The Ovalbumin: A Potent Allergen for Inducing Systemic Inflammatory Response Causing Asthma

Abstract

Background: Asthma is a chronic inflammatory disease of the airways characterized by airway hyperresponsiveness, inflammation, and remodeling. The present study aims to investigate the histopathological changes observed in the lungs of Wistar albino rats sensitized and challenged with ovalbumin (OVA), providing insights into the effects at the tissue level and potential mechanisms underlying these conditions.

Methods: Wistar albino rats were sensitized with intraperitoneal injections of OVA combined with aluminum hydroxide and subsequently challenged with OVA aerosols. After the OVA challenge, rats were euthanized, and blood and lung tissues were collected. IgE, total, and differential leukocytes were measured in the blood samples. Lung tissues were fixed in 10% formalin and thin sections of the paraffin-embedded lungs were prepared and stained with hematoxylin and eosin to assess the histopathological alterations.

Results: Histopathological analysis of lung tissues revealed marked inflammatory cell infiltration, predominantly eosinophils, and lymphocytes, in the peri-bronchial and peri-vascular regions. Interstitial edema was also observed. Vascular changes, such as increased permeability and dilation, were noted. The study demonstrates that OVA sensitization and challenge in Wistar albino rats induce significant histopathological changes in the lungs, resembling the pathological features of human asthma. These findings highlight the utility of this model in understanding disease mechanisms and evaluating potential therapeutic interventions for airway inflammatory diseases.