The PM/Scl is the human exosome which is an large intracellular protein complex. It plays a role in Nonsense Mediated Decay (NMD) which is a surveillance pathway that eliminates mRNA transcripts that contain premature stop codons.

The primary target antigens of PM-Scl antibodies are the proteins PM-Scl 100 (100 kDa) and PM-Scl 75 (75 kDa). PM-Scl 100 is detected virtually by 100 % of PM-Scl antibodies, and PM-Scl 75 by 50-60 %. It was shown in the literature that PM-Scl 75 antibodies can be found in the absence of PM-Scl 100 antibodies but the occurrence of such cases seems to be very rare.

PM-Scl antibodies are found almost exclusively in patients with Polymyositis/Scleroderma overlap syndrome (20-25 %), PM/DM (8-12 %) and Scleroderma (1-16 %). Interestingly PM-Scl is a reliable marker for Juvenile Scleromyositis (overlap syndrome, mild Scleroderma and Myositis in children) which appears to be the most common Scleroderma like disease of childhood. The clinical course is relatively benign compared to that of Juvenile Dermatomyositis or Scleroderma.


Antigen used by D-tek

Recombinant human, expressed in Baculovirus-infected Sf9 cells (for more information on our antigens click here)