Immunotherapy with B cell epitopes ameliorates inflammatory responses in Balb/c mice

Alternaria B Cell Mimotope Immunotherapy Alleviates Allergic Responses in a Mouse Model

Alternaria is a major outdoor allergen. Immunotherapy with Alternaria extracts has been documented to be effective in the sensitized patients. However, Alternaria extracts are notoriously difficult to standardize. Our aim is to screen the B cell mimotopes of Alternaria and to evaluate the therapeutic effects of B cell mimotope peptides on a BALB/c mouse model of Alternaria allergy. After a human sera pool from Alternaria monosensitized patients was established, B cell mimotopes were screened by a phage-displayed random heptamer peptide library that was identified via mixed Alternaria-specific IgE in the sera pool. B cell mimotopes with phage as a carrier were used to perform immunotherapy in an Alternaria allergy mouse model. Serological Ab levels, lung histology, and cytokine profiles were compared in the mimotope immunotherapy group, natural extract immunotherapy group, irrelevant phage control group, Alternaria-sensitized model group, and saline-blank group. Two mimotopes (MISTSRK and QKRNTIT) presented high binding ability with the sera of the Alternaria-allergic patients and mice and, therefore, were selected for immunotherapy in the mouse model. Compared with irrelevant phage control, model, and natural extract immunotherapy group, mimotope immunotherapy group significantly reduced serum IgE levels, inflammatory cells infiltration in the lung tissue, and IL-4 levels in bronchoalveolar lavage fluid, whereas serum IgG1 and IFN-γ levels in bronchoalveolar lavage fluid were increased. Our results indicate that B cell mimotopes of Alternaria alleviates allergic response in a mouse model and have potential as novel therapeutic agents for IgE-mediated Alternaria-allergic diseases.

Novel phytopeptide osmotin mimics preventive effects of adiponectin on vascular inflammation and atherosclerosis

INTRODUCTION

The novel phytohormone, osmotin, has been reported to act like mammalian adiponectin through PHO36/AdipoR1 in various in vitro and in vivo models. However, there have been no reports regarding the precise effects of osmotin on atherosclerosis.

METHODS

We assessed the atheroprotective effects of osmotin on inflammatory molecules in human umbilical vein endothelial cells (HUVECs), human leukemic monocyte (THP-1) adhesion, inflammatory responses, and foam cell formation in THP-1-derived macrophages, and the migration, proliferation, and extracellular matrix expression in human aortic smooth muscle cells (HASMCs). We examined whether 4-week infusion of osmotin could suppress the development of aortic atherosclerotic lesions in apolipoprotein E-deficient (ApoE^-/-) mice.

RESULTS

AdipoR1 was abundantly expressed in HUVECs, HASMCs, THP-1, and derived macrophages. Osmotin suppressed lipopolysaccharide-induced upregulation of tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and E-selectin in HUVECs, and TNF-α-induced THP-1-HUVEC adhesion. In THP-1-derived macrophages, osmotin suppressed the inflammatory M1 phenotype, lipopolysaccharide-induced secretion of interleukin-6 and TNF-α, and oxidized low-density lipoprotein-induced foam cell formation associated with CD36 and acyl-CoA:cholesterol acyltransferase 1 downregulation and ATP-binding cassette transporter A1 upregulation. In HASMCs, osmotin suppressed angiotensin II-induced migration, proliferation, collagen-1 and fibronectin expression, and matrix metalloproteinase-2 activity without inducing apoptosis. Infusion of osmotin into ApoE^-/- mice prevented the development of aortic atherosclerotic lesions with reductions of intraplaque pentraxin-3 expression, fasting plasma glucose, and insulin resistance.

CONCLUSIONS

This study provided the first evidence that osmotin exerts preventive effects on vascular inflammation and atherosclerosis, which may facilitate the development of new therapeutic modalities for combating atherosclerosis and related diseases.

ACTUAL CONCEPTION OF ALLERGEN-SPECIFIC IMMUNOTHERAPY MECHANISMS, POTENTIAL BIOMARKERS OF EFFICACY AND WAYS OF ENHANCEMENT

The article analyzes international position papers on the allergen-specific immunotherapy mechanisms, discusses potential biomarkers for evaluation of ASIT efficacy, as well as the perspectives for ASIT enhancement.

International Consensus on Allergen Immunotherapy II: Mechanisms, standardization, and pharmacoeconomics

This article continues the comprehensive international consensus (ICON) statement on allergen immunotherapy (AIT). The initial article also recently appeared in the Journal. The conclusions below focus on key mechanisms of AIT-triggered tolerance, requirements in allergen standardization, AIT cost-effectiveness, and regulatory guidance. Potential barriers to and facilitators of the use of AIT are described in addition to future directions. International allergy specialists representing the European Academy of Allergy and Clinical Immunology; the American Academy of Allergy, Asthma & Immunology; the American College of Allergy, Asthma and Immunology; and the World Allergy Organization critically reviewed the existing literature and prepared this summary of recommendations for best AIT practice. The authors contributed equally and reached consensus on the statements presented herein.