AB0170 ACTIVATED SENESCENCE PATHWAYS IN THE TEMPORAL ARTERIES OF PATIENTS WITH GIANT CELL ARTERITIS

Background Giant cell arteritis (GCA) is an inflammatory disease marked by granulomatous inflammation of the large- and medium-vessels. GCA exclusively affects older patients above 50 years old, suggesting a role senescence in pathobiology GCA. IL-6 receptor blocking therapy has been shown to be effective treatment for GCA.(1) More recently, phase two randomized control trial efficacy GM-CSF GCA.(2) Both are senescence-associated secretory phenotype (SASP) cytokines,(3) implicating roles cellular SASP immunopathology Objectives We seek find clues senescent inflamed arteries patients. Methods Immunohistochemical stainings markers p21 WAF1/CIP1 p16/INK4A as well SAPS cytokines were performed on temporal artery biopsies (TABs; n=8) from with giant arteritis. Non-inflamed age-matched controls included (n=14). Stainings scored quantitatively using QuPath software. Opal based multiplex fluorescent confirm colocalization GM-CSF. Results All four detected arteries, most notably cells surrounding intimal lamina elastica although expression other was also throughout vessels. The all significantly lower arteries. Cells positive that co-express Conclusion Our data suggest presence activated pathways at site vascular support further research into References [1]Maz M, Chung SA, Abril A, Langford CA, Gorelik Guyatt G, Archer AM, Conn DL, Full KA, Grayson PC, et al. 2021 American College Rheumatology/Vasculitis Foundation Guideline Management Cell Arteritis Takayasu Arteritis. Arthritis Rheumatol 2021; 73:1349–1365. [2]Cid MC, Unizony SH, Blockmans D, Brouwer E, Dagna L, Dasgupta B, Hellmich Molloy Salvarani C, Trapnell BC, Efficacy safety mavrilimumab arteritis: 2, randomised, double-blind, placebo-controlled trial. Ann Rheum Dis 2022; 81:653–661. [3]Coppé JP, Desprez PY, Krtolica Campisi J. Senescence-Associated Secretory Phenotype: Dark Side Tumor Suppression. Annu Rev Pathol 2010; 5:99. Acknowledgements (or more) the/several author(s) this publication is/are (a) member(s) European Reference Network Rare Immunodeficiency, Autoinflammatory Autoimmune Diseases (ERN RITA) Connective Tissue Musculoskeletal ReCONNECT). Disclosure Interests William Febry Jiemy: None declared, Yannick van Sleen: Jacoba Carolien Graver: Sarah A. Pringle: Elisabeth Speakers bureau: EB reports personal fees Roche, outside submitted work., Consultant of: Kornelis der Geest KSMvdG Divi Cornec: Annemieke Boots: Maria Sandovici: declared.