This product has only the Anti-Ro/SS-A precipitin band when tested using double immunodiffusion against primate spleen extract or calf spleen extract. The titer obtained will vary with the test system; however, undiluted antibody shows a strong Anti-Ro/SS-A precipitin band.
The specificity is verified by a precipitin line of identity with the CDC-AF reference serum. This product shows no reactivity at a dilution of 1:100 when tested against purified Sm, nRNP, La/SS-B, Scl-70, Jo-1, Mitochondrial, or Ribosomal P antigens in an ELISA system designed to detect IgG antibody. These sera are powerfully positive in an AntiRo/SS-A ELISA system.