A phenotypic study of B lymphocyte subpopulations in human bone marrow.
The regulatory mechanisms that monitor the size of the peripheral B cell pool and determine cell death or survival are poorly understood. In rodents B lymphopoiesis is maintained at a high rate throughout adult life, and under resting conditions there is little recruitment into the long-lived peripheral pool; it therefore follows that most newly formed B lymphocytes have a very short lifespan. The maturation stages of B lymphopoiesis in humans and in experimental mammals appear to be similar. We have determined the phenotype of sIgM- and sIgD-expressing cells from normal adult human bone-marrow and peripheral blood by dual immunofluorescence with an extensive panel of monoclonal antibodies representative of major B cell clusters, in order to identify antigenic differences that may play a regulatory role. Antibodies of the CD21, CD22 and CD9 clusters, the unclustered restricted B antibody 7-F-7 and anti-IgD were reactive with different proportions of sIgM+ cells in blood and bone marrow; 29.5% (range 5-60%) of sIgM+ cells in marrow were sIgD- and most of these cells were also CD21- and CD22-, thus defining a unique marrow population. However, newly formed and mature re-circulating cells comprising the sIgM+sIgD+ population could not be distinguished by the panel of antibodies.
Department of Immunology, Medical School, Birmingham, UK.
M R
MR
Chapple
I C
IC
MacLennan
G D
GD
Johnson
D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D005455:Fluorescent Antibody Technique; D006801:Humans; D007072:Immunoglobulin D / Q000378:metabolism; D007132:Immunoglobulin Isotypes / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism; D013154:Spleen / Q000166:cytology / Q000276:immunology
D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D007072:Immunoglobulin D; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell