Table 4

Human autoantigens with which serum anti-B19 IgG cross reacts

Human autoantigenB19 protein and antigenic region (amino acid numbers)Disease relevanceReference
Collagen II*VP2: 57–80Rheumatoid arthritis (RA)225
Keratin*VP2: 57–80Systemic lupus erythematosus (SLE)225
ssDNA*VP2: 57–80RA, SLE, myositis, hepatitis225
Cardiolipin*VP2: 57–80Antiphospholipid syndrome, SLE225
Angiotensin II type 1 receptor†VP2: 419–425Pre-eclampsia, kidney transplant rejection226
Myelin basic protein‡Not studiedMultiple sclerosis227
Platelet membrane glycoprotein IIb/IIIa§NS1: 70–79Autoimmune thrombocytopenic purpura228
  • *Anti-B19 IgG purified on a column to a single specificity using B19 peptide, FSPAASSCHNASGKEAKVCTISPI, cross-reacted with collagen II, keratin, ssDNA and cardiolipin.

  • †Human IgG monoclonal antibody reacted with AT1 receptor, which could be blocked by AT1 receptor blocker and by the epitope amino acid sequence.

  • ‡Myelin basic protein decreased binding of anti-B19 IgG to B19 antigen in a dose-dependent manner, suggesting a role for anti-B19 IgG in a subset of clinical patients with multiple sclerosis.

  • §This B19 NS1 peptide was shown to exhibit ∼5% inhibition of the platelet membrane glycoprotein autoantibodies of adults with chronic autoimmune thrombocytopenic purpura.