AC-7 - Few Nuclear Dots

Countable discrete speckles (1 to 6 nuclear dots/cell in most cells). These are known as Cajal bodies or coiled bodies. e.g. anti-p80-coilin.
Associação Antigênica
p80-coilin, SMN
Doença Associada
SjS, SLE, SSc, PM, asymptomatic individuals.
Relevância Clínica (Primeiro Nível)
The AC-7 pattern has low positive predictive value for any disease.
Antigens primarily localized in the dots include p80-coilin and SMN complex; specific immunoassays for these autoantibodies are currently not commercially available.
Relevância Clínica (Segundo Nível)
Anti-p80-coilin antibodies may rarely occur in SLE, (localized linear) SSc, and SjS.
Isolated (without anti-snRNPs) anti-SMN antibodies are reported in patients with AIM or SSc-AIM overlap syndrome.
The specificity of antibodies to p80-coilin and the SMN complex can be confirmed by Western blot, solid phase immunoassays using recombinant proteins and immunoprecipitation.
Most reports describe autoantibodies directly binding to specific antigens (i.e. antigen-specific immunoassays) and do not actually show clear correlations with the AC-7 pattern as such; specific immunoassays for these autoantibodies are currently not commercially available.
Amlani A, Hazlewood GS, Hamilton L, et al. Autoantibodies to the survival of motor neuron complex in a patient with necrotizing autoimmune myopathy. Rheumatology 2018;57:199-200.

Andrade LE, Chan EK, Raska I, et al. Human autoantibody to a novel protein of the nuclear coiled body: immunological characterization and cDNA cloning of p80-coilin. J Exp Med 1991;173:1407-19.

Fujimoto M, Kikuchi K, Tamaki T, et al. Distribution of anti-p80-coilin autoantibody in collagen diseases and various skin diseases. Br J Dermatol 1997;137:916–20.

Onouchi H, Muro Y, Tomita Y. Clinical features and IgG subclass distribution of anti-p80 coilin antibodies. J Autoimmun 1999;13:225-32.

Satoh M, Chan JY, Ross SJ, et al. Autoantibodies to survival of motor neuron complex in patients with polymyositis: immunoprecipitation of D, E, F, and G proteins without other components of small nuclear ribonucleoproteins. Arthritis Rheum 2011;63:1972–8.