申请者已从人树突状细胞cDNA文库中经随机测序克隆到一个与TNF-a同源的TNF家族新分子（暂命为DTL）并表达纯化出其重组蛋白，拟在此基础上进一步探讨其对不同来源的树突状细疤宸只⒂挠跋旌推渥饔霉痰男藕糯加牖虻骺鼗疲用孀罱飧眯路肿拥拿庖哐Чδ芗捌渥饔没恚⒍允魍蛔聪赴姆只⒂懈钊氲娜鲜丁

A new cytokine cDNA was isolated from human dendritic cell and it was termed DTL (DC Derived TNF-a Like Cytokine). It's GeneBank number is AF134715. For the prokayotic expression, recombinant expression vector with oriental insertion of DTL cDNA, pBV-DTL, was constructed using pBV220 expression vector. The recombinant protein was obtained after heat-induction, whose purificity reached over 95% after purification. Animals were immunized and the antiserum with a titre of 1:5000 was generated. DTL polyclonal Ag was purified by saturated (NH4)2SO4 precipitation and affinity chromatography. The Effects of DTL on the development and differentiation of DC derived from monocytes were observed. The results showed that DTL could promote the differentiation of monocytes to DC in combination with IL-4. But no syngernic effects were observed between DTL and GM-CSF. DTL could induce maturation of inmature DC, but the maturation effect was less potent than TNF-a, which is a known mediator of DC function. The results also revealed that the viability of CD34+ cells cultured with DTL was augmented and typical phenotypes of monocytes were shown after cultured with 100 ng/ml DTL for 14 days. It was suggested that the effect of DTL itself was similar to GM-CSF as it could induce CD34+ cells to differentiate to monocytes; but this activity was weaker than that of GM-CSF, and DTL itself couldn't promote CD34+ cells to proliferate markedly as GM-CSF. When combined with TNF-a, DTL could induce CD34+ cells to differentiate to DC, but could not promote them to proliferate. When CD34+cells were cultured with DTL combined with GM-CSF and TNF-a, the cells not only differentiated to typical DC but also proliferated markablely. In addition, we also found that the psoriatic lesional keratinocytes could augment the maturation of human monocytes-derived langerhans cells found that TRAIL was involvedinto the cytotoxicity of lipopolysaccharide-stimulated dendritic cells to activated T cells. We publicated 16 papers