Immunofluorescent assay

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Immunofluorescent assay (IFA)

A blood test sometimes used to confirm ELISA results instead of using the Western blotting. In an IFA test, HIV antigen is mixed with a fluorescent compound and then with a sample of the patient's blood. If HIV antibody is present, the mixture will fluoresce when examined under ultraviolet light.
Mentioned in: AIDS Tests
References in periodicals archive ?
Antibodies to phases I and II are measured using an immunofluorescent assay technique.
We used 3 testing approaches: culture, PCR, and indirect immunofluorescent assays for serologic testing.
Serologic confirmation involves a two-test approach with a sensitive enzyme immunoassay or immunofluorescent assay and a Western immunoblot for IgG and 1gM antibodies.
Anti-HHV-8 antibodies were sought using a standardized indirect immunofluorescent assay, according to the manufacturer's protocol (HHV-8 immunoglobulin G [IgG] indirect immunofluorescent assay kit, Biotrin International Ltd, Dublin, Ireland).
The standard method employs either an enzyme-linked immunosorbent assay (ELISA) or an immunofluorescent assay (IFA) followed by a Western blot in positive or equivocal specimens.
Isolation of SFTSV also was confirmed by indirect immunofluorescent assay (IFA) (Figure 1, panels A,B) and electron microscopy (Figure 1, panel C).
Serological tests, such as indirect immunofluorescent assay (IFA), enzyme immunoassay (EIA) and polymerase chain reaction (PCR), have produced satisfactory results.
We performed affinity extraction as described (8), as was sandwich 2-step immunofluorescent assay (IFA) (8).
These protocols recommend 1) confirmation of all reactive rapid HIV test results with either Western blot (WB) or immunofluorescent assay (IFA), even if an enzyme immunoassay (EIA) screening test is negative, and 2) follow-up testing for persons with negative or indeterminate confirmatory test results, with a blood specimen collected 4 weeks after the initial reactive rapid test result.
The evolution from technically demanding cell culture for C trachomatis to enzyme immunoassay or direct immunofluorescent assay was a big step in public health for the detection of this major sexually transmitted pathogen.
The immunofluorescent assay, the reference serologic method for diagnosis of infection with Rickettsia spp.