MICRORHEOLOGICAL STUDY ON HUMAN MONOCYTE-DERIVED DENDRITIC CELLS

Objective To Study the microrheological character and difference of different growth stages of dendritic cells(DCs),offering new technique for the DCs clinical application. Methods Peripheral blood mononuclear cells(PBMCs) were selected by the density gradient centrifugation,and the highly purified monocytes as pDCs were obtained from PBMCs by sticking wall culture and negative magnetic depletion.The pDCs were cultured in order to obtain imDCs and mDC in vitro.The characterization of pDCs,imDCs and mDCs were determined by immunochemistry,immunofluorescence,enzymology,flow cytometer etc.We measured and analyzed the electrophoretic mobility,osmotic fragility,membrane fluidity,fourier-transform infrared(FT-IR) spectrometer and viscoelastic properties of pDCs,imDCs and mDCs by microrheogical methods. Results CD14~+pDCs97% were obtained by improved isolation method.S-100 protein positive imDCs were 96.9% in total cells after cultured for 6 days with rhGM-CSF and IL-4 in vitro.And CD86~+mDCs were 87% in total cells after culture 48 hours with rhGM-CSF,IL-4 and TNF-α in vitro.The microrheological characters of pDCs and mDCs were as follows: the electrophoretic mobility of mDCs was higher than that of pDC and imDCs(P0.05);all 3 type cells have strong ability against osmotic fragility and imDCs were the strongest(the cell broken ratio is 27%);fluorescence polarization measurement indicated that the membrane fluidity of mDC was the highest and it's fluorescence polarization P value was 0.062±0.001(P0.001);the results of FT-IR spectrometer showed the changes in imDC's secondary structures of proteins.Conclusion\ The microrheological characters of DCs are notably changed depend on their different developing stages.