The Detection And Significance Of HLA-B27 Subtype And PPM1A In Patients With Ankylosing Spondylitis

Objective: The aim of this study were to investigate distribution characteristics of HLA-B27 subtypes in patients with ankylosing spondylitis(AS)in Fuzhou area by using fluorescence quantitative PCR method;and to detecte the expression of serum PPMIA in AS patients and evaluate its clinical application value for AS diagnosis..Methods: Using fluorescence quantitative PCR and flow cytometry the expression of HLA-B27 gene in AS patients was detected.The level of PPM1 A in AS patients and control group(including RA,SLE patients and the healthy adult group)was evaluated by ELISA method.The results were statistically analyzed by SPSS18.0.Results: 1.Among 202 cases of AS,HLA-B27 was positive in 196(97.03%)by fluorescence quantitative PCR method,and in 194(96.03%)by flow cytometry method.The positive rate of the two methods was not significantly different(P=0.5).2..The main subtype of HLA-B27 gene in patients with AS was 2704(88.61%)?2705(5.45%)?2710(1.98%)2708/11/12(0.99%)and the negenative 2.97%.3.The ELISA method for the detection of levels of PPM1 A in AS,RF,SLE patients and NC.The results showed that the serum of PPM1 A in AS patients was 85.75(45.74-417.92)pg/ml,significantly higher than the level of 44.07(18.80-264.14)pg/mlin RF group(P=0.0209),,20.86(16.29-26.29)pg / ml SLE group(P < 0.0001),and 19.54(15.11-24.81)pg / ml in healthy control group(P < 0.0001)4.There was a significant correlation between serum PPM1 A level and ESR or CRP levels in group AS.The levels of ESR and CRP in PPM1A(+)AS group were significantly higher than those in group PPM1A(-)(P<0.05),and the age of PPM1A(+)AS group was significantly lower than that of PPM1A(-)AS group(P<0.05).5.The ROC curve was used to evaluate the diagnostic efficacy of PPM1 A to AS,and the results showed that when the cut-off value was set as 32.50pg/ml,the sensitivity was 88.8%,and the specificity was 100%.Conclusion:1.The fluorescent quantitative PCR and flow cytometry assay in the detection of HLA-B27 in AS patients does not have statistical significance,but fluorescence quantitative PCR method can detect specific HLA-B27 subtypes and flow cytometry method can identify the double positive results.2.AS patients in Fuzhou region HLA-B27 positive rate was 97.03%.The main subtype were 2704(88.61%)and 2705(5.45%).Other subtypes were rare.3.The serum of PPM1 A in AS patients was significantly higher than that of RF patients,SLE patients and healthy controls.Therefore,PPM1 A has important diagnostic value for AS,and can be used as one of the specific serum markers for AS.