Enzyme-linked immunosorbent assay for detection of antibody to Pseudomonas aeruginosa and measurement of antibody titer in horse serum.

This research study aimed to use an enzyme-linked immunosorbent assay (ELISA) to detect antibodies against Pseudomonas aeruginosa antigens, including endotoxin proteins, protease, and elastase, in horse sera. The data obtained demonstrated changes in immunoglobulin M (IgM) and IgG levels following vaccination and also identified the presence of these antibodies in the sera of newborn foals.

Methodology

• The researchers utilised ELISA, a commonly used biochemical technique, to detect the presence of IgM and IgG antibodies against Pseudomonas aeruginosa – a bacterium known to cause disease in horses – in horse sera.
• In order to label the detected antibodies, the team used horseradish peroxidase-labeled rabbit anti-horse IgM and IgG antibodies. When these antibodies bind to their corresponding antigens, the horseradish peroxidase catalyzes a reaction with 5-Aminosalicylic acid and H2O2, producing a measurable signal.
• Sera from a vaccinated horse, a newborn foal, and 72 healthy racehorses were evaluated for the presence of antibodies against Pseudomonas aeruginosa using both ELISA and a passive hemagglutination procedure.

Findings

• Results from ELISA demonstrated distinct changes in IgM and IgG antibody titers following vaccination. This indicates that the horse’s immune system was responding to the vaccine by producing antibodies against the targeted antigens.
• In the newborn foal, significant quantities of IgM and IgG antibodies were found on the first day following birth. These antibodies presumably came from the mother’s colostrum (the first milk following birth, which is usually rich in antibodies). The ELISA also indicated that the level of antibodies initially decreased after birth and then increased significantly.
• The study further revealed that almost all the tested racehorses had some antibodies against the native endotoxin protein, protease, and elastase of Pseudomonas aeruginosa. This suggests a widespread exposure to this bacterium in the horse population.