Myeloid dendritic cells isolated from tissues of SIV-infected Rhesus macaques promote the induction of regulatory T cells

Abstract Rhesus (Macaca mulatta) and cynomolgus (Macaca fasicularis) macaques of distinct genetic origin are understood to vary in susceptibility to Mycobacterium tuberculosis, and therefore differences in their immune systems may account for the differences in disease control. Monocyte:lymphocyte (M:L) ratio has been identified as a risk factor for M. tuberculosis infection and is known to vary between macaque species. We aimed to characterise the constituent monocyte and lymphocyte populations between macaque species, and profile other major immune cell subsets including: CD4+ and CD8+ T-cells, NK-cells, B-cells, monocyte subsets and myeloid dendritic cells. We found immune cell subsets to vary significantly between macaque species. Frequencies of CD4+ and CD8+ T-cells and the CD4:CD8 ratio showed significant separation between species, while myeloid dendritic cells best associated macaque populations by M. tuberculosis susceptibility. A more comprehensive understanding of the immune parameters between macaque species may contribute to the identification of new biomarkers and correlates of protection.

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Tumor cells convert immature myeloid dendritic cells into TGF-β–secreting cells inducing CD4+CD25+ regulatory T cell proliferation

Journal of Experimental Medicine ◽

10.1084/jem.20050463 ◽

2005 ◽

Vol 202 (7) ◽

pp. 919-929 ◽

Cited By ~ 487

Author(s):

François Ghiringhelli ◽

Pierre E. Puig ◽

Stephan Roux ◽

Arnaud Parcellier ◽

Elise Schmitt ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

Dendritic Cells ◽

Regulatory T Cells ◽

Tumor Cells ◽

Transforming Growth Factor ◽

Dependent Manner ◽

Myeloid Dendritic Cells ◽

Β Receptor ◽

Necessary And Sufficient

The mechanisms through which regulatory T cells accumulate in lymphoid organs of tumor-bearing hosts remain elusive. Our experiments indicate that the accumulation of CD4+CD25+ regulatory T cells (T reg cells) expressing FoxP3 and exhibiting immunosuppressive function originates from the proliferation of naturally occurring CD25+ T cells and requires signaling through transforming growth factor (TGF)–β receptor II. During tumor progression, a subset of dendritic cells (DCs) exhibiting a myeloid immature phenotype is recruited to draining lymph nodes. This DC subset selectively promotes the proliferation of T reg cells in a TGF-β–dependent manner in mice and rats. Tumor cells are necessary and sufficient to convert DCs into regulatory cells that secrete bioactive TGF-β and stimulate T reg cell proliferation. In conclusion, tumor expansion can stimulate T reg cells via a specific DC subset.

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Recent Advances in Psoriasis Research; the Clue to Mysterious Relation to Gut Microbiome

International Journal of Molecular Sciences ◽

10.3390/ijms21072582 ◽

2020 ◽

Vol 21 (7) ◽

pp. 2582 ◽

Cited By ~ 3

Author(s):

Mayumi Komine

Keyword(s):

Diabetes Mellitus ◽

T Cells ◽

Dendritic Cells ◽

Cardiovascular Diseases ◽

Regulatory T Cells ◽

Gut Microbiota ◽

Psoriatic Skin ◽

Myeloid Dendritic Cells ◽

Inflammatory Status ◽

Recent Advances

Psoriasis is a chronic inflammatory cutaneous disease, characterized by activated plasmacytoid dendritic cells, myeloid dendritic cells, Th17 cells, and hyperproliferating keratinocytes. Recent studies revealed skin-resident cells have pivotal roles in developing psoriatic skin lesions. The balance in effector T cells and regulatory T cells is disturbed, leading Foxp3-positive regulatory T cells to produce proinflammatory IL-17. Not only acquired but also innate immunity is important in psoriasis pathogenesis, especially in triggering the disease. Group 3 innate lymphoid cell are considered one of IL-17-producing cells in psoriasis. Short chain fatty acids produced by gut microbiota stabilize expression of Foxp3 in regulatory T cells, thereby stabilizing their function. The composition of gut microbiota influences the systemic inflammatory status, and associations been shown with diabetes mellitus, cardiovascular diseases, psychomotor diseases, and other systemic inflammatory disorders. Psoriasis has been shown to frequently comorbid with diabetes mellitus, cardiovascular diseases, psychomotor disease and obesity, and recent report suggested the similar abnormality in gut microbiota as the above comorbid diseases. However, the precise mechanism and relation between psoriasis pathogenesis and gut microbiota needs further investigation. This review introduces the recent advances in psoriasis research and tries to provide clues to solve the mysterious relation of psoriasis and gut microbiota.

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Expansion of FOXP3high regulatory T cells by human dendritic cells (DCs) in vitro and after injection of cytokine-matured DCs in myeloma patients

Blood ◽

10.1182/blood-2006-03-011353 ◽

2006 ◽

Vol 108 (8) ◽

pp. 2655-2661 ◽

Cited By ~ 221

Author(s):

Devi K. Banerjee ◽

Madhav V. Dhodapkar ◽

Elyana Matayeva ◽

Ralph M. Steinman ◽

Kavita M. Dhodapkar

Keyword(s):

T Cells ◽

Dendritic Cells ◽

T Cell ◽

Regulatory T Cells ◽

Interleukin 2 ◽

Cell Contact ◽

Myeloid Dendritic Cells ◽

Healthy Donors

AbstractCD4+CD25+FOXP3+ regulatory T cells (Treg's) play an important role in the maintenance of immune tolerance. The mechanisms controlling the induction and maintenance of Treg's in humans need to be defined. We find that human myeloid dendritic cells (DCs) are superior to other antigen presenting cells for the maintenance of FOXP3+ Treg's in culture. Coculture of DCs with autologous T cells leads to an increase in both the number of Treg's, as well as the expression of FOXP3 protein per cell both in healthy donors and myeloma patients. DC-mediated expansion of FOXP3high Treg's is enhanced by endogenous but not exogenous interleukin-2 (IL-2), and DC-T-cell contact, including the CD80/CD86 membrane costimulatory molecules. DCs also stimulate the formation of Treg's from CD25- T cells. The efficacy of induction of Treg's by DCs depends on the nature of the DC maturation stimulus, with inflammatory cytokine-treated DCs (Cyt-DCs) being the most effective Treg inducers. DC-induced Treg's from both healthy donors and patients with myeloma are functional and effectively suppress T-cell responses. A single injection of cytokine-matured DCs led to rapid enhancement of FOXP3+ Treg's in vivo in 3 of 3 myeloma patients. These data reveal a role for DCs in increasing the number of functional FOXP3high Treg's in humans.

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