Research On The Differentiation Of Dendritic Cells Of Systemic Lupus Erythematosus

To study the function of the dendritic cells (DC) in the systemic lupus erythematosus (SLE), we induced the monocytes in the different culture systems. First, normal monocytes were seeded in the SLE serum, GM-CSF/IL-4 system or in the normal serum. We investigate the expression of the HLA-DR and CD80 during the culture time by flow cytomitry. Stimulatory effect was assessed by the 3H incorporation test. We found cells indeed differentiated into DC in SLE serum but not in normal serum. Yet, even in the termination of the culture time, DC in the SLE serum expressed HLA-DR and CD80 much lower than what happened in the GM-CSF/IL-4 system. 3H incorporation test also suggested the cells in the SLE serum were on the immature stage. Second, we constructed a model mimicking the environment of DC differentiation based on the reverse-traffic through the endothelial layer. In this model, we found SLE monocyte, which had been proved to secret much higher TNF-alpha, differentiated into cells with striking higher expression of CD80 and CD86. However, the cells still lacked the overwhelming stimulatory effect compared with the DC (express low CD80/CD86) derived from normal monocyte. The SLE monocyte-derived DC (SMDC), compared with the normal monocyte-derived DC (NMDC), secreted much lower IFN-gama. SMDC or NMDC could not induce the apoptosis of T cells. And in the autologous proliferation test, the apoptotic cells induced in the serum-deprived culture could not trigger the propagation of lymphocytes stimulated by the autologous SMDC or NMDC. The research implied the dysfunction of dendritic cells of systemic lupus erythematosus.