Human IgM+IgD+ B cells, the major B cell subset in the peripheral blood, express Vϰ genes with no or little somatic mutation throughout life
✍ Scribed by Ulf Klein; Ralf Küppers; Klaus Rajewsky
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 606 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0014-2980
No coin nor oath required. For personal study only.
✦ Synopsis
life*
Peripheral blood B cells of a 67-year-old person were separated into IgM+IgD+, IgM+IgD-, and IgM-IgD-subsets, and nucleotide sequences of expressed immunoglobulin light chain variable (V) regions encoded by V,3 and V,4 gene family members were determined from amplified cDNA. V region sequences from IgM+IgD+ cells (the major B cell population in the blood) showed no or little somatic mutation (0.3%), in contrast toV, sequences from IgM+IgD-and IgM-IgD-B cells (2.0% and 3.9%, respectively).This suggests that in the human like in the mouse, and independently of age, somatically mutated memory B cells accumulate in the compartment of IgM-IgD-cells, whereas the IgM+IgD+ subpopulation consists of cells whose antibody repertoire is mainly determined by V region gene rearrangements and N-region insertion, at the molecular 1evel.The somatically mutated IgM+IgD-cells may represent early descendants of IgM+IgD+ cells recruited into the memory cell compartment.