title: Aberrant expression of BAFF by B lymphocytes infiltrating the salivary glands of patients with primary Sjögren's syndrome.
abstract: OBJECTIVE
  To identify the cells that produce BAFF in the salivary glands of patients with primary Sjögren's syndrome (SS), and to analyze BAFF receptor expression by local T and B lymphocytes.
  
  
  METHODS
  We used 3 methods to identify the source of BAFF: in situ hybridization of the transcripts for BAFF combined with staining of membrane markers, regular and real-time reverse transcription-polymerase chain reaction (RT-PCR) of cultured epithelial cells, and RT-PCR of sorted single-cell T and B lymphocytes eluted from salivary glands. Cells expressing TACI, BCMA, and B lymphocyte stimulator receptor 3 (BR-3) were disclosed by combining each specific staining of the receptors with each specific staining of the cells. The function of BAFF generated by epithelial cells on B lymphocytes was determined in short-term cocultures.
  
  
  RESULTS
  Transcripts for BAFF were seen in epithelial cells and infiltrating T lymphocytes and, for the first time, were detected in local B cells. It is interesting that BR-3 was present on these B cells but not on T cells. In contrast, TACI and, to a lesser degree, BCMA were observed on transitional B lymphocytes, whereas T lymphocytes were devoid of receptors for BAFF. Furthermore, this cytokine was shown to be functional, in that epithelial cell-bound BAFF extended the survival of normal B cells, but cell-free BAFF released in the supernatants did not.
  
  
  CONCLUSIONS
  These experiments establish that in primary SS, BAFF is produced not only by epithelial cells and T cells but also by B cells. The expression of receptors for BAFF would thus allow these receptors to participate in an autocrine pattern of self-stimulation.
authors: Laboratory of Immunology, Brest University Medical School Hospital, Brest, France.
authors: Capucine
authors: C
authors: Daridon
authors: Valérie
authors: V
authors: Devauchelle
authors: Pascal
authors: P
authors: Hutin
authors: Rozenn
authors: R
authors: Le Berre
authors: Christine
authors: C
authors: Martins-Carvalho
authors: Boutahar
authors: B
authors: Bendaoud
authors: Maryvonne
authors: M
authors: Dueymes
authors: Alain
authors: A
authors: Saraux
authors: Pierre
authors: P
authors: Youinou
authors: Jacques-Olivier
authors: JO
authors: Pers
mesh_terms: D000328:Adult; D000368:Aged; D053264:B-Cell Activating Factor / Q000096:biosynthesis* / Q000235:genetics; D053301:B-Cell Maturation Antigen / Q000235:genetics / Q000378:metabolism; D001402:B-Lymphocytes / Q000378:metabolism* / Q000473:pathology; D015415:Biomarkers / Q000378:metabolism; D018920:Coculture Techniques; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000033:anatomy & histology / Q000378:metabolism* / Q000473:pathology; D012859:Sjogren's Syndrome / Q000378:metabolism* / Q000473:pathology; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology; D053303:Transmembrane Activator and CAML Interactor Protein / Q000235:genetics / Q000378:metabolism; D020298:U937 Cells
chemical_list: D053264:B-Cell Activating Factor; D053301:B-Cell Maturation Antigen; C465019:BR-3 protein, human; D015415:Biomarkers; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C108467:TNFRSF13B protein, human; C086966:TNFRSF17 protein, human; C505719:TNFSF13B protein, human; D053303:Transmembrane Activator and CAML Interactor Protein