ABSTRACT
<p><b>OBJECTIVE</b>To investigate IFN-gamma producing-cells (IFN-gamma PCs) in allogeneic mixed lymphocyte reaction (MLR) and acute graft versus host disease (aGVHD) model of mice.</p><p><b>METHODS</b>Enzyme linked immunospot assay (ELISPOT) was applied to study IFN-gamma PCs in MHC mismatched mice spleen cell MLR and aGVHD model of mice.</p><p><b>RESULT</b>IFN-gamma PCs increased significantly in MLR after allogeneic mice spleen cell stimulation. In the experimental mice aGVHD model, IFN-gamma PCs were significantly higher in the severe aGVHD group than those in the moderate aGVHD. In the moderate aGVHD group, mice with GVHD prophylaxis regimen demonstrated significantly lower level of IFN-gamma PCs, compared with those without prophylaxis. IFN-gamma PCs were significantly correlated with the GVHD clinical scores in the group with moderate aGVHD and prophylaxis regimen.</p><p><b>CONCLUSION</b>ELISPOT is a fast, sensitive and specific approach to evaluate alloresponse in allogeneic mice MLR and IFN-gamma PCs are correlated closely with the severity of aGVHD and prophylaxis regimen in the MHC-mismatched mice model.</p>
Subject(s)
Animals , Mice , Enzyme-Linked Immunosorbent Assay , Methods , Graft vs Host Disease , Allergy and Immunology , Interferon-gamma , Genetics , Mice, Inbred BALB C , Mice, Inbred C57BL , T-Lymphocytes , Allergy and Immunology , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of transforming growth factor beta1 (TGF-beta1) on dendritic cells (DC).</p><p><b>METHODS</b>Murine bone marrow cells were cultured with different cytokine combinations to develop immature DC (imDC, GM-CSF only) and TGFbeta-DC (GM-CSF + TGF-beta1), and their responses to lipopolysaccharide (LPS) stimulation were observed. The cell ultrastructure was observed by transmission electron microscopy and their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was assayed by mixed lymphocyte reaction (MLR) with BrdU incorporation. IL-12p70 protein was detected by ELISA and the expressions of Toll-like receptor 4 (TLR4) on DCs were analyzed with semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Compared to imDC, the TGFbeta-DC had no significant alterations in ultrastructure after LPS stimulation. The expressions of CD80, CD86 were lower on TGFbeta-DC than on imDC [(4.14 +/- 0.95)% vs (13.90 +/- 7.22)%; (8.60 +/- 0.75)% vs (20.63 +/- 5.03)%, P < 0.05, both]. The TGFbeta-DC kept their immature morphology after LPS stimulation, but the expressions of I-Ab and CD80 were slightly increased. After 96 h MLR, TGFbeta-DC had weaker stimulating capacity than imDC did, especially when DC/T cells ratios were 1:4 and 1:1 (P < 0.05, both). TGFbeta-DC showed impaired IL-12p70 production and down-regulation of TLR4 expression.</p><p><b>CONCLUSIONS</b>TGF-beta1 can inhibit the expression of co-stimulatory molecules on DC. The TGFbeta-DC is resistant to maturation stimulus (LPS) and might be linked with TLR4 down-regulation.</p>