Synthetic Peptides Mimic gp75 from Paracoccidioides brasiliensis in the Diagnosis of Paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease, endemic in Latin America, caused by the thermal dimorphic fungus Paracoccidioides brasiliensis. Although some fungal antigens have already been characterized and used for serological diagnosis, cross-reactions have been frequently observed. Thus, the examination of fungal forms in clinical specimens or isolation of P. brasiliensis by culture is still the most frequent method for the diagnosis of this mycosis. In this study, a random peptide phage display library was used to select mimotopes of P. brasiliensis, which were employed as antigens in an indirect enzyme-linked immunosorbent assay. The protective monoclonal antibody against experimental PCM (anti-gp75) was used as molecular target to screen a phage display library. That approach led to a synthetic peptide named P2, which was synthesized and tested against PCM patients’ sera to check whether it was recognized. There was significant recognition of P2 by sera of untreated PCM patients when compared with normal human sera. Sera from treated PCM group, patients with other mycosis or co-infected with HIV had much lower recognition of P2 than untreated patient group. The test showed a sensitivity of 100 and 94.59% of specificity in relation to human sera control. These data indicate a potential use of P2 as diagnostic tool in PCM. Its application for serological diagnosis of PCM may contribute to the development and standardization of simpler, faster and highly reproducible immunodiagnostic tests at low cost

Mono-dispersed Functional Polymeric Nanocapsules with Multi-lacuna via Soapless Microemulsion Polymerization with Spindle-like α-Fe2O3Nanoparticles as Templates

The mono-dispersed crosslinked polymeric multi-lacuna nanocapsules (CP(St–OA) nanocapsules) about 40 nm with carboxylic groups on their inner and outer surfaces were fabricated in the present work. The small conglomerations of the oleic acid modified spindle-like α-Fe2O3nanoparticles (OA–Fe2O3) were encapsulated in the facile microemulsion polymerization with styrene (St) as monomer and divinyl benzene (DVB) as crosslinker. Then the templates, small conglomerations of OA–Fe2O3, were etched with HCl in tetrahydrofuran (THF). The surface carboxylic groups of the crosslinked polymeric multi-lacuna nanocapsules were validated by the Zeta potential analysis

Pooled extracellular receptor-ligand interaction screening using CRISPR activation.

Extracellular interactions between cell surface receptors are necessary for signaling and adhesion but identifying them remains technically challenging. We describe a cell-based genome-wide approach employing CRISPR activation to identify receptors for a defined ligand. We show receptors for high-affinity antibodies and low-affinity ligands can be unambiguously identified when used in pools or as individual binding probes. We apply this technique to identify ligands for the adhesion G-protein-coupled receptors and show that the Nogo myelin-associated inhibitory proteins are ligands for ADGRB1. This method will enable extracellular receptor-ligand identification on a genome-wide scale