{
  "abstract": "Background/Objectives A minority of patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have autoantibodies against components of nodal and paranodal structures in peripheral nerves. These autoantibodies are associated with lower likelihood of response to intravenous immunoglobulin (IVIg) treatment and increased responsiveness to B cell depletion. An easily available, reliable diagnostic assay for the detection of nodo-paranodal antibodies is a major unmet need.Methods We tested serum samples from patients with CIDP and healthy controls for the presence of antibodies against neurofascin 155 (NF155), neurofascin 186 (NF186), contactin-1 (CNTN1) and the contactin1/contactin-associated protein 1 (CNTN1/CASPR1) complex using a commercial transfected HEK-293 cell-based indirect immunofluorescence immunoassay (EUROImmun). We modified the manufacturer’s staining protocol using an additional incubation step to increase analytical sensitivity of the assay.Results We detected nodo-paranodal antibodies in four out of 22 CIDP patients, including three who had previously tested positive for nodo-paranodal antibodies using enzyme-linked immunosorbent assay (ELISA), with no positive tests in 52 healthy controls. The modified staining protocol successfully increased the analytical sensitivity of the assay. Our modified assay demonstrated robustness in the presence of common interfering substances and serum with high nonspecific background immunofluorescent staining.Conclusion We successfully modified and validated a commercial indirect immunofluorescence immunoassay for the qualitative detection of antibodies against NF155, CNTN1 and CNTN1/CASPR1. This could lead to more rapid diagnosis of patients with these autoantibodies, avoiding costly and ineffective treatments. Evaluation of the assay in a larger CIDP cohort and disease control group is ongoing. Testing is now available in Australia.",
  "authors": [
    {
      "affiliations": [
        "Department of Clinical Immunology, Pathology East, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia"
      ],
      "name": "Julian Leto"
    },
    {
      "affiliations": [
        "Department of Neurology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia"
      ],
      "name": "Judith Spies"
    },
    {
      "affiliations": [
        "Department of Clinical Immunology, Pathology East, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia"
      ],
      "name": "Linda Tran"
    },
    {
      "affiliations": [
        "Department of Clinical Immunology, Pathology East, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Institute of Academic Medicine, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Faculty of Health and Medicine, University of Sydney, Camperdown, NSW, Australia"
      ],
      "name": "Alex Stoyanov"
    },
    {
      "affiliations": [
        "Department of Clinical Immunology, Pathology East, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Institute of Academic Medicine, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Faculty of Health and Medicine, University of Sydney, Camperdown, NSW, Australia"
      ],
      "name": "Peter Bradhurst"
    },
    {
      "affiliations": [
        "Department of Clinical Immunology, Pathology East, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Institute of Academic Medicine, Royal Prince Alfred Hospital, Camperdown, NSW, Australia",
        "Faculty of Health and Medicine, University of Sydney, Camperdown, NSW, Australia"
      ],
      "name": "Nicolás X Urriola"
    }
  ],
  "title": "3383 Validation and optimisation of a commercial cell-based assay for detection of nodo-paranodal antibodies",
  "uid": "b667090f-abb0-521b-8599-58a0a9df4bd4"
}