Absolute Quantitation of Isoforms of Post-translationally Modified Proteins in Transgenic Organism

Aim and Objective: Lupus nephritis (LN) is one of the major complications of systemic lupus erythematosus (SLE). The specific mechanisms of pathogenesis, aggravation, and remission processes in LN have not been clarified but is of great need in the clinic. Using isobaric tags for relative and absolute quantitation (iTRAQ) technology to screen the functional proteins of LN in mice. Especially under intervention factors of lipopolysaccharide (LPS) and dexamethasone. Methods: Mrl-lps mice were intervened with LPS, dexamethasone, and normal saline (NS) using intraperitoneal injection, and c57 mice intervened with NS as control. The anti-ANA antibody enzyme-linked immunosorbent assay (ELISA) was used to verify disease severity. Kidney tissue is collected and processed for iTRAQ to screen out functional proteins closely related to the onset and development of LN. Western blot method and rt-PCR (real-time Polymerase Chain Reaction) were used for verification. Results: We identified 136 proteins that marked quantitative information. Among them, Hp, Igkv8-27, Itgb2, Got2, and Pcx proteins showed significant abnormal manifestations. Conclusion: Using iTRAQ methods, the functional proteins Hp, Igkv8-27, Itgb2, Got2, and Pcx were screened out for a close relationship with the pathogenesis and development of LN, which is worth further study.

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Discovering Therapeutic Protein Targets for Bladder Cancer Using Proteomic Data Analysis

Current Molecular Pharmacology ◽

10.2174/1874467212666191016124935 ◽

2020 ◽

Vol 13 (2) ◽

pp. 150-172 ◽

Cited By ~ 1

Author(s):

Samira Bahrami ◽

Bahram Kazemi ◽

Hakimeh Zali ◽

Peter C. Black ◽

Abbas Basiri ◽

...

Keyword(s):

Bladder Cancer ◽

Gene Ontology ◽

Monoclonal Antibodies ◽

Membrane Proteins ◽

Growth Factor Receptor ◽

Subcellular Location ◽

Cancer Tissue ◽

Heat Shock Protein 60 ◽

Absolute Quantitation ◽

Muscle Invasive

Background: Bladder cancer accounts for almost 54% of urinary system cancer and is the second most frequent cause of death in genitourinary malignancies after prostate cancer. About 70% of bladder tumors are non-muscle-invasive, and the rest are muscle-invasive. Recurrence of the tumor is the common feature of bladder cancer. Chemotherapy is a conventional treatment for MIBC, but it cannot improve the survival rate of these patients sufficiently. Therefore, researchers must develop new therapies. Antibody-based therapy is one of the most important strategies for the treatment of solid tumors. Selecting a suitable target is the most critical step for this strategy. Objective: The aim of this study is to detect therapeutic cell surface antigen targets in bladder cancer using data obtained by proteomic studies. Methods: Isobaric tag for relative and absolute quantitation (iTRAQ) analysis had identified 131 overexpressed proteins in baldder cancer tissue and reverse-phase proteomic array (RPPA) analysis had been done for 343 tumor tissues and 208 antibodies. All identified proteins from two studies (131+208 proteins) were collected and duplicates were removed (331 unique proteins). Gene ontology study was performed using gene ontology (GO) and protein analysis through evolutionary relationships (PANTHER) databases. The Human Protein Atlas database was used to search the protein class and subcellular location of membrane proteins obtained from the PANTHER analysis. Results: Membrane proteins that could be suitable therapeutic targets for bladder cancer were selected. These included: Epidermal growth factor receptor (EGFR), Her2, Kinase insert domain receptor (KDR), Heat shock protein 60 (HSP60), HSP90, Transferrin receptor (TFRC), Activin A Receptor Like Type 1 (ACVRL1), and cadherin 2 (CDH2). Monoclonal antibodies against these proteins or their inhibitors were used for the treatment of different cancers in preclinical and clinical trials. Conclusion: These monoclonal antibodies and inhibitor molecules and also their combination can be used for the treatment of bladder cancer.

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Conformational Studies on Modified Proteins and Peptides

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)62826-1 ◽

1970 ◽

Vol 245 (19) ◽

pp. 5122-5128

Author(s):

M.Z. Atassi ◽

R.P. Singhal

Keyword(s):

Conformational Studies ◽

Modified Proteins ◽

Proteins And Peptides

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The Alterations in Methylene Blue/Light-Treated Frozen Plasma Proteins Revealed by Proteomics

Transfusion Medicine and Hemotherapy ◽

10.1159/000515119 ◽

2021 ◽

pp. 1-8

Author(s):

Tiange Wu ◽

Xiaoning Wang ◽

Kai Ren ◽

Xiaochen Huang ◽

Jiankai Liu

Keyword(s):

Mass Spectrometry ◽

Methylene Blue ◽

Western Blot ◽

Blue Light ◽

Differentially Expressed ◽

Enzyme Linked Immunosorbent Assay ◽

Differentially Expressed Protein ◽

Significant Difference ◽

Modified Proteins ◽

Frozen Plasma

Introduction: The aim of this study was to investigate the modified proteins in methylene blue/light-treated frozen plasma (MB-FP) compared with fresh frozen plasma (FFP) in order to gain a better application of MB/light-treated plasma in clinic transfusion. Methods: MB-FP and FFP were collected from Changchun central blood station, and a trichloroacetic acid/acetone precipitation method was used to remove albumin for the enrichment of lower abundance proteins. The plasma protein in MB-FP and FFP were separated using two-dimensional gel electrophoresis (2-DE) and the differentially expressed protein spots were analyzed using mass spectrometry. Finally, the differentially expressed proteins were tested using Western blot and enzyme-linked immunosorbent assay (ELISA). Results: Approximately 14 differentially expressed protein spots were detected in the MB-FP, and FFP was chosen as the control. After 2-DE comparison analysis and mass spectrometry, 8 significantly differentially expressed protein spots were identified, corresponding to 6 different proteins, including complement C1r subcomponent (C1R), inter-alpha-trypsin inhibitor heavy chain H4 (ITI-H4), keratin, type II cytoskeletal 1 (KRT1), hemopexin (HPX), fibrinogen gamma chain (FGG), and transthyretin (TTR). Western blot showed no significant difference in the expression level of KRT1 between MB-FP and FFP (p > 0.05). Both Western blot and ELISA indicated that the level of HPX was significantly higher in FFP than in MB-FP (p < 0.05). Conclusion: This comparative proteomics study revealed that some significantly modified proteins occur in MB-FP, such as C1R, ITI-H4, KRT1, HPX, FGG, and TTR. Our findings provide more theoretical data for using MB-FP in transfusion medicine. However, the relevance of the data for the transfusion of methylene blue/light-treated plasma remains unclear. The exact modification of these proteins and the effects of these modified proteins on their functions and their effects in clinical plasma infusion need to be further studied.

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