A case of cryopyrin-associated periodic fever syndrome during canakinumab administration complicated by inflammatory bowel disease.

Cryopyrin-associated periodic fever syndrome (CAPS) is a highly debilitating disorder, which is characterized by unregulated interleukin-1ß production driven by autosomal dominantly inherited mutations in the NLRP3 gene. Patients with CAPS often present with early-onset episodes of fever and rash. These patients also present with variable systemic signs and symptoms, such as arthritis, sensorineural hearing loss, chronic aseptic meningitis, and skeletal abnormalities, but minimal gastrointestinal symptoms. Recently, effective therapies for CAPS targeted against interleukin-1 have become available. We report a case of a young Japanese woman with CAPS who developed inflammatory bowel disease during canakinumab therapy. The patient had colostomy after intestinal perforation and changed canakinumab to infliximab. To the best of our knowledge, this is the first report of a case of inflammatory bowel disease secondary to CAPS complicated by gastrointestinal symptoms and arthritis which canakinumab could not control. Patients with CAPS who have symptoms that cannot be controlled by canakinumab should be considered for possible co-morbidities.

S100A12 and vascular endothelial growth factor can differentiate Blau syndrome and familial Mediterranean fever from systemic juvenile idiopathic arthritis.

OBJECTIVES: Systemic juvenile idiopathic arthritis (sJIA) has recently become regarded as one of the autoinflammatory syndromes (AIS). However, other AIS, such as familial Mediterranean fever (FMF) and Blau syndrome, have been initially misdiagnosed as sJIA because of the clinical similarities. Making the correct diagnosis in the early stage of these AIS is desirable. Therefore, we evaluated serum S100A12 and vascular endothelial growth factor (VEGF) levels to determine if they could be biomarkers for differentiating these AIS. METHOD: Serum S100A12 and VEGF levels were examined in patients with Blau syndrome (n = 4), FMF (n = 4), and sJIA (n = 11) in the active and inactive phases. RESULTS: In the active phase, S100A12 levels were significantly higher in patients with sJIA and FMF compared with those with Blau syndrome (p < 0.001). VEGF levels of patients with sJIA were significantly higher than those of patients with others (p = 0.001). In the inactive phase, there was no significant difference in VEGF levels. However, colchicine-resistant patients or patients without treatment with FMF showed high levels of S100A12 compared with others. CONCLUSIONS: Measuring both serum S100A12 and VEGF levels may be useful for differentiating patients with Blau syndrome and FMF from those with sJIA at the early stage.

Influence of an external electric field on removal of protein fouling on a stainless steel surface by proteolytic enzymes.

Enzymatic cleaning is a potentially useful method for removing proteinaceous fouling from solid surfaces under mild conditions. Herein, the influence of an external electric field on the enzymatic cleaning of a metal surface fouled with a protein was investigated. The model fouling protein (BSA; lysozyme) was prepared on a stainless steel (St) surface, and the resulting surface subjected to enzymatic cleaning with an electric potential being applied to the St plate. Trypsin, α-chymotrypsin, and thermolysin were used as model proteases. The amounts of protein remaining on the plate before and during the cleaning process were measured by means of a reflection absorption technique using Fourier transform infrared spectroscopy. In the case for BSA fouling, the cleaning efficiency of the protease tended to increase at more negative applied potentials. Whereas, there was an optimum applied potential for removing the lysozyme fouling. Atomic force microscopy analyses indicated that applying an adequate range of electric potential enhanced the enzymatic removal of protein fouling inside scratches on the St plate surface. These findings suggest the existence of two modes of electrostatic interactions for the external electric field, one with protease molecules and the other with digested fragments of the fouling protein.

The use of a proteinaceous "cushion" with a polystyrene-binding peptide tag to control the orientation and function of a target peptide adsorbed to a hydrophilic polystyrene surface.

In immobilizing target biomolecules on a solid surface, it is essential (i) to orient the target moiety in a preferred direction and (ii) to avoid unwanted interactions of the target moiety including with the solid surface. The preferred orientation of the target moiety can be achieved by genetic conjugation of an affinity peptide tag specific to the immobilization surface. Herein, we report on a strategy for reducing the extent of direct interaction between the target moiety and surface in the immobilization of hexahistidine peptide (6His) and green fluorescent protein (GFP) on a hydrophilic polystyrene (PS) surface: Ribonuclease HII from Thermococcus kodakaraensis (cHII) was genetically inserted as a "cushion" between the PS-affinity peptide tag and target moiety. The insertion of a cushion protein resulted in a considerably stronger immobilization of target biomolecules compared to conjugation with only a PS affinity peptide tag, resulting in a substantially enhanced accessibility of the detection antibody to the target 6His peptide. The fluorescent intensity of the GFP moiety was decreased by approximately 30% as the result of fusion with cHII and the PS-affinity peptide tag but was fully retained in the immobilization on the PS surface irrespective of the increased binding force. Furthermore, the fusion of cHII did not impair the stability of the target GFP moiety. Accordingly, the use of a proteinaceous cushion appears to be promising for the immobilization of functional biomolecules on a solid surface. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:527-534, 2016.

Prediction of long-term remission of oligo/polyarticular juvenile idiopathic arthritis with S100A12 and vascular endothelial growth factor.

OBJECTIVES: This study aimed to evaluate the usefulness of S100A12 and vascular endothelial growth factor (VEGF) for predicting the stability of remission for discontinuing methotrexate (MTX) and/or biological agents in Japanese patients with oligo/polyarticular juvenile idiopathic arthritis (JIA). METHODS: Forty-four patients with oligo/polyarticular JIA who received MTX with or without biological agents were enrolled. Serum concentration of both S100A12 and VEGF were simultaneously evaluated by ELISA in active and in remission phase determined by activity markers including DAS-28. RESULTS: S100A12 and VEGF were correlated with DAS-28. Of the 22 patients with oligo/polyarticular JIA in clinical remission, 13 patients with low S100A12 and VEGF concentrations could discontinue treatment without relapse over 2 years. However, nine patients without low S100A12 and VEGF concentrations relapsed afterwards, even though they had been in clinical remission. The cut-off levels of S100A12 and VEGF for division into two groups of the maintenance remission and relapse groups were 177 ng/ml and 158 pg/ml, respectively. CONCLUSIONS: S100A12 and VEGF are useful markers for assessing disease activity of oligo/polyarticular JIA in remission phase. These markers should be kept low when clinicians consider tapering or discontinuing treatments in oligo/polyarticular JIA patients.

Safety and efficacy of long-term etanercept in the treatment of methotrexate-refractory polyarticular-course juvenile idiopathic arthritis in Japan.

OBJECTIVES: Previous short-term trials found etanercept (0.2 or 0.4 mg/kg) to be effective and well tolerated in Japanese children with juvenile idiopathic arthritis (JIA) who were intolerant/resistant to methotrexate. The aim of this study was to evaluate the long-term safety and efficacy of etanercept in Japanese children with JIA. METHODS: Patients (4-19 years) who received etanercept in one of three short-term studies continued onto this long-term open-label study. RESULTS: Of the 32 patients enrolled, 18 (56.3%) completed 192 weeks of the study and 14 (43.8%) were discontinued; 7 (21.9%) for patient refusal, 2 (6.3%) for adverse events (AEs), and 5 (15.6%) for lack of efficacy. All patients reported AEs; 31 (96.9%) reported infections and 6 (18.8%) reported serious AEs. Main efficacy assessments included change from baseline in the American College of Rheumatology Pediatric core components, including mean improvements from baseline in the physician global assessment (90.7%), patient/guardian global assessments (54.1%), Childhood Health Assessment Questionnaire (84.6%), and median improvements in C-reactive protein levels (92.7%). No unexpected safety results were reported, and early efficacy responses were sustained in the long term. CONCLUSIONS: This study provides further evidence that etanercept is an effective therapeutic option for Japanese children with polyarticular-course JIA.

Etanercept in the treatment of disease-modifying anti-rheumatic drug (DMARD)-refractory polyarticular course juvenile idiopathic arthritis: experience from Japanese clinical trials.

Efficacy, safety, and pharmacokinetics results from 4 studies-3 open-label (OL) and 1 randomized double-blind (DB)-have provided data for approval of etanercept for treatment of disease-modifying anti-rheumatic drug (DMARD)-refractory juvenile idiopathic arthritis (JIA) in Japan. Results from the 3 shorter-term (2 OL and 1 DB) studies are reported here. Subjects (4-17 years) enrolled in the OL studies had active JIA, i.e. ≥5 swollen joints and ≥3 joints with limitation of motion and pain or tenderness. Subjects enrolled in the primary OL study received etanercept 0.4 mg/kg subcutaneously twice weekly; in the lower-dose OL study subjects received etanercept 0.2 mg/kg. Subjects in the primary OL study who completed ≥48 weeks could continue into a 12-week DB dose-down extension study in which subjects received etanercept 0.4 or 0.2 mg/kg twice weekly. The primary endpoint in all 3 studies, i.e. 30% improvement in the American College of Rheumatology criteria for JIA (ACR Pedi 30) at 12 weeks, was achieved by ≥80% of subjects by week 2 and sustained to week 12. Common adverse events reported were injection site reactions, nasopharyngitis, and gastroenteritis. These results provide further evidence that etanercept is effective therapy for DMARD-refractory polyarticular JIA patients.

Purification, characterization, molecular cloning, and expression of a new aminoacylase from Streptomyces mobaraensis that can hydrolyze N-(middle/long)-chain-fatty-acyl-L-amino acids as well as N-short-chain-acyl-L-amino acids.

We report here on the purification, characterization, molecular cloning, and expression of a new aminoacylase, initially isolated from the supernatant of Streptomyces mobaraensis (Sm-AA). Purified wild-type Sm-AA was found to be a monomeric protein with a molecular mass of 55 kDa. The cloned gene of Sm-AA contained an ORF of 1,383 bp, encoding a polypeptide of 460 amino acids. A BLAST search revealed that Sm-AA belongs to the peptidase M20 family, with identities to a hypothetical protein from Streptomyces pristinaespiralis, a putative peptidase from Streptomyces avermitilis, peptidase M20 from Frankia sp., succinyl-diaminopimelate desuccinylase from Hemophilus influenzae, and aminoacylase-1 from porcine kidney at 89, 88, 67, 29, and 25% respectively. The Sm-AA gene was subcloned into an expression vector, pSH19, and was expressed in Streptomyces lividans TK24. The amount of the recombinant Sm-AA expressed in the S. lividans cells was approximately 42-fold higher than that of Sm-AA found in the supernatant of S. mobaraensis. Sm-AA showed high hydrolytic activity towards various N-acetyl-L-amino acids and N-(middle/long)-chain-fatty-acyl-L-amino acids, with a preference for the acyl derivatives of L-Met, L-Ala, L-Cys, etc. with an optimum pH and temperature for reaction of about 7.5 and 50 degrees Celsius (at pH 7.5).

Temperature scanning FTIR analysis of interactions between sugar and polymer additive in amorphous sugar-polymer mixtures.

The impact of a polymer additive (polyvinylpyrrolidone, PVP) on hydrogen bonding in amorphous sugar matrices as well as on the glass transition temperature, T(g), were examined by temperature scanning Fourier transform infrared spectroscopy (TS-FTIR). An amorphous sugar matrix containing PVP was prepared by air-drying an aqueous solution of a sugar-PVP mixture. The hydrogen bonds in the sugar-PVP mixture (sugar-PVP and sugar-sugar hydrogen bonds) were analyzed from the IR peak positions corresponding to the stretching vibration of C==O groups of PVP and O--H groups of the sugar and the temperature dependence of the peak position of the O--H stretching vibration band. The addition of PVP to amorphous mono and disaccharides significantly lowered the extent of hydrogen bond formation while interactions between sugars and the PVP tended to prevent the disruption of hydrogen bonds due to increasing temperature, the magnitude of which was larger for larger oligomers. The T(g) value for the amorphous sugar was increased by the addition of PVP in many cases. As the size of sugar molecule became larger, the relative magnitude of the increased T(g) by PVP to the difference between the T(g) values for sugar alone and PVP alone became larger and then reached a certain level; it was slight in the case of glucose. Collectively, these results demonstrate that the magnitude of the impact of PVP on an amorphous sugar matrix strongly vary and are dependent on the types of sugar.

Switching the therapy from etanercept to infliximab in a child with rheumatoid factor positive polyarticular juvenile idiopathic arthritis.

Tumor necrosis factor alpha (TNFalpha)-blocking agents have been used increasingly in the treatment of severe refractory juvenile idiopathic arthritis (JIA). However, some patients have been forced to discontinue these agents because of the lack of efficacy or adverse events. In these situations, cases of switching from one TNF-blocking agent to another are reported in rheumatoid arthritis, but there are few cases in JIA. This report documents the case of a patient with JIA who improved following a switch from etanercept to infliximab.

TPR domain of Ser/Thr phosphatase of Aspergillus oryzae shows no auto-inhibitory effect on the dephosphorylation activity.

A Ser/Thr phosphatase gene cloned from Aspergillus oryzae, aoppt, revealed that the tetratricopeptide repeat (TPR) and catalytic domains of the full-length AoPPT are located at the N- and C-terminal regions, respectively, similar to those of human Ser/Thr phosphatase 5 (PP5) and yeast Ppt1. Four different regions of AoPPT, namely, a full-length polypeptide, the catalytic domain, the catalytic domain plus C-terminal 15 amino-acid residues and the TPR domain were expressed in Escherichia coli and their roles in dephosphorylation activity were examined, using p-nitrophenyl phosphate as the substrate. The full-length AoPPT showed the highest dephosphorylation activity while the catalytic domain had the lowest activity. The activity of the catalytic domain was not inhibited by the presence of the TPR domain and arachidonic acid did not increase the activity of the full-length enzyme. These findings suggest that the integrity of the entire enzyme would be necessary for its full activity to be expressed.

Cloning and characterization of penicillin V acylase from Streptomyces mobaraensis.

We report on the molecular cloning and characterization of penicillin V acylase (PVA) from an actinomycete, Streptomyces mobaraensis (Sm-PVA), which was originally isolated as an acylase that efficiently hydrolyzes the amide bond of various N-fatty-acyl-l-amino acids and N-fatty-acyl-peptides as well as capsaicin (8-methyl-N-vanillyl-6-nonenamide). In addition, the purified Sm-PVA hydrolyzed penicillin V with the highest activity (k(cat)) among the PVAs so far reported, penicillin G, and 2-nitro-5-phenoxyacetamide benzoic acid. The BLAST search revealed that the Sm-PVA precursor is composed of a polypeptide that is characteristic of enzymes belonging to the beta-lactam acylase family with four distinct segments; a signal sequence (43 amino acids), an alpha subunit (173 amino acids), a linker peptide (28 amino acids), and a beta subunit (570 amino acids). The mature, active Sm-PVA is a heterodimeric protein with alpha and beta subunits, in contrast to PVAs isolated from Bacillus sphaericus and B. subtilis, which have a homotetrameric structure. The amino acid sequence of Sm-PVA showed identities to PVA from S. lavendulae, N-acylhomoserine lactone-degrading acylase from Streptomyces sp., cyclic lipopeptide acylase from Streptomyces sp., and aculeacin A acylase from Actinoplanes utahensis with 68, 67, 67, and 41% identities, respectively.

Development of a one-step ELISA method using an affinity peptide tag specific to a hydrophilic polystyrene surface.

Glutathione S-transferase genetically fused with an affinity peptide tag, PS19 (RAFIASRRIKRP) having a specific affinity for a hydrophilic polystyrene (PS) surface, was preferentially immobilized on a hydrophilic PS (phi-PS) plate without suffering from interference by coexisting protein molecules. Furthermore, rabbit IgG chemically conjugated with a peptide, KPS19R10, in which (10)Lys in PS19 was replaced with Arg and one Lys residue was added at the N-terminus as a coupling site for glutaraldehyde, showed a higher immobilization affinity to the phi-PS plate than that conjugated with the PS19 peptide. On the basis of these findings, the use of a phi-PS plate and peptide tag-linked ligand proteins permitted a one-step or two-step enzyme-linked immunosorbent assay (ELISA) to be achieved, resulting in a substantial reduction in operational time compared with the conventional ELISA method using a hydrophobic PS (pho-PS) plate, while maintaining a high sensitivity. Furthermore, the sensitivity was increased to a greater extent compared to the conventional ELISA meihod when the one-step ELISA was applied to the detection of bovine insulin in a sandwich mode, due to the reduced number of washing and incubation steps. The method proposed here would be a versatile method for use in various ELISA techniques such as sandwich and competitive ELISAs using an antigen, an antibody and streptavidin that are genetically fused or chemically conjugated with the PS-specific affinity peptide as the ligand protein.

Protein-protein interaction analysis using an affinity peptide tag and hydrophilic polystyrene plate.

A sandwich ELISA method using peptide tags showing a specific affinity to a hydrophilic polystyrene surface (PS-tags), PS 19 composed of RAFIASRRIKRP and KPS19R10 of KRAFIASRRIRRP and a hydrophilic polystyrene (phi-PS) plate was used to analyze protein-protein interactions. An Escherichia coli cysteine synthase complex, in which serine acetyltransferase (SAT) interacts with O-acetylserine sulfhydrylase-A (OASS) was used as a model system. When the interaction was detected by the conventional sandwich ELISA method using a hydrophobic polystyrene (pho-PS) plate, for the exclusive use of ELISA, the signal intensity was barely detectable due to conformational change of the ligand protein, OASS in the adsorbed state. On the contrary, when OASS, genetically fused with PS19 (OASS-PS19) or chemically conjugated with KPS19R10 (OASS-KPS19R10), was immobilized on the phi-PS plate, a high signal intensity was detected. Furthermore, by applying the two-step sandwich ELISA, in which OASS-PS19 or OASS-KPS19R10 formed a complex with SAT in the blocking solution before immobilization on the phi-PS plate, the signal intensity was further increased with a much shorter operational time, because SAT in the blocking solution formed a complex with OASS-PS19 or OASS-KPS19R10 without any steric hindrance.

Screening and characterization of affinity peptide tags specific to polystyrene supports for the orientated immobilization of proteins.

Dodecapeptides that exhibit a high affinity specific to a polystyrene surface (PS-tags) were screened using an Escherichia coli random peptide display library system, and the compounds were used as a peptide tag for the site-specific immobilization of proteins. The various PS-tags obtained after 10 rounds of biopanning selection were mainly composed of basic and aliphatic amino acid residues, most of which were arranged in close proximity to one another. Mutant-type glutathione S-transferases (GSTs) fused with the selected PS-tags, PS19 (RAFIASRRIKRP) and PS23 (AGLRLKKAAIHR) at their C-terminus, GST-PS19 and GST-PS23, when adsorbed on the PS latex beads had a higher affinity than the wild-type GST, and the specific remaining activity of the immobilized mutant-type GSTs was approximately 10 times higher than that of the wild-type GST. The signal intensity detected for GST-PS19 and GST-PS23 adsorbed on hydrophilic and hydrophobic PS surfaces using an anti-peptide antibody specific for the N-terminus peptide of GST was much higher than that for the wild-type GST. These findings indicate that the mutant-type GSTs fused with the selected peptide tags, PS19 and PS23, could be site-specifically immobilized on the surface of polystyrene with their N-terminal regions directed toward the solution. Thus, the selected peptide tags would be useful for protein immobilization in the construction of enzyme-linked immunosorbent assay (ELISA) systems and protein-based biochips.

Cloning, overexpression, purification, and characterization of O-acetylserine sulfhydrylase-B from Escherichia coli.

O-Acetylserine sulfhydrylase-B (OASS-B, EC 2.5.1.47) is one of the two isozymes produced by Escherichia coli that catalyze the synthesis of L-cysteine from O-acetyl-L-serine and sulfide. The cysM gene encoding OASS-B was cloned and the enzyme was overexpressed in E. coli using pUC19 with a lacUV5 promoter. The enzyme was purified to homogeneity, as evidenced by SDS-PAGE. Approximately 300 mg of purified OASS-B was obtained from 1600 mL of culture broth with a purification yield of 60% or higher. The purified OASS-B was characterized and its properties compared with OASS-A. OASS-B did not form a complex with E. coli serine acetyltransferase (SAT, EC 2.3.1.30) and showed a wide range of substrate specificity in nonproteinaceous amino acid synthesis.

A novel acylase from Streptomyces mobaraensis that efficiently catalyzes hydrolysis/synthesis of capsaicins as well as N-acyl-L-amino acids and N-acyl-peptides.

A novel enzyme that catalyzes efficient hydrolysis of capsaicin (8-methyl-N-vanillyl-6-nonenamide) was isolated from the culture broth of Streptomyces mobaraensis. The enzyme consisted of two dissimilar subunits with molecular masses of 61 and 19 kDa. The enzyme was activated and stabilized in the presence of Co2+. It showed a pH optimum of about 8 and was stable at temperatures of up to 55 degrees C for 1 h at pH 7.8. The specific activity of the enzyme for the hydrolysis of capsaicin was 10(2)-10(4) times higher than those for the enzymes reported to date. In an aqueous/n-hexane biphasic system, capsaicin analogues such as octanoyl, decanoyl, and lauroyl vanillylamides were synthesized from the corresponding fatty acids and vanillylamine at yields of 50% or greater. In addition, the enzyme catalyzed the deacylation of N-lauroyl-L-amino acids and N-lauroyl-L-dipeptides and the efficient synthesis of Nalpha-lauroyl-L-lysine, Nepsilon-lauroyl-L-lysine, and various N-lauroyl-peptides in aqueous solution in both the absence and the presence of glycerol.

On the interaction site of serine acetyltransferase in the cysteine synthase complex from Escherichia coli.

Cysteine synthase from Escherichia coli is a bienzyme complex comprised of serine acetyltransferase (SAT) and O-acetylserine sulfhydrylase A. The site of interaction of a SAT molecule was investigated by gel chromatography and surface plasmon technique using various mutant-type SATs, to better understand the mechanism involved in complex formation. The C-terminus of SAT, Ile 273, along with Glu 268 and Asp 271, was found to be essential for complex formation. The effects of O-acetyl-L-serine and sulfide on the affinity for the complex formation were also studied using a surface plasmon technique.

Efficacy of mizoribine in the treatment of systemic lupus erythematosus in children.

BACKGROUND: Mizoribine (MZR) is a novel immunosuppressant developed in Japan. As MZR is reported to be less toxic than other cytotoxic drugs, it is frequently used in Japan in the treatment of adult patients with rheumatoid arthritis or lupus nephritis. The objective of this study was to evaluate the efficacy of MZR in children with SLE. Nine female children with lupus nephritis who had undergone renal biopsy before starting MZR, were involved in this study. Their mean disease duration was 4.8 years at the time MZR treatment was initiated. Patients who had received intensive medications, such as methyl-prednisolone pulse therapy, intravenous cyclophosphamide pulse therapy, and/or other immunosuppressants, within the 4 months prior to the start of the study, were excluded. METHODS: Patients treated with 3 mg/kg per day of MZR were monitored every month for up to 1 year. The efficacy of MZR was evaluated by the changes from baseline values of serum C3, serum C4, anti-dsDNA antibody titer, erythrocyte sedimentation rate (ESR), urinary protein, dosage of prednisolone (PSL), and the sum of the scores defined by these parameters. RESULTS: Favorable changes were observed in C3 and ESR after 2 months and 3 months of MZR therapy, respectively. At 3 months of MZR therapy, the sum of scores defined by the parameters for disease activity indicated that MZR was more effective in non-class IV nephritis patients (n = 5) than in class IV nephritis patients (n = 4) (P = 0.0197). All nine children involved in the study tolerated the MZR therapy well during the study. CONCLUSION: MZR was safe in lupus children, but its efficacy was limited in patients with non-class IV nephritis. Further study is necessary, in which higher dosages and/or earlier use of MZR is provided to a larger number of children.