Le Jan Christian, Bellaton Claire, Greenland Timothy, Mornex Jean-François
UMR 754, Rétrovirus et Pathologie Comparée, INRA/ENVL/UCBL/EPHE, Université Claude Bernard Lyon 1, IFR 128 Biosciences Lyon Gerland, France.
Reprod Nutr Dev. 2005 Jul-Aug;45(4):513-23. doi: 10.1051/rnd:2005035.
Transmission of Caprine Arthritis Encephalitis virus (CAEV) from the mother to offspring is principally mediated by infected cells from colostrum and milk. The infection of the dam is often sub-clinical, and results in increased cellularity of milk, sometimes exacerbated by bacterial co-infections. Although monocytes are the major viral host cells, several other cell types, including epithelial mammary cells, fibroblasts and endothelial cells show low levels of in vivo infection. In vitro, however, all phenotypes of mammary gland cells are individually highly sensitive to CAEV infection. This suggests that local mechanisms act to control viral expression. Our goal is to analyse the mechanisms regulating local virus infection, including the physiological status of the mammary gland and bacterial co-infections. In this work, we present the development of a model for the in vitro reconstitution of mammary gland tissue using 3D cultures in Matrigel. Mononuclear cells from the blood are added to the 3D cultures in vitro. In these experimental conditions, the mammary cells spontaneously organize into mammospheres. Blood leucocytes migrate into the culture gel, and localize particularly at the periphery of the mammospheres. Mammospheres were susceptible to infection in vitro by CAEV, as shown by a cytopathic effect and expression of late CAEV antigen p30. This model will allow the in vitro study of virus expression, transfer of infection to mammary gland cells and interactions between the mammary gland cells, infected monocytes and immunocompetent cells. It will allow the study of mechanisms participating in the control of passage of pathogens into milk, according to the physiological and CAEV-infection status of the animal, microenvironment and the presence of bacterial co-infections.
山羊关节炎脑炎病毒（CAEV）从母体传播给后代主要是通过初乳和乳汁中的感染细胞介导的。母羊的感染通常是亚临床的，会导致乳汁中细胞增多，有时细菌共感染会加剧这种情况。虽然单核细胞是主要的病毒宿主细胞，但其他几种细胞类型，包括乳腺上皮细胞、成纤维细胞和内皮细胞，在体内的感染水平较低。然而，在体外，所有乳腺细胞表型对CAEV感染均高度敏感。这表明存在局部机制来控制病毒表达。我们的目标是分析调节局部病毒感染的机制，包括乳腺的生理状态和细菌共感染情况。在这项工作中，我们展示了一种利用基质胶中的三维培养物在体外重建乳腺组织模型的开发。将来自血液的单核细胞添加到体外三维培养物中。在这些实验条件下，乳腺细胞自发组织形成乳腺球。血液白细胞迁移到培养凝胶中，并特别定位于乳腺球的周边。如细胞病变效应和CAEV晚期抗原p30的表达所示，乳腺球在体外易受CAEV感染。该模型将允许对病毒表达、感染向乳腺细胞的转移以及乳腺细胞、感染的单核细胞和免疫活性细胞之间的相互作用进行体外研究。它将允许根据动物的生理和CAEV感染状态、微环境以及细菌共感染的存在，研究参与控制病原体进入乳汁的机制。
