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964 citation(s) found for "Zhou, Yu".

Long-Term Remission and Survival in Patients with Rituximab-Refractory/Relapsed B-Cell Non-Hodgkin Lymphoma after Treatment with U16 (CD20 CAR-T cells)
Tan, Jingwen , Liu, Rui , Kang, Liqing , Zhu, Hongjia , Wang, Erhua, Li, Ying , He, Rong , Lou, Xiaoyan, Wang, Wei , Li, Minghao , Gu, Hongfei , Lei, Yu , Cheng, Qian , Zhang, Yi , Zhang, Jian , Xiao, Han , Xu, Nan , Zhou, Yu , Li, Xin

Mayo Clinic

Blood | December 5, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 3447-3447

10.1182/blood-2024-200516 Get It

Background : Rituximab is a monoclonal antibody that targets CD20 and can significantly improve the prognosis of patients with CD20-positive B-cell non-Hodgkin lymphoma (B-NHL). Nonetheless, a significant number of patients experience disease progression or relapse post-rituximab therapy. CD19-chimeric antigen receptor (CAR) T cells have demonstrated remarkable efficacy in B-NHL treatment. However, few studies have focused on the efficacy and safety of CD20 CAR-T cells in rituximab-refractory/relapsed (R/R) B-NHL patients, particularly those treated with rituximab for a short time. Here, we conducted a prospective study, aimed to assess the long-term remission and survival in patients with rituximab-R/R B-NHL after treatment with U16 (CD20 CAR-T cells). Methods : This first-in-human study is an open-label, single center investigator-initiated trial (IIT) to determine the safety and efficacy of CD20 CAR-T in R/R B-NHL after previous rituximab treatment failure (no. ChiCTR2000036350). CD20 CAR-T was administered at a target dose of 1.0×107 CAR-T cells/kg after a 3-day conditioning chemotherapy with fludarabine and cyclophosphamide. The primary objective was to assess the safety and tolerability of CD20 CAR-T. Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were graded according to ASTCT 2019 criteria. The secondary objectives were to evaluate efficacy and pharmacokinetics (PK). Response was assessed per Lugano 2014 criteria. Results:A total of 16 patients with R/R B-NHL were enrolled.The median age was 49 years (range, 28-66). Median number of prior lines of therapy was 3 (range, 2-5). All patients had received rituximab therapy; of these, 9 had done so within the 3 months before CAR-T infusion. CRS occurred in all patients, with 11 patients (68.75%) experiencing grade 1 or 2 CRS and 5 patients (31.25%) experiencing grade 3 CRS. No patient developed grade 4 CRS , and only one patient had ICANS.The most common grade 3 or higher adverse events observed after infusion included leukopenia (93.3%), anemia (40%) and thrombocytopenia (60%). An overall response rate of 100% was observed among enrolled patients, with 11 patients (68.75%) achieving complete remission(CR) and 5 patients (32.25%) achieving partial remission(PR) within 3 months. The median follow-up time was 11.7 months(range 0.69-47.47). The median overall survival was not reached, and the median progression-free survival was 14.5 months. 9 patients remained CR or PR for 12 months, with 7 of them continuing in CR for up to 24 months. The pharmacokinetics of CD20 CAR-T cells were assessed using quantitative PCR to determine the expansion and persistence ability. Peak CAR amplification were detected 7-14 days after infusin. Patients 1, 2 and 4 achieved long-term remission, and persistent positive CAR-T cell copy numbers were detected for 15 months, 30 months and 26 months, respectively. However, patients 7, 8 and 12 relapsed within 3 months, and the CAR-T cell copies of all three patients were reduced to fewer than 1×103 copies/μg of DNA within 3 months. The qPCR results indicated that the maintenance of efficacy was closely related to the persistence of CAR-T cells. Notably, patients who received rituximab less than 3 months before CAR-T infusion had a poorer prognosis, with higher relapse rates (77.8% vs. 28.6%) and shorter progression-free survival, regardless of the degree of response. Conclusion : Long-term follow-up demonstrated that CD20 CAR-T therapy can produce a deep and durable response with a favorable safety profile in patients with rituximab-refractory/relapsed B-NHL. Notably, patients who had received rituximab within 3 months had a poorer prognosis.
Association of Sex, Race and Ethnicity with Clinical Characteristics and Survival Outcomes of Mantle Cell Lymphoma: A National Cancer Database Study
Wang, Jacqueline , Tawfiq, Reema, Okcu, Izel, Ruan, Jia , Martin, Peter , Nowakowski, Grzegorz S. , Wang, Jacqueline F , Tawfiq, Reema K , Okcu, Izel , Zhou, Jihao , Tun, Han W. , Muñoz, Javier , Paludo, Jonas , Moustafa, Muhamad Alhaj , Hwang, Steven R. , Diefenbach, Catherine , Habermann, Thomas M. , Witzig, Thomas E. , Wang, Yucai

Mayo Clinic

Blood | December 5, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 1637-1637

10.1182/blood-2024-204268 Get It

Background Mantle cell lymphoma (MCL) is more common in males, with a male to female ratio of approximately 3:1. However, it is unclear whether disease characteristics and survival outcomes differ by sex. Additionally, the impact of race and ethnicity in MCL is understudied due to underrepresentation of minorities in clinical studies and trials. In this study, we utilized the National Cancer Database (NCDB) to examine patient and disease characteristics and survival outcomes of MCL by sex, race and ethnicity. Methods Patients diagnosed with MCL in 2004-2020 were identified from NCDB. Patient and disease characteristics were compared between groups using Chi-squared tests. Overall survival (OS) analysis was performed using the Kaplan-Meier method and the Cox proportional hazards model. Results A total of 35,135 patients was included. The median follow-up was 83.0 months (95% CI 81.9-84.1). 24,980 (71.1%) patients were male and 10,155 (28.9%) were female. Females had more elderly (age ≥65: 65.9% vs 59.0%; p<0.001), lower Charlson-Deyo Score (CDS ≥2: 7.0% vs 8.6%; p<0.001) and fewer stage III-IV diagnoses (80.5% vs 82.6%; p<0.001). Females were less likely to receive upfront treatment (80.7% vs 85.3%; p<0.001), treatment at academic centers (36.8% vs 40.9%; p<0.001) or transplant (11.0% vs 13.7%; p<0.001). Compared to males, females were more likely to live in metropolitan areas (83.7% vs 81.6%; p<0.001), had similar incomes, had more Medicare (60.4% vs 53.1%) and fewer private insurance (33.2% vs 38.6%; p<0.001). Female patients had better OS, with a median OS of 76.0 (95% CI 72.4-79.6) vs 67.8 months (95% CI 65.9-69.6; p<0.001). In the multivariable Cox model adjusting for age, race, ethnicity, CDS, stage, upfront treatment (vs surveillance or no treatment), facility (academic vs nonacademic), transplant, residence (metropolitan vs urban or rural) and insurance, female sex remained associated with superior OS (HR 0.84, 95% CI 0.793-0.890; p<0.001). For race, 32,399 (92.2%) patients were White, 1,465 (4.2%) were Black, 942 (2.7%) were others and 329 (0.9%) were unknown. Compared to White patients, Black patients had fewer elderly (52.9% vs 61.7%; p<0.001), higher CDS (≥2: 11.4% vs 7.9%; p<0.001), similar stage III-IV (80.7% vs 82.1%; p=0.276) and upfront treatment (84.7% vs 84.0%; p=0.074), were more likely to be treated at academic centers (50.6% vs 38.9%; p<0.001), were less likely to receive transplant (11.1% vs 13.0%; p=0.042), were more likely to live in metropolitan areas (91.0% vs 81.5%; p<0.001), had lower income, had more uninsured (4.4% vs 2.0%) and Medicaid (9.8% vs 3.7%) and fewer Medicare (47.4% vs 56.0%; p<0.001). Black and White patients had similar OS, with a median of 67.9 (95% CI 57.5-78.2) vs 69.6 months (95% CI 67.8 vs 71.3; p=0.697). In the multivariable Cox model, Black vs White race was not associated with OS (HR 1.086, 95% CI 0.952-1.240; p=0.219). For ethnicity, 31,717 (90.3%) patients were non-Hispanic, 1,894 (5.4%) were Hispanic and 1,534 (4.3%) were unknown. Hispanics had fewer elderly (51.3% vs 61.5%; p<0.001), lower CDS (≥2: 6.4% vs 8.2%; p=0.018), similar stage III-IV (81.2% vs 82.1%; p=0.467), were more likely to receive upfront treatment (86.0% vs 83.9%; p<0.001), more likely to be treated at academic centers (49.9% vs 39.5%; p<0.001), equally likely to receive transplant (13.0% vs 13.1%; p=0.943), more likely to live in metropolitan areas (95.4% vs 81.6%; p<0.001), had lower income, had more uninsured (9.6% vs 1.8%) and Medicaid (15.2% vs 9.6%) and fewer Medicare (40.3% vs 55.9%; p<0.001). Hispanics had better OS, with a median OS of 84.4 (95% CI 71.7-97.1) vs 70.5 months (95% CI 68.7-72.2; p<0.001). However, in the multivariable Cox model, Hispanic ethnicity was not associated with OS (HR 0.952, 95% CI 0.839-1.080; p=0.448). Conclusion This study is the first of its scale to demonstrate that female MCL patients have superior survival outcomes compared to males. It also demonstrated that neither Black race nor Hispanic ethnicity appears to be associated with worse survival outcomes. Despite its size, the NCDB is limited in the treatment information and disease characteristics it provides, including MIPI score, Ki-67, blastoid/pleomorphic morphology, and TP53 status. Thus, additional real-world dataset studies are needed to gain a deeper understanding of potential differences in sex, race and ethnicity with regards to disease characteristics and survival outcomes.
Identification of Platelet-Activating Antibodies That Do Not Bind to PF4/Heparin Complexes in Heparin-Induced Thrombocytopenia
Zhou, Lü , Villalobos, Daniel , Aster, Richard H. , Pabmanabhan, Anand, Wen, Renren , Villalobos, Daniel, Wang, Demin

Mayo Clinic

Blood | December 5, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 5588-5588

10.1182/blood-2024-210295 Get It

Heparin-induced thrombocytopenia (HIT) is a severe complication of heparin therapy, driven by IgG antibodies (Abs) that target platelet factor 4 (PF4) bound to heparin, resulting in platelet activation and a pro-thrombotic state. The PF4/Heparin (PF4/H) ELISA is the most commonly used screening assay for HIT due to its wide accessibility and high sensitivity. Despite its limited specificity, resulting in only a small fraction of positive cases progressing to actual HIT, PF4/H ELISA remains a critical tool in initial diagnostics. It is generally believed that HIT patients produce two types of Abs - those that bind to PF4/H and may or may not activate platelets. However, there are documented but rare HIT cases with an atypical profile: Abs testing negative in the PF4/H ELISA (ELISA-) but capable of platelet activation, suggesting the presence of a third type of Abs - those that activate platelets but can't recognize PF4/H complex. Since a PF4/H ELISA- result typically excludes an HIT diagnosis, overseeing these cases could lead to the resumption of heparin, potentially resulting in life-threatening thrombosis. Additionally, in HIT cases with a positive ELISA test profile, or classic HIT cases, levels of platelet-activating Abs and PF4/H-reactive Abs are not always correlated, suggesting the presence of ELISA- platelet-activating Abs. We thus investigated whether ELISA- platelet-activating Abs are present in classic HIT. To identify and characterize ELISA- Abs at the serological level, we firstly purified IgG Abs from the plasma of 5 healthy donors (HD) and 8 HIT patients using protein A beads, followed by the depletion of PF4/H-binding Abs using PF4/H-coated Sepharose beads. The efficiency of IgG purification and PF4/H-specific IgG depletion was confirmed by IgG and PF4/H ELISA. P-selectin expression assay (PEA) was conducted to evaluate the platelet activating ability of purified IgG pre and post depletion of PF4/H-specific Abs. We found that variable, but significant levels of platelet-activating Abs exist in the PF4/H non-reactive IgG portion in all 8 HIT samples, but none of the HD samples. Closely resembling those found in the PF4/H-reactive Abs in HIT patients' plasma, platelet activation induced by post-depletion Abs relied on exogenous PF4 and FcγRIIa and was inhibited by high-dose heparin. These data demonstrate that PF4/H non-reactive IgG Abs coexist with PF4/H-reactive Abs and may contribute to platelet activation in HIT patients. To verify these findings at the clonal level, we conducted single B-cell culture to induce antibody secretion by the cultured B cells from patients experiencing clinical manifestations of HIT. We screened clonal Abs made by 1506 single IgG1+ B cells isolated from peripheral blood mononuclear cells (PBMCs) of seven HIT patients and identified 18 clones capable of platelet activation. Of these, 13 were unable to bind to PF4/H. The functionality of these Abs was confirmed by recombinant Abs derived from single B-cell clones. This finding suggests that PF4/H non-reactive platelet-activating Abs exist at a higher frequency than those that bind to PF4/H. Interestingly, even though these Abs tested negative in the PF4/H ELISA, they were able to bind to the surface of PF4-treated platelets, and their platelet activation ability correlated with platelet binding affinity, suggesting a potential method for their detection. In summary, our study identified a novel group of potentially pathogenic Abs in HIT that, while unable to recognize the PF4/H complex, can bind to the PF4-coated platelet surface. These Abs frequently coexist with PF4/H-binding pathogenic Abs and may contribute to HIT pathogenesis. These insights will enrich our understanding of HIT pathogenesis and may pave the way for more advanced diagnostic and therapeutic strategies.
How to Implement Clinical 7T MRI—Practical Considerations and Experience with Ultra-High-Field MRI
Cramer, Justin , Ikuta, Ichiro , Ikuta, Ichiro , Zhou, Yuxiang

Mayo Clinic

Bioengineering | December 5, 2024 | Volume: 11 | Issue: 12 | Pages: 1228

10.3390/bioengineering11121228 | PMID 39768046 Get It

The implementation of clinical 7T MRI presents both opportunities and challenges for advanced medical imaging. This tutorial provides practical considerations and experiences with 7T MRI in clinical settings. We first explore the history and evolution of MRI technology, highlighting the benefits of increased signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and susceptibility at 7T. Technical challenges such as increased susceptibility artifacts and RF inhomogeneity are also discussed, along with innovative adaptations. This review also discusses hardware and software considerations, including new parallel transmission head coils and advanced image processing techniques to optimize image quality. Safety considerations, such as managing tissue heating and susceptibility to artifacts, are also discussed. Additionally, clinical applications of 7T MRI are examined, focusing on neurological conditions such as epilepsy, multiple sclerosis, and vascular imaging. Emerging trends in the use of 7T MRI for spectroscopy, perfusion imaging, and multinuclear imaging are explored, with insights into the future of ultra-high-field MRI in clinical practice. This review aims to provide clinicians, technologists, and researchers with a roadmap for successfully implementing 7T MRI in both research and clinical environments.
GLP‐1 Receptor Agonists Alleviate Diabetic Kidney Injury via β ‐Klotho‐Mediated Ferroptosis Inhibition
Tian, Shasha , Zhou, Saijun , Wu, Weixi, Lin, Yao , Wang, Tongdan, Sun, Haizhen, Aniwan, Ashanjiang, Li, Yaru , Wang, C. D., Yu, Pei , Zhao, Yanjun , Zhao, Yanjun , Wu, Weixi, Li, Yaru, Li, Xiaogang

Mayo Clinic

Advanced Science | December 4, 2024 | Volume: 12 | Issue: 4 | Pages: No page available

10.1002/advs.202409781 | PMID 39630101 Get It

Abstract Semaglutide (Smg), a GLP‐1 receptor agonist (GLP‐1RA), shows renal protective effects in patients with diabetic kidney disease (DKD). However, the exact underlying mechanism remains elusive. This study employs transcriptome sequencing and identifies β ‐Klotho (KLB) as the critical target responsible for the role of Smg in kidney protection. Smg treatment alleviates diabetic kidney injury by inhibiting ferroptosis in patients, animal models, and HK‐2 cells. Notably, Smg treatment significantly increases the mRNA expression of KLB through the activation of the cyclic adenosine monophosphate (cAMP) signaling pathway, specifically through the phosphorylation of protein kinase A (PKA) and cAMP‐response element‐binding protein (CREB). Subsequently, the adenosine monophosphate‐activated protein kinase (AMPK) signaling pathway is activated, reprograming the key metabolic processes of ferroptosis such as iron metabolism, fatty acid synthesis, and the antioxidant response against lipid peroxidation. Suppression of ferroptosis by Smg further attenuates renal inflammation and fibrosis. This work highlights the potential of GLP‐1RAs and KLB targeting as promising therapeutic approaches for DKD management.
RETRACTED: Targeting mechanistic target of rapamycin complex 2 attenuates immunopathology in systemic lupus erythematosus
Ai, Minji , Jafar‐Nejad, Paymaan , Li, Yanfeng , Gades, Naomi M. , Alexander, Mariam P., Duarte‐García, Alí , Zeng, Hu , Alexander, Mariam P. , Gades, Naomi, Alexander, Mariam P , Bautista-Vargas, Mario, Duarte-García, Alí , Zeng, Hu , Zhou, Xian , Carrer, Michele , Bautista-Vargas, Mario Alejandro

Mayo Clinic

Rheumatology | December 3, 2024 | Volume: 64 | Issue: 6 | Pages: 3964-3974

10.1093/rheumatology/keae662 | PMID 39656824 Get It

Prothrombotic antibodies targeting the spike protein's receptor-binding domain in severe COVID-19
Zhu, Wen , Zheng, Yongwei , Yu, Mei , Witman, Nathan , Zhou, Lu , Wei, Jianhui, Zhang, Yongguang , Nguyen, Christine , Wang, David , Janecke, Rae , Padmanabhan, Anand , White, Gilbert, Fields, Alexander T. , Kornblith, Lucy Z. , Aster, Richard H. , Zhu, Jieqing , Jobe, Shawn M. , Graham, Mary Beth, Wang, Demin , Wen, Renren , Topchyan, Paytsar , Nguyen, Christine , Wang, David , Janecke, Rae , Padmanabhan, Anand , Baumann Kreuziger, Lisa , Hari, Parameswaran , Gu, Tongjun , Kornblith, Lucy Z , Aster, Richard , Zhu, Jieqing , Cui, Weiguo , Jobe, Shawn , Graham, Mary Beth , Wang, Demin , Wen, Renren , Zhou, Lu , Kreuziger, Lisa Baumann , White, Gilbert C., Hari, Parameswaran , Cui, Weiguo

Mayo Clinic

Blood | November 22, 2024 | Volume: 145 | Issue: 6 | Pages: 635-647

10.1182/blood.2024025010 | PMID 39576992 Get It

Abstract Thromboembolic complication is common in severe coronavirus disease 2019 (COVID-19), leading to an investigation into the presence of prothrombotic antibodies akin to those found in heparin-induced thrombocytopenia (HIT). In a study of samples from 130 hospitalized patients, collected 3.6 days after COVID-19 diagnosis, 80% had immunoglobulin G (IgG) antibodies recognizing complexes of heparin and platelet factor 4 (PF4; PF4/H), and 41% had antibodies inducing PF4-dependent P-selectin expression in CpG oligodeoxynucleotide–treated normal platelets. Unlike HIT, both PF4/H-reactive and platelet-activating antibodies were found in patients with COVID-19 regardless of recent heparin exposure. Notably, PF4/H-reactive IgG antibodies correlated with those targeting the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 spike protein. Moreover, introducing exogenous RBD to or removing RBD-reactive IgG from COVID-19 plasma or IgG purified from COVID-19 plasma significantly reduced their ability to activate platelets. RBD-specific antibodies capable of platelet activation were cloned from peripheral blood B cells of patients with COVID-19. These antibodies possessed sequence motifs in the heavy-chain complementarity-determining region 3 (HCDR3), resembling those identified in pathogenic HIT antibodies. Furthermore, IgG+ B cells having these HCDR3 signatures were markedly expanded in patients with severe COVID-19. Importantly, platelet-activating antibodies present in patients with COVID-19 were associated with a specific elevation of platelet α-granule proteins in the plasma and showed a positive correlation with markers for inflammation and tissue damage, suggesting a functionality of these antibodies in patients. The demonstration of functional and structural similarities between certain RBD-specific antibodies in patients with COVID-19 and pathogenic antibodies typical of HIT suggests a novel mechanism by which RBD-specific antibodies might contribute to thrombosis in COVID-19.
Effects of eplontersen on symptoms of autonomic neuropathy in hereditary transthyretin-mediated amyloidosis: secondary analysis from the NEURO-TTRansform trial
Wixner, Jonas, Adams, David , Polydefkis, Michael , Conceição, Isabel , Dyck, P. James B. , Folkvaljon, Folke, Zhou, Wunan , Chen, Jersey , Viney, Nicholas J. , Kwoh, T. Jesse, Coelho, Teresa , Adams, David , Conceição, Isabel , Gillmore, Julian D , Berk, John L. , Attarian, Shahram , Gillmore, Julian D. , Waddington‐Cruz, Márcia

Mayo Clinic

Amyloid | November 18, 2024 | Volume: 32 | Issue: 1 | Pages: 29-38

10.1080/13506129.2024.2427290 | PMID 39552152 Get It

Somatic co‐alteration signatures are prognostic in high‐grade TP53‐mutated myeloid neoplasms
Symes, Emily , Sojitra, Payal , Patel, Anand , Hasan, Faheema , Zhou, Qianghua , Findley, Anthony, Badar, Talha , Tariq, Hamza , Chang, Hong , Bell, Robert , Perry, Anamarija M. , Menon, Madhu P , Patel, Anand , Badar, Talha , Tariq, Hamza , Chang, Hong , Perry, Anamarija M , Venkataraman, Girish , Zhou, Qianghua , Wang, Peng , Ghosh, Sharmila , Roloff, Gregory W. , Findley, Anthony, Zhang, Jingjing

Mayo Clinic

British Journal of Haematology | November 18, 2024 | Volume: 206 | Issue: 4 | Pages: 1103-1108

10.1111/bjh.19895 | PMID 39551719 Get It

SummaryTo assess the relevance of co‐occurring somatic mutations in TP53‐mutated myeloid neoplasms with ≥10% blasts, we pooled 325 individuals from 10 centres. We focused on comparing three published somatic co‐alteration signatures comprising (1) nine MDS‐related genes (‘ICC‐MDSR’), (2) ICC‐MDSR + additional secondary mutations‐related genes (‘Tazi signature’) and (3) EPI6 (comprising six genes). Outcomes examined were 24‐month overall survival (OS24) and front‐line complete response (CR1). The median age was 69 years with 77% receiving front‐line hypomethylating agents (HMA). All three signatures ICC‐MDSR (p = 0.009), Tazi signature (p = 0.001) and EPI6 (p = 0.025) predicted inferior CR1. In the low‐intensity (HMA) subgroup, only Tazi signature (p = 0.026) predicted inferior CR1. In OS24 analysis of the HMA‐treated subgroup (N = 200), only Tazi signature was adverse (hazard ratio, HR = 1.6 [1.1–2.2]; p = 0.011). However, a forward stepwise multivariable age‐adjusted Cox model including all three signatures picked EPI6 as the sole significant adverse predictor in the entire cohort (p = 0.0001) as well as within the HMA‐treated subgroup (p = 0.0071). These data confirm the value of testing co‐occurring somatic alterations even within a high‐grade TP53‐mutated myeloid neoplasm cohort.
Abstract 4140422: Molecular and Functional Characterization of DENND3 as a Novel Regulator of Ion Channel Trafficking
Gao, Shan , Ye, Dan , Tester, David J. , Giudicessi, John, Neves, Raquel , Kim, Changsung, Zhou, Wei Jie , Giudicessi, John R. , Ackerman, Michael

Mayo Clinic

Circulation | November 14, 2024 | Volume: 150 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.150.suppl_1.4140422 Get It

Background: We identified a novel, ultra-rare missense variant (p.R534S) in DENND3 as a potential disease-susceptibility variant in a multi-generational pedigree of familial idiopathic ventricular fibrillation (IVF). DENND3 is a guanine nucleotide exchange factor and activator for small GTPase Rab proteins involved in endosome and ion channel membrane trafficking. However, the role of DENND3 in the heart and its potential involvement in cardiac arrhythmias are unknown. Objective: To functionally characterize DENND3-p.R534S and determine its impact on channel trafficking. Methods: Heterologous co-expression studies in TSA201 cells were performed with DENND3-WT or DENND3-p.R534S and ion channels: KCNQ1 (Kv7.1, IKs), KCNH2 (Kv11.1, IKr), SCN5A (Nav1.5, INa), or CACNA1C (Cav1.2, ICa) as well as Rab proteins (Rab4, Rab5, Rab6, Rab7, Rab11, Rab12). Patient-specific DENND3-p.R534S iPSC-derived cardiomyocytes (iPSC-CMs) and isogenic controls (IC) were created. Localization and expression of ion channel and Rab proteins was assessed using immunofluorescence (IF) by super resolution AiryScan microscopy. GTPase-Glo assays measured Rab protein activity. Electrophysiology studies using patch-clamp and FluoVolt were performed on iPSC-CM models. Results: IF imaging showed significant increases in membrane expression of KCNQ1 (11714±157to 21929±378, p<0.05), KCNH2 (11378±160 to 31965±544, p<0.05), , SCN5A (10339±8 to 11225±23, p<0.05), and CACNA1C (11879±83 to 13749±138, p<0.05) in DENND3-p.R534S compared to DENND3-WT expressing TSA201 cells. Rab5 distribution was altered significantly by the DENND3-p.R534S variant, with increased dispersion away from the nucleus (0.23±0.01 vs. 0.17±0.01, p<0.05) and increased proximity to the plasma membrane (0.16±0.02 vs. 0.23±0.01, p<0.05). Additionally, Rab5 activity was enhanced significantly (57% increase) by p.R534S versus WT (p<0.05). iPSC-CMs revealed similar increases in channel membrane accumulation and irregular arrhythmic activity including frequent action potential duration alternans and afterdepolarizations in 78% of p.R534S iPSC-CMs versus none in IC cells (p<0.05). Conclusion: DENND3 is a novel ion channel trafficking protein in the heart. The DENND3-p.R534S variant disrupts cardiac ion channel trafficking. These findings highlight DENND3’s role in cardiac ion channel distribution, cellular function, and potential association with arrhythmogenic risk.