Depending on the activity score of RA, SAA1 isoforms (mainly of SAA1α and SAA1β subtypes) were found to be differentially present in plasma revealing their dual role during the development of RA.
His mother was also a carrier of the SAA1.3 allele, which is not only a univariate predictor of survival but also a risk factor for the association of AA amyloidosis with rheumatoid arthritis in Japanese patients, and the SAA1-13T allele in the 13T/C polymorphism on the 5'-flanking region of the SAA1 gene.
In this study, we investigated the role of serum amyloid A protein (SAA) in the production of interleukin-6 (IL-6) using rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS).
The genotypes of the -13T/C SNP in the 5'-flanking region of the SAA1 gene and the two SNPs within exon 3 of SAA1 (2995C/T and 3010C/T polymorphisms) were determined in 88 Greek patients with RA, 14 patients with familial Mediterranean fever (FMF) and 110 healthy controls.
Levels of CysC and SAA and antibodies against these proteins were assessed in the paired blood and synovial fluid (SF) samples of 90 patients with rheumatoid arthritis (RA).
In this study, the six polymorphisms associated with rheumatoid arthritis (RA), N-acetyltransferase2 (NAT2) gene polymorphisms T341C, G590A, and G857A, methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms C677T and A1298C, and serum amyloid A1 (SAA1) gene promoter polymorphism C-13T were simultaneously detected by the electrochemical DNA chip and the loop-mediated isothermal amplification (LAMP) method, which is a novel technique for DNA amplification.
A-SAA messenger RNA (mRNA) and FPRL1 mRNA were present in FLS, macrophages, and endothelial cells isolated from the synovial tissue of patients with RA and other categories of inflammatory arthritis.
A novel single-nucleotide polymorphism at the 5'-flanking region of SAA1 associated with risk of type AA amyloidosis secondary to rheumatoid arthritis.
The frequencies of the gamma/gamma genotype and gamma alleles at the SAA1 locus were significantly higher in the amyloidosis population than in the early RA population (34.9% versus 7.8%, and 58.1% versus 33.8%, chi2 test P=0.0001).
The local synthesis of A-SAA may contribute, at least in part, to the concentration of A-SAA protein in SF and may contribute to the altered molecular and cellular physiology in RA joints.
It has recently been reported that in the Japanese population, in whom the SAA1 gamma allele occurs with a frequency of 37%, possession of, and especially, homozygosity for this allele is a significant risk factor for AA amyloidosis in adult patients with rheumatoid arthritis (RA).
Serum amyloid A protein (SAA) is a precursor for a major component of amyloid fibrils, which, upon deposition, cause secondary amyloidosis in diseases such as rheumatoid arthritis.