Autoantibodies in patients with primary pulmonary hypertension: association with anti-Ku

Am J Med. 1992 Sep;93(3):307-12. doi: 10.1016/0002-9343(92)90238-7.


Purpose: Patients with primary pulmonary hypertension (PPH) frequently have Raynaud's phenomenon, serum antinuclear antibodies (ANAs), and/or pulmonary vascular lesions similar to those seen in certain connective tissue diseases, especially scleroderma. A number of relatively disease-specific autoantibodies have been described in connective tissue diseases but have not been studied in patients with PPH. Therefore, sera from PPH patients were studied for a variety of autoantibodies, seeking a possible link between this pulmonary disorder and connective tissue diseases.

Patients and methods: Sera from 31 patients with PPH and 24 with secondary pulmonary hypertension (SPH) were studied for the following autoantibodies: anti-centromere (indirect immunofluorescence of Hep-2 cells), anti-CENP-B by immunoblotting and enzyme immunoassay (EIA) using cloned CENP-B fusion protein, anti-topoisomerase I (Scl-70), anti-Ku using immunoblotting of affinity purified antigens, anti-cardiolipin using EIA, and anti-Ro (SS-A), La (SS-B), Sm, nRNP, Jo-1, PM-Scl, and Mi-2 by counter-current immunoelectrophoresis.

Results: Anti-Ku antibodies were found in 23% of patients with PPH, 4% with SPH, and none of 24 normal controls (PPH versus SPH, p = 0.06: PPH versus controls, p = 0.01). Antibodies to CENP-B were found in one patient each with PPH and SPH, anti-topoisomerase I in one with SPH, and anti-Ro (SS-A) and La (SS-B) in one with PPH. Overall, 12 patients (39%) with PPH had Raynaud's phenomenon or positive ANA results, with 9 (29%) having more specific autoantibodies associated with connective tissue diseases.

Conclusions: These results further suggest a link between at least a subgroup of patients with PPH and autoimmune connective tissue diseases, with anti-Ku antibodies being a possible new serologic marker.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Antigens, Nuclear*
  • Autoantibodies / blood*
  • Autoantigens / immunology*
  • Biomarkers / blood
  • Connective Tissue Diseases / immunology
  • DNA Helicases*
  • DNA-Binding Proteins / immunology*
  • Female
  • Humans
  • Hypertension, Pulmonary / immunology*
  • Immunoblotting
  • Ku Autoantigen
  • Male
  • Middle Aged
  • Nuclear Proteins / immunology*


  • Antigens, Nuclear
  • Autoantibodies
  • Autoantigens
  • Biomarkers
  • DNA-Binding Proteins
  • Nuclear Proteins
  • DNA Helicases
  • XRCC5 protein, human
  • Xrcc6 protein, human
  • Ku Autoantigen