Tropomyosin autoantibodies associated with checkpoint inhibitor myositis

Pauline Zaenker; David Prentice; Melanie Ziman

doi:10.1080/2162402X.2020.1804703

Tropomyosin autoantibodies associated with checkpoint inhibitor myositis

Oncoimmunology. 2020 Aug 12;9(1):1804703. doi: 10.1080/2162402X.2020.1804703.

Authors

Pauline Zaenker¹, David Prentice², Melanie Ziman^{1

3}

Affiliations

¹ School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.
² General Medicine Department, St John of God Midland Public Hospital, Midland, Australia.
³ Department of Biomedical Science, The University of Western Australia, Perth, Australia.

Abstract

This brief report details the measurement and identification of IgA antibodies to tropomyosin in a case of presumed ocular myositis with paraspinal myositis in a patient with metastatic uveal melanoma treated with checkpoint inhibitors. High-throughput functional protein microarray analysis and pathway analysis was conducted to identify IgG and IgA antibodies of interest. Antibody levels were compared to generic antibody screening results and levels of the antibodies in a cohort of melanoma patients without myositis (n = 100) at baseline prior to undergoing immunotherapy. The finding of specific muscle antibodies in this clinical case indicates the pathogenic potential of anti-tropomyosin IgA in the development of checkpoint inhibitor associated myositis and requires further investigation.

Keywords: Tropomyosin; autoantibody; immunotherapy; myositis; ocular melanoma.

Publication types

Case Reports
Research Support, Non-U.S. Gov't

MeSH terms

Autoantibodies
Humans
Melanoma* / drug therapy
Myositis*
Tropomyosin
Uveal Neoplasms*

Substances

Autoantibodies
Tropomyosin

Grants and funding

This project was funded by the Tour the Cure grant awarded to MZ and the ECU Early Career Researcher Grant (G1004452) awarded to PZ. The author PZ received ongoing financial support as part of the ECU Vice-Chancellor’s Fellowship at Edith Cowan University.