OBJECTIVETo investigate the regulation of adipose-derived mesenchymal stem cells (ADSC) on helper T cells and regulatory T cells in allergic rhinitis(AR) mouse model and the underlying mechanisms.

METHODSUsing random number table, 60 Balb/c mice were divided into 6 groups (represented by: sensitized/challenged/treated ), they were the experimental group 1(OVA/OVA/high dose ADSC), the experimental group 2(OVA/OVA/low dose ADSC), the experimental group 3(OVA/OVA/PBS), the experimental group 4(OVA/OVA/0), the control group 1(PBS/PBS/0) and the control group 2(0/0/0). The mouse ADSC were isolated and cultured through conventional method, and AR mouse model was built with OVA and aluminum. The mice were injected with high (3×10(6)), low (1×10(6)) ADSC respectively labeled by CM-Dil for 3 consecutive days via tail-vein injection and sacrificed 48 hours later. Finally, levels of IL-4, IL-6, IL-10 and IFN -γ in serum were examined by ELISA; expressions of the four cytokines in spleen were examined by q RT-PCR; migration of ADSC to mouse model nasal mucosa were observed through fluorescence microscope; eosinophil infiltration were observed by the nasal HE staining.

RESULTSMouse ADSC was isolated, cultured and identified successfully. There was significant difference in symptom scores of AR models (compared with 0/0/0 group, P<0.01). The IL-4 and IL-6 levels of OVA/OVA/high ADSC group were significantly lower than OVA/OVA/0 group (group 1: (17.95±7.78), (27.51±5.93) pg/ml; group 4: (56.82±9.12), (70.03±7.22) pg/ml), the IFN-γ and IL-10 levels increased significantly (group 1: (367.74±13.79), (417.10±72.40) pg/ml; group 4: (199.46±11.25), (122.50±15.57) pg/ml) in serum. These differences were statistically significant(P<0.01). Compared with OVA/OVA/low ADSC group, the IL-4 and IL-6 levels decreased significantly (group 1: (17.95±7.78), (27.51±5.93) pg/ml; group 2: (41.57±12.27), (56.21±9.23)pg/ml) of OVA / OVA / high ADSC group, and the IFN-γ and IL-10 increased significantly (group 1: (367.74±13.79), (417.10±72.40)pg/ml; group 2: (281.77±30.41), (203.45±87.10) pg/ml). These differences were statistically significant(P<0.01). At the same time, the corresponding changes observed at the levels of the cytokines' mRNA. ADSC labeled by CM-Dil could migrate to the mouse nasal mucosa. OVA/OVA/high ADSC group showed the more red fluorescence than the OVA/OVA/low ADSC group. The eosinophils in nasal mucosa of the two groups reduced compared with the normal control.

CONCLUSIONADSC injected via tail-vein can migrate to nasal mucosa and play non-specific immune effects, that may to effect the releases of some cytokines then to regulate the Th1/Th2 imbalance and the function of Treg cell, finally that be dose-related in a certain extent.