[HTML][HTML] Regulatory T-cell responses to low-dose interleukin-2 in HCV-induced vasculitis

D Saadoun, M Rosenzwajg, F Joly, A Six… - … England Journal of …, 2011 - Mass Medical Soc
D Saadoun, M Rosenzwajg, F Joly, A Six, F Carrat, V Thibault, D Sene, P Cacoub
New England Journal of Medicine, 2011Mass Medical Soc
Background Patients with vasculitis induced by the hepatitis C virus (HCV) have reduced
levels of regulatory T cells (Tregs). Resolution of HCV infection correlates with cure of
vasculitis and the recovery of Treg levels. We reasoned that interleukin-2, a cytokine that
promotes Treg survival and function, could be beneficial for patients with vasculitis that is
resistant to HCV therapy. Methods We investigated the safety and immunologic effects of the
administration of low-dose interleukin-2 in a prospective open-label, phase 1–phase 2a …
Background
Patients with vasculitis induced by the hepatitis C virus (HCV) have reduced levels of regulatory T cells (Tregs). Resolution of HCV infection correlates with cure of vasculitis and the recovery of Treg levels. We reasoned that interleukin-2, a cytokine that promotes Treg survival and function, could be beneficial for patients with vasculitis that is resistant to HCV therapy.
Methods
We investigated the safety and immunologic effects of the administration of low-dose interleukin-2 in a prospective open-label, phase 1–phase 2a study. Ten patients with HCV-induced vasculitis that was refractory to conventional antiviral therapy, rituximab therapy, or both and who were not receiving glucocorticoid or immunosuppressant therapy received one course of interleukin-2 (1.5 million IU per day) for 5 days, followed by three 5-day courses of 3 million IU per day at weeks 3, 6, and 9. Both the safety of the treatment and its effectiveness were evaluated, the latter by monitoring the Treg response and the clinical signs of HCV vasculitis.
Results
We observed one grade 2 dental abscess that required hospitalization for treatment with antibiotics. Other adverse events were grade 1. The treatment did not induce effector T-cell activation, vasculitis flare, or increased HCV viremia. We observed an improvement of vasculitis in 8 of 10 patients. Administration of low-dose interleukin-2 was followed by an increase in the percentage of CD4+, CD25high, forkhead box P3 (FOXP3+) Tregs [Emax (maximum value)÷baseline value×100=420%] with potent suppressive activity in all subjects and by a concomitantly decreased proportion of marginal-zone B cells. Transcriptome studies of peripheral-blood mononuclear cells revealed that interleukin-2 induced a global attenuation of the signatures for inflammation and oxidative stress mediators.
Conclusions
The trial showed that low-dose interleukin-2 led to Treg recovery and was associated with clinical improvement in 8 of 10 patients with HCV-induced vasculitis, an autoimmune condition. (Funded by the French Agency for Research on AIDS and Viral Hepatitis [ANRS] and others; ClinicalTrials.gov number, NCT00574652.)
The New England Journal Of Medicine