B-lymphocyte heterogeneity: ontogenetic development and organ distribution of B-lymphocyte populations defined by their density of surface immunoglobulin.

Open Access
Publisher Website
Google Scholar
Abstract
The density of total Ig [immunogllbulin] and of IgM, IgG1, IgG2 and IgA on the surface of adult murine splenic B [bone marrow-derived] lymphocytes was measured using the technique of rapid flow microfluorometry. The density of total surface Ig and IgM on B lymphocytes derived from adult bone marrow, lymph nodes and Peyer''s patches, and from neonatal spleen was determined. Adult spleen and lymph node B lymphocytes are characterized by the presence of a large population of cells with a low-to-intermediate density of total surface Ig, which is seen as a peak in the fluorescence profiles when these cells are labeled with fluorescein-conjugated (Fl) [goat] anti-Ig. This peak is not detected when neonatal spleen or adult bone marrow are examined; the development of this peak among spleen cells occurs during the first 4 wk of life. Although the characteristic fluorescence intensity peak is not seen when adult spleen cells are labeled with Fl anti-.mu., changes in the density of surface IgM occur during the 1st few wk of life, and are detected as a decrease in the frequency of cells which have relatively large amounts of surface IgM. The differences seen in the fluorescence patterns of adult spleen cells labeled with Fl anti-Ig and Fl anti-.mu. may be due to the appearance of IgD on the surface of mature splenic B lymphocytes. This is supported by the similarity of the fluorescence profiles of adult bone marrow cells stained with Fl anti-.mu., as the latter population of cells is reported to lack surface IgD.