CD8+CD122+ regulatory T cells recognize activated T cells via conventional MHC class I–αβTCR interaction and become IL-10-producing active regulatory cells

M Rifa'i, Z Shi, SY Zhang, YH Lee, H Shiku… - International …, 2008 - academic.oup.com
M Rifa'i, Z Shi, SY Zhang, YH Lee, H Shiku, K Isobe, H Suzuki
International immunology, 2008academic.oup.com
Abstract CD8+ CD122+ regulatory T cells (CD8+ CD122+ Treg) are naturally occurring Treg
that effectively suppress the proliferation and IFN-γ production of both CD8+ and CD4+
target cells. This study investigated the molecular mechanisms of the recognition of target
cells by CD8+ CD122+ Treg using an in vitro culture system that reconstitutes the regulatory
action of these cells. Naive CD8+ CD122+ Treg co-cultured with pre-activated T cells
became active Treg that produced IL-10 and suppressed IFN-γ production from the target T …
Abstract
CD8+CD122+ regulatory T cells (CD8+CD122+ Treg) are naturally occurring Treg that effectively suppress the proliferation and IFN-γ production of both CD8+ and CD4+ target cells. This study investigated the molecular mechanisms of the recognition of target cells by CD8+CD122+ Treg using an in vitro culture system that reconstitutes the regulatory action of these cells. Naive CD8+CD122+ Treg co-cultured with pre-activated T cells became active Treg that produced IL-10 and suppressed IFN-γ production from the target T cells. CD8+CD122+ Treg effectively suppressed the IFN-γ production of the target cells of syngeneic mouse strains but not of allogeneic mouse strains with incompatible MHC. By using MHC-congeneic mouse strains, MHC-restricted suppression by CD8+CD122+ Treg was further confirmed. The blockade of cell surface molecules either on the Treg or on the target cells by specific blocking antibodies indicated that H-2K, H-2D, αβTCR and CD8 were involved in the regulatory action but I-A and Qa-1 were not. These results indicate that CD8+CD122+ Treg recognize already-activated T cells via the interaction of conventional MHC class I–αβTCR and become active regulatory cells that produce IL-10 and suppress the target cells.
Oxford University Press