title: Depletion of regulatory T-cells leads to moderate B-cell antigenicity in respiratory syncytial virus infection.
abstract: OBJECTIVE
  The regulation of the immunopathology of respiratory syncytial virus (RSV) by regulatory T-cells (CD4(+)CD25(+)Foxp3(+); Tregs) is not understood.
  
  
  METHODS
  To deduce the same, Tregs were depleted in BALB/c mice by injecting anti-CD25 antibody followed by RSV infection (anti-CD25-RSV mice).
  
  
  RESULTS
  In this model, a decrease in anti-fusion (F) antibody and neutralizing activity, and an increase in anti-nucleocapsid (N) antibody in serum, were seen. Decreased antibody-dependent cell-mediated cytotoxicity (ADCC) activity, increased IgG2a, and an influx of activated CD8(+) T-cells into the lungs were also observed. Co-culture of splenic CD45RA(+) B-cells from RSV-infected normal mice with CD4(+) cells isolated from anti-CD25-RSV mice (B/CD4) increased anti-F antibody secretion. The inclusion of CD25(+) Tregs isolated from isotype Ig-RSV mice into the B/CD4 co-culture substantially enhanced the frequency of anti-F antibody production. However, the same effect was not seen in the co-culture of CD45RA(+) B-cells with dendritic cells (DCs) (B/DCs) or CD8(+) cells (B/CD8) that were obtained from anti-CD25-RSV mice. The transfer of enriched B-cells from anti-CD25-RSV mice into RSV-infected SCID mice increased severe lung inflammation associated with the increased viral load and eosinophil number.
  
  
  CONCLUSIONS
  These results indicate that Tregs modulate B-cell activity, particularly in producing F-specific neutralizing antibodies, to regulate RSV-mediated exacerbated diseases.
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan; Graduate Program of Biotechnology in Medicine, Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Hsiao-Yun
authors.initials: HY
authors.lastname: Shao
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan.
authors.forename: Juo-Yu
authors.initials: JY
authors.lastname: Huang
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan.
authors.forename: Yi-Wen
authors.initials: YW
authors.lastname: Lin
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan.
authors.forename: Shu-Ling
authors.initials: SL
authors.lastname: Yu
authors.affiliation: School of Medical Sciences, Division of Human Biology, International Medical University, Kuala Lumpur, Malaysia.
authors.forename: Ebenezer
authors.initials: E
authors.lastname: Chitra
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan; Graduate School of Life Science, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Ching-Kun
authors.initials: CK
authors.lastname: Chang
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan.
authors.forename: Wang-Chou
authors.initials: WC
authors.lastname: Sung
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan; Graduate Institute of Immunology, China Medical University, Taichung, Taiwan.
authors.forename: Pele
authors.initials: P
authors.lastname: Chong
authors.affiliation: Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan; Graduate Institute of Immunology, China Medical University, Taichung, Taiwan. Electronic address: choeyenh@nhri.org.tw.
authors.forename: Yen-Hung
authors.initials: YH
authors.lastname: Chow
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D001402:B-Lymphocytes / Q000502:physiology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D008168:Lung / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D016513:Mice, SCID; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology* / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000276:immunology; D013154:Spleen / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000502:physiology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral
keywords: Antigenicity; B-cells; Regulatory T-cells; Respiratory syncytial virus