Native - Calf Thymus
Anti-ribosomal P antibodies are considered to be specific for systemic lupus erythematosus (SLE), and their presence frequently correlates with disease activity, in particular psychotic depression, hepatitis, and nephritis. Although anti-ribosomal P antibodies have been reported to occur in patients with systemic sclerosis, this would appear to be rare and normally indicates an overlap with SLE.
The P proteins are three of approximately 80 proteins that make up the largest cytoplasmic ribonucleoprotein, the ribosome. Since ribosomes are assembled in the nucleoli, high titre anti-ribosomal P sera will show nucleolar as well as cytoplasmic immunofluorescent staining. The exact functions of the individual P proteins are not fully understood however studies suggest that they collectively comprise part of a functional GTPase domain necessary for the binding of factor-GTP complexes. This interaction results in catalysis of the appropriate step of the protein synthesis cycle (initiation, elongation or release).
The C-terminal 17 amino acids of all three P proteins are virtually identical and are highly conserved between species. Although the major autoantibody epitope on all three proteins is believed to be located within the C-terminal 22 amino acids, there is recent evidence that other individual P protein-specific epitopes occur.
The ribosomal P0, P1 and P2 proteins are all present in AROTEC’s ribosomal P antigen. The antigen typically exhibits a 260/280 nm absorbance ratio of >1.5, suggesting that a significant rRNA component is present. The sequences of the bovine P0 and P2 proteins have been determined, and found to be very homologous (>99%) to their human equivalents. In particular the C-terminal 22 amino acids of both species were found to be identical.
Ribosomal P datasheet
Systemic Lupus erythematosus
Please log in to view certificates of analysis for this item