A heat labile soluble factor from Bacteroides thetaiotaomicron VPI-5482 specifically increases the galactosylation pattern of HT29-MTX cells.
The aim of this work was to set up and validate an in vitro model to study a molecular response of an intestinal host cell line (HT29-MTX), to a non-pathogen microflora component. We found that Bacteroides thetaiotaomicron strain VPI-5482 had the capacity to change a specific glycosylation process in HT29-MTX cells via a mechanism that involved a soluble factor. Differentiated HT29-MTX cells were grown in the presence of 20% of spent culture supernatant from the B. thetaiotaomicron during 10 days. Glycosylation processes were followed using a large panel of lectins and analysed using confocal microscopy, western blotting and flow cytometry techniques. Our results show that a B. thetaiotaomicron soluble factor modified specifically the galactosylation pattern of HT29-MTX cells, whereas other glycosylation steps remained mainly unaffected. Further characterization of this soluble factor indicates that it is a heat labile, low molecular weight compound. Reverse transcript-PCR (RT-PCR) analysis was unable to show any significant change in mRNA expression level of the main galactosyltransferases expressed in HT29-MTX cells. By contrast, galactosyltransferase activities dramatically increased in HT29-MTX cells treated by the soluble extract of B. thetaiotaomicron, suggesting a post-translational regulation of these activities. Our in vitro model allowed us to study the cross-talk between a single bacteria and intestinal cells. The galactosylation process appears to be a target of this communication, thus uncovering a new window to study the functional consequences of co-operative symbiotic bacterial-host interactions.
Freitas
M
M
Danone VITAPOLE, 15 avenue Galilée, 92350 Le Plessis Robinson, France.
Cayuela
C
C
Antoine
J M
JM
Piller
F
F
Sapin
C
C
Trugnan
G
G
D001439:Bacteroides / Q000737:chemistry*; D001685:Biological Factors / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D015153:Blotting, Western; D002454:Cell Differentiation; D017077:Culture Media, Conditioned / Q000737:chemistry / Q000494:pharmacology; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D005434:Flow Cytometry; D005690:Galactose / Q000378:metabolism; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism; D006031:Glycosylation / Q000187:drug effects; D019073:HT29 Cells; D006358:Hot Temperature; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D037102:Lectins / Q000378:metabolism; D018613:Microscopy, Confocal; D008871:Microvilli / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D008970:Molecular Weight; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012995:Solubility; D013559:Symbiosis; D013816:Thermodynamics
D001685:Biological Factors; D017077:Culture Media, Conditioned; D037102:Lectins; D012333:RNA, Messenger; D005700:Galactosyltransferases; D018819:Dipeptidyl Peptidase 4; D005690:Galactose