Development of a quick serum IL-6 measuring system in rheumatoid arthritis.

Objective: Interleukin-6 (IL-6) plays a crucial role in the pathogenesis of rheumatoid arthritis (RA). Both fulfillment of remission criteria and assessment of other methods of evaluation of RA are important for preventing joint damage progression. Measurement of serum IL-6 concentrations has been reported to be useful for monitoring RA disease activity.

An original patient-derived xenograft of prostate cancer with cyst formation.

Background: The high rate of failure of new agents in oncology clinical trials indicates a weak understanding of the complexity of human cancer. Recent understanding of the mechanisms underlying castration resistance in prostate cancer led to the development of new agents targeting the androgen receptor pathway; however, their effectiveness is limited. Hence, there is a need for experimental systems that are able to better reproduce the biological diversity of prostate cancer in preclinical settings.

Plasma biomarker for detection of early stage pancreatic cancer and risk factors for pancreatic malignancy using antibodies for apolipoprotein-AII isoforms.

We recently reported that circulating apolipoprotein AII (apoAII) isoforms apoAII-ATQ/AT (C-terminal truncations of the apoAII homo-dimer) decline significantly in pancreatic cancer and thus might serve as plasma biomarkers for the early detection of this disease. We report here the development of novel enzyme-linked immunosorbent assays (ELISAs) for measurement of apoAII-ATQ/AT and their clinical applicability for early detection of pancreatic cancer. Plasma and serum concentrations of apoAII-ATQ/AT were measured in three independent cohorts, which comprised healthy control subjects and patients with pancreatic cancer and gastroenterologic diseases (n = 1156).

Carbonic anhydrase I as a new plasma biomarker for prostate cancer.

Serum prostate-specific antigen (PSA) levels ranging from 4 to 10 ng/mL is considered a diagnostic gray zone for detecting prostate cancer because biopsies reveal no evidence of cancer in 75% of these subjects. Our goal was to discover a new highly specific biomarker for prostate cancer by analyzing plasma proteins using a proteomic technique. Enriched plasma proteins from 25 prostate cancer patients and 15 healthy controls were analyzed using a label-free quantitative shotgun proteomics platform called 2DICAL (2-dimensional image converted analysis of liquid chromatography and mass spectrometry) and candidate biomarkers were searched.

Serum proteome analysis in patients with rheumatoid arthritis receiving therapy with etanercept, a chimeric tumor necrosis factor-alpha receptor.

Aim: Rheumatoid arthritis (RA) is a chronic inflammatory disorder of the synovium resulting in the destruction of affected joint cartilage and bone structures. Etanercept is a biological agent that blocks the tumor necrosis factor-α (TNF-α)-mediated inflammatory processes in RA patients, and has a regenerative effect on cartilage. In order to identify novel disease-related proteins and candidate biomarkers, we performed proteomic profiling of the serum in patients with RA who were treated with etanercept.

Identification of adipophilin as a potential plasma biomarker for colorectal cancer using label-free quantitative mass spectrometry and protein microarray.

Background: The aim of this study was to identify a new plasma biomarker for use in early detection of colorectal cancer.

Methods: Using the combination of hollow fiber membrane (HFM)-based low-molecular weight protein enrichment and two-dimensional image converted analysis of liquid chromatography and mass spectrometry (2DICAL), we compared the plasma proteome of 22 colorectal cancer patients with those of 21 healthy controls. An identified biomarker candidate was then validated in two larger cohorts [validation-1 (n = 210) and validation-2 (n = 113)] using a high-density reverse-phase protein microarray.

Reduced plasma level of CXC chemokine ligand 7 in patients with pancreatic cancer.

Background: Early detection is essential to improve the outcome of patients with pancreatic cancer. A noninvasive and cost-effective diagnostic test using plasma/serum biomarkers would facilitate the detection of pancreatic cancer at the early stage.

Methods: Using a novel combination of hollow fiber membrane-based low-molecular-weight protein enrichment and LC-MS-based quantitative shotgun proteomics, we compared the plasma proteome between 24 patients with pancreatic cancer and 21 healthy controls (training cohort).

Nanocapsules incorporating IgG Fc-binding domain derived from Staphylococcus aureus protein A for displaying IgGs on immunosensor chips.

To enhance the sensitivities and antigen-binding capacities of immunosensors, oriented immobilization of antibodies on the surface of the sensor chip is critical, but to date, this has not been adequately achieved. We describe a way of adsorbing immunoglobulin (Ig) proteins onto 32-nm bio-nanocapsules (BNCs) through IgG Fc-binding domains derived from Staphylococcus aureus protein A (ZZ-BNC). This arrangement permits approximately 60 molecules of mouse total IgG bind to ZZ-BNC and all the IgG Fv regions to be displayed outwardly for the effective binding of antigens.

Bionanocapsule-based enzyme-antibody conjugates for enzyme-linked immunosorbent assay.

Macromolecules that can assemble a large number of enzyme and antibody molecules have been used frequently for improvement of sensitivities in enzyme-linked immunosorbent assays (ELISAs). We generated bionanocapsules (BNCs) of approximately 30nm displaying immunoglobulin G (IgG) Fc-binding ZZ domains derived from Staphylococcus aureus protein A (designated as ZZ-BNC). In the conventional ELISA using primary antibody and horseradish peroxidase-labeled secondary antibody for detecting antigen on the solid phase, ZZ-BNCs in the aqueous phase gave an approximately 10-fold higher signal.

A rapid enzyme-linked immunosorbent assay with two modes of detection for measuring cytokine concentration.

Interleukin (IL)-6 and IL-8 were measured in 101 serum samples collected from eight intensive-care unit patients using a polystyrene-based stick enzyme-linked immunosorbent assay (STICKELISA) system. This system consisted of an immobilized-antibody ELISA stick and a noncontact spectrophotometer. Cytokine concentration was detected by two ways: first, rapidly and semi-quantitatively by naked-eye observation of the color change and second, quantitatively using the spectrophotometer for accurate concentration determination.

Secreted CXCL1 is a potential mediator and marker of the tumor invasion of bladder cancer.

Purpose: The purpose of this study was to identify proteins that are potentially involved in the tumor invasion of bladder cancer.

Experimental Design: We searched for the candidate proteins by comparing the profiles of secreted proteins among the poorly invasive human bladder carcinoma cell line RT112 and the highly invasive cell line T24. The proteins isolated from cell culture supernatants were identified by shotgun proteomics.

A novel approach and protocol for discovering extremely low-abundance proteins in serum.

The proteomic analysis of serum (plasma) has been a major approach to determining biomarkers essential for early disease diagnoses and drug discoveries. The determination of these biomarkers, however, is analytically challenging since the dynamic concentration range of serum proteins/peptides is extremely wide (more than 10 orders of magnitude). Thus, the reduction in sample complexity prior to proteomic analyses is essential, particularly in analyzing low-abundance protein biomarkers.

Native polysomes of Saccharomyces cerevisiae in liquid solution observed by atomic force microscopy.

The native polysomes of Saccharomyces cerevisiae were visualized in liquid solution by atomic force microscopy without external contrasting, such as shadowing and negative staining. This study showed native polysomes as lined particle with a height of ca. 27 nm, which is agreement with the height of 80S ribosomes in previous study.

Role for Hsp70 chaperone in Saccharomyces cerevisiae prion seed replication.

The Saccharomyces cerevisiae [PSI+] prion is a misfolded form of Sup35p that propagates as self-replicating cytoplasmic aggregates. Replication is believed to occur through breakage of transmissible [PSI+] prion particles, or seeds, into more numerous pieces. In [PSI+] cells, large Sup35p aggregates are formed by coalescence of smaller sodium dodecyl sulfate-insoluble polymers.

Amino acid residue 184 of yeast Hsp104 chaperone is critical for prion-curing by guanidine, prion propagation, and thermotolerance.

Inactivation of Hsp104 by guanidine is contended to be the mechanism by which guanidine cures yeast prions. We now find an Hsp104 mutation (D184N) that confers resistance to guanidine-curing of the yeast [PSI(+)] prion. In an independent screen we isolated an HSP104 allele altered in the same residue (D184Y) that dramatically impairs [PSI(+)] propagation in a temperature-dependent manner.

Amphipathic property of free thiol group contributes to an increase in the catalytic efficiency of carboxypeptidase Y.

Cys341 of carboxypeptidase Y, which constitutes one side of the solvent-accessible surface of the S1 binding pocket, was replaced with Gly, Ser, Asp, Val, Phe or His by site-directed mutagenesis. Kinetic analysis, using Cbz-dipeptide substrates, revealed that polar amino acids at the 341 position increased K(m) whereas hydrophobic amino acids in this position tended to decrease K(m). This suggests the involvement of Cys341 in the formation of the Michaelis complex in which Cys341 favors the formation of hydrophobic interactions with the P1 side chain of the substrate as well as with residues comprising the surface of the S1 binding pocket.