Related Experiment Videos
Immunoglobulin gene usage in the human anti-pathogen response
1Department of Medicine, Montreal General Hospital Research Institute, McGill University, Quebec, Canada.
Infectious Agents and Disease
|September 1, 1995
Summary
Human antibody responses to pathogens utilize diverse mechanisms and specific immunoglobulin gene elements, with some showing limited mutation even in IgG forms. This suggests a complex, non-random repertoire generation for combating infections.
Area of Science:
- Immunology
- Molecular Biology
- Pathogen Response
Background:
- Human antibody responses target a limited set of pathogen surface molecules with numerous epitopes.
- Antibody generation involves diverse mechanisms to create a sufficient repertoire against invading pathogens.
Purpose of the Study:
- To investigate the diversity of mechanisms and immunoglobulin gene element usage in human antibody responses to pathogens.
- To analyze the extent of somatic hypermutation in antibodies targeting different pathogens.
Main Methods:
- Analysis of human monoclonal antibodies against various pathogens.
- Examination of immunoglobulin gene element usage (heavy and light chains).
- Quantification of somatic hypermutation levels in different antibody classes (IgM, IgG).
Main Results:
- Specific immunoglobulin gene elements are preferentially used in antibody responses, indicating non-random selection.
- The immune response to Haemophilus influenzae polysaccharide is narrow, while cytomegalovirus protein response is broader.
- A significant percentage of IgG antibodies exhibited low somatic mutation levels, similar to un-matured IgM.
Conclusions:
- Human antibody repertoires against pathogens are shaped by specific, non-random selection of immunoglobulin gene elements.
- The level of somatic hypermutation in antibodies against pathogens can be unexpectedly low, resembling the adult IgM repertoire.
- Similarities exist between antibody responses to pathogens and autoantibodies.