Abstract
Background: The first identified susceptibility gene for Crohn’s disease, NOD2, acts as a sensor for the bacterial-wall peptidoglycan fragment muramyl dipeptide (MDP) and activates the transcription factor nuclear factor-ĸB (NF-ĸB). Upon NF-ĸB activation, intestinal macrophages (IMACs) induce expression of macrophage inflammatory protein (MIP)-3α to attract memory T lymphocytes. We therefore investigated the influence of NOD2 ligation of IMAC differentiation and functional MIP-3α induction. Methods: Human embryonal kidney HEK293 cells were transfected with NOD2 wild-type (NOD2<sup>WT</sup>) and the NOD2 SNP13 variant (NOD2<sup>L1007fsinsC</sup>) and stimulated with MDP. Recruitment of CD45R0<sup>+</sup> and Th17 cells was determined by immunohistochemistry. Results: Endogenous NOD2 stimulation was followed by a dose-dependent increase in MIP-3α secretion in MONO-MAC-6 (MM6) cells. MIP-3α mRNA was also significantly (* p < 0.05) induced in HEK293 transfected with NOD2<sup>WT</sup> via MDP ligation. In vivo cell-cell contacts between IMACs and CD45R0<sup>+</sup> memory T cells as well as recruitment of Th17 cells in patients of NOD2 variants were unchanged as compared to wild-type patients. Conclusion: Our data demonstrate a dose-dependent increase in MIP-3α secretion in the human myeloid cell line MM6 upon MDP. However, MIP-3α-driven recruitment of Th17 cells or CD45R0<sup>+</sup> memory T lymphocytes is not affected in patients carrying heterozygous NOD2 variants.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
