Novel Therapeutic Approach Targeting CXCR3 to Treat Immunotherapy Myocarditis

  • Circ Res. 2025 Feb 28;136(5):473-490. doi: 10.1161/CIRCRESAHA.124.325652.
Yuhsin Vivian Huang  #  1 ,  Yin Sun  #  1 ,  Harrison Chou  1 ,  Noah Wagner  1 ,  Maria Rosaria Vitale  1 ,  Abraham L Bayer  2 ,  Bruce Xu  1 ,  Daniel Lee  3 ,  Zachary Lin  1 ,  Corynn Branche  1 ,  Sarah Waliany  4  5 ,  Joel W Neal  6  7 ,  Heather A Wakelee  6  7 ,  Ronald M Witteles  1  4 ,  Patricia K Nguyen  1  4 ,  Edward E Graves  8 ,  Gerald J Berry  9 ,  Pilar Alcaide  2 ,  Sean M Wu  1  4 ,  Han Zhu  1  4
Affiliations
  • 1. Stanford Cardiovascular Institute, CA (Y.V.H., Y.S., H.C., N.W., M.R.V., B.X., Z.L., C.B., R.M.W., P.K.N., S.M.W., H.Z.).
  • 2. Tufts University School of Medicine, Boston, MA (A.L.B., P.A.).
  • 3. F. Edward Hebert School of Medicine at Uniformed Services University, Bethesda, MD (D.L.).
  • 4. Division of Cardiovascular Medicine, Stanford, CA (S.W., R.M.W., P.K.N., S.M.W., H.Z.).
  • 5. Massachusetts General Hospital Cancer Center, Boston, MA (S.W.).
  • 6. Division of Oncology, Stanford, CA (J.W.N., H.A.W.).
  • 7. Stanford Cancer Institute, CA (J.W.N., H.A.W.).
  • 8. Department of Radiation Oncology, Stanford, CA (E.E.G.).
  • 9. Department of Pathology, Stanford, CA (G.J.B.).
  • # Contributed equally.
PMID: 39931812 DOI: 10.1161/CIRCRESAHA.124.325652
Abstract

Background: Immune checkpoint inhibitors (ICIs) are successful in treating many cancers but may cause immune-related adverse events. ICI-mediated myocarditis has a high fatality rate with severe cardiovascular consequences. Targeted therapies for ICI myocarditis are currently limited.

Methods: We used a genetic mouse model of PD1 deletion (MRL/Pdcd1-/-) along with a novel drug-treated ICI myocarditis mouse model to recapitulate the disease phenotype. We performed single-cell RNA-sequencing, single-cell T-cell receptor Sequencing, and cellular indexing of transcriptomes and epitopes on immune cells isolated from MRL and MRL/Pdcd1-/- mice at serial time points. We assessed the impact of macrophage deletion in MRL/Pdcd1-/- mice, then inhibited CXCR3 (C-X-C motif Chemokine Receptor 3) in ICI-treated mice to assess the therapeutic effect on myocarditis phenotype. Furthermore, we delineated the functional and mechanistic effects of CXCR3 blockade on T-cell and macrophage interactions. We then correlated the results in human single-cell multiomics data from blood and heart biopsy data from patients with ICI myocarditis.

Results: Single-cell multiomics demonstrated expansion of CXCL (C-X-C motif chemokine ligand) 9/10+CCR2+ macrophages and CXCR3hi (C-X-C motif Chemokine Receptor 3 high-expressing) CD8+ (cluster of differentiation) effector T lymphocytes in the hearts of MRL/Pdcd1-/- mice correlating with onset of myocarditis development. Both depletion of CXCL9/10+CCR2+ (C-C motif Chemokine Receptor) macrophages and CXCR3 blockade, respectively, led to decreased CXCR3hi CD8+ T-cell infiltration into the heart and significantly improved survival. Transwell migration assays demonstrated that the selective blockade of CXCR3 and its ligand, CXCL10, reduced CXCR3+CD8+ T-cell migration toward macrophages, implicating this interaction in T-cell cardiotropism toward cardiac macrophages. Furthermore, cardiomyocyte Apoptosis was induced by CXCR3hi CD8+ T cells. Cardiac biopsies from patients with confirmed ICI myocarditis demonstrated infiltrating CXCR3+ T cells and CXCL9+/CXCL10+ macrophages. Both mouse cardiac immune cells and patient peripheral blood immune cells revealed expanded TCRs (T-cell receptors) correlating with CXCR3hi CD8+ T cells in ICI myocarditis samples.

Conclusions: These findings bring forth the CXCR3-CXCL9/10 axis as an attractive therapeutic target for ICI myocarditis treatment, and more broadly as a druggable pathway in cardiac inflammation.

Keywords
T-lymphocytes; chemokines; immune checkpoint inhibitors; macrophages; myocarditis.