Novel Peptide Nanoparticle Biased Antagonist of CCR3 Blocks Eosinophil Recruitment and Airway Hyperresponsiveness

Background—Chemokine signaling through CCR3 is a key regulatory pathway for eosinophil recruitment into tissues associated with allergic inflammation and asthma. To date, none of the CCR3 antagonists have shown efficacy in clinical trials. One reason may be their unbiased mode of inhibition that prevents receptor internalization, leading to drug tolerance. Objective—We sought to develop a novel peptide nanoparticle CCR3 inhibitor (R321) with a biased mode of inhibition that would block G-protein signaling, but enable or promote receptor internalization. Methods—Self-assembly of R321 peptide into nanoparticles and peptide binding to CCR3 were analyzed by dynamic light scattering and NMR. Inhibitory activity on CCR3 signaling was assessed in vitro using flow cytometry, confocal microscopy, and western blot analysis in a CCR3+ eosinophil cell line and blood eosinophils. In vivo effects of R321 were assessed using a triple allergen mouse asthma model. Results—R321 self-assembles into nanoparticles and binds directly to CCR3, altering receptor function. IC50 values for eotaxin-induced chemotaxis of blood eosinophils are in the low nanomolar range. R321 inhibits only the early phase of ERK1/2 activation and not the late phase generally associated with β-arrestin recruitment and receptor endocytosis, promoting CCR3 internalization and degradation. In vivo, R321 effectively blocks eosinophil recruitment into the lungs and airways and prevents airway hyperresponsiveness in a mouse eosinophilic asthma model. Conclusions—R321 is a potent and selective antagonist of the CCR3 signaling cascade. Inhibition through a biased mode of antagonism may hold significant therapeutic promise by eluding the formation of drug tolerance

A Study on Genetic Analysis and Extract Cytotoxicity of Scolopendra subspinipes multilans L. Koch

Objective : The purpose of this study is to investigate nucleotide sequence and extract cytotoxicity of Scolopendrae corpus. The nature and taste of Scolopendrae corpus is hot, Warm and toxic, and the effect of this is dispelling wind, anti-spasmodic action and detoxication so it has been used for C.V.A, facial palsy, sensory disorder at extremities, wounds and arthritis. Methods : Scolopendrae corpus were collected by locality on the market. They were morphologically classified. Their nucleotide sequence was investigated and compared among them. In addition, the water-alcohol extract cytotoxicity of them was studied by MTT-based cytotoxicity assay. Results : It was shown that the each Scolopendrae corpus by locality is almost identical at genetic result and is identified as Scolopendra subspinipes mutilans L. Koch. Nucleotide sequence of Scolopendra subspinipes mutilans L. Koch in this study will help to discriminate other species of Scolopendrae corpus. The water-alcohol extract of Scolopendra subspinipes mutilans L. Koch did not induce cytotoxicity on Hep G2, L929 cell and peritoneal macrophages. Besides, it did not influence nitrite production of peritoneal macrophages. These results can be used as basic data for genetic discrimination with another species of scolopendrae corpus

Enhanced Immunogenicity and Protective Efficacy with the Use of Interleukin-12-Encapsulated Microspheres plus AS01B in Tuberculosis Subunit Vaccination

Tuberculosis subunit vaccines codelivered with interleukin-12 (IL-12)-encapsulated microspheres (IL-12EM) are designed for a sustained release of IL-12 and could induce strong Th1 immune responses specific to Ag85A and ESAT-6. The adjuvant combination of IL-12EM plus AS01B was a more efficient way to induce a sustained Th1 immunity and protection against Mycobacterium tuberculosis

Novel peptide nanoparticle–biased antagonist of CCR3 blocks eosinophil recruitment and airway hyperresponsiveness

Background—Chemokine signaling through CCR3 is a key regulatory pathway for eosinophil recruitment into tissues associated with allergic inflammation and asthma. To date, none of the CCR3 antagonists have shown efficacy in clinical trials. One reason may be their unbiased mode of inhibition that prevents receptor internalization, leading to drug tolerance. Objective—We sought to develop a novel peptide nanoparticle CCR3 inhibitor (R321) with a biased mode of inhibition that would block G-protein signaling, but enable or promote receptor internalization. Methods—Self-assembly of R321 peptide into nanoparticles and peptide binding to CCR3 were analyzed by dynamic light scattering and NMR. Inhibitory activity on CCR3 signaling was assessed in vitro using flow cytometry, confocal microscopy, and western blot analysis in a CCR3+ eosinophil cell line and blood eosinophils. In vivo effects of R321 were assessed using a triple allergen mouse asthma model. Results—R321 self-assembles into nanoparticles and binds directly to CCR3, altering receptor function. IC50 values for eotaxin-induced chemotaxis of blood eosinophils are in the low nanomolar range. R321 inhibits only the early phase of ERK1/2 activation and not the late phase generally associated with β-arrestin recruitment and receptor endocytosis, promoting CCR3 internalization and degradation. In vivo, R321 effectively blocks eosinophil recruitment into the lungs and airways and prevents airway hyperresponsiveness in a mouse eosinophilic asthma model. Conclusions—R321 is a potent and selective antagonist of the CCR3 signaling cascade. Inhibition through a biased mode of antagonism may hold significant therapeutic promise by eluding the formation of drug tolerance