Skip to main content
ARS Home » Research » Publications at this Location » Publication #79747
Title: THE INFLUENCE OF IMMUNIZATION ON THE PULMONARY INFLAMMATORY RESPONSE OF RABBITS INDUCED BY PASTEURELLA HAEMOLYTICA A1 LIPOPOLYSACCHARIDE

Author
item RAMIREZ, ROMERO - FMZ UNAL MONTERREY MEX
item Brogden, Kim
item Cutlip, Randall

Submitted to: International Virtual Conference on Infectious Diseases of Animals
Publication Type: Abstract Only
Publication Acceptance Date: 4/20/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Immune complex formation has long been thought to be involved in the pathogenesis of pneumonic pasteurellosis. However, only a few studies have examined this mechanism and no suitable models exist. We wanted to establish a rabbit model to study immune-medited damage in respiratory tissue caused by LPS. Severe lesions were induced by IT injections of LPS (50 micro g) in rabbits immunized with a P. haemolytica whole cell bacteri in FIA (LPS PHA titer 1:320-1:2560) and included perivascular edema and PMN leukocyte infiltration of subintima with degeneration and necrosis of media. Smaller vessels were occluded by PMN leukocytes in various stages of degranulation. PMN leukocytes counts in BAL fluid were high (p greater than 0.05). Lesions were also induced by IT injection of LPS (50 micro g) into rabbits immunized with FIA alone and included moderate to severe congestion, interstitial edema, alveolar serofibrinous exudation and PMN leukocyte infiltration. PMN leukocytes were also present in BAL fluids. Rabbits immunized with FIA and challenged with saline and rabbits immunized with BSA in FIA and challenged with BSA were included as negative and positive control groups. Cutaneous lesions were also induced by ID injection of LPS in bacterin-vaccinated rabbits and ID injection of BSA in rabbits vaccinated with BSA. Overall, lesions induced in vaccinated rabbits by LPS were more severe than those seen in nonvaccinated rabbits and were similar to those seen in natural cases of bovine pneumonic pasteurellosis. This model may help delineate mechanisms involved in the pathogenesis of pneumonic pasteurellosis in immunized animals.