TNF and rheumatoid arthritis: In the other five patients (three with previous positive anti-Jo-1 antibodies, one with anti-PL-7, and another one with anti PL-12) the emergence of PM/DM and the aggravation of the clinical picture previously compatible with RA associated with interstitial lung disease was compatible with a full development of an antisynthetase syndrome, probably unmasked by the use of anti-TNF-α agents.