A Role of Nitric Oxide in the Disease Course of Experimental Retroviral Encephalopaty

在项目的第一年，我们建立了培养新生大鼠脑源性小胶质细胞的最佳条件。在小胶质细胞培养液中加入10万MW的biglican-like hematopoietic factor （BHF）后，小胶质细胞的生长速度比不加入BHF时提高了10倍。然而，在BHF培养中，逆转录病毒对小胶质细胞的感染性几乎降低。将本实验室以A8-V基因组为基础构建的携带LacZ基因组的逆转录病毒载体（见文献列表）感染培养的小胶质细胞。感染后培养的小胶质细胞几乎100%被LacZ标记。这些标记的小胶质细胞被注射到新生大鼠的大脑中。移植和标记的小胶质细胞大部分位于蛛网膜下间隙或脑血管周围间隙。接下来，将感染A8-V的小胶质细胞注射到新生大鼠大脑中。与A8-V直接感染脑相比，我们预期注射后脑内出现以海绵状变性为特征的强化病变。而受感染的小胶质细胞所引起的病变程度较轻。此外，感染的小胶质细胞植入8个月后病变消失，而直接感染A8-V的大鼠在感染8个月后出现大范围的脑海绵状变性，并在此阶段死亡。

During the first year of the project, we established the optimal condition for the culture of microglial cells derived from new-born rat brain. When the 100,000 MW biglican-like haematopoietic factor (BHF) was added to the microglial culture medium, the growth of microglia was increased by ten times of the culture without BHF. However, the infectivities of retroviruses to the microglia were almost diminished in the culture with BHF.Retroviral vector carring LacZ genom that was constructed in our laboratory based on A8-V genom (See the publication list), was infected to the cultured microglia. Nearly 100% of the cultured microglia were found to be labeled by LacZ after the infection. Those labeled microglia were injected into the new-born rat brain. Most of the transplanted and labeled microglia were found in the sub-arachnoidal space or in the perivascular space in the brain. Next, microglia infected with A8-V were injected into the new-born rat brain. We expected the enhanced lesion characterized by spongiotic degeneration in the brain after the injection compared with direct infection of the A8-V into the brain. However, the lesions induced by the infected microglia were of minimum degree. In addition, the lesions disappeared after 8 months of the implantation of the infected microglia whereas the rats that received the direct A8-V infection, exhibited wide-spread spongiotic degeneration in the brain 8 months after the infection and died at this stage.