Purification of interferon from mouse Ehrlich ascites tumor cells

Area of Science:

• Biochemistry
• Immunology
• Virology

Background:

• Interferons are crucial antiviral proteins.
• Understanding interferon production and purification is vital for therapeutic applications.

Purpose of the Study:

• To induce and purify interferon from mouse Ehrlich ascites tumor cells infected with Newcastle disease virus.
• To characterize the purified interferon's molecular weight and specific activity.

Main Methods:

• Interferon induction via Newcastle disease virus.
• Multi-step purification including ammonium sulfate precipitation, various chromatography techniques (carboxymethyl-Sephadex, phosphocellulose, octyl-Sepharose), gel filtration, and isoelectric focusing.
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for molecular weight determination.

Main Results:

• A highly purified interferon product was obtained with a specific activity of 1.6 x 10^9 units/mg protein.
• The interferon-active material exhibited an apparent molecular weight between 25,000 and 35,000 Da.
• Interferon activity co-migrated with a major protein band on SDS-PAGE, distinct from minor, inactive protein bands.

Conclusions:

• Newcastle disease virus is an effective inducer of mouse interferon.
• A robust purification strategy was established for mouse interferon.
• The characterized interferon possesses significant specific activity and a defined molecular weight range.