Browsing by Author "Li, Xiang"

Now showing 1 - 8 of 8
  • Thumbnail Image
    Item
    Acoustofluidic assembly of primary tumor-derived organotypic cell clusters for rapid evaluation of cancer immunotherapy
    (BMC, 2023-02-04) Wu, Zhuhao; Ao, Zheng; Cai, Hongwei; Li, Xiang; Chen, Bin; Tu, Honglei; Wang, Yijie; Lu, Rongze Olivia; Gu, Mingxia; Cheng, Liang; Lu, Xin; Guo, Feng; Medicine, School of Medicine
    Cancer immunotherapy shows promising potential for treating breast cancer. While patients may have heterogeneous treatment responses for adjuvant therapy, it is challenging to predict an individual patient’s response to cancer immunotherapy. Here, we report primary tumor-derived organotypic cell clusters (POCCs) for rapid and reliable evaluation of cancer immunotherapy. By using a label-free, contactless, and highly biocompatible acoustofluidic method, hundreds of cell clusters could be assembled from patient primary breast tumor dissociation within 2 min. Through the incorporation of time-lapse living cell imaging, the POCCs could faithfully recapitulate the cancer-immune interaction dynamics as well as their response to checkpoint inhibitors. Superior to current tumor organoids that usually take more than two weeks to develop, the POCCs can be established and used for evaluation of cancer immunotherapy within 12 h. The POCCs can preserve the cell components from the primary tumor due to the short culture time. Moreover, the POCCs can be assembled with uniform fabricate size and cell composition and served as an open platform for manipulating cell composition and ratio under controlled treatment conditions with a short turnaround time. Thus, we provide a new method to identify potentially immunogenic breast tumors and test immunotherapy, promoting personalized cancer therapy.
  • Thumbnail Image
    Item
    Asian Cohort for Alzheimer's Disease (ACAD) pilot study on genetic and non-genetic risk factors for Alzheimer's disease among Asian Americans and Canadians
    (Wiley, 2024) Ho, Pei-Chuan; Yu, Wai Haung; Tee, Boon Lead; Lee, Wan-Ping; Li, Clara; Gu, Yian; Yokoyama, Jennifer S.; Reyes-Dumeyer, Dolly; Choi, Yun-Beom; Yang, Hyun-Sik; Vardarajan, Badri N.; Tzuang, Marian; Lieu, Kevin; Lu, Anna; Faber, Kelley M.; Potter, Zoë D.; Revta, Carolyn; Kirsch, Maureen; McCallum, Jake; Mei, Diana; Booth, Briana; Cantwell, Laura B.; Chen, Fangcong; Chou, Sephera; Clark, Dewi; Deng, Michelle; Hong, Ting Hei; Hwang, Ling-Jen; Jiang, Lilly; Joo, Yoonmee; Kang, Younhee; Kim, Ellen S.; Kim, Hoowon; Kim, Kyungmin; Kuzma, Amanda B.; Lam, Eleanor; Lanata, Serggio C.; Lee, Kunho; Li, Donghe; Li, Mingyao; Li, Xiang; Liu, Chia-Lun; Liu, Collin; Liu, Linghsi; Lupo, Jody-Lynn; Nguyen, Khai; Pfleuger, Shannon E.; Qian, James; Qian, Winnie; Ramirez, Veronica; Russ, Kristen A.; Seo, Eun Hyun; Song, Yeunjoo E.; Tartaglia, Maria Carmela; Tian, Lu; Torres, Mina; Vo, Namkhue; Wong, Ellen C.; Xie, Yuan; Yau, Eugene B.; Yi, Isabelle; Yu, Victoria; Zeng, Xiaoyi; St. George-Hyslop, Peter; Au, Rhoda; Schellenberg, Gerard D.; Dage, Jeffrey L.; Varma, Rohit; Hsiung, Ging-Yuek R.; Rosen, Howard; Henderson, Victor W.; Foroud, Tatiana; Kukull, Walter A.; Peavy, Guerry M.; Lee, Haeok; Feldman, Howard H.; Mayeux, Richard; Chui, Helena; Jun, Gyungah R.; Ta Park, Van M.; Chow, Tiffany W.; Wang, Li-San; Medical and Molecular Genetics, School of Medicine
    Introduction: Clinical research in Alzheimer's disease (AD) lacks cohort diversity despite being a global health crisis. The Asian Cohort for Alzheimer's Disease (ACAD) was formed to address underrepresentation of Asians in research, and limited understanding of how genetics and non-genetic/lifestyle factors impact this multi-ethnic population. Methods: The ACAD started fully recruiting in October 2021 with one central coordination site, eight recruitment sites, and two analysis sites. We developed a comprehensive study protocol for outreach and recruitment, an extensive data collection packet, and a centralized data management system, in English, Chinese, Korean, and Vietnamese. Results: ACAD has recruited 606 participants with an additional 900 expressing interest in enrollment since program inception. Discussion: ACAD's traction indicates the feasibility of recruiting Asians for clinical research to enhance understanding of AD risk factors. ACAD will recruit > 5000 participants to identify genetic and non-genetic/lifestyle AD risk factors, establish blood biomarker levels for AD diagnosis, and facilitate clinical trial readiness. Highlights: The Asian Cohort for Alzheimer's Disease (ACAD) promotes awareness of under-investment in clinical research for Asians. We are recruiting Asian Americans and Canadians for novel insights into Alzheimer's disease. We describe culturally appropriate recruitment strategies and data collection protocol. ACAD addresses challenges of recruitment from heterogeneous Asian subcommunities. We aim to implement a successful recruitment program that enrolls across three Asian subcommunities.
  • Thumbnail Image
    Item
    Associations of plasma very-long-chain SFA and the metabolic syndrome in adults
    (Cambridge, 2018-10) Zhao, Jing; Li, Xiaofan; Li, Xiang; Chu, Qianqian; Zhou, Yunhua; Li, Zi; Zhang, Hong; Brenna, Thomas J.; Song, Yiqing; Gao, Ying; Epidemiology, School of Public Health
    Plasma levels of very-long-chain SFA (VLCSFA) are associated with the metabolic syndrome (MetS). However, the associations may vary by different biological activities of individual VLCSFA or population characteristics. We aimed to examine the associations of VLCSFA and MetS risk in Chinese adults. Totally, 2008 Chinese population aged 35–59 years were recruited and followed up from 2010 to 2012. Baseline MetS status and plasma fatty acids data were available for 1729 individuals without serious diseases. Among 899 initially metabolically healthy individuals, we identified 212 incident MetS during the follow-up. Logistic regression analysis was used to estimate OR and 95 % CI. Cross-sectionally, each VLCSFA was inversely associated with MetS risk; comparing with the lowest quartile, the multivariate-adjusted OR for the highest quartile were 0·18 (95 % CI 0·13, 0·25) for C20 : 0, 0·26 (95 % CI 0·18, 0·35) for C22 : 0, 0·19 (95 % CI 0·13, 0·26) for C24 : 0 and 0·16 (0·11, 0·22) for total VLCSFA (all Pfor trend<0·001). The associations remained significant after further adjusting for C16 : 0, C18 : 0, C18 : 3n-3, C22 : 6n-3, n-6 PUFA and MUFA, respectively. Based on follow-up data, C20 : 0 or C22 : 0 was also inversely associated with incident MetS risk. Among the five individual MetS components, higher levels of VLCSFA were most strongly inversely associated with elevated TAG (≥1·7 mmol/l). Plasma levels of VLCSFA were significantly and inversely associated with MetS risk and individual MetS components, especially TAG. Further studies are warranted to confirm the findings and explore underlying mechanisms.
  • Thumbnail Image
    Item
    DAG-based Task Orchestration for Edge Computing
    (IEEE, 2022) Li, Xiang; Abdallah, Mustafa; Suryavansh, Shikhar; Chiang, Mung; Bagchi, Saurabh; Engineering Technology, Purdue School of Engineering and Technology
    Edge computing promises to exploit underlying computation resources closer to users to help run latency-sensitive applications such as augmented reality and video analytics. However, one key missing piece has been how to incorporate personally owned, unmanaged devices into a usable edge computing system. The primary challenges arise due to the heterogeneity, lack of interference management, and unpredictable availability of such devices. In this paper we propose an orchestration framework IBDASH, which orchestrates application tasks on an edge system that comprises a mix of commercial and personal edge devices. IBDASH targets reducing both end-to-end latency of execution and probability of failure for applications that have dependency among tasks, captured by directed acyclic graphs (DAGs). IBDASH takes memory constraints of each edge device and network bandwidth into consideration. To assess the effectiveness of IBDASH, we run real application tasks on real edge devices with widely varying capabilities. We feed these measurements into a simulator that runs IBDASH at scale. Compared to three state-of-the-art edge orchestration schemes and two intuitive baselines, IBDASH reduces the end-to-end latency and probability of failure, by 14% and 41% on average respectively. The main takeaway from our work is that it is feasible to combine personal and commercial devices into a usable edge computing platform, one that delivers low and predictable latency and high availability.
  • Thumbnail Image
    Item
    Evaluation of cancer immunotherapy using mini-tumor chips
    (Ivyspring International, 2022-05-01) Ao, Zheng; Cai, Hongwei; Wu, Zhuhao; Hu, Liya; Li, Xiang; Kaurich, Connor; Gu, Mingxia; Cheng, Liang; Lu, Xin; Guo, Feng; Pathology and Laboratory Medicine, School of Medicine
    Rationale: Predicting tumor responses to adjuvant therapies can potentially help guide treatment decisions and improve patient survival. Currently, tumor pathology, histology, and molecular profiles are being integrated into personalized profiles to guide therapeutic decisions. However, it remains a grand challenge to evaluate tumor responses to immunotherapy for personalized medicine. Methods: We present a microfluidics-based mini-tumor chip approach to predict tumor responses to cancer immunotherapy in a preclinical model. By uniformly infusing dissociated tumor cells into isolated microfluidic well-arrays, 960 mini-tumors could be uniformly generated on-chip, with each well representing the ex vivo tumor niche that preserves the original tumor cell composition and dynamic cell-cell interactions and autocrine/paracrine cytokines. Results: By incorporating time-lapse live-cell imaging, our mini-tumor chip allows the investigation of dynamic immune-tumor interactions as well as their responses to cancer immunotherapy (e.g., anti-PD1 treatment) in parallel within 36 hours. Additionally, by establishing orthotopic breast tumor models with constitutive differential PD-L1 expression levels, we showed that the on-chip interrogation of the primary tumor's responses to anti-PD1 as early as 10 days post tumor inoculation could predict the in vivo tumors' responses to anti-PD1 at the endpoint of day 24. We also demonstrated the application of this mini-tumor chip to interrogate on-chip responses of primary tumor cells isolated from primary human breast and renal tumor tissues. Conclusions: Our approach provides a simple, quick-turnaround solution to measure tumor responses to cancer immunotherapy.
  • Thumbnail Image
    Item
    Rapid Profiling of Tumor-Immune Interaction Using Acoustically Assembled Patient-Derived Cell Clusters
    (Wiley, 2022) Ao, Zheng; Wu, Zhuhao; Cai, Hongwei; Hu, Liya; Li, Xiang; Kaurich, Connor; Chang, Jackson; Gu, Mingxia; Cheng, Liang; Lu, Xin; Guo, Feng; Pathology and Laboratory Medicine, School of Medicine
    Tumor microenvironment crosstalk, in particular interactions between cancer cells, T cells, and myeloid‐derived suppressor cells (MDSCs), mediates tumor initiation, progression, and response to treatment. However, current patient‐derived models such as tumor organoids and 2D cultures lack some essential niche cell types (e.g., MDSCs) and fail to model complex tumor‐immune interactions. Here, the authors present the novel acoustically assembled patient‐derived cell clusters (APCCs) that can preserve original tumor/immune cell compositions, model their interactions in 3D microenvironments, and test the treatment responses of primary tumors in a rapid, scalable, and user‐friendly manner. By incorporating a large array of 3D acoustic trappings within the extracellular matrix, hundreds of APCCs can be assembled within a petri dish within 2 min. Moreover, the APCCs can preserve sensitive and short‐lived (≈1 to 2‐day lifespan in vivo) tumor‐induced MDSCs and model their dynamic suppression of T cell tumor toxicity for up to 24 h. Finally, using the APCCs, the authors succesully model the combinational therapeutic effect of a multi‐kinase inhibitor targeting MDSCs (cabozantinib) and an anti‐PD‐1 immune checkpoint inhibitor (pembrolizumab). The novel APCCs may hold promising potential in predicting treatment response for personalized cancer adjuvant therapy as well as screening novel cancer immunotherapy and combinational therapy.
  • Thumbnail Image
    Item
    Reactive oxygen species reprogram macrophages to suppress antitumor immune response through the exosomal miR-155-5p/PD-L1 pathway
    (BMC, 2022-01-27) Li, Xiang; Wang, Shaomin; Mu, Wei; Barry, Jennifer; Han, Anna; Carpenter, Richard L.; Jiang, Bing‑Hua; Peiper, Stephen C.; Mahoney, Mỹ G.; Aplin, Andrew E.; Ren, Hong; He, Jun; Biochemistry and Molecular Biology, School of Medicine
    Background: Cancer cells have an imbalance in oxidation-reduction (redox) homeostasis. Understanding the precise mechanisms and the impact of the altered redox microenvironment on the immunologic reaction to tumors is limited. Methods: We isolated exosomes from ovarian cancer cells through ultracentrifuge and characterized by Western-blots and Nanoparticle Tracking Analysis. 2D, 3D-coculture tumor model, and 3D live cell imaging were used to study the interactions between tumor cells, macrophages and CD3 T cells in vitro. The role of exosomal miR-155-5p in tumor growth was evaluated in xenograft nude mice models and immune-competent mice models. Flow cytometry and flow sorting were used to determine the expression levels of miR-155-5p and PD-L1 in ascites and splenic macrophages, and the percentages of CD3 T cells subpopulations. Results: The elevation of reactive oxygen species (ROS) greatly downregulated exosomal miR-155-5p expression in tumor cells. Neutralization of ROS with N-acetyl-L-cysteine (NAC) increased the levels of miR-155-5p in tumor exosomes that were taken up by macrophages, leading to reduction of macrophage migration and tumor spheroid infiltration. We further found that programmed death ligand 1 (PD-L1) is a functional target of miR-155-5p. Co-culture of macrophages pre-treated with NAC-derived tumor exosomes or exosomal miR-155-5p with T-lymphocytes leading to an increased percentage of CD8+ T-lymphocyte and a decreased CD3+ T cell apoptosis through PD-L1 downregulation. Tumor growth in nude mice was delayed by treatment with NAC-derived tumor exosomes. Delivery of tumor exo-miR-155-5p in immune-intact mice suppressed ovarian cancer progression and macrophage infiltration, and activated CD8+ T cell function. It is of note that exo-miR-155-5p inhibited tumor growth more potently than the PD-L1 antibody, suggesting that in addition to PD-L1, other pathways may also be targeted by this approach. Conclusions: Our findings demonstrate a novel mechanism, ROS-induced down-regulation of miR-155-5p, by which tumors modulate the microenvironment that favors tumor growth. Understanding of the negative impact of ROS on the tumor immune response will improve current therapeutic strategies. Targeting miR-155-5p can be an alternative approach to prevent formation of an immunosuppressive TME through downregulation of PD-L1 and other immunosuppressive factors.
  • Thumbnail Image
    Item
    A regulatory insertion-deletion polymorphism in the FADS gene cluster influences PUFA and lipid profiles among Chinese adults: a population-based study
    (Oxford, 2018-06) Li, Peiqin; Zhao, Jing; Kothapalli, Kumar S. D.; Li, Xiang; Li, Hui; Han, Yuxuan; Mi, Shengquan; Zhao, Wenhua; Li, Qizhai; Zhang, Hong; Song, Yiqing; Brenna, J. Thomas; Gao, Ying; Epidemiology, School of Public Health
    Background Arachidonic acid (AA) is the major polyunsaturated fatty acid (PUFA) substrate for potent eicosanoid signaling to modulate inflammation and thrombosis and is controlled in part by tissue abundance. Fatty acid desaturase 1 (FADS1) catalyzes synthesis of omega-6 (n–3) AA and n–3 eicosapentaenoic acid (EPA). The rs66698963 polymorphism, a 22-base pair (bp) insertion-deletion 137 bp downstream of a sterol regulatory element in FADS2 intron 1, mediates expression of FADS1 in vitro, as well as exerting positive selection in several human populations. The associations between the polymorphism rs66698963 and plasma PUFAs as well as disease phenotypes are unclear. Objective This study aimed to evaluate the relation between rs66698963 genotypes and plasma PUFA concentrations and blood lipid profiles. Design Plasma fatty acids were measured from a single sample obtained at baseline in 1504 healthy Chinese adults aged between 35 and 59 y with the use of gas chromatography. Blood lipids were measured at baseline and a second time at the 18-mo follow-up. The rs66698963 genotype was determined by using agarose gel electrophoresis. Linear regression and logistic regression analyses were performed to assess the association between genotype and plasma PUFAs and blood lipids. Results A shift from the precursors linoleic acid and α-linolenic acid to produce AA and EPA, respectively, was observed, consistent with FADS1 activity increasing in the order of genotypes D/D to I/D to I/I. For I/I compared with D/D carriers, plasma concentrations of n–6 AA and the ratio of AA to n–3 EPA plus docosahexaenoic acid (DHA) were 57% and 32% higher, respectively. Carriers of the deletion (D) allele of rs66698963 tended to have higher triglycerides (β = 0.018; SE: 0.009; P = 0.05) and lower HDL cholesterol (β = −0.008; SE: 0.004; P = 0.02) than carriers of the insertion (I) allele. Conclusions The rs66698963 genotype is significantly associated with AA concentrations and AA to EPA+DHA ratio, reflecting basal risk of inflammatory and related chronic disease phenotypes, and is correlated with the risk of dyslipidemia.