Inhibition of the differentiation of monocyte-derived dendritic cells by human gingival fibroblasts.
We investigated whether gingival fibroblasts (GFs) can modulate the differentiation and/or maturation of monocyte-derived dendritic cells (DCs) and analyzed soluble factors that may be involved in this immune modulation. Experiments were performed using human monocytes in co-culture with human GFs in Transwell® chambers or using monocyte cultures treated with conditioned media (CM) from GFs of four donors. The four CM and supernatants from cell culture were assayed by ELISA for cytokines involved in the differentiation of dendritic cells, such as IL-6, VEGF, TGFβ1, IL-13 and IL-10. The maturation of monocyte-derived DCs induced by LPS in presence of CM was also studied. Cell surface phenotype markers were analyzed by flow cytometry. In co-cultures, GFs inhibited the differentiation of monocyte-derived DCs and the strength of this blockade correlated with the GF/monocyte ratio. Conditioned media from GFs showed similar effects, suggesting the involvement of soluble factors produced by GFs. This inhibition was associated with a lower stimulatory activity in MLR of DCs generated with GFs or its CM. Neutralizing antibodies against IL-6 and VEGF significantly (P<0.05) inhibited the inhibitory effect of CM on the differentiation of monocytes-derived DCs and in a dose dependent manner. Our data suggest that IL-6 is the main factor responsible for the inhibition of DCs differentiation mediated by GFs but that VEGF is also involved and constitutes an additional mechanism.
Inserm U970 Team Laboratory of Arterial Repair, Université Paris Descartes, Sorbonne Paris Cité, PARCC/Hopital Européen Georges Pompidou, Paris, France. sylvie.seguier@parisdescartes.fr
Sylvie
S
Séguier
Eric
E
Tartour
Coralie
C
Guérin
Ludovic
L
Couty
Mathilde
M
Lemitre
Laetitia
L
Lallement
Marysette
M
Folliguet
Samah
S
El Naderi
Magali
M
Terme
Cécile
C
Badoual
Antoine
A
Lafont
Bernard
B
Coulomb
D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D018920:Coculture Techniques; D017077:Culture Media, Conditioned / Q000494:pharmacology; D016207:Cytokines / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D005434:Flow Cytometry; D005881:Gingiva / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017077:Culture Media, Conditioned; D016207:Cytokines; D008070:Lipopolysaccharides; D012333:RNA, Messenger