Conclusion
Detection of antibodies against 14-3-3 proteins at the time of LVV diagnosis is not disease-specific. Their presence at high levels in LVV patients with stroke, aortitis and-in a previous study-aneurysm formation may indicate an association with extensive tissue destruction. The relevance of 14-3-3 antibodies in non-LVV patients needs to be investigated in larger cohorts.
Methods
Antibodies against three isoforms of 14-3-3 (γ, ɛ and ζ) were measured in 90 subjects: 48 GCA and 3 Takayasu's arteritis (TA) patients, and 39 controls (non-inflammatory and inflammatory diseases), using a multiplexed bead-based immunoassay and immunoprecipitation studies. The positive cut-off value was defined based on young healthy controls. Anti-14-3-3 IgG antibodies in LVV patients were compared with those in controls in order to assess their diagnostic performance, and the relationship of anti-14-3-3 IgG antibodies to the immunohistopathology of artery explants was assessed.
Results
Antibodies against all three 14-3-3 isoforms were detected in LVV patients as well as in age-matched inflammatory and non-inflammatory controls. Among LVV patients, detection of antibodies targeting 14-3-3 ɛ and ζ was associated with more severe disease. Detection of antibodies against 14-3-3 γ was linked to latent Toxoplasma gondii infection, a parasite that secrets a 14-3-3 homologue, suggesting potential cross-reactivity.