Franceschini I A, Barnett S C
Department of Neurology, University of Glasgow, United Kingdom.
Dev Biol. 1996 Jan 10;173(1):327-43. doi: 10.1006/dbio.1996.0027.
Previously, we have shown that the O4 antibody can be used to define and purify olfactory nerve ensheathing cells (ONECs) from the rat olfactory bulb by fluorescence-activated cell sorting. In this study, using a larger panel of neural markers, we demonstrate that this apparently homogeneous population of ONECs possess a heterogeneous antigenic profile both in vivo and in vitro. The antigenic profile of the sorted cells initially correlated with their antigenic profile in vivo, although expression of some of the markers was either lost or gained during time in culture. These changes were influenced by the culture conditions, with a greater loss of "typical" ONEC markers in serum-containing medium. In serum-free medium, which maintains the cells in a phenotype that closely resembles their in vivo counterparts, we were able to reclassify the ONECs into two cell types based on morphology and antigenic phenotype by using antibodies to polysialic acid (correlating with the embryonic form of N-CAM expression) and the low-affinity nerve growth factor receptor. A detailed immunocytochemical study of the developing olfactory system showed that these two cell types could also be detected along the entire length of the olfactory nerve and the outer layer of the olfactory bulb from Embryonic Day 14 to adulthood, suggesting they were not an in vitro artefact. To address the relationship between the two cell types we constructed a clonal ONEC cell line by retroviral infection with the temperature-sensitive mutant gene of the large T antigen. This clonal cell line contained cells that expressed antigenic phenotypes of both classes of ONECs, suggesting that both cell types are related and share a common lineage.
此前，我们已经表明，O4抗体可用于通过荧光激活细胞分选从大鼠嗅球中定义和纯化嗅神经鞘细胞（ONECs）。在本研究中，我们使用了更多种类的神经标志物，证明了这群看似同质的ONECs在体内和体外都具有异质的抗原谱。分选细胞的抗原谱最初与其在体内的抗原谱相关，尽管某些标志物的表达在培养过程中要么丢失要么获得。这些变化受培养条件的影响，在含血清培养基中“典型”的ONEC标志物丢失得更多。在无血清培养基中，细胞维持着与体内对应细胞非常相似的表型，我们能够通过使用抗多唾液酸抗体（与N-CAM表达的胚胎形式相关）和低亲和力神经生长因子受体，根据形态学和抗原表型将ONECs重新分类为两种细胞类型。对发育中的嗅觉系统进行的详细免疫细胞化学研究表明，从胚胎第14天到成年，在嗅神经全长和嗅球外层也能检测到这两种细胞类型，这表明它们不是体外人工产物。为了研究这两种细胞类型之间的关系，我们通过用大T抗原的温度敏感突变基因进行逆转录病毒感染构建了一个克隆ONEC细胞系。这个克隆细胞系包含表达两类ONECs抗原表型的细胞，这表明这两种细胞类型相关且有共同的谱系。
