Levels of myeloperoxidase (MPO)-specific anti-neutrophil cytoplasmic autoantibody (ANCA) do not always correlate with disease activity in MPO-ANCA-associated vasculitis (MPO-AAV). Now, data from a new study suggest that a novel anti-moesin autoantibody might also have a role in the pathogenesis of this disease.

Credit: NPG

In this study, Suzuki and colleagues found significantly higher levels of the anti-moesin autoantibody in serum samples from patients with MPO-AAV (n = 60) than in those from healthy controls (n = 31). Among patients with MPO-AAV, levels of serum creatinine, inflammatory cytokines (including IFN-γ and GM-CSF) and chemokines (including MCP-1) were increased in the anti-moesin autoantibody positive group (n = 32). Moreover, levels of IL-7 and IL-12p70 correlated with anti-moesin autoantibody titre in these patients. Based on these and additional data, the researchers speculate that the anti-moesin autoantibody might be involved in the inflammatory response that leads to progression of vasculitis. Consistent with this hypothesis, anti-moesin IgG bound to human neutrophils and monocytes and stimulated the production of IFN-γ, MCP-1, IL-8, IL-17 and GM-CSF in vitro.

“The present study suggested, for the first time, that the anti-moesin autoantibody reacted with neutrophils and monocytes and is associated with the development of small vessel vasculitis,” conclude the researchers.