material. WEOM may affect the mobility and bioavailability of soil heavy metals (HMs) through complexation when biochar was used for soil HM remediation. Herein, the characteristics of complexation between HMs (Cr(III) and Cu(II)) and biochar-derived WEOM were investigated by using spectroscopic techniques in conjunction with parallel factor (PARAFAC) analysis and two-dimensional correlation spectroscopy (2D-COS). Six components were identified by PARAFAC modeling, in which protein-, fulvic- and humic-like components accounted for 48.86%, 25.63% and 25.51%, respectively. A nonlinear model was employed to determine the conditional stability constant (KM) and total ligand concentration (CL) of WEOM-HM complexes. The log KM values were in the range of 4.02-5.04 for WEOM-Cr(III) and 4.04-6.58 for WEOM-Cu(II). The 2D-COS in conjunction with log-transformed synchronous fluorescence spectroscopy (SFS) suggested that WEOM components were preferentially complexed with HMs in the following order: 433/270, 433/335, 496/270, 496/335, 370/335, 433/402, 496/402, 335/290, 402/290 for Cr(III), and 290/280, 390/280, 433/280, 496/280, 433/335, 496/335, 390/335, 433/420, 496/402, 335/290, 316/290 for Cu(II). The results of 2D-FTIR-COS suggested a preferential bonding of Cr(III) to the C-N group of alkyl, and Cu(II) to the CO group of alcohols, ethers and esters. Meanwhile, the CO group of ethers and the CN group of alkyl indicated preferential susceptibilities for the addition of Cr(III) and Cu(II) at different concentrations. In addition, protein-like components had remarkably higher total ligand concentration (CL) than fulvic- or humic-like components.


Assuntos
Carvão Vegetal/química , Cromo/química , Cobre/química , Benzopiranos/química , Substâncias Húmicas , Proteínas/química , Pirólise , Temperatura , Água/química , Zea mays
20.
Ecotoxicol Environ Saf ; 214: 112064, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33691241

RESUMO

Hydrophyte decomposition caused large amounts of dissolved organic matter (DOM) to enter aquatic environment that influence the migration and transformation of heavy metals (HMs). Six hydrophytes with five dry weight gradients (DWG) were used for the decomposition experiments. The results showed that protein-like materials occupy relatively high content in the hydrophyte-derived DOM. The binding properties of DOM-Cu(II) have been explored by using two-dimensional correlation spectroscopy (2D-COS) in conjunction with synchronous fluorescence spectroscopy (SFS) and log-transformed SFS. The weak signals of binding site can be amplified by the log-transformed 2D-COS analysis. Herein, more binding sites can be identified by the log-transformed 2D-COS analysis. The results reveal that tryptophan-like materials show a preferential sequence of binding Cu(II) in the hydrophyte-derived DOM with a relatively low DWG and sediment DOM, and fulvic-like substances indicate a preferential sequence of binding Cu(II) in the hydrophyte-derived DOM with a relatively high DWG. Meanwhile, the results of binding parameters indicate that the log K is the range of 3.61-4.25, 4.33-4.74, 4.59-4.97, 3.91-4.41, and 4.14-4.78 for D1-D5, respectively, suggesting that hydrophyte decomposition can change the binding affinity between DOM components and Cu(II). The complexes of fluorescent components with Cu(II) showed a high log K value at long wavelength (e.g. humic-like substances), and a relatively low fluorescent ligand proportion (f%) at shorter wavelength in the hydrophyte-derived DOM. However, the log K is the range of 3.08-4.31, 4.09-4.45, 3.93-4.35, 4.39-4.75, and 3.95-4.36 for C1-C5, separately. Protein-like substances with Cu(II) showed a relatively high log K value with the exception of C4. The log-transformed 2D-COS can be an analytical tool to understand the binding heterogeneity of DOM with HMs. The study can provide a guide for managing and controlling the effects of hydrophyte decomposition.


Assuntos
Cobre/metabolismo , Poluentes Químicos da Água/metabolismo , Corantes , Cobre/química , Substâncias Húmicas/análise , Metais Pesados/química , Espectrometria de Fluorescência/métodos
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