Enhanced CD4+ T Cell Proliferation and Th2 Cytokine Production in DR6-Deficient Mice

<p>CTLA-4 is the major nefative regulator of T cell response. We have analyzed the expression of CTLA-4 in human monocytes and monocyte-derived DCs and the effects of its engagement on cytokine production and T cell stimulatory activity by mature DCs (mDCs). We found the CTLA-4 was highly expressed on freshly isolated monocytes, then down-modulated on the immature DCs (iDCs) and upregulated on mDCs. Treatment of mDCS with an agonistic anti-CTLA-4 m Ab enhanced secretion of IL-10 but reduced secretion of IL-8 and IL-12, as well as autologous CD4* T-cell proliferation in response to simulation with PPD recall antigenloaded-DCs. Neutralization of IL-10 with an anti-IL-10 antibody partially restored the ability of anti-CTLA-4-treated mDCs to stimulate T cell proliferation in response to PPD. Our data provide the first evidence that CTLA-4 receptor is expressed by human mDCs and exerts immune modulatory effects in these cells.</p>

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Regulatory T Cells Accumulate in the Lung Allergic Inflammation and Efficiently Suppress T-Cell Proliferation but Not Th2 Cytokine Production

Clinical and Developmental Immunology ◽

10.1155/2012/721817 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13 ◽

Cited By ~ 22

Author(s):

Lucas Faustino ◽

Daniel Mucida ◽

Alexandre Castro Keller ◽

Jocelyne Demengeot ◽

Karina Bortoluci ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

Regulatory T Cells ◽

Cytokine Production ◽

Allergic Inflammation ◽

Peripheral Tolerance ◽

Effector Memory ◽

T Cell Proliferation ◽

Th2 Cytokine

Foxp3+CD25+CD4+regulatory T cells are vital for peripheral tolerance and control of tissue inflammation. In this study, we characterized the phenotype and monitored the migration and activity of regulatory T cells present in the airways of allergic or tolerant mice after allergen challenge. To induce lung allergic inflammation, mice were sensitized twice with ovalbumin/aluminum hydroxide gel and challenged twice with intranasal ovalbumin. Tolerance was induced by oral administration of ovalbumin for 5 consecutive days prior to OVA sensitization and challenge. We detected regulatory T cells (Foxp3+CD25+CD4+T cells) in the airways of allergic and tolerant mice; however, the number of regulatory T cells was more than 40-fold higher in allergic mice than in tolerant mice. Lung regulatory T cells expressed an effector/memory phenotype (CCR4highCD62LlowCD44highCD54highCD69+) that distinguished them from naive regulatory T cells (CCR4intCD62LhighCD44intCD54intCD69−). These regulatory T cells efficiently suppressed pulmonary T-cell proliferation but not Th2 cytokine production.

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Triterpene Acids from Rose Hip Powder Inhibit Self-antigen- and LPS-induced Cytokine Production and CD4+ T-cell Proliferation in Human Mononuclear Cell Cultures

Phytotherapy Research ◽

10.1002/ptr.3713 ◽

2011 ◽

Vol 26 (8) ◽

pp. 1142-1147 ◽

Cited By ~ 7

Author(s):

Lasse Saaby ◽

Claus Henrik Nielsen

Keyword(s):

Cell Proliferation ◽

T Cell ◽

Mononuclear Cell ◽

Cell Cultures ◽

Cytokine Production ◽

Cd4 T Cell ◽

T Cell Proliferation ◽

Human Mononuclear Cell ◽

Rose Hip ◽

Self Antigen

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Faculty Opinions recommendation of Epidermal and dermal dendritic cells display differential activation and migratory behavior while sharing the ability to stimulate CD4+ T cell proliferation in vivo.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1121863.578941 ◽

2008 ◽

Author(s):

James Campbell

Keyword(s):

Cell Proliferation ◽

Dendritic Cells ◽

T Cell ◽

Cd4 T Cell ◽

T Cell Proliferation ◽

Migratory Behavior ◽

Differential Activation

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Keratinocytes Regulate the Threshold of Inflammation by Inhibiting T Cell Effector Functions

Cells ◽

10.3390/cells10071606 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1606

Author(s):

Peter Seiringer ◽

Stefanie Eyerich ◽

Kilian Eyerich ◽

Daniela Dittlein ◽

Anna Caroline Pilz ◽

...

Keyword(s):

Cell Proliferation ◽

T Cell ◽

Cytokine Production ◽

Nickel Sulfate ◽

Human Keratinocytes ◽

T Cell Proliferation ◽

Effector Functions ◽

The Impact ◽

Cell Effector

Whilst the importance of keratinocytes as a first-line defense has been widely investigated, little is known about their interactions with non-resident immune cells. In this study, the impact of human keratinocytes on T cell effector functions was analyzed in an antigen-specific in vitro model of allergic contact dermatitis (ACD) to nickel sulfate. Keratinocytes partially inhibited T cell proliferation and cytokine production. This effect was dependent on the keratinocyte/T cell ratio and was partially reversible by increasing the number of autologous dendritic cells. The inhibition of T cell proliferation by keratinocytes was independent of the T cell subtype and antigen presentation by different professional antigen-presenting cells. Autologous and heterologous keratinocytes showed comparable effects, while the fixation of keratinocytes with paraformaldehyde abrogated the immunosuppressive effect. The separation of keratinocytes and T cells by a transwell chamber, as well as a cell-free keratinocyte supernatant, inhibited T cell effector functions to the same amount as directly co-cultured keratinocytes, thus proving that soluble factor/s account for the observed suppressive effects. In conclusion, keratinocytes critically control the threshold of inflammatory processes in the skin by inhibiting T cell proliferation and cytokine production.

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