Human transfer factor: fractionation by electrofocusing and high pressure, reverse phase chromatography

Area of Science:

• Immunology
• Biochemistry
• Chromatography

Background:

• Human transfer factor (HTF) is a complex biological material known for its immune-modulating properties.
• Previous studies utilized Sephadex G-25 chromatography to isolate biologically active HTF fractions, specifically fraction III.

Purpose of the Study:

• To further resolve the biologically active Sephadex G-25 fraction III of human transfer factor into distinct components.
• To characterize the immunological and biochemical properties of these sub-fractions.

Main Methods:

• Exclusion chromatography (Sephadex G-25) to obtain fraction III.
• Further fractionation of fraction III using electrofocusing and high-pressure reverse-phase chromatography.
• Assay of transferred donor reactivities (to PPD or KLH) and dermal reactions in recipients.

Main Results:

• Fraction III was separated into two sub-fractions: IIIa and IIIb.
• Fraction IIIa successfully transferred donor immune reactivities (to PPD or KLH) to recipients.
• Fraction IIIb failed to transfer donor reactivities but induced antigen-independent and antigen-dependent dermal reactions.
• Biochemical analysis revealed distinct UV-absorbing component profiles for IIIa and IIIb.
• The major component of IIIa, isolated via preparative electrofocusing, exhibited an isoelectric point of 1.6 and transferred KLH reactivity.

Conclusions:

• Human transfer factor fraction III comprises at least two distinct components with differing biological activities.
• Fraction IIIa contains the component(s) responsible for transferring specific immune reactivities.
• Fraction IIIb possesses components that elicit dermal reactions but do not transfer specific donor reactivities.