[ODP-176] The microflora has an important role for the differentiation of oral immune cell
Background: The presence of microflora is inextricably linked to the host immune system. Although it has been revealed that the intestinal microflora plays an important role in the barrier function and the maturation of the immune system, the role of oral microflora in the host immune system still remains unclear. Here, we defined the role of microflora for oral immune cells.
Method: We utilized the germ-free (GF) mice and conventional (CNV) mice of 8- to12-week-old and isolated oral cells from the upper jaw that included palate and small part of gingiva from buccal side and bone marrow cells. These cells were stained with specific antibodies for analysis and analyzed by flow cytometry. MPO production was detected by ELISA. For the stimulation of oral cells, we used PMA/ionomycin and fMLP.
Results: GF mice had an increased number of neutrophils compared with CNV mice. However, oral neutrophils in GF mice included more immature populations and showed low levels of MPO releasing than CNV mice. Interestingly, CD4 T cells stimulated with PMA and ionomycin in GF mice showed weak IL-17 production compared with CNV mice. But IFN-γ production of CD4 T cells was enhanced in GF mice.
Conclusion: These results suggest that microflora might contribute not only oral but also systematic to the neutrophil functions and affect the CD4 T cell differentiation.