Schwann cells as conditional antigen presenting cells in inflammatory neuropathies

Schwann cells are the myelinating glia cells of the peripheral nervous system ensheathing and supporting axons. In human inflammatory neuropathies like Guillain-Barré syndrome (GBS) an autoimmune response is directed against Schwann cell components. Whether Schwann cells promote this response by presenting autoantigens to T-cells remains controversial.

Here, we show by immunohistochemistry that human Schwann cells in vitro and in vivo indeed express the intracellular machinery required for processing and presenting antigens to autoreactive T-cells. Furthermore, Schwann cells in sural nerve biopsies obtained from patients with GBS increase their expression of antigen associated transport proteins and antigen presenting MHC class I and II complexes.

In coculture experiments rodent Schwann cells activate T-cells when pre-treated with proinflammatory cytokines. These data support the ability of peripheral glia cells to present antigens and its functional relevance. Specifically targeting this pathological function of Schwann cells may in future extend our therapeutic options in GBS.