Browsing by Author "Li, Lu"

Now showing 1 - 5 of 5
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    ATG5-Dependent Autophagy Uncouples T-cell Proliferative and Effector Functions and Separates Graft-versus-Host Disease from Graft-versus-Leukemia
    (American Association for Cancer Research, 2021) Oravecz-Wilson, Katherine; Rossi, Corinne; Zajac, Cynthia; Sun, Yaping; Li, Lu; Decoville, Thomas; Fujiwara, Hideaki; Kim, Stephanie; Peltier, Daniel; Reddy, Pavan; Medicine, School of Medicine
    Autophagy is a vital cellular process whose role in T immune cells is poorly understood, specifically, in its regulation of allo-immunity. Stimulation of wild-type T cells in vitro and in vivo with allo-antigens enhances autophagy. To assess the relevance of autophagy to T-cell allo-immunity, we generated T-cell-specific Atg5 knock-out mice. Deficiency of ATG5-dependent autophagy reduced T-cell proliferation and increased apoptosis following in vitro and in vivo allo-stimulation. The absence of ATG5 in allo-stimulated T cells enhanced their ability to release effector cytokines and cytotoxic functions, uncoupling their proliferation and effector functions. Absence of autophagy reduced intracellular degradation of cytotoxic enzymes such as granzyme B, thus enhancing the cytotoxicity of T cells. In several in vivo models of allo-HSCT, ATG5-dependent dissociation of T-cell functions contributed to significant reduction in graft-versus-host disease (GVHD) but retained sufficient graft versus tumor (GVT) response. Our findings demonstrate that ATG5-dependent autophagy uncouples T-cell proliferation from its effector functions and offers a potential new strategy to enhance outcomes after allo-HSCT. SIGNIFICANCE: These findings demonstrate that induction of autophagy in donor T-cell promotes GVHD, while inhibition of T-cell autophagy mitigates GVHD without substantial loss of GVL responses.
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    Mitochondrial Complex II In Intestinal Epithelial Cells Regulates T-cell Mediated Immunopathology
    (Springer Nature, 2021) Fujiwara, Hideaki; Seike, Keisuke; Brooks, Michael D.; Mathew, Anna V.; Kovalenko, Ilya; Pal, Anupama; Lee, Ho-Joon; Peltier, Daniel; Kim, Stephanie; Liu, Chen; Oravecz-Wilson, Katherine; Li, Lu; Sun, Yaping; Byun, Jaeman; Maeda, Yoshinobu; Wicha, Max S.; Saunders, Tom; Rehemtulla, Alnawaz; Lyssiotis, Costas A.; Pennathur, Subramaniam; Reddy, Pavan; Microbiology and Immunology, School of Medicine
    Intestinal epithelial cell (IEC) damage by T cells contributes to graft-versus-host disease (GVHD), inflammatory bowel disease (IBD) and immune checkpoint blockade (ICB) mediated colitis. But little is known about the target cell intrinsic features that influence disease severity. Herein we identified disruption of oxidative phosphorylation and an increase in succinate levels in the IECs from several distinct in vivo models of T cell mediated colitis. Metabolic flux studies, complemented by imaging and protein analyses identified disruption of IEC intrinsic succinate dehydrogenase A (SDHA), a component of mitochondrial complex II, in causing these metabolic alterations. The relevance of IEC intrinsic SDHA in mediating disease severity was confirmed by complementary chemical and genetic experimental approaches and validated in human clinical samples. These data identify a critical role for the alteration of the IEC specific mitochondrial complex II component SDHA in the regulation of the severity of T cell mediated intestinal diseases.
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    A multimodality test to guide the management of patients with a pancreatic cyst
    (American Association for the Advancement of Science, 2019-07-17) Springer, Simeon; Masica, David L.; Dal Molin, Marco; Douville, Christopher; Thoburn, Christopher J.; Afsari, Bahman; Li, Lu; Cohen, Joshua D.; Thompson, Elizabeth; Allen, Peter J.; Klimstra, David S.; Schattner, Mark A.; Schmidt, C. Max; Yip-Schneider, Michele; Simpson, Rachel E.; Castillo, Carlos Fernandez-Del; Mino-Kenudson, Mari; Brugge, William; Brand, Randall E.; Singhi, Aatur D.; Scarpa, Aldo; Lawlor, Rita; Salvia, Roberto; Zamboni, Giuseppe; Hong, Seung-Mo; Hwang, Dae Wook; Jang, Jin-Young; Kwon, Wooil; Swan, Niall; Geoghegan, Justin; Falconi, Massimo; Crippa, Stefano; Doglioni, Claudio; Paulino, Jorge; Schulick, Richard D.; Edil, Barish H.; Park, Walter; Yachida, Shinichi; Hijioka, Susumu; van Hooft, Jeanin; He, Jin; Weiss, Matthew J.; Burkhart, Richard; Makary, Martin; Canto, Marcia I.; Goggins, Michael G.; Ptak, Janine; Dobbyn, Lisa; Schaefer, Joy; Sillman, Natalie; Popoli, Maria; Klein, Alison P.; Tomasetti, Cristian; Karchin, Rachel; Papadopoulos, Nickolas; Kinzler, Kenneth W.; Vogelstein, Bert; Wolfgang, Christopher L.; Hruban, Ralph H.; Lennon, Anne Marie; Surgery, School of Medicine
    Pancreatic cysts are common and often pose a management dilemma, because some cysts are precancerous, whereas others have little risk of developing into invasive cancers. We used supervised machine learning techniques to develop a comprehensive test, CompCyst, to guide the management of patients with pancreatic cysts. The test is based on selected clinical features, imaging characteristics, and cyst fluid genetic and biochemical markers. Using data from 436 patients with pancreatic cysts, we trained CompCyst to classify patients as those who required surgery, those who should be routinely monitored, and those who did not require further surveillance. We then tested CompCyst in an independent cohort of 426 patients, with histopathology used as the gold standard. We found that clinical management informed by the CompCyst test was more accurate than the management dictated by conventional clinical and imaging criteria alone. Application of the CompCyst test would have spared surgery in more than half of the patients who underwent unnecessary resection of their cysts. CompCyst therefore has the potential to reduce the patient morbidity and economic costs associated with current standard-of-care pancreatic cyst management practices.
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    Real-world Effectiveness of BNT162b2 Against Infection and Severe Diseases in Children and Adolescent
    (medRxiv, 2023-11-13) Wu, Qiong; Tong, Jiayi; Zhang, Bingyu; Zhang, Dazheng; Chen, Jiajie; Lei, Yuqing; Lu, Yiwen; Wang, Yudong; Li, Lu; Shen, Yishan; Xu, Jie; Bailey, L. Charles; Bian, Jiang; Christakis, Dimitri A.; Fitzgerald, Megan L.; Hirabayashi, Kathryn; Jhaveri, Ravi; Khaitan, Alka; Lyu, Tianchen; Rao, Suchitra; Razzaghi, Hanieh; Schwenk, Hayden T.; Wang, Fei; Witvliet, Margot I.; Tchetgen Tchetgen, Eric J.; Morris, Jeffrey S.; Forrest, Christopher B.; Chen, Yong; Pediatrics, School of Medicine
    Background: The efficacy of the BNT162b2 vaccine in pediatrics was assessed by randomized trials before the Omicron variant's emergence. The long-term durability of vaccine protection in this population during the Omicron period remains limited. Objective: To assess the effectiveness of BNT162b2 in preventing infection and severe diseases with various strains of the SARS-CoV-2 virus in previously uninfected children and adolescents. Design: Comparative effectiveness research accounting for underreported vaccination in three study cohorts: adolescents (12 to 20 years) during the Delta phase, children (5 to 11 years) and adolescents (12 to 20 years) during the Omicron phase. Setting: A national collaboration of pediatric health systems (PEDSnet). Participants: 77,392 adolescents (45,007 vaccinated) in the Delta phase, 111,539 children (50,398 vaccinated) and 56,080 adolescents (21,180 vaccinated) in the Omicron period. Exposures: First dose of the BNT162b2 vaccine vs. no receipt of COVID-19 vaccine. Measurements: Outcomes of interest include documented infection, COVID-19 illness severity, admission to an intensive care unit (ICU), and cardiac complications. The effectiveness was reported as (1-relative risk)*100% with confounders balanced via propensity score stratification. Results: During the Delta period, the estimated effectiveness of BNT162b2 vaccine was 98.4% (95% CI, 98.1 to 98.7) against documented infection among adolescents, with no significant waning after receipt of the first dose. An analysis of cardiac complications did not find an increased risk after vaccination. During the Omicron period, the effectiveness against documented infection among children was estimated to be 74.3% (95% CI, 72.2 to 76.2). Higher levels of effectiveness were observed against moderate or severe COVID-19 (75.5%, 95% CI, 69.0 to 81.0) and ICU admission with COVID-19 (84.9%, 95% CI, 64.8 to 93.5). Among adolescents, the effectiveness against documented Omicron infection was 85.5% (95% CI, 83.8 to 87.1), with 84.8% (95% CI, 77.3 to 89.9) against moderate or severe COVID-19, and 91.5% (95% CI, 69.5 to 97.6)) against ICU admission with COVID-19. The effectiveness of the BNT162b2 vaccine against the Omicron variant declined after 4 months following the first dose and then stabilized. The analysis revealed a lower risk of cardiac complications in the vaccinated group during the Omicron variant period. Limitations: Observational study design and potentially undocumented infection. Conclusions: Our study suggests that BNT162b2 was effective for various COVID-19-related outcomes in children and adolescents during the Delta and Omicron periods, and there is some evidence of waning effectiveness over time.
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    Rearrangement of T Cell genome architecture regulates GVHD
    (Elsevier, 2022-08-06) Sun, Yaping; Dotson, Gabrielle A.; Muir, Lindsey A.; Ronquist, Scott; Oravecz-Wilson, Katherine; Peltier, Daniel; Seike, Keisuke; Li, Lu; Meixner, Walter; Rajapakse, Indika; Reddy, Pavan; Pediatrics, School of Medicine
    WAPL, cohesin's DNA release factor, regulates three-dimensional (3D) chromatin architecture. The 3D chromatin structure and its relevance to mature T cell functions is not well understood. We show that in vivo lymphopenic expansion, and alloantigen-driven proliferation, alters the 3D structure and function of the genome in mature T cells. Conditional deletion of WAPL, cohesin's DNA release factor, in T cells reduced long-range genomic interactions and altered chromatin A/B compartments and interactions within topologically associating domains (TADs) of the chromatin in T cells at baseline. WAPL deficiency in T cells reduced loop extensions, changed expression of cell cycling genes and reduced proliferation following in vitro and in vivo stimulation, and reduced severity of graft-versus-host disease (GVHD) following experimental allogeneic hematopoietic stem cell transplantation. These data collectively characterize 3D genomic architecture of T cells in vivo and demonstrate biological and clinical implications for its disruption by cohesin release factor WAPL.