A method for preparing IgG F(ab')2 fragments using small amounts of serum

Area of Science:

• Immunology
• Biochemistry
• Protein Chemistry

Background:

• Antibody fragments are crucial in various diagnostic and therapeutic applications.
• Existing methods for isolating antibody F(ab")2 fragments are often complex and yield low recovery rates.
• There is a need for more efficient and accessible techniques for antibody fragment isolation.

Purpose of the Study:

• To develop an improved method for isolating functionally active antibody F(ab")2 fragments.
• To reduce the number of manipulations and serum volume required for fragment isolation.
• To enhance the yield and purity of isolated antibody F(ab")2 fragments.

Main Methods:

• Pepsin digestion of the whole globulin fraction precipitated from serum.
• Chromatographic separation using Sephadex G-150.
• Analysis of isolated fragments using immunodiffusion and radioimmunoassays.

Main Results:

• A novel method was developed requiring fewer manipulations and less serum.
• Chromatography yielded two peaks; Peak II contained purified immunoglobulin F(ab")2 fragments.
• Isolated fragments showed less than 10% contamination by non-immunoglobulin proteins.
• Recovery rates of total serum IgG F(ab")2 fragments exceeded 90%, significantly higher than traditional methods (20-25%).

Conclusions:

• The developed method provides a more efficient and effective means of isolating antibody F(ab")2 fragments.
• This technique offers higher yields and purity, making it suitable for various applications.
• The simplified protocol and reduced serum requirement enhance the accessibility of antibody fragment isolation.