Expression of Tim-3 on Neutrophils as a Novel Indicator to Assess Disease Activity and Severity in Ankylosing Spondylitis

Xuechan Huang ^1* Yuebing He ¹ Guanqun Yi ¹ Shaoling Zheng ¹ Weiming Deng ¹ Shuyang Chen ¹ Ruiqi Zhu ¹ Yunqing Wang ¹ Junming Chen ^1,2 Chun Zheng ¹ Zhixiang Huang ¹ Tianwang Li ^1,2,3*

• ¹ Department of Rheumatology and Immunology, The Affiliated Guangdong Second Provincial General Hospital of Jinan University, Guangzhou, China
• ² The Second School of Clinical Medicine, Southern Medical University, Guangzhou, China
• ³ Department of Rheumatology and Immunology, Zhaoqing Central People’s Hospital, Zhaoqing, China

To investigate the expression of Tim-3 on neutrophils in ankylosing spondylitis (AS) patients and its correlation with disease activity, severity, and inflammatory markers.Sixty-two AS patients from Guangdong Second Provincial General Hospital and 38 healthy controls (HC) were enrolled. Clinical data, physical exams, and laboratory measurements were recorded. Flow cytometry measured Tim-3 and PD-1 expression on neutrophils, real-time PCR quantified mRNA levels and protein expression of Tim-3 was determined by Western blot. We analyzed the correlation between Tim-3 mean fluorescence intensity (MFI) on neutrophils, inflammatory markers, and AS disease activity and severity.Tim-3 expression on neutrophils was higher in AS patients than in HC, showing a positive correlation with erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), and Ankylosing Spondylitis Disease Activity Score (ASDAS). Active AS patients (ASDAS≥1.3) had increased Tim-3 MFI compared to inactive ones (ASDAS<1.3). Regular treatment with non-steroidal anti-inflammatory drugs (NSAIDs), biological disease-modifying anti-rheumatic drugs (bDMARDs), and conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) over a month significantly reduced Tim-3 MFI in AS patients.3Elevated Tim-3 expression on neutrophils correlates with increased inflammatory markers and AS activity. Treatment lowered Tim-3 MFI, suggesting its potential as an indicator for assessing AS disease activity and severity and as a feedback mechanism to reduce tissue damage from inflammation.