> See also: > - [[Immunofluorescence]] # Antinuclear Antibody Tests Antinuclear antibodies (ANAs) are indicative of [[Autoimmunity]], specifically a group known as [[Systemic Autoimmune Rheumatic Diseases (SARDs)|SARDS]]. Testing for the presence of ANAs is useful when screening for these diseases Antinuclear antibody tests are a qualitative method for detecting ANAs in human serum. It uses [[Immunofluorescence]] **Human epithelioid (Hep-2) cells** are the *substrate* which are grown on a slide. *Anti-IgG antibodies* are combined with a fluorescent reagent to create a conjugate antibody that can be detected in an immunofluorescencce test. > [!info] Knowns vs Unknowns > **Unknowns** > - Presence of antinuclear antibodies in patient sample (serum) > > **Knowns** > - ANA antigen substrate (Hep-2 cells) > - Secondary antibody with fluorescent conjugate --- **Procedure** Two places you must wash: 1) First, after serum sample is added (ex. homogeneous) 2) Second, after the fluorescent reagent has been added ### Limitations ### Immunofluorescence Analysis ![[Pasted image 20230303102021.png|600]] Sjorgen's Syndrome Nucleolar Pattern -> Scleroderma (SSc) Speckled Pattern Homogeneous Pattern