[FAB immunoglobulin fragments. I. The comparative characteristics of the serological and virus-neutralizing properties of a gamma globulin against tick-borne encephalitis and of the FAB fragments isolated from it].

This research study involves the comparative analysis of antiencephalitis gamma-globulin and Fab-fragments, focusing on their virus-neutralizing activities and serological properties. The Fab-fragments were derived from gamma-globulin using gel-filtration and were found to retain serological activity and exhibit notable virus-neutralizing potential.

Research Overview

• The researchers studied the qualities of antiencephalitis gamma-globulin and Fab-fragments isolated from it by gel-filtration.
• The tick-borne encephalitis virus antibody was sourced from horses and decomposed using papaine into monovalent Fab-fragments.
• The study focused on the complement fixation reaction, suppression test of complement fixation, and Hemagglutination Inhibition Test (HAIT) to assess serological activity.

Fab-fragments’ Serological and Virus-Neutralizing Activity

• The Fab-fragments maintained the serological activity comparable to that of gamma-globulin.
• The fragments exhibited significant virus-neutralizing activity.

Comparison of Virus-Neutralizing Activity

• A logarithmic neutralization index was used to measure the virus-neutralizing activity.
• The average value of the logarithmic neutralization index for the Fab-fragments was 2.65 +/- 0.2, less than the 3.74 +/- 0.38 index for gamma-globulin.
• The disparity in the index indicates a statistically significant difference in virus-neutralizing effectiveness between the gamma-globulin and Fab-fragments, with gamma-globulin having higher effectiveness.