ABSTRACT
Objective To scan protein expression profile of immune complexes (ICs) derived from the synovial tissue of the patients with rheumatoid arthritis (RA) based on liquid chromatography-tandem mass spectrometry (LC-MS).Methods The samples of synovial fluid were obtained from knee joints of the patients with RA and osteoarthritis (OA) used as control during therapeutic arthrocentesis in knee jiont at the Department of Orthopedics of Jinling Hospital,School of Medicine,Nanjing University.The protein expression profile of ICs was identified by enrichment strategy based on immunoprecipitation and LC-MS analysis.The value of fraction of total (FOT) was used to estimate protein abundance and screen the up-and down-regulated proteins.The function enrichment,interaction network and signal pathway of differential proteins were analyzed using softwares David and String.Results A total of 511 and 526 protein spots in ICs of RA and OA patients were identified respectively.Among them,170 proteins existed only in RA group.45 and 85 proteins in RA group were statistically up-and down-expressed compared with controls.Conclusion HSP90AA1,HSP70,HLAG,Thioredoxin,Annexin A2 and vitronectin may be involved in the pathogenesis of RA through different paths and possible to become promising diagnostic indicators or new therapeutic targets for RA.
ABSTRACT
Objective Rheumatoid arthritis (RA) is a typical type Ⅲ hypersensitivity with a large number of immune complexes (IC) and complement deposits in the synovial tissue , but its specific pathogenesis is not yet clear.This article was to explore the expression of the antigenic profile of serum ICs in RA.Methods ICs were isolated from the serum of 55 patients with RA (41 cases of anti-CCP antibody [+] and 14 cases of anti-CCP antibody [-]), 41 with systemic lupus erythematosus (SLE), and another 41 healthy controls by polyethylene glycol (PEG) precipitation, separated by immunoprecipitation, digested with trypsin in gel, and then subjected to mass spectrometry for identification.The levels of total proteins were compared among different groups using Vennny 2.1.0.The protein expression was considered to be up-regulated when the total protein level of the RA group was >2 times and down-regulated when it was <0.5 times that of the control.Further functional analysis was performed on the differential proteins in RA using the STRING software.Results Totally, 277 proteins were identified in the serum ICs of the RA patients, including 162 in the anti-CCP (+) and 248 in the anti-CCP (-) RA group.Compared with the SLE and healthy control groups, only 129 proteins were found in the RA patients, including 38 in the anti-CCP (+), 109 in the anti-CCP (-) RA group, and 18 in both the two groups.Among the proteins identified in the RA patients and healthy controls, 2 and 11 were up-regulated while 17 and 21 down-regulated in the anti-CCP (+) and anti-CCP (-) RA group, respectively.Conclusion More differentially expressed proteins were identified in the anti-CCP (-) than in the anti-CCP (+) RA patients.The identification of differentially expressed proteins provides a new idea and direction for the investigation of the pathogenesis and new biomarkers of RA.
ABSTRACT
Objective The inhibitor of differentiation 3 (Id3) is an important transcriptional regulation factor, which participates in tumorigenesis, cell proliferation, and cell apoptosis.β-catenin, as a central molecule of the Wnt signaling pathway, is critical for tumor development.This study aimed to evaluate the expressions of these two molecules and the regulatory effect of Id3 on β-catenin in different tumor cells.Methods Total RNA was extracted using the Trizol Reagent.The relative mRNA expression levels of Id3 and β-catenin in tumor cells were detected by quantitative real-timePCR(qRT-PCR).The recombinant eukaryotic expression vector pEGFP/Id3 with the human Id3 gene was transfected into A549, A549/ DDP and SW-480 cells using the non-liposome-mediated method.The protein expressions of Id3 and β-catenin were determined by Western blot.Results The expression of Id3 was significantly lower in the colorectal cancer cell lines SW-480 and HT-29 than in A549 and other tumor cells (P0.05).Western blot showed the same results.Conclusion The expression levels of Id3 and β-catenin vary in different tumor cell lines.Anabnormally high level of β-catenin is an important risk factor for colorectal cancer, and the down-regulatedexpression of β-catenin after eogenous transfection of Id3 may provide some new ideas for target gene therapies of colorectal cancer.