Homeostatic and functional analysis of mature B cells in λ5-deficient mice

• Published in: Immunology letters Vol. 101; no. 2; pp. 173 - 184
• Main Authors: Harfst, Eva, Andersson, Jan, Grawunder, Ulf, Ceredig, Rod, Rolink, Antonius G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.11.2005
• Subjects: B1 cells; Follicular B cells; Marginal-zone B cells; SL chain; BAFF; SSC; RU; FOB cells; Marginal-zone B cells; PEC; TD; NIP; TI; FSC; IgH chain; PI; preBCR; λ5; B1 cells; BrdU; MZB cells; Follicular B cells
• ISSN: 0165-2478; 1879-0542
• DOI: 10.1016/j.imlet.2005.05.013

The peripheral B-cell pool is in dynamic equilibrium and is controlled by a variety of factors. The rate of generation of B cells can influence both the composition and size of the peripheral B-cell compartment. Mice deficient for λ5 gene expression have a block in early B-cell development leading to a markedly reduced number of peripheral B cells. To address the question of how this early developmental block influences the composition of the B-cell pool, we have analyzed mature B-cell subpopulations in λ5-deficient mice. In analogy with other situations of B lymphopenia, the proportion was increased but not the absolute number of marginal-zone B cells, whereas those of follicular B cells were decreased. Immunohistology revealed that B-cell follicles were smaller in overall size and contained a prominent B-cell replete marginal zone. BrdU labelling kinetics showed slower turnover of follicular as well as of marginal-zone B cells. Functionally, λ5 −/− mice were able to mount not only primary but also secondary thymus-dependent as well as thymus-independent responses, albeit mostly at reduced levels.