Indirect immunofluorescence assay

Indirect immunofluorescence assay (IFA) 3-6 weeks Plasma Simple to perform, but requires expertise to interpret results... 

Indirect immunofluorescence assay (IFA) A laboratory test used to detect antibodies in serum or other body fluid. The specific antibodies are labeled with a compound that will make them glow a fluorescent green color when observed microscopically under ultraviolet light. 

Positive enzyme-linked immunosorbent assays are repeated in duplicate and if one or both tests are reactive, a confirmatory test is performed for final diagnosis. Western blot assay is the most commonly used confirmatory test, although an indirect immunofluorescence assay is available. 

The causative agent in Lyme disease is a spirochetal bacterium (Borrelia burgdorferi) that is transmitted directly through the bite of a deer tick. Optic neittopathy can occur due to Lyme disease and manifests as papillitis, retrobulbar neuropathy, or ischemic optic neiu-opathy. Serologic testing may help to identify Lyme infection by use of indirect immunofluorescent assay and enzyme-linked immunosorbent assay.The treatment of Lyme disease includes oral or intravenous peniciUin, doxycycUne, erythromycin, or ceftriaxone. 

Take small alicluots of cells to prepare cell smears on the slide for detection of viral antigens. Air-dry the cells, fix the cells in cold acetone for 10 min, air-dry, and then perform indirect immunofluorescent assay (see Appendix 1). 

Leiby, D.A. et al. Serologic Testing for Trypanosoma cruzi Comparison of radioimmunoprecipitation assay with commercially available indirect immunofluorescence assay. Indirect hemagglutination assay, and enzyme-Linked immunosorbent assay kits. J Clin Microbiol 2000 38 639-42. 

The methods outlined below include protocols for direct and indirect immunofluorescence staining, that can be adapted easily for the cell type of interest as indicated in the relevant notes. The principal approaches to flow cytometric analysis, standardization and calibration are then given, followed by two more detailed protocols illustrating quantitation using direct immunofluorescence, and a competitive binding assay, which demonstrates the application of linear amplification of fluorescence. 

Haas GG Jr, D Cruz OJ, DeBault LE. Comparison of the indirect immunobead, radiolabeled, and immunofluorescence assays for immunoglobulin G serum antibodies to human sperm. Fertil Steril 1991 55 377-88. 

The acquired immune deficiency syndrome (AIDS) marks another challenge in immune research. In Austria, an indirect AIDS-immunofluorescence assay has been developed by Waldheim Pharmaceutical Co. It has been approved by the US Food and Drug Administration since 1992 and is mainly recommended as a confirmatory test. 

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