Polymerization of human transcortin in plasma

Area of Science:

• Biochemistry
• Immunology

Background:

• Transcortin is a key protein in corticosteroid transport.
• Understanding transcortin's behavior in plasma is crucial for corticosteroid regulation studies.

Purpose of the Study:

• To identify and characterize polymers of native transcortin in plasma.
• To investigate the reversibility and disaggregation of transcortin polymers.

Main Methods:

• Radial immunodiffusion using antiserum against purified transcortin.
• Spectrophotometric scans to monitor polymerization kinetics.
• Testing disaggregation agents like sodium dodecyl sulphate and dithiothreitol.

Main Results:

• Polymers of native transcortin were identified in plasma via precipitin bands.
• Polymer size diminished upon dilution, indicating reversibility.
• Purified transcortin also showed dilution-reversible polymerization.
• Sodium dodecyl sulphate and dithiothreitol induced disaggregation, but cortisol did not.

Conclusions:

• Native transcortin can form reversible polymers in plasma.
• The polymerization process is influenced by dilution and specific chemical agents.
• Cortisol does not appear to directly disaggregate transcortin polymers.