SeraSpot® Anti-Yersinia-6 IgA / IgG

Intended use:

The SeraSpot® Anti-Yersinia-6 IgG / SeraSpot® Anti-Yersinia-6 IgA test is an in vitro diagnostic device (spotimmunoassay, SIA) for the detection of Yersinia-specific IgG or IgA antibodies in human serum, plasma or synovial fluid samples. It can be used as screening assay as well as confirmatory assay after a positive ELISA result.

General information:

The genus Yersinia comprises gram-negative bacteria belonging to the family Enterobacteriaceae. There are at least three Yersinia species which are pathogenic to human: Y. pestis, Y. pseudotuberculosis and Y. enterocolitica. More than 60 serovariants are known from Y. enterocolitica (6, 11). The infection of humans is transmitted by the consumption of contaminated meat or sausages, unpasteurized milk or contaminated drinking water. The transmission by direct contact from person to person is rather seldom. The pathogens enter the Peyer´s patches of the small intestine, disseminate to lymphoid tissues and initiate a humoral immune response. In the first 2-3 weeks after the infection IgA and IgM class antibodies are dominating, then IgG antibodies are mainly detectable, which usually persist for several years. In cases of immunopathological complications and chronic forms of Yersinia infections IgA antibodies are detectable for a longer period of time. In patients with reactive arthritis IgA antibodies to specific Yersinia antigens may persist for up to 1 year. In these patients the corresponding antibody class is also detectable in the synovial fluid.

The human pathogenic Yersinia species are characterized by a 70 kb plasmid encoding for cytosolic, membraneous and releasing proteins. The main virulence markers are the Yersinia outer proteins (Yop) which are released by the bacteria. These proteins are highly immunogenic and induce the generation of specific antibodies of the IgA, IgG and IgM isotype. Although no precise data are available the assumed incubation period for Y. enterocolitica ranges from 2 to 10 days. Many mammalian species are known to serve as reservoir hosts, but rodents,
domestic and farm animals are of major epidemiological importance.

The clinical symptoms of an infection with Y. enterocolitica and Y. pseudotuberculosis are very similar. The clinical spectrum of Yersinia enterocolitica infections comprises acute intestinal symptoms (enterocolitis, watery diarrhea) as well as extra intestinal complications like reactive arthritis, Erythema nodosum and Reiter´s syndrome as late sequelae of Yersinia enteritis. In infants an infection induces a self-limiting gastroenteritis frequently accompanied by fever and vomiting. Juveniles often react with a lymphadenitis characterized by abdominal pain often mistaken as appendicitis.

Test principle:

The SeraSpot® Anti-Yersinia-6 IgG / SeraSpot® Anti-Yersinia-6 IgA test is a solid phase immunoassay based on the use of recombinant Yersinia proteins as capture antigens printed in array arrangement (spot array) on the bottom of the wells of 96-well microtiter plates. The recombinant antigens serve as capture molecules for antibodies against Yersinia antigens. Bound antibodies are detected by horseradish peroxidase-(HRP)-labeled antibodies against human antibodies of IgG- or IgA-type by substrate reaction with hydrogen peroxide and 3,3’,5,5’-tetramethylbenzidine (TMB). At the site of formed immune complexes blue spots are developed by precipitated product from colorless substrate solution. Color intensity is correlated to the antibody concentration. Pale blue to dark blue spots are visible by eye.

Art. No.:

• SP-005-6 G-S6 (1×48) / SP-005-6 G-S12 (1×96)
• SP-005-6 M-S6 (1×48) / SP-005-6 M-S12 (1×96)