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Swift Intrahepatic Accumulation of Granulocytic Myeloid-Derived Suppressor Cells in a Humanized Mouse Model of Toxic Shock Syndrome.

ABSTRACT: Toxic shock syndrome (TSS) and other superantigen-mediated illnesses are associated with 'systemic' immunosuppression that jeopardizes the host's ability to fight pathogens. Here, we define a novel mechanism of 'local' immunosuppression that may benefit the host. Systemic exposure to staphylococcal enterotoxin B (SEB) rapidly and selectively recruited CD11b(+)Gr-1(high)Ly-6C(+) granulocytic myeloid-derived suppressor cells (MDSCs) to the liver of HLA-DR4 transgenic mice. Hepatic MDSCs inhibited SEB-triggered T cell proliferation in a reactive oxygen species-dependent manner, and ex vivo-generated human MDSCs also similarly attenuated the proliferative response of autologous T cells to SEB. We propose a role for MDSCs in mitigating excessive tissue injury during TSS.

SUBMITTER: Szabo PA

PROVIDER: S-EPMC4878721 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Swift Intrahepatic Accumulation of Granulocytic Myeloid-Derived Suppressor Cells in a Humanized Mouse Model of Toxic Shock Syndrome.

Szabo Peter A PA Goswami Ankur A Memarnejadian Arash A Mallett Christiane L CL Foster Paula J PJ McCormick John K JK Haeryfar S M Mansour SM

The Journal of infectious diseases 20160209 12

Toxic shock syndrome (TSS) and other superantigen-mediated illnesses are associated with 'systemic' immunosuppression that jeopardizes the host's ability to fight pathogens. Here, we define a novel mechanism of 'local' immunosuppression that may benefit the host. Systemic exposure to staphylococcal enterotoxin B (SEB) rapidly and selectively recruited CD11b(+)Gr-1(high)Ly-6C(+) granulocytic myeloid-derived suppressor cells (MDSCs) to the liver of HLA-DR4 transgenic mice. Hepatic MDSCs inhibited ...[more]

PMID: 26908735

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