PhD Scientific Days 2025

Budapest, 7-9 July 2025

Poster Session I. - F: Pharmaceutical Sciences and Health Technologies

Immune Dysregulation in Clozapine-Induced Myocarditis

Előadó neve

Dr. Jakab Márk

Előadó munkahelye

Semmelweis University, Departement of Pharmacology and Pharmacotherapy

Szerző(k) neve és munkahelye

Márk E. Jakab1,2,3,4, Zsombor I. Hegedűs1,2,3,4, Lilla Szabó1,2,3,4, Tamás Kovács1,2,3,4, Andrea Kovács1,2,3,4, Zoltán V. Varga1,2,3,4

1: Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
2: Center for Pharmacology and Drug Research & Development, Budapest, Hungary
3: HCEMM-SU Cardiometabolic Immunology Research Group, Budapest, Hungary
4: MTA-SE Momentum Cardio-Oncology and Cardioimmunology Research Group, Budapest, Hungary

Összefoglaló szövege

Introduction: Pharmacovigilance data identify clozapine, a highly effective antipsychotic for treatment-resistant schizophrenia, as the leading cause of drug-induced myocarditis. No specific treatment exists; discontinuation remains the primary approach, risking psychiatric decompensation. The mechanisms underlying clozapine-induced myocarditis (CIM) remain unclear. Evidence points to eosinophilic infiltration and a Th2-driven immune response, but other factors—including innate lymphoid cells (ILCs) and pro-inflammatory cytokines—may contribute.
Aims: We aimed to characterize the immune alterations in a murine model of CIM, focusing on cytokine expression and immune cell infiltration.
Methods: Male BALB/c mice (8 weeks old) received intraperitoneal injections of clozapine (25 mg/kg or 35 mg/kg) or vehicle control for 21 days. After treatment, cardiac tissue underwent histopathological and transcriptomic analysis to assess inflammatory markers, cytokine gene expression, and leukocyte infiltration.
Results: Clozapine administration induced dose-dependent myocardial inflammation marked by leukocyte infiltration and focal necrosis. Transcriptomic profiling showed increased IL-13, IL-33, and eosinophil-attracting chemokines CCL11 and CCL24 (eotaxins). Elevated IL-17A was also observed, while IFN-γ, TNF-α, and IL-1β remained unchanged.
Conclusion: Our findings indicate that clozapine-induced myocarditis involves immune dysregulation marked by Th2- and Th17-related cytokine signatures without classical pro-inflammatory cytokine upregulation. The concurrent increase in IL-13, IL-33, and eotaxins suggests an eosinophilic and type 2 inflammatory milieu, potentially driven by adaptive and innate lymphoid pathways. This immune profile offers novel mechanistic insights into CIM and a basis for exploring immunomodulatory interventions targeting specific cytokines and cell populations.
Funding: Momentum Research Grant from the Hungarian Academy of Sciences (LP- 2021-38 to ZVV).