Polarized expression of immunoglobulin, spectrin, and protein kinase C beta II occurs in B cells from normal BALB/c, autoimmune lpr, and anti-ssDNA transgenic, tolerant mice.
The rapid redistribution of B cell surface immunoglobulin to a cap upon cross-linking treatment is a well-described phenomenon, the physiological significance of which is unknown. We describe the observation that splenic B cells from unimmunized normal, autoimmune, and tolerant mice express naturally occurring capped immunoglobulin in the absence of exogenous stimulation. The percentage of capped B cells increases to 20% of B cells by age 16 weeks in the progressive autoimmune lpr mouse. Transgenic, tolerant mice expressing lpr-derived genes for ssDNA-binding antibody also demonstrate a large percentage (35-75%) of immunoglobulin-capped splenic B cells. In these capped B cells, protein kinase C beta II, the cytoskeletal proteins spectrin and ankyrin, and the lipophilic probe diI are enriched beneath the site of the immunoglobulin cap. These data suggest that polarization of surface receptors, signaling molecules, anionic phospholipid domains, and cytoskeletal proteins may be an important part of the B cell immune response in vivo.
Masso-Welch
P A
PA
Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
Black
J D
JD
Erikson
J
J
Repasky
E A
EA
D000818:Animals; D015551:Autoimmunity; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002232:Carbocyanines; D002462:Cell Membrane; D016764:Cell Polarity; D004277:DNA, Single-Stranded / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D005456:Fluorescent Dyes; D015870:Gene Expression; D007108:Immune Tolerance / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains / Q000096:biosynthesis / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000096:biosynthesis / Q000235:genetics; D007136:Immunoglobulins / Q000096:biosynthesis* / Q000235:genetics; D007527:Isoenzymes / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D019463:Mice, Inbred MRL lpr; D008822:Mice, Transgenic; D011493:Protein Kinase C / Q000096:biosynthesis*; D064546:Protein Kinase C beta; D013049:Spectrin / Q000096:biosynthesis*; D013194:Staining and Labeling / Q000379:methods
C035005:3,3'-dihexadecylindocarbocyanine; D002232:Carbocyanines; D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007136:Immunoglobulins; D007527:Isoenzymes; D013049:Spectrin; D011493:Protein Kinase C; D064546:Protein Kinase C beta