Neuromyelitis optica-IgG detection in serum by indirect immunofluorescence assay / 中华神经科杂志

ABSTRACT

Objective To establish a method to detect neuromyelitis optiea (NMO)-IgG in patients serum using indirect immunofluorescence assay (IFA). Methods The normal tissues (cerebellum/ midbrain, kidney and stomach) from C57 mice were cryosectioned onto microscope slides as detective substrate. For NMO-IgG detection, isolated serum from patient with NMO, multiple sclerosis (MS), optic neuritis or myelitis was incubated with the tissue sections on the slide at 4℃ overnight and subsequently incubated with a fluorochrome-cojugated lgG specific for human. For double immunostaining with aquaporius-4 (AQP4), the slides were incubated with primary antibody of AQP4 and secondary antibody of IgG-TRITC. Detection of NMO-IgG and its co-localization with AQP4 was analyzed using fluorescence microscope. Results All 182 serum samples from patients were tested using IFA. Some samples revealed a characteristic immunohistochemical staining of NMO-IgG in mouse CNS tissues, predominately in pia and subpia, and capillaries in white and grey matter in the cerebellum, midbrain, and spinal cord. Double immunostaining with AQP4 demonstrated the co-localization of NMO-IgG with AQP4. Conclusions We established an IFA using a substrate from C57 mouse cerebellum/midbrain, kidney and stomach tissue to detect NMO-IgG in patient serum. This method is specific and efficient in detection and may be useful in diagnosis and differential diagnosis of neuromyelitis optica.