An immuno-DOT diagnostic assay for autoimmune nodopathy

Area of Science:

• Neurology
• Immunology
• Medical Diagnostics

Background:

• Autoimmune nodopathy (AN) is a severe peripheral neuropathy caused by autoantibodies targeting axoglial cell adhesion molecules.
• Accurate detection of autoantibodies against Neurofascin-155 (Nfasc155), PanNeurofascin (PanNfasc), Contactin-1 (CNTN1), and Contactin-associated protein 1 (CASPR1) is crucial for AN diagnosis and monitoring.

Purpose of the Study:

• To develop and validate an immuno-dot assay (immuno-DOT) for routine laboratory use in diagnosing AN.
• To assess the diagnostic performance of immuno-DOT compared to established methods.

Main Methods:

• An immuno-dot assay (immuno-DOT) was developed and its performance evaluated.
• Assay sensitivity and specificity were calculated using a cohort of 58 AN patients and various control groups (50 CIDP, 20 healthy, 30 GBS, 20 MG, 20 CMT).
• Comparison with indirect immunofluorescence, cell-based assays, and ELISA was performed.

Main Results:

• Immuno-DOT demonstrated high sensitivity and specificity for detecting anti-Nfasc155 (91%/97%), anti-PanNfasc (80%/94%), anti-CNTN1 (93%/98%), and anti-CASPR1 (87%/94%) autoantibodies.
• The assay enabled diagnosis within 3 hours and allowed for monitoring immune reactivity and isotype.
• Dot intensity correlated with antibody titers, and results remained reliable after 6 months of storage at -20°C.

Conclusions:

• The immuno-DOT assay exhibits satisfactory diagnostic performance for AN.
• This assay is suitable for routine implementation in medical laboratories, improving AN diagnosis and patient management.