INTENDED USE

The Canine Acetylcholine Binding Receptor Antibody Kit is a radioimmunoassay for the in-vitro-diagnostic semi-quantitative determination of acetylcholine receptor (AChR) binding antibodies (Ab) against the acetylcholine receptor in dog serum. The Canine Acetylcholine Receptor Antibody Kit is useful as an aid in the differential diagnosis of Myasthenia Gravis (MG) in conjunction with other clinical and laboratory findings.

SUMMARY AND EXPLANATION

Myasthenia Gravis is a skeletal muscle disorder characterized by muscular weakness. A good correlation is observed between the presence of AChR Ab and muscle weakness in individual canine patients. There are three types of AChR Ab which have been identified. There are binding, blocking, and modulating antibodies. Binding AChR Ab are multitudes of wide populations of Ab directed to hydrophilic domains of AChRs. Blocking AChR Ab prevent the binding of acetylcholine to AChRs. Modulating AChR Ab accelerate endocytosis which results in the loss of AChRs.

TEST PRINCIPLE

Binding AChR Ab are detected by a radio-binding assay. Canine patient specimens and references are incubated with detergent-solubilized fetal and adult ¹²⁵I-?-bungarotoxin labeled AChRs. After incubation, complexes of labeled AChRs and AChR Ab are immunoprecipitated with anti-dog IgG. The immunoprecipitated complexes are then washed, centrifuged, and aspirated. This leaves a pellet containing labeled AChR-AChRAb complexes. The pellet is counted on a gamma counter. The counts are directly proportional to the amount of AChRAb present in the sample.