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The ALPHA Cryptococcal Antigen enzyme immunoassay (CrAg EIA) is a qualitative or semi-quantitative (titration) test system for the detection of capsular polysaccharide antigens of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gattii) in serum and cerebrospinal fluid (CSF). The ALPHA Cryptococcal Antigen Enzyme Immunoassay is an assay which can be used as an aid in the diagnosis of cryptococcosis. Test results are to be used in conjunction with information available from the patient clinical evaluation and other diagnostic procedures.

The ALPHA Cryptococcal Antigen Enzyme Immunoassay (EIA) is a direct immunoenzymatic sandwich microplate assay which detects Cryptococcus antigens in serum and CSF. Anti-Cryptococcus antibodies bound to microwell plates are used as capture antibodies, and horseradish peroxidase (HRP)-conjugated anti-Cryptococcus antibodies are used as detect antibodies. The positive control and standard curve material are composed of cryptococcal capsular polysaccharide antigen in a buffered protein solution with a preservative. In the qualitative procedure, specimens are analyzed undiluted. In the titration procedure, specimens are analyzed after serial dilution in specimen diluent. Either serum or CSF is added to the microwells coated with the capture antibodies and incubated. If the patient specimen contains cryptococcal antigens that are recognized by the capture antibodies, those antigens will become bound to the microwells. The microwells are washed to remove unbound patient material, and HRP-conjugated detect antibody is added to the wells. If Cryptococcus antigens are bound to the microwells by the capture antibodies, the detect antibody will also become bound to the microwells. The wells are then washed to remove any unbound detect antibody. Next, tetramethylbenzidine (TMB) substrate is added to the microwells, and in the presence of HRP, a blue color will develop. The reaction is stopped by the addition of a stop solution. The optical density (OD) is determined with a microplate reader at 450 nm with reference at 630 nm (reference is optional).

The Cryptococcal Antigen Lateral Flow Assay (CrAg LFA) is an immunochromatographic test system for the qualitative or semi-quantitative detection of capsular polysaccharide antigens of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gattii) in serum and cerebral spinal fluid (CSF). The CrAg Lateral Flow Assay is a prescription-use laboratory assay, which can aid in the diagnosis of cryptococcosis.

The CrAg Lateral Flow Assay is a dipstick sandwich immunochromatographic assay, which detects cryptococcal antigen in serum and CSF. For the qualitative procedure, specimens are diluted 1:2 in 1x Specimen Diluent and analyzed. For the semi-quantitative procedure, specimens are diluted 1:5 in 1x Specimen Diluent followed by 1:2 serial dilutions. All dilutions are then analyzed as in the qualitative procedure. Specimens are placed into an appropriate reservoir, such as a test tube or microtiter plate, and the lateral flow device is then placed into the reservoir allowing the specimen to come into contact with the test membrane. The test uses specimen wicking to capture gold-conjugated, anti-cryptococcal monoclonal antibodies and gold-conjugated control antibodies that are deposited onto a membrane. If cryptococcal antigen is present in the specimen, it binds to the gold-conjugated, anti-cryptococcal antibodies. The gold-labeled antibody-antigen complex will continue to wick up the membrane where it will interact with the Test Line (T). The Test Line is immobilized anti-cryptococcal monoclonal antibodies. If the specimen contains cryptococcal antigen, a sandwich is created with the gold-labeled antibodies and the immobilized antibodies, causing a visible line to develop at the test line site (T). If proper flow occurs and the reagents are reactive at the time of use, the wicking of any specimen, positive or negative, will cause the gold-conjugated control goat IgG antibody to move to the Control Line (C) which is immobilized bovine anti-goat IgG antibody. The immobilized anti-goat antibody will bind to the gold-conjugated goat IgG Control antibody and will cause a visible line to develop (C). A positive test result will create two lines, while a negative test result will create one line (Figure 1). If the control line fails to develop a line, then the test is not valid.

The CrAg Lateral Flow Assay is an immunochromatographic test system for the qualitative or semi-quantitative detection of capsular polysaccharide antigens of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gatti) in serum. The CrAg Lateral Flow Assay is a prescription-use laboratory assay, which can aid in the diagnosis of Cryptococcosis.

The CrAg Lateral Flow Assay is a dipstick sandwich immunochromatographic assay, which detects cryptococcal antigen in serum. For the qualitative procedure, specimens are diluted 1:2 in 1x Specimen Diluent and analyzed. For the semi-quantitative procedure, specimens are diluted 1:5 in 1x Specimen Diluent followed by 1:2 serial dilutions. All dilutions are then analyzed as in the qualitative procedure. Specimens are placed into an appropriate reservoir, such as a test tube or microtiter plate, and the lateral flow device is then placed into the reservoir allowing the specimen to come into contact with the test membrane. The test uses specimen wicking to capture gold-conjugated, anti-cryptococcal monoclonal antibodies and gold-conjugated control antibodies that are deposited onto a membrane. If cryptococcal antigen is present in the specimen, it binds to the gold-conjugated, anti-cryptococcal antibodies. The gold-labeled antibody-antigen complex will continue to wick up the membrane where it will interact with the Test Line (T). The Test Line is immobilized anti-cryptococcal monoclonal antibodies. If the specimen contains cryptococcal antigen, a sandwich is created with the gold-labeled antibodies and the immobilized antibodies, causing a visible line to develop at the test line site (T). If proper flow occurs and the reagents are reactive at the time of use, the wicking of any specimen, positive or negative, will cause the gold-conjugated control goat IgG antibody to move to the Control Line (C) which is immobilized bovine anti-goat IgG antibody. The immobilized anti-goat antibody will bind to the gold-conjugated goat IgG Control antibody and will cause a visible line to develop (C). A positive test result will create two lines, while a negative test result will create one line (Figure 1). If the control line fails to develop a line, then the test is not valid.

The ALPHA Histoplasma Antigen EIA is an immunoenzymatic sandwich microplate assay for the detection of Histoplasma antigens in urine samples. The ALPHA Histoplasma Antigen EIA is a test which, when used in conjunction with other diagnostic procedures such as microbiological culture, histological examination of biopsy samples and radiographic evidence, can be used as an aid in the diagnosis of histoplasmosis.

The ALPHA Histoplasma Antigen EIA is an immunoenzymatic sandwich microplate assay which detects Histoplasma antigens in urine. Rabbit anti-Histoplasma IgG antibodies bound to microwell plates are used as capture antibodies and biotinylated rabbit anti-Histoplasma IgG antibodies are used as detect antibodies. The positive control is made of buffer spiked with Histoplasma capsulatum antigens and the negative control is buffer only. Standards are made of Histoplasma capsulatum antigens from culture filtrate. The kit contains the 100 Standard, 30 Standard, and 2 Standard that are used to generate a sigmoid calibration curve using a four-parameter fit of the blanked absorbance values versus the assigned EIA Values. R-squared values must be greater than or equal to 0.990. Urine samples are run untreated and undiluted. The samples are added to the microwells coated with the capture antibody and incubated. If the patient specimen contains Histoplasma antigens that are recognized by the capture antibody, those antigens will become bound to the microwell. The wells are washed to remove unbound patient material and biotinylated detection antibody is added to the wells. If Histoplasma antigens are bound to the microwell by the capture antibody, then the detect antibody will also become bound to the microwell. The wells are then washed to remove any unbound detect antibody. For detection, biotin-streptavidin chemistry reagents including 3,3′,5′,5′ tetramethybenzadine (TMB) and stop solution are used. Streptavidin conjugated to horseradish peroxidase (HRP) is added to the microwells. In the presence of the biotinylated detect antibody, streptavidin-HRP will become bound to the plate. The plate is then washed to remove any unbound streptavidin-HRP, and TMB substrate solution is added to the microwells. A blue color develops in the presence of the HRP enzyme. The reaction is stopped by the addition of a stop solution. The optical density (absorbance) is determined with a microplate reader at 450nm or 450nm or 450nm alone. EIA Units for specimens are calculated using a four-parameter curve-fit generated with the 4 standards supplied in the kit.