Background Varicella-zoster-virus (VZV) establishes a life-long latent infection with risk of reactivation in patients with autoimmune disorders receiving immunosuppressive/immunomodulatory therapy.
Objectives The study was aimed to evaluate the VZV-specific cellular immune response in the presence of cytokine-blocking antibodies in rheumatoid arthritis (RA) patients and healthy controls (HC).
Methods IFNgamma- and IL-6-producing-CD4+ and -CD8+ T-cells were determined following stimulation with VZV-antigen in the presence of anti-IL-6 or anti-TNFalpha antibodies in vitro. Intracellular cytokine production was determined by flow cytometry in RA patients and HC.
Results No differences in the IFNgamma- and IL-6-producing CD4+ or CD8+ T-cells were found between RA and HC following VZV stimulation. In the presence of anti-IL-6 in vitro, VZV-specific CD4+ T-cells producing IFNgamma reduced in RA compared to HC (11.0% versus 7.9%). In the presence of anti-IL-6, VZV-stimulated cells showed a reduction of IL-6-producing-CD4+ T-cells compared to cells stimulated with VZV alone in RA (7.2% versus 4.8%). No differences were observed in CD8+ T-cells in RA or in CD4+/CD8+ T-cells in HC. In the presence of anti-TNFalpha in vitro, IL-6-producing-CD4+ T-cells of RA patients were lower following stimulation with VZV compared to HC (6.2% versus 9.2%).
Conclusions The reduction of the CD4+ cellular immune response to VZV by blocking of TNFalpha and IL-6 in vitro suggests an important role of inflammatory cytokines in the modulation of the T-cell response to VZV in RA. The influence of different cytokines on the long-term anti-VZV cellular immunity in patients with autoimmune conditions may need further investigated to prevent VZV reactivation.
Disclosure of Interest None declared