Priming of CD4+ T cells by liver sinusoidal endothelial cells induces CD25low forkhead box protein 3- regulatory T cells suppressing autoimmune hepatitis

TY - JOUR

T1 - Priming of CD4+ T cells by liver sinusoidal endothelial cells induces CD25low forkhead box protein 3- regulatory T cells suppressing autoimmune hepatitis

AU - Kruse, Nils

AU - Neumann, Katrin

AU - Schrage, Arnhild

AU - Derkow, Katja

AU - Schott, Eckart

AU - Erben, Ulrike

AU - Kühl, Anja

AU - Loddenkemper, Christoph

AU - Zeitz, Martin

AU - Hamann, Alf

AU - Klugewitz, Katja

PY - 2009/12

Y1 - 2009/12

N2 - UNLABELLED: Elucidating cellular mechanisms that maintain the intrahepatic immune balance is crucial to our understanding of viral or autoimmune liver diseases and allograft acceptance. Liver sinusoidal endothelial cells (LSECs) play an important role in modifying local immune responses to tolerance in major histocompatibility complex (MHC) I-restricted models, whereas their contribution in the MHCII context is still controversial. In an MHCII chimeric mouse model that excludes MHCII-mediated antigen presentation by professional antigen-presenting cells, we demonstrated that LSECs prime CD4(+) T cells to a CD45RB(low) memory phenotype lacking marker cytokine production for effector cells that was stable in vivo following immunogenic antigen re-encounter. Although these cells, which we term T(LSEC), had the capacity to enter lymph nodes and the liver, they did not function as effector cells either in a delayed-type hypersensitivity reaction or in a hepatitis model. T(LSEC) inhibited the proliferation of naïve CD4(+) T cells in vitro although being CD25(low) and lacking expression of forkhead box protein (FoxP)3. Furthermore, these cells suppressed hepatic inflammation as monitored by alanine aminotransferase levels and cellular infiltrates in a T cell-mediated autoimmune hepatitis model in vivo.CONCLUSION: T(LSEC) first described here might belong to the expanding group of FoxP3(-) regulatory T cells. Our findings strengthen the previously discussed assumption that CD4(+) T cell priming by nonprofessional antigen-presenting cells induces anti-inflammatory rather than proinflammatory phenotypes. Because recruitment of CD4(+) T cells is increased upon hepatic inflammation, T(LSEC) might contribute to shifting antigen-dependent immune responses to tolerance toward exogenous antigens or toward endogenous self-antigens, especially under inflammatory conditions.

AB - UNLABELLED: Elucidating cellular mechanisms that maintain the intrahepatic immune balance is crucial to our understanding of viral or autoimmune liver diseases and allograft acceptance. Liver sinusoidal endothelial cells (LSECs) play an important role in modifying local immune responses to tolerance in major histocompatibility complex (MHC) I-restricted models, whereas their contribution in the MHCII context is still controversial. In an MHCII chimeric mouse model that excludes MHCII-mediated antigen presentation by professional antigen-presenting cells, we demonstrated that LSECs prime CD4(+) T cells to a CD45RB(low) memory phenotype lacking marker cytokine production for effector cells that was stable in vivo following immunogenic antigen re-encounter. Although these cells, which we term T(LSEC), had the capacity to enter lymph nodes and the liver, they did not function as effector cells either in a delayed-type hypersensitivity reaction or in a hepatitis model. T(LSEC) inhibited the proliferation of naïve CD4(+) T cells in vitro although being CD25(low) and lacking expression of forkhead box protein (FoxP)3. Furthermore, these cells suppressed hepatic inflammation as monitored by alanine aminotransferase levels and cellular infiltrates in a T cell-mediated autoimmune hepatitis model in vivo.CONCLUSION: T(LSEC) first described here might belong to the expanding group of FoxP3(-) regulatory T cells. Our findings strengthen the previously discussed assumption that CD4(+) T cell priming by nonprofessional antigen-presenting cells induces anti-inflammatory rather than proinflammatory phenotypes. Because recruitment of CD4(+) T cells is increased upon hepatic inflammation, T(LSEC) might contribute to shifting antigen-dependent immune responses to tolerance toward exogenous antigens or toward endogenous self-antigens, especially under inflammatory conditions.

KW - Animals

KW - CD4-Positive T-Lymphocytes

KW - Cell Movement

KW - Endothelial Cells

KW - Female

KW - Forkhead Transcription Factors

KW - Hepatitis, Autoimmune

KW - Interferon-gamma

KW - Interleukin-10

KW - Liver

KW - Mice

KW - Mice, Inbred C57BL

KW - T-Lymphocytes, Regulatory

U2 - 10.1002/hep.23191

DO - 10.1002/hep.23191

M3 - SCORING: Journal article

C2 - 19787806

VL - 50

SP - 1904

EP - 1913

JO - HEPATOLOGY

JF - HEPATOLOGY

SN - 0270-9139

IS - 6

ER -