X‐ray crystal structure localizes the mechanism of inhibition of an IL‐36R antagonist monoclonal antibody to interaction with Ig1 and Ig2 extra cellular domains

Cellular signaling via binding of the cytokines IL‐36α, β, and γ along with binding of the accessory protein IL‐36RAcP, to their cognate receptor IL‐36R is believed to play a major role in epithelial and immune cell‐mediated inflammation responses. Antagonizing the signaling cascade that results from these binding events via a directed monoclonal antibody provides an opportunity to suppress such immune responses. We report here the molecular structure of a complex between an extracellular portion of human IL‐36R and a Fab derived from a high affinity anti‐IL‐36R neutralizing monoclonal antibody at 2.3 Å resolution. This structure, the first of IL‐36R, reveals similarities with other structurally characterized IL‐1R family members and elucidates the molecular determinants leading to the high affinity binding of the monoclonal antibody. The structure of the complex reveals that the epitope recognized by the Fab is remote from both the putative ligand and accessory protein binding interfaces on IL‐36R, suggesting that the functional activity of the antibody is noncompetitive for these binding events.     

Benzimidazolone as potent chymase inhibitor: modulation of reactive metabolite formation in the hydrophobic (P1) region

A new class of chymase inhibitor featuring a benzimidazolone core with an acid side chain and a P₁ hydrophobic moiety is described. Incubation of the lead compound with GSH resulted in the formation of a GSH conjugate on the benzothiophene P₁ moiety. Replacement of the benzothiophene with different heterocyclic systems such as indoles and benzoisothiazole is feasible. Among the P₁ replacements, benzoisothiazole prevents the formation of GSH conjugate and an in silico analysis of oxidative potentials agreed with the experimental outcome.     

Immunization with Hexon Modified Adenoviral Vectors Integrated with gp83 Epitope Provides Protection against Trypanosoma cruzi Infection

Background

Trypanosoma cruzi is the causative agent of Chagas disease. Chagas disease is an endemic infection that affects over 8 million people throughout Latin America and now has become a global challenge. The current pharmacological treatment of patients is unsuccessful in most cases, highly toxic, and no vaccines are available. The results of inadequate treatment could lead to heart failure resulting in death. Therefore, a vaccine that elicits neutralizing antibodies mediated by cell-mediated immune responses and protection against Chagas disease is necessary.

Methodology/Principal Findings

The “antigen capsid-incorporation” strategy is based upon the display of the T. cruzi epitope as an integral component of the adenovirus'' capsid rather than an encoded transgene. This strategy is predicted to induce a robust humoral immune response to the presented antigen, similar to the response provoked by native Ad capsid proteins. The antigen chosen was T. cruzi gp83, a ligand that is used by T. cruzi to attach to host cells to initiate infection. The gp83 epitope, recognized by the neutralizing MAb 4A4, along with His₆ were incorporated into the Ad serotype 5 (Ad5) vector to generate the vector Ad5-HVR1-gp83-18 (Ad5-gp83). This vector was evaluated by molecular and immunological analyses. Vectors were injected to elicit immune responses against gp83 in mouse models. Our findings indicate that mice immunized with the vector Ad5-gp83 and challenged with a lethal dose of T. cruzi trypomastigotes confer strong immunoprotection with significant reduction in parasitemia levels, increased survival rate and induction of neutralizing antibodies.

Conclusions/Significance

This data demonstrates that immunization with adenovirus containing capsid-incorporated T. cruzi antigen elicits a significant anti-gp83-specific response in two different mouse models, and protection against T. cruzi infection by eliciting neutralizing antibodies mediated by cell-mediated immune responses, as evidenced by the production of several Ig isotypes. Taken together, these novel results show that the recombinant Ad5 presenting T. cruzi gp83 antigen is a useful candidate for the development of a vaccine against Chagas disease.     

METABOLITES OF [3H]ACETATE BOUND TO SYNAPTIC VESICLES ISOLATED FROM RAT CEREBRAL CORTEX

Abstract— Synaptic vesicles were isolated from rat cerebral cortex after an intraventricular injection of [³H]acetate. The labelled substances bound to the synaptic vesicles were released by exposure to acid, separated from the vesicle membranes by Sephadex column chromatography and identified by thin-layer chromatography and thin-layer electrophoresis. The three major peaks of radioactivity were glutamate, glutamine and gamma-aminobutyric acid. Their presence in synaptic vesicles is consistent with the concept of an integration of energy metabolism, membrane regulation and synaptic transmission.     

Natural transformation of Streptococcus crista

Abstract Most brewing strains of Saccharomyces cerevisiae flocculate following growth in beer wort. However, many do not flocculate in laboratory culture media, because their initial pH and buffering capacity do not correspond to the pH range within which these yeasts flocculate. Many, though not all, NewFlo phenotype brewing yeasts flocculate within a narrow pH range only; this is indicative of the existence of more than one NewFlo flocculation phenotype. Such strains may be flocculated by small alterations of pH to within the flocculation range. Induction of flocculation by pH change may be used to separate cells from media at any stage during fermentation.