Leone Cathie, Le Pavec Gwenaelle, Même William, Porcheray Fabrice, Samah Boubekeur, Dormont Dominique, Gras Gabriel
Laboratoire de Neuro-Immuno-Virologie, Service de Neurovirologie UMR E-01 CEA and Université Paris-Sud XI, CRSSA, IFR13 Institut Paris Sud Cytokines, Fontenay-aux Roses, France.
Glia. 2006 Aug 15;54(3):183-92. doi: 10.1002/glia.20372.
Microglial cells are central to brain immunity and intervene in many human neurological diseases. The aim of this study was to develop a convenient cellular model for human microglial cells, suitable for HIV studies. Microglia derive from the hematogenous myelomonocytic lineage, possibly as a distinct subpopulation but in any case able to invade the CNS, proliferate, and differentiate into ameboid and then ramified microglia in the adult life. We thus attempted to derive microglia-like cells from human monocytes. When cultured with astrocyte-conditioned medium (ACM), monocytes acquired a ramified morphology, typical of microglia. They overexpressed substance P and the calcium binding protein Iba-1 and dimly expressed class II MHC, three characteristics of microglial cells. Moreover, they also expressed a potassium inward rectifier current, another microglia-specific feature. These monocyte-derived microglia-like cells (MDMi) were CD4(+)/CD14(+), evocative of an activated microglia phenotype. When treated with lipopolysaccharide (LPS), MDMi lost their overexpression of substance P, which returned to untreated monocyte-derived macrophage (MDM) level. Compared with MDM, MDMi expressed higher CD4 but lower CCR5 levels; they could be infected by HIV-1(BaL), but produced less virus progeny than MDM did. This model of human microglia may be an interesting alternative to primary microglia for large scale in vitro HIV studies and may help to better understand HIV-associated microgliosis and chronic inflammation in the brain.
小胶质细胞是脑免疫的核心，并且在许多人类神经疾病中发挥作用。本研究的目的是开发一种适用于HIV研究的便捷的人类小胶质细胞模型。小胶质细胞起源于血源性骨髓单核细胞谱系，可能作为一个独特的亚群，但无论如何都能够侵入中枢神经系统，增殖并在成年期分化为阿米巴样然后分支状的小胶质细胞。因此，我们试图从人类单核细胞中获得小胶质细胞样细胞。当与星形胶质细胞条件培养基（ACM）一起培养时，单核细胞获得了典型的小胶质细胞分支形态。它们过度表达P物质和钙结合蛋白Iba-1，并微弱表达II类MHC，这是小胶质细胞的三个特征。此外，它们还表达内向整流钾电流，这是另一个小胶质细胞特异性特征。这些单核细胞衍生的小胶质细胞样细胞（MDMi）是CD4(+)/CD14(+)，提示活化的小胶质细胞表型。当用脂多糖（LPS）处理时，MDMi失去了P物质的过度表达，其恢复到未处理的单核细胞衍生巨噬细胞（MDM）水平。与MDM相比，MDMi表达更高水平的CD4但更低水平的CCR5；它们可以被HIV-1(BaL)感染，但产生的病毒后代比MDM少。这种人类小胶质细胞模型可能是用于大规模体外HIV研究的原代小胶质细胞的一个有趣替代物，并且可能有助于更好地理解与HIV相关的小胶质细胞增生和脑中的慢性炎症。
