Photo Credit: Md Babul Hosen
The following is a summary of “Circulating PD-1hi CXCR5- and CXCR5+ CD4 T cells are elevated in patients with newly diagnosed Giant Cell Arteritis and predict relapse,” published in the January 2025 issue of Rheumatology by Monjo et al.
Giant cell arteritis (GCA) is a granulomatous vasculitis involving large/medium vessels. The PD-1/PD-L1 pathway plays a role in its pathogenesis, with elevated frequencies of CD4+CXCR5-PD-1hi peripheral helper (Tph) and CD4+CXCR5+PD-1hi and follicular helper T cells (Tfh) in autoimmune conditions.
Researchers conducted a retrospective study to examine the frequency of circulating Tph (cTph) and Tfh (cTfh) in patients with newly diagnosed GCA (nGCA).
They conducted a prospective, non-interventional study on consecutive patients referred to a GCA fast-track clinic over 24 months. Peripheral blood was collected at initial diagnosis, and PBMCs were isolated using Ficoll-Hypaque. Age- and gender-matched healthy controls (HCs) were included for comparison. Cytometry was used to examine the isolated PBMCs. Patients were treated with standard therapy based on the 2018 EULAR recommendations.
The results showed that 65 patients with nGCA were included. At baseline, patients with nGCA had higher frequencies of cTph and cTfh cells compared to HCs. Among 46 patients followed for 12 months, 19 relapsed. Relapsing patients had significantly lower baseline cTph and cTfh frequencies. A cTph cell frequency <1.0 predicted relapse with 90% sensitivity and 93% specificity.
Investigators found that patients with nGCA had increased baseline cTph and cTfh cell frequencies. Lower baseline proportions of these cells were associated with relapse.
Source: academic.oup.com/rheumatology/advance-article-abstract/doi/10.1093/rheumatology/keaf001/7942512
