Stevens Immunology-Serology Practice Test

In ANA testing by indirect immunofluorescence, the pattern of nuclear staining helps identify the likely antibody. A ring or rim of fluorescence around the nucleus is the hallmark of antibodies against double-stranded DNA. This peripheral pattern occurs because anti-dsDNA binds along the outer edge of the nucleus in fixed cells, producing a circular rim of staining. Clinically, anti-dsDNA is highly associated with systemic lupus erythematosus and often correlates with disease activity, especially lupus nephritis. Other antibodies tend to produce different patterns—centromere antibodies show discrete centromeric speckles, Sm antibodies often give a speckled pattern, and SSA/Ro can yield speckled or nucleolar patterns—so the peripheral nuclear rim is most characteristic of anti-dsDNA.