Limits...
Microbiota/host crosstalk biomarkers: regulatory response of human intestinal dendritic cells exposed to Lactobacillus extracellular encrypted peptide.

Bernardo D, Sánchez B, Al-Hassi HO, Mann ER, Urdaci MC, Knight SC, Margolles A - PLoS ONE (2012)

Bottom Line: Our data suggest that some of the molecular dialogue between intestinal bacteria and DCs may be mediated by immunomodulatory peptides, encoded in larger extracellular proteins, secreted by commensal bacteria.These peptides may be used for the development of nutraceutical products for patients with IBD.In addition, this kind of peptides seem to be absent in the gut of inflammatory bowel disease patients, suggesting a potential role as biomarker of gut homeostasis.

View Article: PubMed Central - PubMed

Affiliation: Antigen Presentation Research Group, Imperial College London, Harrow, United Kingdom.

ABSTRACT
The human gastrointestinal tract is exposed to a huge variety of microorganisms, either commensal or pathogenic; at this site, a balance between immunity and immune tolerance is required. Intestinal dendritic cells (DCs) control the mechanisms of immune response/tolerance in the gut. In this paper we have identified a peptide (STp) secreted by Lactobacillus plantarum, characterized by the abundance of serine and threonine residues within its sequence. STp is encoded in one of the main extracellular proteins produced by such species, which includes some probiotic strains, and lacks cleavage sites for the major intestinal proteases. When studied in vitro, STp expanded the ongoing production of regulatory IL-10 in human intestinal DCs from healthy controls. STp-primed DC induced an immunoregulatory cytokine profile and skin-homing profile on stimulated T-cells. Our data suggest that some of the molecular dialogue between intestinal bacteria and DCs may be mediated by immunomodulatory peptides, encoded in larger extracellular proteins, secreted by commensal bacteria. These peptides may be used for the development of nutraceutical products for patients with IBD. In addition, this kind of peptides seem to be absent in the gut of inflammatory bowel disease patients, suggesting a potential role as biomarker of gut homeostasis.

Show MeSH

Related in: MedlinePlus

Structure, purification and location of the ST peptide.a) Domain structure of the protein D1, where the ST peptide is encoded (S/T domain); b) Western blot performed with a specific horseradish peroxidase-conjugated anti His5 antibody, showing the anomalous migration of the purified His-tagged ST peptide (marked with an arrow); c) Western blot using the polyclonal anti-STp serum as primary antibody; specific immunoreactive bands are labelled with arrows; -: complete medium (negative control), HC#: protein extracts obtained from culture supernatants of healthy colonic biopsies, F#: Some culture supernatants were 0.2 µm filtered prior to protein extraction, D# and E#: protein extracts from culture supernatants of human epidermal and dermal layer cultures respectively.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3351486&req=5

pone-0036262-g001: Structure, purification and location of the ST peptide.a) Domain structure of the protein D1, where the ST peptide is encoded (S/T domain); b) Western blot performed with a specific horseradish peroxidase-conjugated anti His5 antibody, showing the anomalous migration of the purified His-tagged ST peptide (marked with an arrow); c) Western blot using the polyclonal anti-STp serum as primary antibody; specific immunoreactive bands are labelled with arrows; -: complete medium (negative control), HC#: protein extracts obtained from culture supernatants of healthy colonic biopsies, F#: Some culture supernatants were 0.2 µm filtered prior to protein extraction, D# and E#: protein extracts from culture supernatants of human epidermal and dermal layer cultures respectively.

Mentions: In the present work, we have characterized the interaction of a single peptide, encoded in the amino acid sequence of protein D1 (homologous to gi/28270057 from L. plantarum WCFS1) [25], with human DCs. The bioinformatic analysis of the D1 amino acid sequence revealed an internal region with a relatively high abundance of uncharged polar amino acids. This region had a predicted molecular mass of 6.8 kDa, and contained 22.7% of serine and 31.8% of threonine. Polar uncharged amino acids represented around 83% of the total amino acids (Figure 1a). Given the particular patterns of repeated serines and threonines, and its high content in these amino acids, we have denominated such region as STp and we produced and purified it using a recombinant Lactococcus lactis strain.


Microbiota/host crosstalk biomarkers: regulatory response of human intestinal dendritic cells exposed to Lactobacillus extracellular encrypted peptide.

Bernardo D, Sánchez B, Al-Hassi HO, Mann ER, Urdaci MC, Knight SC, Margolles A - PLoS ONE (2012)

Structure, purification and location of the ST peptide.a) Domain structure of the protein D1, where the ST peptide is encoded (S/T domain); b) Western blot performed with a specific horseradish peroxidase-conjugated anti His5 antibody, showing the anomalous migration of the purified His-tagged ST peptide (marked with an arrow); c) Western blot using the polyclonal anti-STp serum as primary antibody; specific immunoreactive bands are labelled with arrows; -: complete medium (negative control), HC#: protein extracts obtained from culture supernatants of healthy colonic biopsies, F#: Some culture supernatants were 0.2 µm filtered prior to protein extraction, D# and E#: protein extracts from culture supernatants of human epidermal and dermal layer cultures respectively.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3351486&req=5

pone-0036262-g001: Structure, purification and location of the ST peptide.a) Domain structure of the protein D1, where the ST peptide is encoded (S/T domain); b) Western blot performed with a specific horseradish peroxidase-conjugated anti His5 antibody, showing the anomalous migration of the purified His-tagged ST peptide (marked with an arrow); c) Western blot using the polyclonal anti-STp serum as primary antibody; specific immunoreactive bands are labelled with arrows; -: complete medium (negative control), HC#: protein extracts obtained from culture supernatants of healthy colonic biopsies, F#: Some culture supernatants were 0.2 µm filtered prior to protein extraction, D# and E#: protein extracts from culture supernatants of human epidermal and dermal layer cultures respectively.
Mentions: In the present work, we have characterized the interaction of a single peptide, encoded in the amino acid sequence of protein D1 (homologous to gi/28270057 from L. plantarum WCFS1) [25], with human DCs. The bioinformatic analysis of the D1 amino acid sequence revealed an internal region with a relatively high abundance of uncharged polar amino acids. This region had a predicted molecular mass of 6.8 kDa, and contained 22.7% of serine and 31.8% of threonine. Polar uncharged amino acids represented around 83% of the total amino acids (Figure 1a). Given the particular patterns of repeated serines and threonines, and its high content in these amino acids, we have denominated such region as STp and we produced and purified it using a recombinant Lactococcus lactis strain.

Bottom Line: Our data suggest that some of the molecular dialogue between intestinal bacteria and DCs may be mediated by immunomodulatory peptides, encoded in larger extracellular proteins, secreted by commensal bacteria.These peptides may be used for the development of nutraceutical products for patients with IBD.In addition, this kind of peptides seem to be absent in the gut of inflammatory bowel disease patients, suggesting a potential role as biomarker of gut homeostasis.

View Article: PubMed Central - PubMed

Affiliation: Antigen Presentation Research Group, Imperial College London, Harrow, United Kingdom.

ABSTRACT
The human gastrointestinal tract is exposed to a huge variety of microorganisms, either commensal or pathogenic; at this site, a balance between immunity and immune tolerance is required. Intestinal dendritic cells (DCs) control the mechanisms of immune response/tolerance in the gut. In this paper we have identified a peptide (STp) secreted by Lactobacillus plantarum, characterized by the abundance of serine and threonine residues within its sequence. STp is encoded in one of the main extracellular proteins produced by such species, which includes some probiotic strains, and lacks cleavage sites for the major intestinal proteases. When studied in vitro, STp expanded the ongoing production of regulatory IL-10 in human intestinal DCs from healthy controls. STp-primed DC induced an immunoregulatory cytokine profile and skin-homing profile on stimulated T-cells. Our data suggest that some of the molecular dialogue between intestinal bacteria and DCs may be mediated by immunomodulatory peptides, encoded in larger extracellular proteins, secreted by commensal bacteria. These peptides may be used for the development of nutraceutical products for patients with IBD. In addition, this kind of peptides seem to be absent in the gut of inflammatory bowel disease patients, suggesting a potential role as biomarker of gut homeostasis.

Show MeSH
Related in: MedlinePlus