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Shao HY, Huang JY, Lin YW, Yu SL, Chitra E, Chang CK, Sung WC, Chong P, Chow YH. Depletion of regulatory T-cells leads to moderate B-cell antigenicity in respiratory syncytial virus infection. Int J Infect Dis 2015; 41:56-64. [PMID: 26555647 DOI: 10.1016/j.ijid.2015.10.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 10/15/2015] [Accepted: 10/31/2015] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVES 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.
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Affiliation(s)
- Hsiao-Yun Shao
- 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
| | - Juo-Yu Huang
- Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
| | - Yi-Wen Lin
- Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
| | - Shu-Ling Yu
- Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
| | - Ebenezer Chitra
- School of Medical Sciences, Division of Human Biology, International Medical University, Kuala Lumpur, Malaysia
| | - Ching-Kun Chang
- 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
| | - Wang-Chou Sung
- Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Room No. R1-7033, No. 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
| | - Pele Chong
- 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
| | - Yen-Hung Chow
- 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.
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Foxp3+ T-regulatory cells require DNA methyltransferase 1 expression to prevent development of lethal autoimmunity. Blood 2013; 121:3631-9. [PMID: 23444399 DOI: 10.1182/blood-2012-08-451765] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Protocols to use Foxp3+ T-regulatory (Treg) cells for cellular therapy, especially postallogeneic stem cell transplantation, are currently being developed and tested by various groups. Inhibitors of DNA methyltransferase (Dnmt) enzymes have been advocated as a means to promote and stabilize Foxp3 expression in Tregs undergoing expansion in vitro before their injection in vivo. We investigated the effects of conditionally deleting two Dnmt enzymes that co-immunoprecipitated with Foxp3 in Treg isolates. Deletion of Dnmt1, but not Dnmt3a, decreased the numbers and function of peripheral Tregs and impaired conversion of conventional T cells into Foxp3+ Tregs under polarizing conditions. Importantly, mice with conditional deletion of Dnmt1 in their Tregs died of autoimmunity by 3 to 4 weeks of age unless they were rescued by perinatal transfer of wild-type Tregs. Conditional Dnmt1 deletion did not affect methylation of CpG sites within Foxp3 but decreased global DNA methylation and altered Treg expression of several hundred pro-inflammatory and other genes. Hence, Dnmt1 is necessary for maintenance of the core gene program underlying Treg development and function, and its deletion within the Treg lineage leads to lethal autoimmunity. These data suggest that caution may be warranted when considering the use of DNMT inhibitors in development of Treg-based cellular therapies.
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