title: Mature follicular dendritic cell networks depend on expression of lymphotoxin beta receptor by radioresistant stromal cells and of lymphotoxin beta and tumor necrosis factor by B cells.
abstract: The formation of germinal centers (GCs) represents a crucial step in the humoral immune response. Recent studies using gene-targeted mice have revealed that the cytokines tumor necrosis factor (TNF), lymphotoxin (LT) alpha, and LTbeta, as well as their receptors TNF receptor p55 (TNFRp55) and LTbetaR play essential roles in the development of GCs. To establish in which cell types expression of LTbetaR, LTbeta, and TNF is required for GC formation, LTbetaR-/-, LTbeta-/-, TNF-/-, B cell-deficient (BCR-/-), and wild-type mice were used to generate reciprocal or mixed bone marrow (BM) chimeric mice. GCs, herein defined as peanut agglutinin-binding (PNA+) clusters of centroblasts/centrocytes in association with follicular dendritic cell (FDC) networks, were not detectable in LTbetaR-/- hosts after transfer of wild-type BM. In contrast, the GC reaction was restored in LTbeta-/- hosts reconstituted with either wild-type or LTbetaR-/- BM. In BCR-/- recipients reconstituted with compound LTbeta-/-/BCR-/- or TNF-/-/BCR-/- BM grafts, PNA+ cell clusters formed in splenic follicles, but associated FDC networks were strongly reduced or absent. Thus, development of splenic FDC networks depends on expression of LTbeta and TNF by B lymphocytes and LTbetaR by radioresistant stromal cells.
authors.affiliation: Institute of Medical Microbiology, Immunology and Hygiene, Technical University of Munich, D-81675 Munich, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Endres
authors.forename: M B
authors.initials: MB
authors.lastname: Alimzhanov
authors.forename: T
authors.initials: T
authors.lastname: Plitz
authors.forename: A
authors.initials: A
authors.lastname: Fütterer
authors.forename: M H
authors.initials: MH
authors.lastname: Kosco-Vilbois
authors.forename: S A
authors.initials: SA
authors.lastname: Nedospasov
authors.forename: K
authors.initials: K
authors.lastname: Rajewsky
authors.forename: K
authors.initials: K
authors.lastname: Pfeffer
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism*; D016026:Bone Marrow Transplantation; D003713:Dendritic Cells / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D018858:Germinal Center / Q000378:metabolism; D007150:Immunohistochemistry; D053259:Lymphotoxin beta Receptor; D008233:Lymphotoxin-alpha / Q000378:metabolism*; D053308:Lymphotoxin-beta; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D013154:Spleen / Q000254:growth & development* / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism* / Q000528:radiation effects; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014916:Whole-Body Irradiation
chemical_list: C505887:Ltb protein, mouse; C505699:Ltbr protein, mouse; D053259:Lymphotoxin beta Receptor; D008233:Lymphotoxin-alpha; D053308:Lymphotoxin-beta; D008565:Membrane Proteins; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha