Plasma TNF-α Elevation in Biologic Naive Rheumatoid Arthritis PatientsBelonging to a Population with New Mutations in TLR4 and CYP51A1 geneswithout Association with Disease-Related Antibodies Levels

Document Type : Original Article

Authors
Ezatollah Mosavi 1
Mojgan Bandehpour 2 , 3
Amrollah Mostafazadeh 4
Behnaz YousefGhahari 5
Fateme Majidi 6
Hakimeh Zali 7
Bahram Kazemi 3
1 Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
2 Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
3 Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
4 Department of Immunology, School of Medicine, Babol University of Medical Sciences, Babol, Iran.
5 Department of Internal Medicine, School of Medicine, Babol University of Medical Sciences, Babol, Iran.
6 Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, Tehran, Iran.
7 Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
10.22088/IJMCM.BUMS.13.2.171
Abstract
In a system biology-based study, we previously reported that IL-6 and IL6R -specific m-RNA levels were elevated in
leukocytes of patients with Rheumatoid arthritis (RA). Here, the association of toll-like receptor4 (TLR4) rs 141534085
and cytochrome P450 family 51 subfamily A member 1(CYP51A1) rs6 with tumor necrosis factor-α (TNF- α),
rheumatoid factor (RF)- and Anti- cyclic citrullinated peptide (anti-CCP) antibody -positivity was investigated in almost
the same subjects. Forty-six patients and 48 normal subjects were recruited in this study. The blood leucocytes TLR4 rs
141534085 and CYP51A1 rs6 -comprising DNA sequences were amplified by using tetra-primer amplification refractory
mutation system polymerase chain reaction (T-ARMS-PCR) technique and the PCR products were checked by Sanger
DNA sequencing method. ELISA method was used to determine plasma levels of TNF- α, anti-CCP antibody and RF
positivity of plasma was evaluated through a latex agglutination test. The TNF- α level was significantly higher in the
patient group than control subjects (p= 0.001). Moreover, we were not able to find any correlation between TNF-α levels
and RF as well as anti-CCP antibodies when we used the K2/ Fisher's exact test and Pearson test respectively. Our DNA
sequencing data revealed the following new mutations in TLR4 rs141534085 comprising regions: A>T in position 1050,
T>A in position 1052, and C>A in position 1054; and for CYP51A1 rs6 encompassing region, the new mutations were;
G>A in position 21680, the T nucleotide was inserted in position 21762 and the G nucleotide was inserted in position
21763, G>T in position 21764. The data of this study showed that both TLR4 rs141534085 and CYP51A1 rs6 related
DNA regions should be considered as hotspot areas in RA pathogenicity. Moreover, these data indicated that, TNF- α
did not alter the production of anti-CCP and RF pathogenic antibodies in patients with long-term RA.
Keywords
Rheumatoid arthritis, TLR4, CYP51A1, TNF-α, mutation