BLC (CXCL13) is expressed by different dendritic cell subsets in vitro and in vivo.
Dendritic cells (DC) attract both T and B lymphocytes to induce an efficient antigen-specific immune response. Recently, it was shown that naïve T cells are attracted to DC by dendritic cell chemokine 1 (DC-CK1, CCL18). The potent B lymphocyte chemoattractant BLC (CXCL13) was previously shown to be essential for homing of lymphocytes into secondary lymphoid organs and for the development of B cell follicles. As the cells that produce BLC are largely unknown and BLC could be a candidate chemokine for the recruitment of B cells to DC, we analyzed different DC subsets for expression of BLC. Here we demonstrate that monocyte-derived DC as well as activated blood DC indeed express and secrete BLC. Interestingly, ligation of the CD40 molecule down-regulated BLC expression in monocyte-derived DC. Staining of tonsilar sections indicated that BLC is expressed by follicular dendritic cells and germinal center dendritic cells (GCDC) in vivo. Real-time quantitative PCR confirmed the expression of BLC in isolated GCDC. Since both B cells and activated T cells express the receptor for BLC, our findings implicate an important role for BLC in establishing the interaction of DC with T cells and B cells. Furthermore, CD40/CD40 ligand interactions could modulate this process by down-regulating the expression of BLC.
Vissers
J L
JL
Department of Tumor Immunology, University Medical Center Nijmegen St. Radboud, The Netherlands. g.adema@dent.kun.nl
Hartgers
F C
FC
Lindhout
E
E
Figdor
C G
CG
Adema
G J
GJ
D019013:CD40 Antigens / Q000378:metabolism; D023201:CD40 Ligand / Q000494:pharmacology; D002454:Cell Differentiation; D002478:Cells, Cultured; D054382:Chemokine CXCL13; D019743:Chemokines, CXC / Q000235:genetics / Q000378:metabolism*; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D020566:Dendritic Cells, Follicular / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D007150:Immunohistochemistry; D009000:Monocytes / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D019013:CD40 Antigens; C110663:CXCL13 protein, human; D054382:Chemokine CXCL13; D019743:Chemokines, CXC; D012333:RNA, Messenger; D023201:CD40 Ligand