title: B lymphocytes that migrate to tuberculous pleural fluid via the SDF-1/CXCR4 axis actively respond to antigens specific for Mycobacterium tuberculosis.
abstract: B-cell biology has been largely uncharacterized in the field of tuberculosis (TB). In this study, we investigated the immunophenotypical and functional characteristics of B cells obtained from the pleural fluid (PF) and peripheral blood of patients with tuberculous pleuritis (TP). Our results indicated that the total numbers of B cells, CD27(+)  memory B cells and plasmablasts were clearly lower in the PF than in peripheral blood. Furthermore, we found significantly higher expression of CXCR4 on B cells in the PF, and a chemotaxis assay showed that B cells in the PF were more responsive to stromal cell-derived factor-1 (SDF-1) than B cells from peripheral blood. In addition, SDF-1 levels in PF were remarkably high compared with SDF-1 levels in plasma, suggesting that the SDF-1/CXCR4 axis might facilitate the migration of circulating B cells into tuberculous pleural space. Importantly, we observed that significantly more antibodies were produced by B cells in the PF following stimulation with BCG, early secretory antigenic target (ESAT-6)/culture filtrate protein-10 (CFP-10) or ESAT-6 protein. Collectively, these data demonstrate that Mycobacterium tuberculosis-specific B cells exist at local sites of infection in TP patients and this localization might influence the immune response to M. tuberculosis.
authors.affiliation: Institute of Immunology, Zhongshan School of Medicine, Key Laboratory of Tropical Disease Control Research of Ministry of Education, Sun Yat-sen University, Guangzhou, PR China.
authors.forename: Lian
authors.initials: L
authors.lastname: Feng
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Liu
authors.forename: Dan
authors.initials: D
authors.lastname: Qiao
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Fu
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Suihua
authors.initials: S
authors.lastname: Lao
authors.forename: Changyou
authors.initials: C
authors.lastname: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000276:immunology* / Q000378:metabolism; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D002469:Cell Separation; D054377:Chemokine CXCL12 / Q000276:immunology* / Q000378:metabolism; D002634:Chemotaxis, Leukocyte / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D019718:Receptors, CXCR4 / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction / Q000276:immunology; D014396:Tuberculosis, Pleural / Q000276:immunology*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; C515255:CXCL12 protein, human; C527276:CXCR4 protein, human; D054377:Chemokine CXCL12; D019718:Receptors, CXCR4