Ribonucleoprotein antibodies (anti-RNP) are antinuclear antibodies (ANA) belonging to the extractable nuclear antigen antibodies (ENA) subset. Anti-RNP antibodies are directed against the U1-ribonucleoprotein of the ribonucleoprotein multienzyme complex.
The presence of specific antibodies to U1-RNP can help confirm a suspected diagnosis of an autoimmune disease: Anti-RNP tests are positive in 95-100% of sera from patients with mixed connective tissue disease (MCTD). However, some patients with systemic lupus erythematosus (SLE) and systemic sclerosis may also test positive for anti-RNP.
Antibodies to RNP-70, the 70 kDa protein of the U1-RNP complex show the highest diagnostic sensitivity for MCTD, their absence completely rules out this disease. Up to 32% of patients with SLE and up to 10% of patients with systemic scleroderma present with detectable anti-RNP-70 titers.
Tests offered by ORGENTEC Diagnostika
Nucleo-9-Line (ORG 711)