Galectin-1 promotes immunoglobulin production during plasma cell differentiation.
Galectin-1, a beta-galactoside-binding soluble lectin, has been implicated in regulating immune system homeostasis. We investigated the function of galectin-1 in plasma cell differentiation and found that it is induced in primary murine and human differentiating B cells. B lymphocyte-induced maturation protein-1 (Blimp-1), a master regulator for plasma cell differentiation, was necessary and sufficient to induce galectin-1 expression. Notably, ectopic expression of galectin-1 in mature B cells increased Ig mu-chain transcript levels as well as the overall level of Ig production. This function of galectin-1 was dependent on binding to cell surface glycosylated counter receptors, as a galectin-1 mutant deficient in beta-galactoside binding showed diminished ability to promote Ig production. Extracellular galectin-1 bound more significantly to mature B cells than to plasma cells. Lastly, we found that the sugar compound N-acetyllactosamine blocked the binding of galectin-1 to murine splenic B cells and inhibited their differentiation. Taken together, these data are the first to demonstrate a role for galectin-1 in promoting Ig production during plasma cell differentiation.
Tsai
Chih-Ming
CM
Institute and Department of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.
Chiu
Yi-Kai
YK
Hsu
Tsui-Ling
TL
Lin
I-Ying
IY
Hsieh
Shie-Liang
SL
Lin
Kuo-I
KI
D016475:3T3 Cells; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002454:Cell Differentiation / Q000276:immunology*; D002460:Cell Line; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D005697:Galactosides / Q000378:metabolism; D037483:Galectin 1 / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D010950:Plasma Cells / Q000166:cytology* / Q000378:metabolism; D000074462:Positive Regulatory Domain I-Binding Factor 1; D011485:Protein Binding / Q000276:immunology; D014157:Transcription Factors / Q000502:physiology
D005697:Galactosides; D037483:Galectin 1; D007136:Immunoglobulins; C513258:Prdm1 protein, mouse; D014157:Transcription Factors; C007816:beta-galactoside; D000074462:Positive Regulatory Domain I-Binding Factor 1