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2.
Development ; 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34651188

RESUMO

Although understanding of human placental development is still limited, two models, trophoblast organoids and trophoblast stem cells (TSC) provide new useful tools to study this. Both differentiate from villous cytotrophoblast (VCT) to either extravillous trophoblast (EVT) or syncytiotrophoblast (SCT). Here, we compare transcriptomes and miRNA profiles of these models to identify which trophoblast they resemble in vivo. Our findings indicate that TSC do not readily undergo SCT differentiation and closely resemble cells at the base of the cell columns from where EVT are derived. In contrast, organoids are similar to VCT and undergo spontaneous SCT differentiation. A defining feature of human trophoblast is that VCT and SCT are HLA null whilst EVT express HLA-C, -G, -E molecules. We find that trophoblast organoids retain these in vivo characteristics. In contrast, TSC do express classical HLA-A and HLA-B molecules and still maintain their expression after EVT differentiation with upregulation of HLA-G. Furthermore, HLA expression in TSC differs when grown in 3D rather than 2D suggesting mechanical cues are important. Our results will allow choice of the most suitable model to study trophoblast development, function and pathology.

3.
Can Respir J ; 2021: 6947037, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621458

RESUMO

Objective: We design a prospective control study on the utilization of transbronchial cryobiopsy guided by EBUS-GS (EBUS-GS-TBCB) to diagnose PPLs. Methods: PPLs were defined as pulmonary nodules or masses with a diameter from 10 mm to 50 mm. PPLs were randomly divided into group EBUS-GS-TBCB and transbronchial biopsy by forceps guided under EBUS-GS (EBUS-GS-TBB). Results: 28 cases were involved in group EBUS-GS-TBCB and 31 cases were in group EBUS-GS-TBB. The mean sizes of PPLs were 30.23 ± 11.10 mm in group EBUS-GS-TBCB and 28.69 ± 8.62 mm in group EBUS-GS-TBB (t = 0.600, p=0.551). The diagnostic yields of EBUS-GS-TBCB and EBUS-GS-TBB were 75% and 64.52% respectively, and the difference between the two groups was not significant (χ 2 value = 0.137, p=0.711). If only the first specimen was taken into account, the diagnostic yields from EBUS-GS-TBCB and EBUS-GS-TBB were 64.29% (18/28 cases) and 35.48% (11/31 cases), respectively. The difference was statistically significant by Fisher's Exact Test (χ 2 value = 4.883, p=0.038). The total incidence rates of bleeding were 21.43% and 6.45%, respectively, in groups EBUS-GS-TBCB and EBUS-GS-TBB. The total incidence rates of pneumothorax were 7.14% and 0, respectively, in groups EBUS-GS-TBCB and EBUS-GS-TBB. Conclusion: The diagnostic yield of EBUS-GS-TBCB was slightly higher than that of EBUS-GS-TBB for the diagnosis of PPLs. EBUS-GS-TBCB might be useful if only the first sample was taken into account.

4.
J Mater Chem B ; 9(36): 7435-7446, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551058

RESUMO

Cancer vaccines based on DNA encoding oncogenes have shown great potential in preclinical studies. However, the efficacy of DNA vaccines is limited by their weak immunogenicity because of low cellular internalisation and insufficient activation of dendritic cells (DCs). Calcium phosphate (CP) nanoparticles (NPs) are biodegradable vehicles with low toxicity and high loading capacity of DNA but suffer from stability issues. Here we employed adenosine triphosphate (ATP) as a dual functional agent, i.e. stabiliser for CP and immunological adjuvant, and applied the ATP-modified CP (ACP) NPs to the DNA vaccine. ACP NP-enhanced cellular uptake and improved transfection efficiency of DNA vaccine, and further showed the ability to activate DCs that are critical for them to prime T cells in cancer immunotherapy. As a result, a higher level of antigen-specific antibody with stronger tumour growth inhibition was achieved in mice immunised with the ACP-DNA vaccine. Overall, this one-step synthesised ACP NPs are an efficient nano-delivery system and nano-adjuvant for cancer DNA vaccines.

5.
Viruses ; 13(8)2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34452313

RESUMO

The tomato Sw-5b gene confers resistance to tomato spotted wilt virus (TSWV) and encodes a nucleotide-binding leucine-rich repeat (NLR) protein with an N-terminal Solanaceae-specific domain (SD). Although our understanding of how Sw-5b recognizes the viral NSm elicitor has increased significantly, the process by which Sw-5b activates downstream defense signaling remains to be elucidated. In this study, we used a tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) system to investigate the roles of the SGT1/RAR1, EDS1/NDR1, NPR1, and NRC/ADR1/NRG1 genes in the Sw-5b-mediated signaling pathway. We found that chaperone SGT1 was required for Sw-5b function, but co-chaperone RAR1 was not. Sw-5b-mediated immune signaling was independent of both EDS1 and NDR1. Silencing NPR1, which is a central component in SA signaling, did not result in TSWV systemic infection in Sw-5b-transgenic N. benthamiana plants. Helper NLR NRCs (NLRs required for cell death) were required for Sw-5b-mediated systemic resistance to TSWV infection. Suppression of NRC2/3/4 compromised the Sw-5b resistance. However, the helper NLRs ADR1 and NRG1 may not participate in the Sw-5b signaling pathway. Silencing ADR1, NRG1, or both genes did not affect Sw-5b-mediated resistance to TSWV. Our findings provide new insight into the requirement for conserved key components in Sw-5b-mediated signaling pathways.

6.
J Sci Food Agric ; 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34355399

RESUMO

BACKGROUND: Improving potato productivity and quality plays an important role in enhancing global food security and human health. However, inappropriate fertilizer management negatively affects potato growth and tuber development, especially in developing countries where there are large numbers of smallholders without modern soil testing equipment. Nutrient Expert (NE), a new and convenient fertilization decision system, was evaluated in the present study by conducting four site-years field experiments in Northeast China, aiming to determine its effectiveness and applicability for potato production relative to local farmers' practice (FP) and fertilizer recommendation based on soil testing (ST). RESULTS: The excessive fertilization at planting promoted seedling growth for potato plants in FP. Nevertheless, superior plant growth and tuber development were observed in NE at the middle and later growing stages, by optimizing fertilizer input and implementing split fertilization. Overall, compared to FP, the NE system increased total and marketable tuber yields by 12-15% and 16-26%, respectively, at the same time as obtaining 19-31% higher net returns and enhanced fertilizer use efficiencies. Moreover, NE improved tuber quality by increasing the contents of starch, soluble protein and vitamin C and decreasing reducing sugar content relative to FP, as well as increasing starch yields by 23-52%. The ST method also showed comprehensive improvements in potato performances compared to FP, although it did not show any advantages compared to NE system. CONCLUSION: The NE system improved potato productivity and tuber quality by optimizing fertilization management, which is an effective and promising alternative to the ST method for potato production in China and other developing countries. © 2021 Society of Chemical Industry.

7.
Curr Biol ; 31(17): 3755-3767.e4, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34270946

RESUMO

The classical soybean (Glycine max) trait long juvenile (LJ) is essentially a reduction in sensitivity to short-day (SD) conditions for induction and completion of flowering, and has been introduced into soybean cultivars to improve yield in tropical environments. However, only one locus, J, is known to confer LJ in low-latitude varieties. Here, we defined two quantitative trait loci contributing to the LJ trait, LJ16.1 and LJ16.2, and identified them as the florigen (FT) homologs FT2a and FT5a, respectively. The two selected florigen variations both delay flowering time under SD conditions by repressing the floral meristem identity gene GmAPETALA1. Single mutants have a relatively subtle effect on flowering time and displayed a substantial genetic compensation response, but this was absent in ft2a ft5a double mutants, which showed an enhanced LJ phenotype that translated to higher yields under SD conditions. A survey of sequence diversity suggests that FT2a and FT5a variants have diverse origins and have played distinct roles as soybean spread to lower latitudes. Our results show that integration of variants in the florigen genes offers a strategy for customizing flowering time to adjust adaptation and improve crop productivity in tropical regions.

8.
Front Immunol ; 12: 607669, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234770

RESUMO

Innate lymphoid cells (ILCs) are the most abundant immune cells in the uterine mucosa both before and during pregnancy. Circumstantial evidence suggests they play important roles in regulating placental development but exactly how they contribute to the successful outcome of pregnancy is still unclear. Uterine ILCs (uILCs) include subsets of tissue-resident natural killer (NK) cells and ILCs, and until recently the phenotype and functions of uILCs were poorly defined. Determining the specific roles of each subset is intrinsically challenging because of the rapidly changing nature of the tissue both during the menstrual cycle and pregnancy. Single-cell RNA sequencing (scRNAseq) and high dimensional flow and mass cytometry approaches have recently been used to analyse uILC populations in the uterus in both humans and mice. This detailed characterisation has significantly changed our understanding of the heterogeneity within the uILC compartment. It will also enable key clinical questions to be addressed including whether specific uILC subsets are altered in infertility, miscarriage and pregnancy disorders such as foetal growth restriction and pre-eclampsia. Here, we summarise recent advances in our understanding of the phenotypic and functional diversity of uILCs in non-pregnant endometrium and first trimester decidua, and review how these cells may contribute to successful placental development.


Assuntos
Imunidade Inata , Células Matadoras Naturais/imunologia , Linfócitos/imunologia , Resultado da Gravidez , Útero/citologia , Útero/imunologia , Animais , Contagem de Células , Citocinas/imunologia , Endométrio/citologia , Endométrio/imunologia , Feminino , Humanos , Células Matadoras Naturais/classificação , Células Matadoras Naturais/fisiologia , Camundongos , Fenótipo , Gravidez
9.
Nat Commun ; 12(1): 3714, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140513

RESUMO

The mechanism behind transgenerational epigenetic inheritance is unclear, particularly through the maternal grandparental line. We previously showed that disruption of folate metabolism in mice by the Mtrr hypomorphic mutation results in transgenerational epigenetic inheritance of congenital malformations. Either maternal grandparent can initiate this phenomenon, which persists for at least four wildtype generations. Here, we use genome-wide approaches to reveal genetic stability in the Mtrr model and genome-wide differential DNA methylation in the germline of Mtrr mutant maternal grandfathers. We observe that, while epigenetic reprogramming occurs, wildtype grandprogeny and great grandprogeny exhibit transcriptional changes that correlate with germline methylation defects. One region encompasses the Hira gene, which is misexpressed in embryos for at least three wildtype generations in a manner that distinguishes Hira transcript expression as a biomarker of maternal phenotypic inheritance.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Metilação de DNA , Ferredoxina-NADP Redutase/genética , Ácido Fólico/metabolismo , Células Germinativas/metabolismo , Chaperonas de Histonas/metabolismo , Padrões de Herança/genética , Herança Materna/genética , Fatores de Transcrição/metabolismo , Animais , Biomarcadores/metabolismo , Proteínas de Ciclo Celular/genética , Embrião de Mamíferos/metabolismo , Epigênese Genética , Epigenômica , Feminino , Ferredoxina-NADP Redutase/metabolismo , Hereditariedade , Chaperonas de Histonas/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Espermatozoides/metabolismo , Fatores de Transcrição/genética , Trofoblastos/metabolismo , Sequenciamento Completo do Genoma
10.
Commun Biol ; 4(1): 701, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103657

RESUMO

Alterations in maternal physiological adaptation during pregnancy lead to complications, including abnormal birthweight and gestational diabetes. Maternal adaptations are driven by placental hormones, although the full identity of these is lacking. This study unbiasedly characterized the secretory output of mouse placental endocrine cells and examined whether these data could identify placental hormones important for determining pregnancy outcome in humans. Secretome and cell peptidome analyses were performed on cultured primary trophoblast and fluorescence-activated sorted endocrine trophoblasts from mice and a placental secretome map was generated. Proteins secreted from the placenta were detectable in the circulation of mice and showed a higher relative abundance in pregnancy. Bioinformatic analyses showed that placental secretome proteins are involved in metabolic, immune and growth modulation, are largely expressed by human placenta and several are dysregulated in pregnancy complications. Moreover, proof-of-concept studies found that secreted placental proteins (sFLT1/MIF and ANGPT2/MIF ratios) were increased in women prior to diagnosis of gestational diabetes. Thus, placental secretome analysis could lead to the identification of new placental biomarkers of pregnancy complications.


Assuntos
Placenta/metabolismo , Complicações na Gravidez/metabolismo , Proteoma/metabolismo , Animais , Células Cultivadas , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Placenta/citologia , Gravidez , Complicações na Gravidez/genética , Proteoma/análise , Proteoma/genética , Proteômica , Trofoblastos/citologia , Trofoblastos/metabolismo
11.
Commun Biol ; 4(1): 651, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140633

RESUMO

Assessment of the endometrium often necessitates a biopsy, which currently involves an invasive, transcervical procedure. Here, we present an alternative technique based on deriving organoids from menstrual flow. We demonstrate that organoids can be derived from gland fragments recovered from menstrual flow. To confirm they faithfully reflect the in vivo state we compared organoids derived from paired scratch biopsies and ensuing menstrual flow from patients undergoing in vitro fertilisation (IVF). We demonstrate that the two sets of organoids share the same transcriptome signature, derivation efficiency and proliferation rate. Furthermore, they respond similarly to sex steroids and early-pregnancy hormones, with changes in morphology, receptor expression, and production of 'uterine milk' proteins that mimic those during the late-secretory phase and early pregnancy. This technique has wide-ranging impact for non-invasive investigation and personalised approaches to treatment of common gynaecological conditions, such as endometriosis, and reproductive disorders, including failed implantation after IVF and recurrent miscarriage.


Assuntos
Endométrio/citologia , Menstruação , Organoides/citologia , Adulto , Células Cultivadas , Endométrio/crescimento & desenvolvimento , Endométrio/metabolismo , Feminino , Fertilização In Vitro , Humanos , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Projetos Piloto
12.
J Neural Eng ; 18(4)2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34157696

RESUMO

Objective.Interictal epileptiform discharges (IEDs) are an important and widely accepted biomarker used in the diagnosis of epilepsy based on scalp electroencephalography (EEG). Because the visual detection of IEDs has various limitations, including high time consumption and high subjectivity, a faster, more robust, and automated IED detector is strongly in demand.Approach.Based on deep learning, we proposed an end-to-end framework with multi-scale morphologic features in the time domain and correlation in sensor space to recognize IEDs from raw scalp EEG.Main Results.Based on a balanced dataset of 30 patients with epilepsy, the results of the five-fold (leave-6-patients-out) cross-validation shows that our model achieved state-of-the-art detection performance (accuracy: 0.951, precision: 0.973, sensitivity: 0.938, specificity: 0.968, F1 score: 0.954, AUC: 0.973). Furthermore, our model maintained excellent IED detection rates in an independent test on three datasets.Significance.The proposed model could be used to assist neurologists in clinical EEG interpretation of patients with epilepsy. Additionally, this approach combines multi-level output and correlation among EEG sensors and provides new ideas for epileptic biomarker detection in scalp EEG.


Assuntos
Aprendizado Profundo , Epilepsia , Eletroencefalografia , Epilepsia/diagnóstico , Humanos , Couro Cabeludo
13.
CNS Spectr ; 26(2): 174-175, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-34127087

RESUMO

STUDY OBJECTIVES: To describe characteristics of veterans with MDD and the different treatment regimens received during the first observed and treated major depressive episode (MDE). METHODS: A retrospective study was performed using the Veterans Health Administration (VHA) database from 4/1/2015 to 2/28/2019 (study period), supplemented with Medicare Part A/B/D data from 4/1/2015 to 12/31/2017. Adult veterans with ≥1 MDD diagnosis in the VHA database between 10/1/2015 and 2/28/2017 (index date) were included if they received ≥1 line of therapy (LOT) within a complete MDE. An MDE was considered as starting on the date of the first observed MDD diagnosis preceded by ≥6 months depression-free period (i.e. a period without an MDD diagnosis or antidepressant (AD) use); an MDE was considered as ended on the date of the last MDD diagnosis or the end of the medication supply of the last AD/augmentation medication, whichever came last and then followed by ≥6 months depression-free period. An MDE was required to begin and end during the study period. A LOT was defined as ≥1 AD at adequate dose and duration (≥6 weeks of continuous therapy with no gaps longer than 14 days) with or without an augmenting medication. Patients were required to have VA benefit enrollment for ≥6 months before (baseline) and ≥24 months after index (follow-up). Patient baseline demographic and clinical characteristics as well as the number and type of LOTs (up to the first six LOTs) received during the first observed and treated MDE were evaluated. RESULTS: Overall, 40,240 veterans with MDD were identified (mean ± standard deviation [SD] age: 50.9±16.3 years).The majority were male (83.9%), White (63.4%), and non-Hispanic (88.6%); 60.1% were unemployed or retired at some point during the study period. The most commonly observed baseline comorbidities included hypertension (27.5%), hyperlipidemia (20.8%), post-traumatic stress disorder (17.5%), and diabetes (14.8%). During the first observed and treated MDE (mean ± SD duration: 14.7 ± 8.6 months), patients received a mean of 1.6±1.0 LOTs, with 36.5% and 14.6% of patients receiving ≥2 and ≥3 LOTs, respectively; 0.8% of patients received ≥6 LOTs. The most commonly observed therapies were SSRI monotherapy (58.9%) followed by SNRI monotherapy (8.8%) in LOT1; SSRI monotherapy followed by AD augmented with anticonvulsants in LOT2 (SSRI monotherapy: 48.7%; AD augmentation with anticonvulsants:12.1%) and LOT3 (SSRI monotherapy: 43.5%; AD augmentation with anticonvulsants:15.0%). CONCLUSIONS: This study used an episodic approach to evaluate the current standard of care among veterans with MDD. During the first observed and treated MDE, about one in seven veterans received ≥3 LOTs, suggesting presence of treatment-resistant MDD. Monotherapy with SSRIs or SNRIs and combination therapies of AD with anticonvulsants were the most common therapies in the first three LOTs. FUNDING: Janssen Scientific Affairs, LLC.

14.
Food Chem ; 364: 130412, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34174646

RESUMO

Nitraria tangutorum Bobr. (NTB), mainly distributed in the Qaidam Basin of Tibetan Plateau, have high economic, ecological and medicinal value. The chemical compositions in the NTB fruits were tentatively analyzed and characterized by applying UPLC-Q-TOF-MS/MS. Total 45 constituents, including 9 hydroxycinnamic acids derivatives, 12 flavonols, 4 flavonoids, 1 trolox derivative, 8 ß-carboline alkaloids, 4 tryptophan derivatives, and 7 other amino acid derivatives were identified by comparing with standard products, and analyzing their retention times, characteristic fragment ions and deprotonated molecule ions. The activity studies in vitro indicated that NTB-Z and NTB-C extracts had marked inhibitory effects against sucrase and maltase. Further sucrose/maltose/starch tolerance experiment demonstrated that both NTB-Z and NTB-C extracts at 400 mg/kg could markedly lower the postprandial blood glucose (PBG) level in diabetic animals. All these results indicated that the NTB fruits could be used as the functional health food or medicine for controlling postprandial blood glucose level.


Assuntos
Alcaloides , Frutas , Animais , Cromatografia Líquida de Alta Pressão , Glucosidases , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem
15.
J Allergy Clin Immunol Pract ; 9(10): 3662-3671.e1, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34148858

RESUMO

BACKGROUND: U.S. guidelines recommend that patients with severe asthma be referred to specialists (allergists/immunologists or pulmonologists) for systematic assessment or comanagement; however, contemporary, real-world data on the frequency and impact of specialist care among U.S. severe asthma patients are lacking. OBJECTIVES: To quantify the frequency of asthma specialist visits among U.S. patients with severe asthma, identify patient demographic and clinical characteristics associated with specialist visits and describe health outcomes following specialist care. METHODS: Severe asthma patients aged 6 years or older were identified between January 1, 2015, and December 31, 2017, in the IQVIA PharMetrics® Plus database of commercially insured individuals, based on Healthcare Effectiveness Data and Information Set (HEDIS) criteria and Global Initiative for Asthma (GINA) step 4 or 5 treatment regimens. The frequency of asthma specialist (allergist/immunologist or pulmonologist) visits was described over 2 years. Patient characteristics associated with having 1 or more specialist visits were analyzed using multivariate regressions. Asthma exacerbations and health care resource utilization before and after specialist visit were compared. RESULTS: Of 54,332 patients identified, 38.2% had 1 or more specialist visits over 2 years. Patient characteristics predictive of specialist visits were asthma exacerbation frequency, younger age, and allergy/respiratory comorbidity burden (all P < .001). Among patients with 1 or more specialist visits, a lower prevalence of asthma exacerbations and rescue inhaler use was observed following the first observed specialist visit. CONCLUSIONS: Specialist care was observed in fewer than half of U.S. patients with severe asthma and was least frequent among older adult patients and those with more nonrespiratory comorbidities. Increased specialist involvement in managing severe asthma may help improve care and patient outcomes.

16.
J Exp Bot ; 72(18): 6581-6595, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34115862

RESUMO

Plant and animal intracellular nucleotide-binding and leucine-rich repeat (NLR) receptors play important roles in sensing pathogens and activating defense signaling. However, the molecular mechanisms underlying the activation of host defense signaling by NLR proteins remain largely unknown. Many studies have determined that the coil-coil (CC) or Toll and interleukin-1 receptor/resistance protein (TIR) domain of NLR proteins and their dimerization/oligomerization are critical for activating downstream defense signaling. In this study, we demonstrated that, in tomato, the nucleotide-binding (NB) domain Sw-5b NLR alone can activate downstream defense signaling, leading to elicitor-independent cell death. Sw-5b NB domains can self-associate, and this self-association is crucial for activating cell death signaling. The self-association was strongly compromised after the introduction of a K568R mutation into the P-loop of the NB domain. Consequently, the NBK568R mutant induced cell death very weakly. The NBCΔ20 mutant lacking the C-terminal 20 amino acids can self-associate but cannot activate cell death signaling. The NBCΔ20 mutant also interfered with wild-type NB domain self-association, leading to compromised cell death induction. By contrast, the NBK568R mutant did not interfere with wild-type NB domain self-association and its ability to induce cell death. Structural modeling of Sw-5b suggests that NB domains associate with one another and likely participate in oligomerization. As Sw-5b-triggered cell death is dependent on helper NLR proteins, we propose that the Sw-5b NB domain acts as a nucleation point for the assembly of an oligomeric resistosome, probably by recruiting downstream helper partners, to trigger defense signaling.

17.
Cancer Sci ; 112(7): 2679-2691, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33949040

RESUMO

BCR-ABL1 gene fusion associated with additional DNA lesions involves the pathogenesis of chronic myelogenous leukemia (CML) from a chronic phase (CP) to a blast crisis of B lymphoid (CML-LBC) lineage and BCR-ABL1+ acute lymphoblastic leukemia (BCR-ABL1+ ALL). The recombination-activating gene RAG1 and RAG2 (collectively, RAG) proteins that assemble a diverse set of antigen receptor genes during lymphocyte development are abnormally expressed in CML-LBC and BCR-ABL1+ ALL. However, the direct involvement of dysregulated RAG in disease progression remains unclear. Here, we generate human wild-type (WT) RAG and catalytically inactive RAG-expressing BCR-ABL1+ and BCR-ABL1- cell lines, respectively, and demonstrate that BCR-ABL1 specifically collaborates with RAG recombinase to promote cell survival in vitro and in xenograft mice models. WT RAG-expressing BCR-ABL1+ cell lines and primary CD34+ bone marrow cells from CML-LBC samples maintain more double-strand breaks (DSB) compared to catalytically inactive RAG-expressing BCR-ABL1+ cell lines and RAG-deficient CML-CP samples, which are measured by γ-H2AX. WT RAG-expressing BCR-ABL1+ cells are biased to repair RAG-mediated DSB by the alternative non-homologous end joining pathway (a-NHEJ), which could contribute genomic instability through increasing the expression of a-NHEJ-related MRE11 and RAD50 proteins. As a result, RAG-expressing BCR-ABL1+ cells decrease sensitivity to tyrosine kinase inhibitors (TKI) by activating BCR-ABL1 signaling but independent of the levels of BCR-ABL1 expression and mutations in the BCR-ABL1 tyrosine kinase domain. These findings identify a surprising and novel role of RAG in the functional specialization of disease progression in BCR-ABL1+ leukemia through its endonuclease activity.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Homeodomínio/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas Nucleares/metabolismo , Hidrolases Anidrido Ácido/metabolismo , Animais , Crise Blástica/genética , Crise Blástica/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Quebras de DNA de Cadeia Dupla , Reparo do DNA por Junção de Extremidades , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Progressão da Doença , Proteínas de Fusão bcr-abl/genética , Instabilidade Genômica , Xenoenxertos , Histonas/análise , Proteínas de Homeodomínio/genética , Humanos , Técnicas In Vitro , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteína Homóloga a MRE11/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico
18.
Nat Plants ; 7(4): 452-467, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33846593

RESUMO

Meiotic crossovers are tightly restricted in most eukaryotes, despite an excess of initiating DNA double-strand breaks. The majority of plant crossovers are dependent on class I interfering repair, with a minority formed via the class II pathway. Class II repair is limited by anti-recombination pathways; however, similar pathways repressing class I crossovers have not been identified. Here, we performed a forward genetic screen in Arabidopsis using fluorescent crossover reporters to identify mutants with increased or decreased recombination frequency. We identified HIGH CROSSOVER RATE1 (HCR1) as repressing crossovers and encoding PROTEIN PHOSPHATASE X1. Genome-wide analysis showed that hcr1 crossovers are increased in the distal chromosome arms. MLH1 foci significantly increase in hcr1 and crossover interference decreases, demonstrating an effect on class I repair. Consistently, yeast two-hybrid and in planta assays show interaction between HCR1 and class I proteins, including HEI10, PTD, MSH5 and MLH1. We propose that HCR1 plays a major role in opposition to pro-recombination kinases to restrict crossovers in Arabidopsis.


Assuntos
Arabidopsis/genética , Sequência de Aminoácidos , Arabidopsis/metabolismo , Troca Genética , Meiose , Alinhamento de Sequência
19.
ACS Appl Mater Interfaces ; 13(12): 14015-14027, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33751882

RESUMO

Cancer vaccines have attracted increasing attention for their application in tumor immunotherapy. DNA vaccines are one of them that have been proven very promising with the advantages of safety, rapid design, and low cost. However, the low stability, ineffective cell internalization, and low immunostimulation hinder their wide application. Thus, developing targeted and safe systems to effectively deliver DNA vaccines becomes a vital step. In this study, we report the development of mannose- and bisphosphonate (BP)-modified calcium phosphate (CP) nanoparticles (NPs) as efficient vaccine delivery vehicles by targeting C-type lectin receptors (CLRs) on antigen-presenting cells (APCs). Using a model antigen ovalbumin (OVA)-encoded plasmid DNA (pOVA) as a model vaccine, we demonstrate that mannose-modified and BP-stabilized CP (MBCP) nanoparticles are mono-dispersed for enhanced uptake by APCs and subsequently induce OVA antigen presentation and immunostimulation. Mice immunized with MBCP-pOVA nanovaccines show a significantly stronger anti-OVA antibody response with a quicker IgG1 and IgG2a antibody production than unmodified NPs. Moreover, MBCP-pOVA immunization significantly inhibits the growth of OVA-expressing E.G7 tumor cells in C57BL/6J mice. Our data collectively suggest that the modifications to enhance the stability and targeting ability of MBCP NPs are essential for effective delivery of DNA vaccines and promote robust anti-tumor immunity.


Assuntos
Vacinas Anticâncer/administração & dosagem , Portadores de Fármacos/química , Manose/química , Nanopartículas/química , Neoplasias/terapia , Vacinas de DNA/administração & dosagem , Animais , Fosfatos de Cálcio/química , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Difosfonatos/química , Humanos , Imunoterapia , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Vacinas de DNA/uso terapêutico
20.
Nano Lett ; 21(5): 1992-2000, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33616397

RESUMO

One major frustration in developing antibiotics is that bacteria can quickly develop resistance that would require an entirely new cycle of research and clinical testing to overcome. Although plenty of bactericidal nanomaterials have been developed against increasingly severe superbugs, few reports have studied the resistance to these nanomaterials. Herein, we show that antibacterial 4,6-diamino-2-pyrimidine thiol (DAPT)-capped gold nanoparticles (AuDAPTs) can induce a 16-fold increased minimum inhibitory concentration (MIC) of E. coli only after very long term exposure (183 days), without developing cross-resistance to commercialized antibiotics. Strikingly, we recovered the bactericidal activities of AuDAPTs to the resistant strain by tuning the sizes of AuDAPTs without employing new chemicals. Such slow, easy-to-handle resistance induced by AuDAPTs is unprecedented compared to traditional antibiotics or other nanomaterials. In addition to the novel antibacterial activities and biocompatibilities, our approach will accelerate the development of gold nanomaterial-based therapeutics against multi-drug-resistant (MDR) bacterial infections.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Escherichia coli , Ouro , Humanos , Testes de Sensibilidade Microbiana
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