SELDI-TOF-MS Screening Specific Proteins In Serum Of Patients With Ankylosing Spondylitis

Part I:SELDI-TOF-MS screening specific proteins in serum of patients with ankylosing spondylitisObjective:To study the specific proteins by surface-enhanced laser desorption ionization/time of flight mass spectrometry (SELDI-TOF-MS) in serum of patients with ankylosing spondylitis (AS).Methods:The serum samples of 69 AS patients and 12 healthy individuals were detected by SELDI-TOF-MS and weak cation exchange (WCX-2) chip. Then the protein fingerprintings were obtained. To find the specific proteins and to set up the diagnostic models by analyzing protein fingerprintings using biomarker wizard and biomarker pattern software. Further more, 69 AS patients were divided into several types such as the condition of illness was active or not, human leukocyte antigen (HLA)-B27 was positive or negative, with or without hip involvement, whether had ophthalmia and so on, then set up diagnostic models.Results:1. The contents of 27 proteins between AS patients and healthy groups were significantly different. The diagnostic model which make up of 8085, 2640 and 2932 could be used to diagnose AS in early stage. The sensitivity and specificity were 94.23% and 100% respectively.2. The contents of 30 proteins between active and non-active AS patients were significantly different. The diagnostic model which make up of 3677, 3880, 2539, 3159 and 3242 could be used to determine the disease activity of AS. The sensitivity and specificity were 98.11% and 100% respectively.3. The contents of 3 proteins between AS patients whether involved peripheral arthritis or not were significantly different. The diagnostic model which make up of 4700, 8687 and 18538 could be used to predict AS whether involve peripheral arthritis. The sensitivity and specificity were 80.00% and 82.35% respectively.4. The contents of 23 proteins between AS and rheumatoid arthritis (RA) patients were significantly different. The diagnostic model which make up of 10259, 7972, 2048, 2154 and 2954 could be used to distinguish AS and RA. The sensitivity and specificity were 100% and 100% respectively.5. The contents of 7 proteins between AS and osteoarthritis (OA) patients were significantly different. The diagnostic model which make up of 3108, 2890 and 5439 could be used to distinguish AS and OA. The sensitivity and specificity were 95.65% and 100% respectively.Conclusion:The serum protein fingerprinting by SELDI-TOF-MS could identify new biomarkers in AS. The biomarkers may play an important role in pathogenesis of AS. We could diagnose AS in early stage, predict disease progression and determine disease activity by these biomarkers. Part II: The expression of MMP-3 and SAA in serum of patients with ankylosing spondylitisObjective:To detect the expression of matrix metalloproteinase-3 (MMP-3) and serum amyloid protein A (SAA) in serum of patients with ankylosing spondylitis. In addition, to analyze the relationship between MMP-3, SAA and disease activity. And to explain the possible roles they played in pathogenesis of AS.Methods:1. To detect the expression of MMP-3 and SAA in serum of 72 cases of newly diagnosed AS and 20 healthy controls by using enzyme linked immunosorbent assay (ELISA).2. AS patients were divided into in active (54 cases) or non-active stage (18 cases) according to the current activities standards. Besides the patients were divided into gradeâ…¡(20 cases), gradeâ…¢(35 cases) and gradeâ…£(17 cases) according to the X-rays changes of sacroiliac joint.3. Further respectively analyze the relationship among MMP-3, SAA, ankylosing spondylitis disease activity index (BASDAI), ankylosing spondylitis functional index (BASFI), erythrocyte sedimentation rate (ESR), c-reactive protein (CRP) and so on.Results:1. The level of MMP-3 was no statistical difference between AS and healthy group and the level of SAA increased obviously in AS compared with healthy group.2. The level of MMP-3 and SAA increased obviously in active AS compared with non-active and healthy group. MMP-3 and SAA levels were no statistical difference between non-active AS and healthy group.The level of MMP-3 was no statistical significance in different X ray changes of sacroiliac joint. The level of SAA increased obviously in gradeâ…¢compared with gradeâ…¡.3. The level of MMP-3 showed correlation with BASDAI, BASFI, ESR, CRP and SAA. The level of SAA showed correlation with BASDAI, BASFI, patient's global assessment (PGA), spinal inflammation, ankylosing spondylitis metrology index (BASMI), thoracic activity, ESR and CRP.Conclusion:MMP-3 and SAA may play important roles in the pathogenesis of AS. They could be used as potential biomarkers to evaluate disease progression and disease activity.