Efficiency of long-term treatment with intravenous immunoglobulins correlates with reduced autoreactive T cell responses in chronic inflammatory demyelinating polyneuropathy patients.

Abstract

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare disease of the peripheral nervous system, characterized by gradual increasing weakness of the limbs, with more than 50% of patients experiencing marked disability 1. The underlying pathophysiological mechanism of CIDP remains unknown; however, studies have shown activated T cells in the circulation of CIDP patients 2–4. In addition, patient studies suggest a key role for autoreactive T cell responses against peripheral myelin antigens such as P0, P1, P2 and peripheral myelin protein PMP-22 5,6. Mechanism-of-action studies in other chronic autoimmune diseases have shown that the T cell memory compartment influences antigen responses by showing up-regulation of CD4+ or CD8+ T effector memory (TEM) cells 7,8. Recently, published data from a randomized, placebo-controlled clinical trial demonstrated the long-term efficacy and safety of intravenous immunoglobulin (IVIg) treatment in CIDP patients 9. However, the underlying mechanism of action of IVIg in the treatment of CIDP remains unclear 10,11. The aim of this study was to investigate the course of autoreactive T cell responses against the two peripheral myelin antigens P2 and PMP-22 in addition to the frequency of memory T cell subsets during IVIg treatment in CIDP patients 12.