Objective: To examine a well characterized group of patients with systemic lupus erythematosus (SLE) for anti-calreticulin.
Methods: The sera of 77 patients with SLE were studied by immunodiffusion, solid phase immunoassay, and immunoblot for antibodies against ribonucleoprotein (RNP) autoantigens and calreticulin.
Results: Thirty-five had anti-calreticulin and 40 had anti-60 kDa Ro. There was no association of anti-60 kDa Ro and anti-calreticulin. However, among anti-60 kDa Ro positive sera that also contained either anti-La or anti-RNP, none of 18 had anti-calreticulin. All the remaining sera with anti-60 kDa Ro had anti-calreticulin and anti-52 kDa Ro.
Conclusion: Anti-60 kDa Ro patients with SLE can be divided into those with anti-60 kDa Ro and either anti-La or anti-RNP or those with anti-60 kDa Ro, anti-52 kDa Ro, and anti-calreticulin.