A product of the C4B locus lacking hemolytic activity

Area of Science:

• Immunogenetics
• Complement system biology

Background:

• Complement component 4B (C4B) is a crucial part of the complement system.
• C4B polymorphism influences immune responses and disease susceptibility.
• Understanding C4B variants is essential for immunogenetic studies.

Purpose of the Study:

• To characterize a novel C4B allotype identified in the Japanese population.
• To investigate the functional activity of this newly identified C4B variant.

Main Methods:

• Utilized murine monoclonal antibodies specific for the C4d region of C4B to define the allotype.
• Performed hemolytic assays to assess the functional activity of the C4B variant.

Main Results:

• An unusual C4B allotype, designated C4B 4I, was identified.
• This C4B 4I variant was recognized by a specific monoclonal antibody.
• Hemolytic assays demonstrated that C4B 4I is hemolytically inactive.

Conclusions:

• The C4B 4I allotype represents a functionally deficient variant within the C4B locus.
• This finding contributes to the understanding of C4B polymorphism and its functional implications.