Immune-cell profiling to guide stratification and treatment of patients with rheumatic diseases.

Methods for high-dimensional immune-cell profiling have advanced dramatically in the past decade. Studies of tissue and blood samples from patients with rheumatic diseases have revealed stereotyped features of immune dysregulation in individual diseases and in subsets of patients who share diagnosis of a heterogeneous disease. Translating immunological patterns into clinically implementable, actionable biomarkers has the potential to improve detection and quantification of pathological immune activity and selection of appropriate treatments for autoimmune rheumatic diseases. For example, cytometric features can be used to distinguish the various forms of inflammatory arthritis, stratify subsets of patients with rheumatoid arthritis or subsets of patients with systemic lupus erythematosus and predict treatment responses. Cellular immune profiling also enables the identification of specific features of immune dysregulation in individuals with rare, undiagnosed, inflammatory diseases. Several paths might lead to translation of discoveries from broad immune profiling into clinical tests to interrogate immune activation in people with rheumatic diseases.