Peritoneal Ly‐1 B cells: Genetic control, autoantibody production, increased lambda light chain expression

Abstract

Previous studies demonstrate that Ly-1 B cells and their progenitors are clearly detectable in peritoneum in normal mice. In this publication, we show (a) that peritoneal Ly-1 B cells resemble splenic Ly-1 B cells with respect to surface marker expression and functional activity (autoantibody production); (b) that Ly-1 B frequencies in peritoneum are considerably higher than in spleen; and (c) that genetic mechanisms reduce peritoneal Ly-1 B frequencies to minimal levels in SJL-related mice and to below detectability in CBA/N and other mice with the X-linked immunodeficiency (Xid). In addition, we show that that peritoneal (and perhaps splenic) Ly-1 B populations demonstrate an unique bias in immunoglobulin commitment. That is, they are selectively enriched for cells that express IgM heavy chains in association with lambda light chains. Thus, as a whole, evidence presented here defines the peritoneum as a tightly regulated lymphocyte compartment that normally houses a large population of mature Ly-1 B cells with distinctive functional properties.

Human Hematopoietic Stem/Progenitor Cells Generate CD5+B Lymphoid Cells in NOD/SCID Mice

“…Other features shared by the CD5 + B cells in the hu/mu chimeras and the CD5 + B cells described in the literature are coexpression of HLA-DR [54], sIgM and sIgD [54], CD9 [67], CD19 [59], CD20 [59], and CD43 [68,69]. The low expression of λ light chains in conjunction with sIgM observed in one chimera (Table 2) may be consistent with the observation that murine peritoneal CD5 + B cells are selectively enriched for cells expressing both sIgM and λ light chains [70], but this requires more extensive investigation in larger numbers of hu/mu chimeras. CD11b was not detected in the single chimera whose CD5 + B cells we tested, whereas murine CD11b (Mac-1) is expressed on murine peritoneal but not splenic CD5 + B cells [54].…”

At the crossroads between tolerance and aggression

“…[4][5][6]13 Using adoptive transfer experiments, it was demonstrated that injection of mature B-1 B cells into congenic recipients led to repopulation of the B-1 B cell compartment but not to "conventional" CD5-B cells (B-2 B cells). 5 Reciprocally, transfer of adult bone marrow resulted in the generation of B-2 B cells but very few B-1 B cells.…”

Polyreactive Binding of Antibodies Generated by Polyclonal B Cell Activation. I. Polyreactivity Could be Caused by Differential Glycosylation of Immunoglobulins

“…Specific and polyreactive Abs could be two parallel repertoires [3,[29][30][31][32]. However, it is equally possible that co-or posttranslational modifications of Igs obtained from the same rearrangement are responsible for the generation of monospecific or polyreactive Abs.…”