An enzyme-linked immunoadsorbent assay for rat ceruloplasmin

Area of Science:

• Biochemistry
• Immunology
• Animal Science

Background:

• Ceruloplasmin is a key copper-binding protein in blood plasma.
• Understanding ceruloplasmin levels is crucial for studying inflammation and liver function.
• Existing methods for measuring rat ceruloplasmin have limitations.

Purpose of the Study:

• To develop and validate a noncompetitive, colorimetric enzyme-linked immunosorbent assay (ELISA) for quantifying rat ceruloplasmin.
• To measure serum ceruloplasmin levels in control and inflamed rats.
• To assess ceruloplasmin secretion by cultured rat hepatocytes.

Main Methods:

• Developed a sandwich ELISA using immobilized antibodies against rat ceruloplasmin.
• Utilized biotinylated antibodies and a streptavidin-alkaline phosphatase conjugate for detection.
• Established standard curves for ceruloplasmin in the range of 10-50 ng/mL.
• Measured ceruloplasmin in rat serum and hepatocyte culture medium.

Main Results:

• The ELISA demonstrated sensitivity with a significant increase in absorbance (A403) for every 10 ng/mL increase in ceruloplasmin.
• Average serum ceruloplasmin levels were 35 mg/dL in control rats and 87 mg/dL in rats with experimental inflammation.
• Isolated rat liver parenchymal cells secreted approximately 1.6 micrograms of ceruloplasmin per 5 x 10(5) cells over 24 hours.

Conclusions:

• The developed ELISA is a reliable method for measuring rat ceruloplasmin.
• This assay facilitates research into the regulation of ceruloplasmin synthesis and secretion.
• The findings highlight elevated ceruloplasmin levels during inflammation and its secretion by hepatocytes.