Juvenile Sjoegren´s syndrome cases have been reported to be negative for both SS‑A and SS‑B. Therefore, it is necessary to define highly specific autoantibodies characteristic for Sjoegren´s syndrome.
Fodrin is a major actin-binding protein of the eukaryotic cytoskeleton composed of two subunits, an (a-) and a (b-) dimer. During apoptosis, the a‑fodrin dimer is cleaved into a 120 kD subunit, which is present abundantly in the salivary gland. It is unknown how the proteolysis of fodrin is triggered - possibly due to protease activation for unknown reasons during apoptosis. It has been shown, that in Sjoegren´s syndrome patients a‑fodrin is also involved in the stimulation of peripheral blood T‑cells. This aspect implies that an increase of protease activity for unknown reasons and the stimulation of T‑cells are critical for the progression of a‑fodrin proteolysis during the development of primary Sjoegren´s syndrome.
a‑fodrin autoantibodies are specifically detected in sera of adults affected with primary or secondary Sjoegren´s syndrome but they are not found in other autoimmune disorders without sicca symptoms. In contrast to adults, the a‑fodrin antibody is often present in juvenile SLE and juvenile RA without any signs suggesting secondary Sjoegren´s syndrome.
The detection of anti‑a‑fodrin antibodies can prove to be a useful sensitive and specific marker for Sjoegren´s syndrome, particularly during the early stages of the pathogenesis of Sjoegren’s syndrome and even for diagnosis of juvenile SLE and RA. It has been shown that alpha-fodrin antibodies can be detected earlier than SS‑A or SS‑B. Clinical trials indicate that routine screening for a‑fodrin antibodies is a valuable tool for the diagnosis of Sjoegren´s syndrome in adults with sicca symptoms and even for the determination of juvenile Sjoegren´s syndrome, SLE and RA.
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| Tests |
12 x 8 Tests
(break away modules)
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| Calculation |
quantitative
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| Range |
0 – 100 U/ml
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| Cut-off |
IgG / IgA: 10 U/ml |
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| Sensitivity |
IgG / IgA: 1 U/ml |
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| Calibration |
arbitrary
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| Substrate |
TMB / 450 nm
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Instruction for Use: ORG 642-0507-01-gb.pdf
Material-Safety-Datasheet: 642e.pdf