Early increase of circulating transitional B cells and autoantibodies to joint-related proteins in patients with metastatic melanoma developing checkpoint inhibitor-induced inflammatory arthritis.

• To investigate potential associations between B cell-related immunological changes and development of inflammatory arthritis (IA) after treatment with immune checkpoint inhibitors (ICI).Patients who developed IA (ICI-IA) and patients who did not develop immune-related adverse events (non-irAE) after receiving ICI due to metastatic melanoma were consecutively recruited. Blood samples were collected at the time of ICI-IA occurrence and at different timepoints during treatment. Peripheral blood B cell subsets during ICI treatment were analyzed by flow cytometry. Rheumatoid factor, autoantibodies against citrullinated peptides and against joint-related proteins were measured.Proportions of CD19+ B cells were higher in patients with ICI-IA (n=7) vs. non-irAE (n=15; median (interquartile range, IQR), %: 11.7 (9.7-16.2) vs. 8.1 (5.7-11.0), p=0.03). The proportion and absolute numbers of transitional CD19+ CD10+ CD24hi CD38hi B cells were increased in patients with ICI-IA vs. non-irAE (median (IQR); %: 8.1 (4.9-12.1) vs. 3.6 (1.9-4.9); cells/μl: 10.7 (8.9-19.6) vs. 4.4 (2.3-6.6), p<0.01 for both), and higher levels of transitional B cells were associated with development of ICI-IA (OR 95% CI: 2.25 (1.03-4.9), p=0.04). Transitional B cells increased before the onset of overt ICI-IA and decreased from active to quiescent ICI-IA (p=0.02). Autoantibodies to collagen II epitopes were detected in up to 43% of ICI-IA patients compared to none of the non-irAE patients (p=0.02).Development of ICI-IA is accompanied by an increase in transitional B cells and by production of autoantibodies to joint-related proteins. Monitoring of B cell-driven abnormalities upon ICI treatment may help earlier recognition of ICI-IA. This article is protected by copyright. All rights reserved.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine (hsv//eng)

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)