6 results on '"Vicky Zhang"'
Search Results
2. Characterization of a Dopamine Transporter and Its Splice Variant Reveals Novel Features of Dopaminergic Regulation in the Honey Bee
- Author
-
Vicky Zhang, Robert Kucharski, Courtney Landers, Sashika N. Richards, Stefan Bröer, Rowena E. Martin, and Ryszard Maleszka
- Subjects
biogenic amine ,dopaminergic neurons ,social behavior ,heteromeric protein ,spliced transporter ,DNA methylation ,Physiology ,QP1-981 - Abstract
Dopamine is an important neuromodulator involved in reward-processing, movement control, motivational responses, and other aspects of behavior in most animals. In honey bees (Apis mellifera), the dopaminergic system has been implicated in an elaborate pheromonal communication network between individuals and in the differentiation of females into reproductive (queen) and sterile (worker) castes. Here we have identified and characterized a honey bee dopamine transporter (AmDAT) and a splice variant lacking exon 3 (AmDATΔex3). Both transcripts are present in the adult brain and antennae as well as at lower levels within larvae and ovaries. When expressed separately in the Xenopus oocyte system, AmDAT localizes to the oocyte surface whereas the splice variant is retained at an internal membrane. Oocytes expressing AmDAT exhibit a 12-fold increase in the uptake of [3H]dopamine relative to non-injected oocytes, whereas the AmDATΔex3-expressing oocytes show no change in [3H]dopamine transport. Electrophysiological measurements of AmDAT activity revealed it to be a high-affinity, low-capacity transporter of dopamine. The transporter also recognizes noradrenaline as a major substrate and tyramine as a minor substrate, but does not transport octopamine, L-Dopa, or serotonin. Dopamine transport via AmDAT is inhibited by cocaine in a reversible manner, but is unaffected by octopamine. Co-expression of AmDAT and AmDATΔex3 in oocytes results in a substantial reduction in AmDAT-mediated transport, which was also detected as a significant decrease in the level of AmDAT protein. This down-regulatory effect is not attributable to competition with AmDATΔex3 for ER ribosomes, nor to a general inhibition of the oocyte’s translational machinery. In vivo, the expression of both transcripts shows a high level of inter-individual variability. Gene-focused, ultra-deep amplicon sequencing detected methylation of the amdat locus at ten 5′-C-phosphate-G-3′ dinucleotides (CpGs), but only in 5–10% of all reads in whole brains or antennae. These observations, together with the localization of the amdat transcript to a few clusters of dopaminergic neurons, imply that amdat methylation is positively linked to its transcription. Our findings suggest that multiple cellular mechanisms, including gene splicing and epigenomic communication systems, may be adopted to increase the potential of a conserved gene to contribute to lineage-specific behavioral outcomes.
- Published
- 2019
- Full Text
- View/download PDF
3. High-Affinity Chimeric Antigen Receptor With Cross-Reactive scFv to Clinically Relevant EGFR Oncogenic Isoforms
- Author
-
Radhika Thokala, Zev A. Binder, Yibo Yin, Logan Zhang, Jiasi Vicky Zhang, Daniel Y. Zhang, Michael C. Milone, Guo-li Ming, Hongjun Song, and Donald M. O’Rourke
- Subjects
GBM ,glioma ,immunotherapy ,CAR T cells ,adoptive T cell therapy ,EGFR ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Tumor heterogeneity is a key reason for therapeutic failure and tumor recurrence in glioblastoma (GBM). Our chimeric antigen receptor (CAR) T cell (2173 CAR T cells) clinical trial (NCT02209376) against epidermal growth factor receptor (EGFR) variant III (EGFRvIII) demonstrated successful trafficking of T cells across the blood–brain barrier into GBM active tumor sites. However, CAR T cell infiltration was associated only with a selective loss of EGFRvIII+ tumor, demonstrating little to no effect on EGFRvIII- tumor cells. Post-CAR T-treated tumor specimens showed continued presence of EGFR amplification and oncogenic EGFR extracellular domain (ECD) missense mutations, despite loss of EGFRvIII. To address tumor escape, we generated an EGFR-specific CAR by fusing monoclonal antibody (mAb) 806 to a 4-1BB co-stimulatory domain. The resulting construct was compared to 2173 CAR T cells in GBM, using in vitro and in vivo models. 806 CAR T cells specifically lysed tumor cells and secreted cytokines in response to amplified EGFR, EGFRvIII, and EGFR-ECD mutations in U87MG cells, GBM neurosphere-derived cell lines, and patient-derived GBM organoids. 806 CAR T cells did not lyse fetal brain astrocytes or primary keratinocytes to a significant degree. They also exhibited superior antitumor activity in vivo when compared to 2173 CAR T cells. The broad specificity of 806 CAR T cells to EGFR alterations gives us the potential to target multiple clones within a tumor and reduce opportunities for tumor escape via antigen loss.
- Published
- 2021
- Full Text
- View/download PDF
4. Locally secreted BiTEs complement CAR T cells by enhancing killing of antigen heterogeneous solid tumors
- Author
-
Yibo Yin, Jesse L. Rodriguez, Nannan Li, Radhika Thokala, MacLean P. Nasrallah, Li Hu, Logan Zhang, Jiasi Vicky Zhang, Meghan T. Logun, Devneet Kainth, Leila Haddad, Yang Zhao, Tong Wu, Emily X. Johns, Yu Long, Hongsheng Liang, Jiping Qi, Xiangtong Zhang, Zev A. Binder, Zhiguo Lin, and Donald M. O’Rourke
- Subjects
Pharmacology ,T-Lymphocytes ,Immunotherapy, Adoptive ,Xenograft Model Antitumor Assays ,ErbB Receptors ,Mice ,Cell Line, Tumor ,Drug Discovery ,Interleukin-13 Receptor alpha2 Subunit ,Genetics ,Animals ,Molecular Medicine ,Original Article ,Glioblastoma ,Molecular Biology - Abstract
Bispecific T cell engagers (BiTEs) are bispecific antibodies that redirect T cells to target antigen-expressing tumors. We hypothesized that BiTE-secreting T cells could be a valuable therapy in solid tumors, with distinct properties in mono- or multi-valent strategies incorporating chimeric antigen receptor (CAR) T cells. Glioblastomas represent a good model for solid tumor heterogeneity, representing a significant therapeutic challenge. We detected expression of tumor-associated epidermal growth factor receptor (EGFR), EGFR variant III, and interleukin-13 receptor alpha 2 (IL13Rα2) on glioma tissues and cancer stem cells. These antigens formed the basis of a multivalent approach, using a conformation-specific tumor-related EGFR targeting antibody (806) and Hu08, an IL13Rα2-targeting antibody, as the single chain variable fragments to generate new BiTE molecules. Compared with CAR T cells, BiTE T cells demonstrated prominent activation, cytokine production, and cytotoxicity in response to target-positive gliomas. Superior response activity was also demonstrated in BiTE-secreting bivalent T cells compared with bivalent CAR T cells in a glioma mouse model at early phase, but not in the long term. In summary, BiTEs secreted by mono- or multi-valent T cells have potent anti-tumor activity in vitro and in vivo with significant sensitivity and specificity, demonstrating a promising strategy in solid tumor therapy.
- Published
- 2022
- Full Text
- View/download PDF
5. Do Knowledge and Experience Value Affect Green Tourism Activity Participation and Buying Decision? A Case Study of Natural Dyeing Experience in China
- Author
-
Xiaocheng Vicky Zhang and Suk Ha Grace Chan
- Subjects
Value (ethics) ,media_common.quotation_subject ,theory of planned behaviour ,Geography, Planning and Development ,Purchasing power ,TJ807-830 ,tourist experience ,Management, Monitoring, Policy and Law ,Affect (psychology) ,TD194-195 ,Renewable energy sources ,green tourism ,0502 economics and business ,GE1-350 ,Marketing ,media_common ,Environmental effects of industries and plants ,Renewable Energy, Sustainability and the Environment ,business.industry ,05 social sciences ,Theory of planned behavior ,environmental knowledge ,Environmental sciences ,Escapism ,Environmental education ,Conceptual model ,050211 marketing ,Business ,green purchase intention ,050212 sport, leisure & tourism ,Tourism - Abstract
With the rapid development of niche tourism, green tourism activity has become known to the wider public. By taking into account the extended theory of planned behaviour (TPB), this study takes natural dyeing experience as a case study, with the aim of determining the tourist purchase intention of green products under the destination experience scenario. A quantitative approach was adopted, and 349 valid sets of data were collected from individuals who have participated in natural dyeing activities. Partial least squares–structural equation modelling (PLS–SEM) analysis was conducted to test the conceptual model. The results indicate that experience value (EV) had a significant impact on green purchase conception and intention. In addition, subjective norm had a significant positive influence on tourism green purchase attitude. However, environmental knowledge failed to predict green purchase attitude and perceived behavioural control. The PLS–SEM analysis confirmed the extended TPB model, which showed relatively good predictive validity. Findings suggest that TPB mediated the relationship between EV and purchase intention. The extended model considerably contributes to improving understanding of the impact on green tourism products and dissects theoretical and practical implications to practitioners. Apart from strengthening the experience value from attaining, learning, escapism, and fantasy aspects, on the basis of previous literature, this study concludes that practically, environmental education regarding the experimental environment in tourism destinations in China should return to green activity itself and induce the support of green tourism products. Tourism marketers should trigger personal green knowledge through sense experience in the process of stimulating and promoting green tourism activities, as well as stimulate purchasing power.
- Published
- 2021
- Full Text
- View/download PDF
6. Effects of Psychological Benefits of Greenness on Airlines’ Customer Experiential Satisfaction, Service Fairness, Alternative Attractiveness, and Switching Intention
- Author
-
Suk Ha Grace Chan, Xiaocheng Vicky Zhang, Yifan Betty Wang, and Zhaofeng Mason Li
- Subjects
alternative attractiveness ,experiential satisfaction ,green airlines ,service fairness ,switching intention ,Psychology ,BF1-990 - Abstract
In the context of climate change, this study uncovers the role of green airlines’ social responsibility in conjunction with the consumers’ switching behavior while considering the effects of latent variables, including green psychology, airline corporate image, green experimental behavior, green service fairness, green alternative attractiveness and switching intention, were examined in the study. In a highly competitive service environment, an organization needs to understand how passengers perceive its corporate image, satisfaction, fairness attractiveness, and behavior of switching intention. The predicted relationship was based on partial least squares structural equation modeling of a convenience sample of 615 valid datasets collected from individuals who used green airline services in China. The findings show that the psychological benefit of greenness, only warm glow, is the main driver of airline corporate image. Furthermore, airline corporate image, green service fairness, and green alternative attractiveness support passengers’ green experiential satisfaction. The evidence demonstrates that green experiential satisfaction and green alternative attractiveness have significantly positive effects on switching intention. However, green service fairness has no significant effect on green switching intention. This study contributes to the literature by understanding airline customers’ perception of the complex relationship in the green constructs. This finding can help marketers facilitate and develop their external communication and craft their image to retain their existing or potential customers.
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.