|Values are valid only on day of printing.|
Indirect Immunofluorescence Assay (IFA):
Before testing, patient's serum is preabsorbed with liver powder to remove nonorgan-specific autoantibodies. After applying to a composite substrate of frozen mouse tissues (brain, kidney, and gut) and washing, fluorescein-conjugated goat antihuman IgG is applied to detect the distribution and pattern of patient IgG binding.(Pittock SJ, Kryzer TJ, Lennon VA: Paraneoplastic antibodies coexist and predict cancer, not neurological syndrome. Ann Neurol 2004;56:715-719)
Goat antihuman IgG and IgM is used as precipitant in all assays. Cation channel protein antigens are solubilized from neuronal or muscle membrane, in nonionic detergent, and complexed with a selective high-affinity ligand labeled with (125)I. (125)I-labelled recombinant human glutamic acid decarboxylase-65 (GAD65) antigen is used to confirm GAD65 autoantibody (when suspected from immunofluorescent staining pattern).(Griesmann GE, Kryzer TJ, Lennon VA: Autoantibody profiles of myasthenia gravis and Lambert-Eaton myasthenic syndrome. In Manual of Clinical and Laboratory Immunology. Sixth edition. Edited by NR Rose, RG Hamilton, et al. Washington, DC, ASM Press, 2002, pp 1005-1012; Walikonis JE, Lennon VA: Radioimmunoassay for glutamic acid decarboxylase [GAD65] autoantibodies as a diagnostic aid for stiff-man syndrome and a correlate of susceptibility to type 1 diabetes mellitus. Mayo Clin Proc 1998;73:1161-1166)
Western Blot (WB):
WB is performed when IFA screening for antineuronal nuclear antibody-type 1 (ANNA-1) is not interpretable due to interfering autoantibodies. A mixture of neuronal antigens extracted aqueously from adult rat cerebellum is denatured, reduced, and separated by electrophoresis on 10% polyacrylamide gel. Full-length recombinant human CRMP-5 antigen is used to confirm CRMP-5-IgG.(Yu Z, Kryzer TJ, Griesmann GE, et al: CRMP-5 neuronal autoantibody: marker of lung cancer and thymoma-related autoimmunity. Ann Neurol 2001;49:145-154)
Cell Binding Assay (CBA):
Patient serum is applied to a composite slide containing transfected and nontransfected HEK-293 cells. After incubation and washing, fluorescein-conjugated goat antihuman IgG is applied to detect the presence of patient IgG binding.(Package insert: EUROIMMUN AG. Stocker W. et al. Differenzierte Autoantikorper-Diagnostik mit BIOCHIP-Mosaiken. U Conrad, K. [Hrsg] Autoantikorper. Pabst-Verlag  78-99)
ANN1S, ANN2S, ANN3S, AGN1S, PCABP, PCAB2, PCATR, AMPHS, CRMS, AMPIS, GABIS, NMDIS: Monday through Friday; 11 a.m.
AMPCS, GABCS, NMDCS: Monday through Friday; 8 a.m.
Paraneoplastic autoantibody Western blot confirmation, CRMP-5-IgG Western blot, Amphiphysin Western blot: Monday through Friday; 8 a.m.
ARBI: Monday through Saturday; 5 p.m.
CCPQ, CCN: Monday thought Friday; 6 a.m.
GANG, VGKC, GD65S: Sunday through Thursday; 10 p.m.