Potential Efficacy of Janus Kinase Inhibitors in the Treatment of a Patient With Coexisting Peripheral and Axial Spondyloarthritis and Ulcerative Colitis.

Tumor necrosis factor inhibitors are effective and recommended in treating patients with coexisting spondyloarthritis (SpA) and ulcerative colitis (UC); however, the evidence of their superiority over other drugs is insufficient.1 Although Janus kinase inhibitors (JAKi) have shown effectiveness in treating UC and psoriatic arthritis, there are no reports of treating coexisting SpA and UC with JAKi monotherapy.

Direct conversion of a general antibody to its catalytic antibody and corresponding applications -Importance and role of Pro95 in CDR-3.

Catalytic antibodies possess unique features capable of both recognizing and enzymatically degrading antigens. Therefore, they are more beneficial than monoclonal antibodies (mAbs). Catalytic antibodies exhibit the ability to degrade peptides, antigenic proteins, DNA, and physiologically active molecules. However, they have a significant drawback in terms of their production. The production of a desired catalytic antibody has extensive costs, in terms of time and effort. We herein describe an evolutionary method to produce a desired catalytic antibody via conversion of a general antibody by the deletion of Pro95, which resides in complementarity-determining region-3. As over thousands of mAbs have been produced since 1975, using the novel technology discussed herein, the catalytic feature cleaving the antigen can be conferred to the mAb. In this review article, we discussed in detail not only the role of Pro95 but also the unique features of the converted catalytic antibodies. This technique will accelerate research on therapeutic application of catalytic antibodies.

Obtaining Highly Active Catalytic Antibodies Capable of Enzymatically Cleaving Antigens.

A catalytic antibody has multiple functions compared with a monoclonal antibody because it possesses unique features to digest antigens enzymatically. Therefore, many catalytic antibodies, including their subunits, have been produced since 1989. The catalytic activities often depend on the preparation methods and conditions. In order to elicit the high catalytic activity of the antibodies, the most preferable methods and conditions, which can be generally applicable, must be explored. Based on this view, systematic experiments using two catalytic antibody light chains, #7TR and H34, were performed by varying the purification methods, pH, and chemical reagents. The experimental results obtained by peptidase activity tests and kinetic analysis, revealed that the light chain's high catalytic activity was observed when it was prepared under a basic condition. These data imply that a small structural modulation of the catalytic antibody occurs during the purification process to increase the catalytic activity while the antigen recognition ability is kept constant. The presence of NaCl enhanced the catalytic activity. When the catalytic light chain was prepared with these preferable conditions, #7TR and H34 hugely enhanced the degradation ability of Amyloid-beta and PD-1 peptide, respectively.

Acute generalized pustular bacterid concomitant with erythema nodosum, polyarthritis, and Achilles tendinitis.

We report a case of acute generalized pustular bacterid (AGPB) concomitant with erythema nodosum (EN), polyarthritis, and Achilles tendinitis. The patient was admitted with a complaint of fever, widespread plural pustules, erythema, and polyarthralgia. Histopathological examination of the skin lesions demonstrated features of AGBP and EN. Although arthralgia and AGPB can be recognized together, EN and Achilles tendinitis are rare manifestations seen in patients with AGPB. In this case report, we suggest arthralgia, EN, and Achilles tendinitis could coexist with AGPB.

Role of the constant region domain in the structural diversity of human antibody light chains.

Issues regarding the structural diversity (heterogeneity) of an antibody molecule have been the subject of discussion along with the development of antibody drugs. Research on heterogeneity has been extensive in recent years, but no clear solution has been reached. Heterogeneity is also observed in catalytic antibody κ light chains (CLs). In this study, we investigated how the constant region domain of CLs concerns structural diversity because it is a simple and good example for elucidating heterogeneity. By means of cation-exchange chromatography, SDS-PAGE, and 2-dimensional electrophoresis for the CL, multimolecular forms consisting of different electrical charges and molecular sizes coexisted in the solution, resulting in the similar heterogeneity of the full length of CLs. The addition of copper ion could cause the multimolecular forms to change to monomolecular forms. Copper ion contributed greatly to the enrichment of the dimer form of CL and the homogenization of the differently charged CLs. Two molecules of the CL protein bound one copper ion. The binding affinity of the ion was 48.0 µM-1 Several divalent metal ions were examined, but only zinc showed a similar effect.-Hifumi, E., Taguchi, H., Kato, R., Uda, T. Role of the constant region domain in the structural diversity of human antibody light chains.

Pneumocystis jirovecii pneumonia developed in a patient with rheumatoid arthritis after 14 weeks of iguratimod add-on to treatment with methotrexate and etanercept.

A 66-year-old woman who had rheumatoid arthritis and underwent a long-term treatment with methotrexate and etanercept developed Pneumocystis jirovecii pneumonia (PCP) 3 months after iguratimod add-on. Although most rheumatologists might have the impression that iguratimod has less toxicity and immunosuppressive effect compared with methotrexate and biologic disease-modifying antirheumatic drugs, this case suggests that iguratimod may increase the risk of PCP, especially in combination with other drugs.

Specific amyloid ß clearance by a catalytic antibody construct.

Classical immunization methods do not generate catalytic antibodies (catabodies), but recent findings suggest that the innate antibody repertoire is a rich catabody source. We describe the specificity and amyloid ß (Aß)-clearing effect of a catabody construct engineered from innate immunity principles. The catabody recognized the Aß C terminus noncovalently and hydrolyzed Aß rapidly, with no reactivity to the Aß precursor protein, transthyretin amyloid aggregates, or irrelevant proteins containing the catabody-sensitive Aß dipeptide unit. The catabody dissolved preformed Aß aggregates and inhibited Aß aggregation more potently than an Aß-binding IgG. Intravenous catabody treatment reduced brain Aß deposits in a mouse Alzheimer disease model without inducing microgliosis or microhemorrhages. Specific Aß hydrolysis appears to be an innate immune function that could be applied for therapeutic Aß removal.

6-(4-Amino-2-butyl-imidazoquinolyl)-norleucine: Toll-like receptor 7 and 8 agonist amino acid for self-adjuvanting peptide vaccine.

Generally, small peptides by themselves are weak to induce antibody responses. Toll-like receptor (TLR) ligands are attractive candidates of vaccine adjuvants to improve their antigenicity. The covalent conjugation of TLR ligands with antigens to produce self-adjuvanting peptide vaccine is a promising approach. Based on the structure of TLR7/8 ligands, a series of synthetic amino acids 6-imidazoquinolyl-norleucines were synthesized, wherein an imidazoquinoline structure as the TLR7/8 agonistic pharmacophores was constructed on the ε-NH2 group of Lys. Of them, 6-(4-amino-2-butyl-imidazoquinolyl)-norleucine showed the most potent TLR7 and TLR8 agonistic activities with EC50 values of 8.55 and 106 µM, respectively. Subsequently, mice were immunized with the influenza A virus M2e antigen mixed with or covalently conjugated to the TLR7/8 agonist amino acid, which led to induction of M2e specific antibody productions in the absence of other adjuvant. We successfully developed a novel efficient tool for self-adjuvanting peptide vaccines targeting TLR7/8.

Development of an activity-based probe for amyloid ß-hydrolyzing antibodies.

We report developing an activity-based probe containing an amyloid ß peptide (Aß) 17-27 and an electrophilic phosphonate diester at the C-terminus. A probe containing an electrophilic moiety is able to react with the nucleophiles on an antibody or an antibody with proteinase activity. The probe reacted with an Aß specific monoclonal antibody and formed a covalent complex. The covalent binding also occurred specifically when the probe reacted with serum containing anti-Aß antibodies. These results suggest that the probe would serve as a powerful tool to isolate Aß specific antibodies that are capable of Aß hydrolysis activity.

[A Case of Leptospirosis in which the Causative Pathogen was Detected Using Cerebrospinal Fluid PCR Eight Days after Onset].

We report a patient with leptospirosis caused by infection with Leptospira interrogans serovar Rachmati. A 30-year-old Japanese man took part in a survival camp on Iriomote Island, Okinawa, from July 9 to July 15, 2014. During the camp, he swam in the river and kayaked. He developed a high fever and fatigue 7 days after completing his trip and was admitted to our hospital on July 22. On admission, he complained of a posterior cervical pain and a loss of appetite. Laboratory findings revealed granulocytosis, mildly elevated AST and ALT levels, elevated BUN and Cr levels, and a significantly elevated CRP level. No pathogenic bacteria were isolated from blood, urine, or cerebrospinal fluid cultures. We included leptospirosis in the differential diagnosis because of the patient's history of participating in a survival camp on Iriomote Island. Minocycline 200 mg, p.o. showed an excellent efficacy. The Leptospira flagellar gene FlaB was detected using a cerebrospinal fluid PCR. A microscopic agglutination test (MAT) during the convalescent stage demonstrated significant increases in antibodies against L. interrogans serovar Rachmati, confirming the diagnosis of leptospirosis. A medical history including occupation and recent travel history, and an adequate specimen sampling are crucial for the accurate and early diagnosis of leptospirosis.

Enzymatization of mouse monoclonal antibodies to the corresponding catalytic antibodies.

Catalytic antibodies possess a dual function that enables both antigen recognition and degradation. However, their time-consuming preparation is a significant drawback. This study developed a new method for quickly converting mice monoclonal antibodies into catalytic antibodies using site-directed mutagenesis. Three mice type monoclonal antibodies targeting hemagglutinin molecule of influenza A virus could be transformed into the catalytic antibodies by deleting Pro95 in CDR-3 of the light chain. No catalytic activity was observed for monoclonal antibodies and light chains. In contrast, the Pro95-deleted light chains exhibited a catalytic activity to cleave the antigenic peptide including the portion of conserved region of hemagglutinin molecule. The affinity of the Pro95-deleted light chains to the antigen increased approximately 100-fold compared to the wild-type light chains. In the mutants, three residues (Asp1, Ser92, and His93) come closer to the appropriate position to create the catalytic site and contributing to the enhancement of both catalytic function and immunoreactivity. Notably, the Pro95-deleted catalytic light chains could suppress influenza virus infection in vitro assay, whereas the parent antibody and the light chain did not. This strategy offers a rapid and efficient way to create catalytic antibodies from existing antibodies, accelerating the development for various applications in diagnostic and therapeutic applications.

Reduced versus maximum tolerated methotrexate dose concomitant with adalimumab in patients with rheumatoid arthritis (MIRACLE): a randomised, open-label, non-inferiority trial.

BACKGROUND: Efficacy of combination therapy with methotrexate and biological disease-modifying antirheumatic drugs is well established in the management of patients with rheumatoid arthritis; however, the optimal dose of methotrexate to administer with a tumour necrosis factor inhibitor remains unclear. We aimed to clarify the efficacy and safety of adalimumab combined with reduced methotrexate dose compared with the maximum tolerated methotrexate dose in patients with rheumatoid arthritis and an inadequate response to methotrexate monotherapy. METHODS: In this open-label, randomised controlled trial, we recruited methotrexate-naive patients with rheumatoid arthritis and a disease duration of less than 2 years across 24 secondary or tertiary care hospitals across Japan, South Korea, and Taiwan. At initiation, methotrexate was given orally and increased to the maximum tolerated dose by week 12. Patients who did not achieve remission on the basis of the Simplified Disease Activity Index (SDAI) at week 24 were randomly assigned (1:1) to receive adalimumab (40 mg biweekly) combined with a continued maximum tolerated dose of methotrexate or adalimumab combined with a reduced dose of methotrexate. The primary endpoint was non-inferiority of adalimumab plus reduced-dose methotrexate to adalimumab plus maximal-dose methotrexate based on SDAI remission at week 48, assessed in the modified full-analysis set with a pre-specified non-inferiority margin of -15%, based on a two-sided 90% CI. Adverse events were assessed in the safety analysis set. This trial is registered with ClinicalTrials.gov, NCT03505008 and has been completed. FINDINGS: From April 18, 2018, to June 2, 2020, from 323 patients screened, 300 were enrolled, and 291 patients were included in the full analysis set. The mean age was 57·7 years (SD 15·2), 217 (75%) were female, 74 (25%) were male, and all patients were of Asian ethnicity. The mean SDAI at study enrolment was 26·5 (SD 12·4). 52 patients discontinued the study before week 24 or at week 24 before randomisation. At week 24, 105 (36%) of 291 patients achieved remission and continued methotrexate monotherapy through week 48. 134 (46%) did not achieve remission at week 24 and were randomly assigned to receive adalimumab plus the maximum tolerated dose of methotrexate (n=68) or adalimumab plus reduced-dose methotrexate (n=66). Remission at week 48 was achieved in 25 (38%) of 66 and 27 (44%) of 61 patients, respectively, with an adjusted risk difference of 6·4% (90% CI -7·0 to 19·8), which met the non-inferiority margin of -15%. Adverse events after week 24 tended to be more frequent in the maximum tolerated dose group than in the reduced-dose group (24 [35%] vs 13 [20%], p=0·054). Between week 24 and 48, there were 14 serious adverse events (6 in the methotrexate monotherapy group, 5 in the adalimumab plus maximal-dose methotrexate, and 3 in the adalimumab plus reduced-dose methotrexate group), and no deaths. INTERPRETATION: The MIRACLE study showed that the efficacy of adalimumab combined with reduced methotrexate dose was not inferior to that with the maximum tolerated methotrexate dose, with a tendency to a better safety profile. FUNDING: Eisai.

Synthesis and electronic, photophysical, and electrochemical properties of a series of thienylcarbazoles.

A series of thienylcarbazoles were synthesized by Suzuki-Miyaura and Ullmann coupling reactions. In these compounds, the 2-thienyl or 2,2'-bithiophen-5-yl group is connected at the N-, 1,8-, 3,6-, 2,7-, 2,7,N-, or 1,8,N-positions of the carbazole ring. The effects of structural variations on their electronic, photophysical, and electrochemical properties were explored by UV-vis and fluorescence spectroscopies, cyclic voltammetry (CV), and DFT calculations in evaluation of their potential as material components. The thienyl substituents at the 2,7-positions in 4, 5, and 10 are responsible for a high degree of π-conjugation and strong emission with fluorescence quantum yields up to 0.61. The CV on a series of thienylcarbazoles revealed a good electron-donating ability of 3,6-substituted carbazoles 3 and 9. The number of thiophene units was found to affect the extent of π-conjugation, the resulting HOMO-LUMO gaps, and fluorescence efficiency. The crystal structures of 5 and 9 were also disclosed.

A new catalytic site functioning in antigen cleavage by H34 catalytic antibody light chain.

The cleavage reactions of catalytic antibodies are mediated by a serine protease mechanism involving a catalytic triad composed of His, Ser, and Asp residues, which reside in the variable region. Recently, we discovered a catalytic antibody, H34 wild type (H34wt), that is capable of enzymatically cleaving an immune-check point PD-1 peptide and recombinant PD-1; however, H34wt does not contain His residues in the variable region. To clarify the reason behind the catalytic features of H34wt and the amino acid residues involved in the catalytic reaction, we performed site-directed mutagenesis focusing on the amino acid residues involved in the cleavage reaction, followed by catalytic activity tests, immunological reactivity evaluation, and molecular modeling. The results revealed that the cleavage reaction by H34wt proceeds through the action of a new catalytic site composed of Arg, Thr, and Gln. This new scheme differs from that of the serine protease mechanism of catalytic antibodies.

Electrostatically-sprayed carbon electrodes for high performance organic complementary circuits.

Organic thin-film transistors (OTFTs) are promising building blocks of flexible printable electronic devices. Similar to inorganic FETs, OTFTs are heterostructures consisting of metals, insulators, and semiconductors, in which nanoscale interfaces between different components should be precisely engineered. However, OTFTs use noble metals, such as gold, as electrodes, which has been a bottleneck in terms of cost reduction and low environmental loading. In this study, we demonstrate that graphite-based carbon electrodes can be deposited and patterned directly onto an organic single-crystalline thin film via electrostatic spray coating. The present OTFTs exhibited reasonably high field-effect mobilities of up to 11 cm2 V-1 s-1 for p-type and 1.4 cm2 V-1 s-1 for n-type with no significant deterioration during electrostatic spray processes. We also demonstrate two significant milestones from the viewpoint of material science: a complementary circuit, an inverter consisting of p- and n-type OTFTs, and an operatable metal-free OTFT composed of fully carbon-based materials. These results constitute a key step forward in the further development of printed metal-free integrated circuits.

Finding and characterizing a catalytic antibody light chain, H34, capable of degrading the PD-1 molecule.

Programmed cell death 1 (PD-1) is an immune checkpoint molecule regulating T-cell function. Preventing PD-1 binding to its ligand PD-L1 has emerged as an important tool in immunotherapy. Here, we describe a unique human catalytic antibody light chain, H34, which mediates enzymatic degradation of human PD-1 peptides and recombinant human PD-1 protein and thus functions to prevent the binding of PD-1 with PD-L1. H34 degraded one half of the PD-1 molecules within about 6 h under the experimental conditions. Investigating the acquisition of the catalytic function by H34, which belongs to subgroup I and lacks a Pro95 residue in CDR-3, revealed the importance of this sequence, as a Pro95-reconstituted mutant (H34-Pro95(+)) exhibited very little catalytic activity to cleave PD-1. Interestingly, EDTA inhibited the catalytic activity of H34, which could work as a metallo-protease. Zn2+ or Co2+ ions may work as a cofactor. It is meaningfull that H34 was obtained from the human antibody gene taken from a healthy volunteer, suggesting that we potentially have such unique molecules in our body.

Toward effective HIV vaccination: induction of binary epitope reactive antibodies with broad HIV neutralizing activity.

We describe murine monoclonal antibodies (mAbs) raised by immunization with an electrophilic gp120 analog (E-gp120) expressing the rare ability to neutralize genetically heterologous human immunodeficiency virus (HIV) strains. Unlike gp120, E-gp120 formed covalent oligomers. The reactivity of gp120 and E-gp120 with mAbs to reference neutralizing epitopes was markedly different, indicating their divergent structures. Epitope mapping with synthetic peptides and electrophilic peptide analogs indicated binary recognition of two distinct gp120 regions by anti-E-gp120 mAbs, the 421-433 and 288-306 peptide regions. Univalent Fab and single chain Fv fragments expressed the ability to recognize both peptides. X-ray crystallography of an anti-E-gp120 Fab fragment revealed two neighboring cavities, the typical antigen-binding cavity formed by the complementarity determining regions (CDRs) and another cavity dominated by antibody heavy chain variable (V(H)) domain framework (FR) residues. Substitution of the FR cavity V(H) Lys-19 residue by an Ala residue resulted in attenuated binding of the 421-433 region peptide probe. The CDRs and V(H) FR replacement/silent mutation ratios exceeded the ratio for a random mutation process, suggesting adaptive development of both putative binding sites. All mAbs studied were derived from V(H)1 family genes, suggesting biased recruitment of the V gene germ line repertoire by E-gp120. The conserved 421-433 region of gp120 is essential for HIV binding to host CD4 receptors. This region is recognized weakly by the FR of antibodies produced without exposure to HIV, but it usually fails to induce adaptive synthesis of neutralizing antibodies. We present models accounting for improved CD4-binding site recognition and broad HIV neutralizing activity of the mAbs, long sought goals in HIV vaccine development.