Detection of CSF 14-3-3 protein in Guillain-Barré syndrome

Objective: To search for biologic markers in the Guillain–Barre´ syndrome (GBS), we studied CSF samples frompatients with GBS and neuropathy of various etiologies for the presence of 14-3-3 protein. Methods: CSF samples frompatients with GBS, chronic neuropathies, motor neuron disease (MND), definite sporadic Creutzfeldt–Jakob disease(sCJD), and normal control subjects were analyzed by standard immunoblot assay, using a polyclonal anti-14-3-3 antibody.CSF samples were also tested with antibodies recognizing specific isoforms of 14-3-3 proteins, either after onedimensionalor two-dimensional electrophoretic separation. Results: A positive 14-3-3 assay was observed in 29 of 38patients with GBS and in 4 patients with MND and other neuropathies, including 2 subjects with vasculitic neuropathy(VN). In GBS, 14-3-3 protein was detected as early as 12 to 48 hours after disease onset and showed an isoform patterndifferent from that encountered in patients with noninflammatory neuropathies, VN, MND, and sCJD. Immunohistochemicalstudies performed in archival fatal GBS cases disclosed marked 14-3-3 expression by mononuclear inflammatoryinfiltrates and Schwann cells. Conclusion: CSF 14-3-3 assay may represent a useful biologic marker in patients withGuillain–Barre´ syndrome.