Regulation of 25-hydroxyvitamin D3-1α-hydroxylase and production of 1α,25-dihydroxyvitamin D3 by human dendritic cells

Abstract25-Hydroxyvitamin D3-1α-hydroxylase (25(OH)D3-1α-hydroxylase), the key enzyme of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) production, is expressed in monocyte-derived macrophages (MACs). Here we show for the first time constitutive expression of 25(OH)D3-1α-hydroxylase in monocyte-derived dendritic cells (DCs), which was increased after stimulation with lipopolysaccharide (LPS). Accordingly, DCs showed low constitutive production of 1,25(OH)2D3, but activation by LPS increased 1,25(OH)2D3 synthesis. In addition, 25(OH)D3-1α-hydroxylase expression was found in blood DCs but not in CD34+-derived DCs. Next we analyzed the functional consequences of these results. Addition of 1,25(OH)2D3 at concentrations comparable with those produced by DCs inhibited the allostimulatory potential of DCs during the early phase of DC differentiation. However, terminal differentiation decreased the responsiveness of DCs to 1,25(OH)2D3. In conclusion, DCs are able to produce 1,25(OH)2D3 especially following stimulation with LPS. Terminal maturation renders DCs unresponsive to the effects of 1,25(OH)2D3, but those cells are able to suppress the differentiation of their own precursor cells in a paracrine way through the production of 1,25(OH)2D3.

Download Full-text

Development of an IP-Free Biotechnology Platform for Constitutive Production of HPV16 L1 Capsid Protein Using thePichia pastoris PGK1Promoter

BioMed Research International ◽

10.1155/2015/594120 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

F. C. Mariz ◽

E. C. Coimbra ◽

A. L. S. Jesus ◽

L. M. Nascimento ◽

F. A. G. Torres ◽

...

Keyword(s):

Capsid Protein ◽

Signal Sequence ◽

Constitutive Expression ◽

Methylotrophic Yeast ◽

Yeast Cells ◽

Dot Blot ◽

Intracellular Expression ◽

Constitutive Production ◽

L1 Protein ◽

First Time

The human papillomavirus (HPV) L1 major capsid protein, which forms the basis of the currently available vaccines against cervical cancer, self-assembles into virus-like particles (VLPs) when expressed heterologously. We report the development of a biotechnology platform for HPV16 L1 protein expression based on the constitutivePGK1promoter (PPGK1) from the methylotrophic yeastPichia pastoris. The L1 gene was cloned under regulation ofPPGK1into pPGKΔ3 expression vector to achieve intracellular expression. In parallel, secretion of the L1 protein was obtained through the use of an alternative vector called pPGKΔ3α, in which a codon optimizedα-factor signal sequence was inserted. We devised a work-flow based on the detection of the L1 protein by dot blot, colony blot, and western blot to classify the positive clones. Finally, intracellular HPV VLPs assembly was demonstrated for the first time in yeast cells. This study opens up perspectives for the establishment of an innovative platform for the production of HPV VLPs or other viral antigens for vaccination purposes, based on constitutive expression inP. pastoris.

Download Full-text

DC-SIGN signalling induced by Trichinella spiralis products contributes to the tolerogenic signatures of human dendritic cells

Scientific Reports ◽

10.1038/s41598-020-77497-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jelena Cvetkovic ◽

Nataša Ilic ◽

Alisa Gruden-Movsesijan ◽

Sergej Tomic ◽

Ninoslav Mitic ◽

...

Keyword(s):

Dendritic Cells ◽

Trichinella Spiralis ◽

T Cell Response ◽

Toll Like Receptor ◽

Tolerogenic Dendritic Cells ◽

Toll Like Receptor 2 ◽

Secretory Products ◽

Human Dendritic Cells ◽

First Time

AbstractTolerogenic dendritic cells (tolDCs) are central players in the maintenance of immune tolerance and thereby have been identified as the most favourable candidates for cell therapy of autoimmune diseases. We have recently shown that excretory-secretory products (ES L1) released by Trichinella spiralis larvae induce stable human tolDCs in vitro via Toll-like receptor 2 (TLR2) and TLR4. However, engagement of these receptors did not fully explain the tolerogenic profile of DCs. Here, we observed for the first time that dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) interacts with highly glycosylated ES L1 and contributes to the generation of ES L1-induced tolDCs. Blocking DC-SIGN interfered with the ES L1-induced higher expression of CD40 and CCR7 and the production of IL-10 and TGF-β by DCs. The cooperation of TLR2, TLR4 and DC-SIGN receptors is of importance for the capacity of DCs to prime T cell response toward Th2 and to induce expansion of CD4+CD25+Foxp3+ T cells, as well as for the production of IL-10 and TGF-β by these cells. Overall, these results indicate that induction of tolDCs by ES L1 involves engagement of multiple pattern recognition receptors namely, TLR2, TLR4 and DC-SIGN.

Download Full-text

Mesoporous Silicon Microparticles Enhance MHC Class I Cross-Antigen Presentation by Human Dendritic Cells

Clinical and Developmental Immunology ◽

10.1155/2013/362163 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 19

Author(s):

A. Jiménez-Periáñez ◽

B. Abos Gracia ◽

J. López Relaño ◽

C. M. Diez-Rivero ◽

P. A. Reche ◽

...

Keyword(s):

Dendritic Cells ◽

T Lymphocytes ◽

Mhc Class I ◽

Cytotoxic T Lymphocytes ◽

Class I ◽

Antigenic Peptides ◽

Mesoporous Silicon ◽

Human Dendritic Cells ◽

Antigen Presenting ◽

First Time

The mesoporous silicon microparticles (MSMPs) are excellent vehicles for releasing molecules inside the cell. The aim of this work was to use MSMPs to deliver viral specific MHC class I restricted epitopes into human antigen presenting cells (monocyte derived dendritic cells, MDDCs) to facilitate their capture, processing, and presentation to CD8+ (cytotoxic) T lymphocytes. We show for the first time that MSMPs vehiculation of antigenic peptides enhances their MHC class I presentation by human MDDCs to CD8 T lymphocytes.

Download Full-text