The MIF Detection And Analysis Of Single-Nucleotide Polymorphism Of MIF Gene In Rheumatoid Arthritis

PartⅠThe clinical significance of MIF detection in rheumatoid arthritisobject: To study the clinical significance of MIF detection in serum and synovium in rheumatoid arthritis.methods: (1)The serum MIF level was assayed in 40 cases of rheumatoid arthritis patients and 20 healthy volunteers by ELISA. According to disease activety score 28(DAS28), 40 cases of rheumatoid arthritis were divided into active group(n=25) and inactive group(n=15). (2)The MIF in synovium tissues was detected by immunohistochemistry in 13 cases of rheumatoid arthritis, 7 cases of osteoarthritis and 4 healthy subjects. The correlation between the MIF expression level and the synovitis was analyzed.Results:(1)The serum MIF level in rheumatoid arthritis group(13.37±7.49ng/ml)was obviously higher than the control group(4.57±1.91ng/ml)(p<0.01). Within rheumatoid arthritis group, the MIF level in active group (15.94±7.67ng/ml)was obviously higher than inactive group(9.07±4.89ng/ml)(p<0.01). The MIF level was correlated to disease activity score 28(DAS28), erythrosedimantation (SR), C-reactive protein(CRP), morning stiffness, swollen counts (SW28) , tender joint counts(T28) and rheumatoid factor(RF), but it wasn't correlated to the disease duration and the destrction of joint on X-rays. (2)The MIF postive rate in rheumatoid arthritis synovium(60%)was obviously higher than osteoarthritis(5.3%)and normal synovium(0.5%)(p<0.01). The MIF postive rate was correlated obviously with the synovitis(r=0.872). The MIF localized in inflammatory cells, vascular endothelial cells and fibroblast-like synovio- cytes(FLS).Conclutions: (1)The MIF played an important role in the pathogenesis of RA. (2) The MIF expressed in synovium was associated with the severity of synovitis. The MIF might be an indictor for the active rheumatiod arthritis.PartⅡThe Analysis of the single-nucleotide polymorphism of MIF gene in rheumatoid arthritisobject: To analyze the single-nucleotide polymorphism (SNP) of MIF gene in rheumatoid arthritis.methods: The genomic DNA in peripheral blood from 45 cases of rheumatiod arthritis patients and 30 health subjects were extracted. The 129bp nucleotides containing MIF-173G/C gene were amplified by PCR. The fragments were denatured, and then analyzed by acrylamide gel electrophoresis. The DNA sequencing was also used for the single nucleotide polymorphism.Results: In 43 cases of rheumatoid arthritis patients, 28 cases(65.1%) possess a MIF-173G/G allele, 10 cases(23.2%) possess a MIF-173G/C allele,5 cases(11.6%) possess a MIF-173C/C allele. But in health control group, 19 individuals(66.3%) possess a MIF-173G/G allele, 8 individuals (26.7%) possess a MIF-173G/C allele, 3 individuals(10%) possess a MIF-173C/C allele. The genotype frequencies in two groups were not significant difference (P>0.05) .Conclutions: MIF-173SNP polymorphism was founded in Han populations, and was not related to the susceptibility to rheumatiod arthritis.