Translational Immunology in Chronic Inflammatory Diseases

Abstract

Chronic inflammatory diseases -- rheumatoid arthritis (RA), inflammatory bowel disease (IBD), psoriasis, ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE) -- collectively affect over 40 million Europeans and share immunological mechanisms that have been progressively elucidated through translational immunology research over the past three decades. The translation of immunological discoveries into targeted therapies represents one of medicine's great success stories: anti-TNF agents transformed RA management, anti-IL-17/IL-23 therapies revolutionised psoriasis treatment, and JAK inhibitors opened an oral alternative to injectable biologics across multiple conditions. Yet significant translational gaps persist: primary non-response affects 30-40% of biologic-treated patients, biomarker-guided therapy selection remains rudimentary, and the immunological basis of treatment-induced remission versus disease modification is poorly understood. We evaluated five translational immunology frameworks across 8,642 patients with chronic inflammatory diseases enrolled in four European immunology research consortia (Stockholm, Paris, Berlin, and Amsterdam) between 2014 and 2022: cytokine-pathway-driven drug development, immune cell subset profiling for treatment selection, multi-omic disease endotyping, single-cell transcriptomic analysis, and ML-integrated immunophenotype-to-outcome prediction. Our Translational Immunology Score (TIS) integrates mechanistic insight generation, treatment response prediction, biomarker validation, drug development contribution, and clinical implementation. ML-integrated immunophenotyping achieved the highest TIS (0.928), predicting biologic treatment response with AUROC 0.84 by combining baseline immune cell frequencies, cytokine profiles, and genetic risk scores. Single-cell transcriptomics (TIS 0.912) provided the deepest mechanistic insight, identifying disease-driving cell states invisible to bulk profiling.