Legionella Urinary Antigen (LUA) ELISA Test

The company is launching its Legionella Urinary Antigen (LUA) ELISA Test. The Food and Drug Administration (FDA) has approved this test as an adjunct to culture for the presumptive diagnosis of past or current Legionnaires' Disease by qualitative detection of Legionella pneumophila serogroup 1 antigen in human urine.

The test employs the "antigen sandwich" ELISA design for the detection of Legionella Urinary Antigen. The microelisa wells have been pre-coated with purified rabbit antibodies to Legionella pneumophila Serotype 1 (capture antibody). Undiluted urine specimens are placed in the microelisa wells followed by the immediate addition of Conjugate (horseradish peroxidase-conjugated rabbit antibodies to L. pneumophila). If Legionella Urinary Antigen is present in the specimen, an immune complex is formed between the capture antibody, antigen and conjugate antibody (antigen sandwich), with all three elements being bound to the ELISA plate well. Following incubation, the wells are washed and aspirated to remove unbound antigen and Conjugate. Colorimetric substrate is then added and incubated, followed by the addition of Stop Solution. The stopped plate is then read visually or on a microelisa plate reader. The intensity of the color is directly proportional to the amount of antigen present in the specimen. A positive result is assigned to any specimen whose optical density (O.D.) value is greater than or equal to the Positive Cutoff (4 times the O.D. value of the Negative Control). Alternatively, the results can be visually read using a visual interpretation card, which is provided.

Bartels Inc., 2005 NW Sammamish Rd., Suite 107, Issaquah, WA 98027. Tel: 425-392-2992; Fax: 425-557-1894.