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Updated: Sep 30, 2025
08:58
Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
Published on: July 5, 2018
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Coordinated changes in glycosylation regulate the germinal center through CD22.
Jhon R Enterina1, Susmita Sarkar2, Laura Streith1
1Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
Cell Reports
|March 16, 2022
Summary
Glycan remodeling in germinal centers (GCs) is crucial for B cell survival and antibody maturation. Downregulating CD22 ligands on GC B cells prevents excessive apoptosis and ensures proper B cell development and antibody quality.
Area of Science:
- Immunology
- Glycobiology
Background:
- Germinal centers (GCs) are vital sites for adaptive immune responses, specifically antibody affinity maturation.
- GC B cells exhibit distinct cell surface glycosylation patterns compared to naive B cells, but their functional significance remains unclear.
- The GL7 antibody, used to detect GCs, recognizes a downregulation of CD22 ligands on GC B cells.
Purpose of the Study:
- To investigate the functional role of CD22 ligand downregulation in germinal center B cell maintenance and function.
- To determine if altered glycosylation impacts B cell survival, antibody maturation, and output of memory B cells and plasma cells.
Main Methods:
- Generation of a novel mouse model maintaining CD22 ligands on germinal center B cells.
- Assessment of B cell apoptosis, memory B cell and plasma cell output, and antibody affinity maturation in the generated mouse model.
Main Results:
- Sustained expression of CD22 ligands on GC B cells leads to increased apoptosis.
- Reduced output of memory B cells and plasma cells was observed in the presence of sustained CD22 ligands.
- Antibody affinity maturation was delayed when CD22 ligands were not downregulated on GC B cells.
- These defects were confirmed to be CD22-dependent.
Conclusions:
- Glycan remodeling, specifically the downregulation of CD22 ligands, is critical for the survival and function of B cells within germinal centers.
- The downregulation of CD22 ligands on B cells is essential for efficient antibody affinity maturation and the generation of high-quality antibody responses.
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