Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
iScience ; 27(3): 109256, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455976

RESUMO

To address the challenge of solid tumor targeting in CAR-T therapy, we utilized the A56 antigen, which is uniquely expressed on a diverse range of cancer cells following the systemic administration of an oncolytic vaccinia virus (OVV). Immunohistochemical assays precisely confirmed exclusive localization of A56 to tumor tissues. In vitro studies demonstrated a distinct superiority of A56-dependent CAR-T cytotoxicity across multiple cancer cell lines. Building on these in vitro observations, we strategically administered A56 CAR-T cells, OVV, and hydroxyurea (HU) combination in HCT-116 tumor-bearing non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, leading to a significant reduction in tumor size and an extended time to progression. Consequently, A56-targeting combinatorial immunotherapy provides the benefit of reducing inadvertent CAR-T effects on normal cells while preserving its effectiveness against cancer cells. Furthermore, our approach of implanting A56 via OVV on tumors facilitates a wide therapeutic application of CAR-T cells across various solid tumors.

2.
Res Sq ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38464120

RESUMO

This prospective study evaluated the relationship between laser speckle contrast imaging (LSCI) ocular blood flow velocity (BFV) and five birth parameters: gestational age (GA), postmenstrual age (PMA), and chronological age (CA) at the time of measurement, birth weight (BW), and current weight (CW) in preterm neonates at risk for retinopathy of prematurity (ROP).38 Neonates with BW < 2 kg, GA < 32 weeks, and PMA between 27-47 weeks underwent 91 LSCI sessions. Correlation tests and regression analysis were performed to quantify relationships between birth parameters and ocular BFV. Mean ocular BFV index in this cohort was 8.8 +/- 4.0 IU. BFV positively correlated with PMA (r = 0.3, p = 0.01), CA (r = 0.3, p = 0.005), and CW (r = 0.3, p = 0.02). BFV did not correlate with GA nor BW (r=-0.2 and r=-0.05, p > 0.05). Regression analysis with mixed models demonstrated that BFV increased by 1.2 for every kilogram of CW, by 0.34 for every week of CA, and by 0.36 for every week of PMA (p = 0.03, 0.004, 0.007, respectively). Our findings indicate that increased age and weight are associated with increased ocular BFV measured using LSCI in premature infants. Future studies investigating the associations between ocular BFV and ROP clinical severity must control for age and/or weight of the infant.

4.
Biotechniques ; 76(3): 114-118, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38131320

RESUMO

A colorimetric loop-mediated isothermal amplification assay detects changes in pH during amplification based on color changes at a constant temperature. Currently, various studies have focused on developing and assessing molecular point-of-care testing instruments. In this study, we evaluated amplified DNA concentrations measured using the colorimetric LAMP assay of the 1POT™ Professional device (1drop Inc, Korea). Results of the 1POT analysis of clinical samples were compared with measurements obtained from the Qubit™ 4 and NanoDrop™ 2000 devices (both from Thermo Fisher Scientific, MA, USA). These results showed a correlation of 0.98 (95% CI: 0.96-0.99) and 0.96 (95% CI: 0.92-0.98) between 1POT and the Qubit and NanoDrop. 1POT can measure amplified DNA accurately and is suitable for on-site molecular diagnostics.


Assuntos
Colorimetria , DNA , DNA/genética , DNA/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade
5.
Cancers (Basel) ; 15(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37190310

RESUMO

Peritoneal metastasis, also known as peritoneal carcinomatosis (PC), is a refractory cancer that is typically resistant to conventional therapies. The typical treatment for PC is a combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Recently, research in this area has seen significant advances, particularly in immunotherapy as an alternative therapy for PC, which is very encouraging. Catumaxomab is a trifunctional antibody intraperitoneal (IP) immunotherapy authorized in Europe that can be used to diminish malignant ascites by targeting EpCAM. Intraperitoneal (IP) immunotherapy breaks immunological tolerance to treat peritoneal illness. Increasing T-cell responses and vaccination against tumor-associated antigens are two methods of treatment. CAR-T cells, vaccine-based therapeutics, dendritic cells (DCs) in combination with pro-inflammatory cytokines and NKs, adoptive cell transfer, and immune checkpoint inhibitors are promising treatments for PC. Carcinoembryonic antigen-expressing tumors are suppressed by IP administration of CAR-T cells. This reaction was strengthened by anti-PD-L1 or anti-Gr1. When paired with CD137 co-stimulatory signaling, CAR-T cells for folate receptor cancers made it easier for T-cell tumors to find their way to and stay alive in the body.

6.
Biomedicines ; 8(10)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081279

RESUMO

Viral replication of thymidine kinase deleted (tk-) vaccinia virus (VV) is attenuated in resting normal cells, enabling cancer selectivity, however, replication potency of VV-tk- appears to be diminished in cancer cells. Previously, we found that wild-type herpes simplex virus (HSV)-tk (HSV-tk) disappeared in most of the recombinant VV after multiple screenings, and only a few recombinant VV containing naturally mutated HSV-tk remained stable. In this study, VV-tk of western reserve (WR) VV was replaced by A167Y mutated HSV-tk (HSV-tk418m), to alter nucleoside selectivity from broad spectrum to purine exclusive selectivity. WOTS-418 remained stable after numerous passages. WOTS-418 replication was significantly attenuated in normal cells, but cytotoxicity was almost similar to that of wild type WR VV in cancer cells. WOTS-418 showed no lethality following a 5 × 108 PFU intranasal injection, contrasting WR VV, which showed 100% lethality at 1 × 105 PFU. Additionally, ganciclovir (GCV) but not BvdU inhibited WOTS-418 replication, confirming specificity to purine nucleoside analogs. The potency of WOTS-418 replication inhibition by GCV was > 10-fold higher than that of our previous truncated HSV-tk recombinant OTS-412. Overall, WOTS-418 demonstrated robust oncolytic efficacy and pharmacological safety which may delegate it as a candidate for future clinical use in OV therapy.

7.
Cancer Res Treat ; 52(1): 309-319, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31401821

RESUMO

PURPOSE: The purpose of this study was to assess characteristics of SJ-815, a novel oncolytic vaccinia virus lacking a functional thymidine kinase-encoding TK gene, and instead, having two human transgenes: the IFNB1 that encodes interferon ß1, and the CES2 that encodes carboxylesterase 2, which metabolizes the prodrug, irinotecan, into cytotoxic SN-38. MATERIALS AND METHODS: Viral replication and dissemination of SJ-815 were measured by plaque assay and comet assay, respectively, and compared to the backbone of SJ-815, a modified Western Reserve virus named WI. Tumor cytotoxicity of SJ-815 (or mSJ-815, which has the murine IFNB1 transgene for mouse cancers) was evaluated using human and mouse cancer cells. Antitumor effects of SJ-815, with/without irinotecan, were evaluated using a human pancreatic cancer-bearing mouse model and a syngeneic melanoma-bearing mouse model. The SN-38/ irinotecan ratios in mouse melanoma tissue 4 days post irinotecan treatment were compared between groups with and without SJ-815 intravenous injection. RESULTS: SJ-815 demonstrated significantly lower viral replication and dissemination, but considerably stronger in vitro tumor cytotoxicity than WI. The combination use of SJ-815 plus irinotecan generated substantial tumor regression in the human pancreatic cancer model, and significantly prolonged survival in the melanoma model (hazard ratio, 0.11; 95% confidence interval, 0.02 to 0.50; p=0.013). The tumor SN-38/irinotecan ratios were over 3-fold higher in the group with SJ-815 than those without (p < 0.001). CONCLUSION: SJ-815 demonstrates distinct characteristics gained from the inserted IFNB1 and CES2 transgenes. The potent antitumor effects of SJ-815, particularly when combined with irinotecan, against multiple solid tumors make SJ-815 an attractive candidate for further preclinical and clinical studies.


Assuntos
Carboxilesterase/genética , Expressão Gênica , Vetores Genéticos/genética , Interferon beta/genética , Vírus Oncolíticos/genética , Transgenes , Vírus Vaccinia/genética , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Engenharia Genética , Humanos , Masculino , Melanoma Experimental , Camundongos , Neoplasias/genética , Neoplasias/mortalidade , Neoplasias/patologia , Neoplasias/terapia , Terapia Viral Oncolítica , Taxa de Sobrevida , Resultado do Tratamento , Replicação Viral , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Korean J Women Health Nurs ; 25(2): 169-181, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37684854

RESUMO

PURPOSE: To determine association of contraceptive knowledge, sexual double standard, and contraceptive self-efficacy among unmarried women in their 30s and 40s. METHODS: With a survey design, data were collected from 119 unmarried women in their 30s and 40s in G city of Korea from September 2017 to March 2018. Data were analyzed by descriptive statistics, independent t-test, one-way ANOVA, Scheffé test, Pearson's correlation coefficients, and stepwise multiple regression. RESULTS: Contraceptive knowledge, sexual double standard, and contraceptive self-efficacy scores of participants were 8.97±2.22, 18.54±5.57, and 45.84 ± 6.90, respectively. Contraceptive self-efficacy was negatively correlated with sexual double standard. Factors influencing contraceptive self-efficacy were sexual double standard (ß =-.26, p=.003), existence of boyfriend (ß=.25, p=.004), and contraceptive education need for adults (ß=.17, p=.044). They explained 19% of contraceptive self-efficacy of participants. CONCLUSION: To increase contraceptive self-efficacy of unmarried women in their 30s and 40s, lowering sexual double standard and developing customized contraceptive education according to age and knowledge level are needed. Research on factors related to contraceptive self-efficacy of unmarried women in their 30s and 40s from various regions are also needed in the future.

9.
Drug Des Devel Ther ; 12: 2467-2474, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30122903

RESUMO

PURPOSE: Oncolytic poxvirus has shown promise in treating various solid tumors, such as liver cancer, and administration of oncolytic poxvirus via the hepatic artery may provide more survival benefits than other routes of administration. However, there is a lack of safety information to guide the application of hepatic arterial infusion (HAI) of oncolytic poxvirus in human studies. To investigate the acute and chronic toxicity of HAI administration of oncolytic poxvirus in animals and provide safety information for future human studies. METHODS: VVtk-, a vaccinia poxvirus with inactivated thymidine kinase gene, was administered via HAI to rabbits with normal liver function under angiography (1×108 or 1×109 pfu), and rats with N-nitrosomorpholine-induced precancerous liver cirrhosis under open surgery (1×108 pfu). Body weights and survival were monitored and blood samples were collected for hematological and biochemical tests. Distribution of A56 (a specific marker for poxvirus infection) in rabbit organs was evaluated using immunofluorescence assays. RESULTS: HAI of high doses of VVtk- did not cause any acute or chronic changes in body weight, survival or in biochemical, hematological tests in the 2 animal models, and none of the changes showed dose dependency (in rabbit study), or were influenced by liver cirrhosis (in rat study). A56 was not detected in any of the major rabbit organs. CONCLUSION: HAI may provide a safe alternative route of oncolytic poxvirus administration for human studies.


Assuntos
Neoplasias Hepáticas/terapia , Terapia Viral Oncolítica/efeitos adversos , Poxviridae , Animais , Feminino , Artéria Hepática , Infusões Intra-Arteriais , Cirrose Hepática Experimental/terapia , Coelhos , Ratos , Ratos Sprague-Dawley
10.
Korean J Women Health Nurs ; 24(1): 14-23, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37684909

RESUMO

PURPOSE: To determine the effect of sex communication with friends and sexual double standard on contraceptive self-efficacy among university students. METHODS: With a survey design, data were collected from 251 university students from three universities in G city from September 2016 to October 2016. Data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression. RESULTS: Sex communication with friends, sexual double standard, and contraceptive self-efficacy scores of participants were 58.82±8.78, 21.73±6.00, and 44.20±5.91, respectively. Sex communication with friends and sexual double standard were related to contraceptive self-efficacy. Sexual double standard, sex communication with friends, female, contraceptive education, and contraceptive experience explained 33% of contraceptive self-efficacy of participants. CONCLUSION: Sexual double standard and sex communication with friends were influencing factors of contraceptive self-efficacy. To improve contraceptive self-efficacy of university students, a program is needed to eliminate sexual double standard and improve sex communication with friends among university students in Korea.

11.
Korean J Women Health Nurs ; 22(3): 151-161, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37684864

RESUMO

PURPOSE: The purpose of this study was to develop and test the validity and reliability of the Korean version of the Contraceptive Self-efficacy (K-CSE) scale. METHODS: The K-CSE scale was developed through forward-backward translation methods. Construct and criterion validity and internal consistency reliability were calculated using SPSS/WIN 21.0. Data were collected from 257 women students from two universities in G city, South Korea. RESULTS: The factor structure of the K-CSE scale showed the cumulative variance as 62.9% in the factor analysis. Factor loading of 13 items on four subscales ranged from .47 to .88. Factors were named as 'initiative of contraceptive use', 'sexual assertiveness', 'refusal of sexual intercourse', and 'autonomic sexual behavior'. Criterion validity compared to the Sexual Autonomy Measurement (SAM) showed significant correlation. Cronbach's α for the reliability of each subscale were .50~.82 and .76 for the total scale. CONCLUSION: The findings of this study demonstrate that the K-CSE scale is a satisfactory valid and reliable scale. Therefore, the CSE scale can be useful in measuring contraceptive self-efficacy among women university students in Korea.

12.
Clin Hypertens ; 21: 24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26893934

RESUMO

BACKGROUND: Epicardial fat tissue is known to have an unique endocrine function which affect the cardiac autonomic system. Heart rate recovery (HRR) is a simple non-invasive measurement that assesses autonomic nervous system dysfunction. We aimed to investigate the association among epicardial fat thickness (EFT), HRR and circadian blood pressure (BP) variation in patients with hypertension. METHODS: A total of 358 consecutive patients who underwent both 24-hour ambulatory BP monitoring (ABPM) and a treadmill test were enrolled. Echocardiographic EFT and HRR, defined as peak heart rate minus heart rate after a 1-min recovery time, were measured. Patients were classified according to the ABPM; 147 patients with hypertension with a dipping pattern at night (dippers), 140 patients with hypertension with a non-dipping pattern at night (non-dippers) and 71 normotensive controls. RESULTS: EFT was significantly higher in hypertensive patients, especially in the non-dipper group, compared to the controls (non-dippers, 7.5 ± 2.9 mm; dippers, 6.6 ± 1.6 mm; controls, 5.5 ± 2.1 mm; p < 0.001). HRR was significantly lower in both hypertensive groups as compared to the control group and was the lowest in the non-dipper group (non-dipper, 26.6 ± 18.6; dipper, 29.5 ± 21.5; control, 71.4 ± 19.8; p < 0.001). EFT was significantly correlated with age, body mass index, 24-hour mean systolic BP and 24 h mean BP variability, whereas exercise duration, metabolic equivalents (METs) and HRR were inversely correlated with EFT. Furthermore, EFT > 6.7 mm was associated with a blunted HRR with 76 % sensitivity and 61 % specificity (ROC area under curve: 0.71, 95 % confidence interval, CI = 0.65-0.76, p < 0.001). In a multivariate analysis, EFT (odds ratio, OR = 3.53, 95 % CI = 1.20-10.37, p = 0.022) and 24-hour mean BP variability (OR = 1.09, 95 % CI = 1.03-1.16, p = 0.005) were independent predictors of a blunted HRR defined as HRR ≤ 12 beats (n = 63) in patients with hypertension. CONCLUSION: EFT and HRR were significantly correlated with circadian BP variability in patients with hypertension. EFT and circadian BP variability were independent predictors of blunted HRR, which suggests a link between epicardial fat and autonomic dysregulation in hypertension.

13.
Proc Natl Acad Sci U S A ; 109(13): 5098-103, 2012 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-22411811

RESUMO

In plants, plasmodesmata (PD) serve as channels for micromolecular and macromolecular cell-to-cell transport. Based on structure, PD in immature tissues are classified into two types, simple and branched (X- and Y-shaped) or twinned. The maximum size of molecules capable of PD transport defines PD aperture, known as the PD size exclusion limit. Here we report an Arabidopsis mutation, decreased size exclusion limit1 (dse1), that exhibits reduced cell-to-cell transport of the small (524 Da) fluorescent tracer 8-hydroxypyrene-1,3,6-trisulfonic acid at the midtorpedo stage of embryogenesis. Correspondingly, the fraction of X- and Y-shaped and twinned PD was reduced in dse1 embryos compared with WT embryos at this stage, suggesting that the frequency of PD is related to transport capability. dse1 is caused by a point mutation in At4g29860 (previously termed TANMEI) at the last donor splice site of its transcript, resulting in alternative splicing in both the first intron and the last intron. AtDSE1 is a conserved eukaryotic 386-aa WD-repeat protein critical for Arabidopsis morphogenesis and reproduction. Similar to its homologs in mouse, null mutants are embryo-lethal. The weak loss-of-function mutant dse1 exhibits pleiotropic phenotypes, including retarded vegetative growth, delayed flowering time, dysfunctional male and female organs, and delayed senescence. Finally, silencing of DSE1 in Nicotiana benthamiana leaves leads to reduced movement of GFP fused to tobacco mosaic virus movement protein. Thus, DSE1 is important for regulating PD transport between plant cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/embriologia , Plasmodesmos/metabolismo , Animais , Arabidopsis/metabolismo , Arabidopsis/ultraestrutura , Transporte Biológico , Clonagem Molecular , Espaço Extracelular/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Mutação/genética , Fenótipo , Plasmodesmos/ultraestrutura , Sítios de Splice de RNA/genética , Proteínas Recombinantes de Fusão/metabolismo , Reprodução , Sementes/citologia , Sementes/metabolismo , Sementes/ultraestrutura , Frações Subcelulares/metabolismo , /metabolismo
14.
Korean J Hepatol ; 17(3): 213-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22102388

RESUMO

BACKGROUND/AIMS: JX-594 is an oncolytic virus derived from the Wyeth vaccinia strain that causes replication-dependent cytolysis and antitumor immunity. Starting with a cross-examination of clinical-trial samples from advanced hepatocellular carcinoma patients having high levels of aldosterone and virus amplification in JX-594 treatment, we investigated the association between virus amplification and aldosterone in human cancer cell lines. METHODS: Cell proliferation was determined by a cell-counting-kit-based colorimetric assay, and vaccinia virus quantitation was performed by quantitative polymerase chain reaction (qPCR) and a viral plaque assay. Also, the intracellular pH was measured using a pH-sensitive dye. RESULTS: Simultaneous treatment with JX-594 and aldosterone significantly increased viral replication in A2780, PC-3, and HepG2 cell lines, but not in U2OS cell lines. Furthermore, the aldosterone treatment time altered the JX-594 replication according to the cell line. The JX-594 replication peaked after 48 and 24 hours of treatment in PC-3 and HepG2 cells, respectively. qPCR showed that JX-594 entry across the plasma membrane was increased, however, the changes are not significant by the treatment. This was inhibited by treatment with spironolactone (an aldosterone-receptor inhibitor). JX-594 entry was significantly decreased by treatment with EIPA [5-(N-ethyl-N-isopropyl)amiloride; a Na(+)/H(+)-exchange inhibitor], but aldosterone significantly restored JX-594 entry even in the presence of EIPA. Intracellular alkalization was observed after aldosterone treatment but was acidified by EIPA treatment. CONCLUSIONS: Aldosterone stimulates JX-594 amplification via increased virus entry by affecting the H(+) gradient.


Assuntos
Aldosterona/farmacologia , Vírus Vaccinia/efeitos dos fármacos , Vírus Vaccinia/fisiologia , Replicação Viral/efeitos dos fármacos , Amilorida/análogos & derivados , Amilorida/farmacologia , Animais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Humanos , Hidrocortisona/sangue , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/virologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Terapia Viral Oncolítica , Coelhos , Espironolactona/farmacologia , Vírus Vaccinia/genética , Vírus Vaccinia/metabolismo
15.
Proc Natl Acad Sci U S A ; 108(5): 2154-9, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21245300

RESUMO

We identify a gene, organ boundary1 (OBO1), by its unique pattern of enhancer- driven GFP expression at the boundaries between the apical meristems and lateral organs in Arabidopsis embryos, seedlings, and mature plants. OBO1 also is expressed at the root apical meristem and in distinct cell files surrounding this area. OBO1 is one of a 10-member plant-specific gene family encoding a single small domain (133 amino acids) with unknown function. One member of this gene family, OBO2, is identical to a previously studied gene, light-sensitive hypocotyl1. Overexpression of OBO1 causes an abnormal number and size of petals and petal-stamen fusions. The patterns of OBO1 gene expression are distinct but overlap with other genes involved in boundary formation in the Arabidopsis shoot apical meristem, including cup-shaped cotyledon, lateral organ boundaries, blade-on-petiole, asymmetric leaves, and lateral organ fusion. Nuclear localization of OBO1 suggests that it might act with one or more of the transcription factors encoded by the foregoing genes. Ablation of the specific cells expressing OBO1 leads to loss of the shoot apical meristem and lateral organs. Thus, the cells expressing OBO1 are important for meristem maintenance and organogenesis in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Arabidopsis/embriologia , Arabidopsis/crescimento & desenvolvimento , Elementos Facilitadores Genéticos , Proteínas de Fluorescência Verde/genética , RNA Mensageiro/genética , Sementes/crescimento & desenvolvimento
17.
Proc Natl Acad Sci U S A ; 102(33): 11945-50, 2005 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-16087887

RESUMO

The axial body pattern of Arabidopsis is determined during embryogenesis by auxin signaling and differential gene expression. Here we demonstrate that another pathway, cell-to-cell communication through plasmodesmata (PD), is regulated during apical-basal pattern formation. The SHOOT MERISTEMLESS (STM) promoter was used to drive expression in the shoot apical meristem (SAM) and a subset of cells at the base of the hypocotyl of 1x,2x, and 3x soluble green fluorescent proteins (sGFPs), and the P30 movement protein of Tobacco mosaic virus (TMV) translationally fused to 1x and 2x sGFP. In the early heart stage, 2x sGFP (54 kDa) moves throughout the whole embryo, whereas 3x sGFP (81 kDa) shows more restricted movement. As the embryo develops, PD apertures are down regulated to form local subdomains allowing transport of different sized tracers. For example, movement of 2x sGFP to the cotyledon, and 3x sGFP to root tips, becomes restricted. Subdomains of cell-to-cell transport align with the apical-basal embryo body axis and correspond to the shoot apex, cotyledons, hypocotyl, and root. Studies with P30-GFP fusions reinforce the distinction between embryonic symplastic subdomains. Although P30 targets embryo cell walls as puncta (diagnostic for functional localization of P30 to PD in adult plants), P30 cannot dilate embryonic PD to overcome the barriers for transport between symplastic subdomains, suggesting that specific boundaries separate symplastic subdomains of the embryo. Thus, cell-to-cell communication via plasmodesmata conveys positional information critical to establish the axial body pattern during embryogenesis in Arabidopsis.


Assuntos
Arabidopsis/embriologia , Arabidopsis/metabolismo , Plasmodesmos/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Transporte Biológico , Padronização Corporal , Genes Reporter/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Movimento , Raízes de Plantas/metabolismo , Plasmodesmos/genética , Fatores de Tempo
18.
Proc Natl Acad Sci U S A ; 102(6): 2227-31, 2005 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-15668382

RESUMO

There is increasing evidence for intercellular trafficking of macromolecules through plasmodesmata (PD) during plant development. Here we study the ability of PD to traffic proteins during embryogenesis and early seedling development in Arabidopsis. Transgenic lines that induce GFP expression only in meristems, MSG (meristem-specific GFP), were used to monitor GFP movement. Cell-to-cell movement of different-sized GFP reporters reveals that embryos and young seedlings traffic proteins at least 54 kDa in size. Although 27-kDa soluble GFP (1 x sGFP) freely moves between cells throughout the entire embryo during all stages analyzed, 2 x sGFP movement becomes more restricted as development proceeds. After germination, cells near the apical meristem in seedlings show a higher size exclusion limit (SEL), whereas the SEL becomes more restricted as surrounding tissues develop identities. Although 1 x sGFP moves throughout leaf primordia, as the leaf develops only the basal part of leaf petioles, main vascular tissues, and leaf veins (not blades) allow 1 x sGFP movement. Although previous studies showed that embryos allow movement of small symplastic tracers (0.5 kDa), the present data demonstrate that the embryo constitutes a single symplast that allows transport of macromolecules as well. Even 2 x sGFP moves from its site of expression at the apical meristem in embryos and seedlings, yet the extent of movement is more limited than 1 x sGFP. Thus, PD have distinct SELs in different subregions of the embryo and seedling. These studies support the general concept that PD in younger tissues are more dilated and less restrictive than PD in older (nonvascular) tissues.


Assuntos
Arabidopsis/embriologia , Arabidopsis/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Transporte Biológico/fisiologia , Proteínas de Fluorescência Verde/genética , Hibridização In Situ , Meristema/citologia , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Plasmodesmos/metabolismo
19.
Hum Gene Ther ; 14(17): 1643-52, 2003 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-14633406

RESUMO

Recombinant adenovirus (Ad) has emerged as the vector system of choice in cancer gene therapy. Its full utility, however, has been limited because of the low efficiency of adenovirus-mediated gene transfer to cancer cells - the main reason being that cancer cells in general express inherently low levels of the coxsackie and adenovirus receptor (CAR) on their surface. Development of novel strategies to achieve adenovirus infection in a CAR-independent manner may help to overcome this limitation. To this end, we have generated a novel recombinant Ad, dl-VSVG-LacZ, that contains a fiber knob with intact CAR entry capability and an additional phosphatidylserine (PS) entry capability. This was achieved by incorporating the vesicular stomatitis virus glycoprotein (VSV-G) epitope onto the C terminus of the fiber knob. VSV-G is an envelope protein that facilitates the specificity for binding of the virus to PS moieties on the cellular plasma membrane. The newly tropism-expanded adenovirus, dl-VSVG-LacZ, showed a remarkable improvement (3- to 20-fold) in the delivery of LacZ to a variety of mammalian cells including those that were CAR deficient. The greatest improvement in gene transfer was observed in cells that were difficult to transduce with an untargeted Ad (wildtype fiber). Furthermore, treatment with dl-VSVG-LacZ significantly enhanced gene transfer in vivo when compared with control adenovirus that lacked the VSV-G epitope. Taken together, these studies demonstrate that the strategy to extend adenovirus tropism may greatly improve the utility of adenovirus in gene therapy applications.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Glicoproteínas/química , Óperon Lac , Vírus da Estomatite Vesicular Indiana/genética , Adenoviridae/genética , Animais , Ligação Competitiva , Membrana Celular/metabolismo , Separação Celular , Dimerização , Epitopos/química , Citometria de Fluxo , Vetores Genéticos , Genótipo , Glicoproteínas/genética , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Plasmídeos/metabolismo , Estrutura Terciária de Proteína
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...