Zhong C, Li W Z, Lü L
Department of Histology and Embryology, Shanghai Medical University 200032.
Zhonghua Yi Xue Za Zhi. 1999 Mar;79(3):174-7.
To investigate the migration and survival of B10 mouse bone marrow (BM)-derived DCs in C3H mice and if genetic modification of these DCs to overexpress TGF beta 1 may potentiate their tolerogenicity.
B10 mouse BM-derived DCs were propagated in GM-CSF and TGF beta(DC1), transduced DC1 with replication-deficient Ad vectors encoding genes for LacZ (DC2) or TGF beta 1(DC3). Cells of different groups were injected into one footpad of C3H mice. The mice were sacrificed on days 1, 2, 7, and 14, and spleens, thymuses, popliteal and mesenteric lymph nodes removed and stained with anti-IAb mAb. The incidences of B10 DC were determined by the mean number of IAb positive cells with dendriform morphology per low power field (x 100).
Transduction with Ad-LacZ or Ad-TGF beta 1 did not affect DC migration or distribution in C3H recipients, i.e. IAb+ cells were first observed under the capsule of popliteal LN (peak at d1), then migrated into the marginal T dependent area of spleens (peak at d7), and were found occasionally in the thymus. Transduction of Ad-LacZ reduced the numbers of IAb+ cells identified in both LN and spleens at all time points post injection, compared with injection of unmodified control DC, suggesting that Ad transduction itself can affect DC life span in allogeneic recipients. Overexpression of TGF beta 1 by transduction of Ad-TGF beta 1 not only fully reversed the reduction of DC numbers induced by Ad transduction, but also prolonged the life span of DC in spleen, as shown by the 2-fold increase in number of IAb+ cells in spleen at d14 compared with control DCs.
Mouse BM-derived TGF beta DCs can be transduced to express TGF beta 1 using an adenoviral vector, and exhibit the same migration characteristics as unmodified DC. The survival of TGF beta gene transduced DCs appears to be enhanced compared with unmodified or LacZ gene-transduced DCs.
研究B10小鼠骨髓来源的树突状细胞（DCs）在C3H小鼠体内的迁移和存活情况，以及对这些DCs进行基因改造使其过表达转化生长因子β1（TGFβ1）是否会增强其致耐受性。
在粒细胞-巨噬细胞集落刺激因子（GM-CSF）和TGFβ中培养B10小鼠骨髓来源的DCs（DC1），用编码LacZ基因（DC2）或TGFβ1基因（DC3）的复制缺陷型腺病毒载体转导DC1。将不同组的细胞注射到C3H小鼠的一个足垫中。在第1、2、7和14天处死小鼠，取出脾脏、胸腺、腘窝和肠系膜淋巴结，并用抗IAb单克隆抗体染色。通过每个低倍视野（×100）中具有树突状形态的IAb阳性细胞的平均数来确定B10 DC的发生率。
用腺病毒-LacZ或腺病毒-TGFβ1转导不影响DC在C3H受体中的迁移或分布，即IAb+细胞首先在腘窝淋巴结的被膜下观察到（第1天达到峰值），然后迁移到脾脏的边缘T细胞依赖区（第7天达到峰值），偶尔在胸腺中发现。与注射未修饰的对照DC相比，注射腺病毒-LacZ在注射后所有时间点都减少了在淋巴结和脾脏中鉴定出的IAb+细胞数量，这表明腺病毒转导本身会影响DC在同种异体受体中的寿命。通过腺病毒-TGFβ1转导使TGFβ1过表达不仅完全逆转了腺病毒转导诱导的DC数量减少，而且还延长了DC在脾脏中的寿命，如在第14天脾脏中IAb+细胞数量与对照DC相比增加了2倍所示。
小鼠骨髓来源的TGFβ DCs可用腺病毒载体转导以表达TGFβ1，并表现出与未修饰DC相同的迁移特性。与未修饰或LacZ基因转导的DCs相比，TGFβ基因转导的DCs的存活率似乎有所提高。
