Publication Date:
2012-05-05
Description:
Germinal centers (GCs) generate memory B and plasma cells, which are essential for long-lived humoral immunity. GC B cells with high-affinity B cell receptors (BCRs) are selectively expanded. To enable this selection, BCRs of such cells are thought to signal differently from those with lower affinity. We show that, surprisingly, most proliferating GC B cells did not demonstrate active BCR signaling. Rather, spontaneous and induced signaling was limited by increased phosphatase activity. Accordingly, both SH2 domain-containing phosphatase-1 (SHP-1) and SH2 domain-containing inositol 5 phosphatase were hyperphosphorylated in GC cells and remained colocalized with BCRs after ligation. Furthermore, SHP-1 was required for GC maintenance. Intriguingly, GC B cells in the cell-cycle G(2) period regained responsiveness to BCR stimulation. These data have implications for how higher-affinity B cells are selected in the GC.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777391/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777391/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Khalil, Ashraf M -- Cambier, John C -- Shlomchik, Mark J -- AI43603/AI/NIAID NIH HHS/ -- AR44077/AR/NIAMS NIH HHS/ -- R01 AI043603/AI/NIAID NIH HHS/ -- R01 AR044077/AR/NIAMS NIH HHS/ -- New York, N.Y. -- Science. 2012 Jun 1;336(6085):1178-81. doi: 10.1126/science.1213368. Epub 2012 May 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06520, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22555432" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Antibody Affinity
;
Antigen Presentation
;
Antigens/immunology
;
Antigens, CD79/metabolism
;
B-Lymphocytes/enzymology/*immunology/metabolism
;
Calcium/metabolism
;
Cell Cycle
;
Down-Regulation
;
Germinal Center/cytology/*immunology
;
Intracellular Signaling Peptides and Proteins/metabolism
;
Lymphocyte Activation
;
Mice
;
Mice, Inbred BALB C
;
Mice, Transgenic
;
Models, Immunological
;
Phosphoric Monoester Hydrolases/metabolism
;
Phosphorylation
;
Protein Tyrosine Phosphatase, Non-Receptor Type 6/*metabolism
;
Protein-Tyrosine Kinases/metabolism
;
Receptors, Antigen, B-Cell/*immunology/*metabolism
;
Signal Transduction
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
