Establishment and characterization of a new conditionally immortalized human astrocyte cell line

Abstract

Astrocytes are the most abundant cell types in mammalian brains, within which they participate in various neuronal activities, partly by utilizing the numerous transporters expressed at their plasma membranes. Accordingly, detailed characterization of astrocytic functions, including transporters, are essential for understanding of mechanistic basis of normal brain functions, as well as the pathogenesis and treatment of various brain diseases. As a part of overall efforts to facilitate such studies, this study reports on the establishment of a new human astrocyte cell line, which is hereafter referred to as human astrocyte/conditionally immortalized, clone 35 (HASTR/ci35). This line, which was developed utilizing a cell immortalization method, showed excellent proliferative ability and expressed various astrocyte markers, including glial fibrillary acidic protein. When cocultured with neuronal cells, HASTR/ci35 cells could facilitate their dendritic network formation. Furthermore, HASTR/ci35 cells not only possessed significant glutamate and adenosine transporter activities but also exhibited organic ion transporter activities. To summarize, HASTR/ci35 cells possess several key astrocytic characteristics, including various transporter functions, while simultaneously showing infinite proliferation and scalability. Based on these findings, HASTR/ci35 cells can be expected to contribute significantly to various human astrocyte study fields.

Functional Expression of Organic Ion Transporters in Astrocytes and Their Potential as a Drug Target in the Treatment of Central Nervous System Diseases

“…While there is no report showing the expression of OATP1B/Oatp1b members in astrocytes, recently Oatp1a4 and Oatp1a5 mRNA, and OATP2B1 mRNA expression has been reported in cultured rat and human astrocytes, respectively. 23,69) Moreover, OATP3A1 and 4A1 mRNA can also be detected in primary human astrocytes (unpublished observation). While characterization of their function in astrocytes awaits further studies, it is possible that the functions of such OATP members may contribute to the pharmacological action of both current and future CNS drugs.…”

“…[20][21][22] However, the absence of OCT3 expression in astrocytes has also been observed in some brain areas (such as the cerebellum), and primary human astrocytes are not always positive for OCT3 expression. 19,23) Therefore, OCT3 appears to be expressed in astrocytes heterogeneously.…”

“…24,31) Recently, however, evidence for PMAT's expression and functions (histamine and MPP + uptake) has been provided in primary and immortalized human astrocytes. 20,22,23) Therefore, it is probable that PMAT also serves as an astrocyte organic cation transporter.…”

“…This has been further supported by subsequent reports of OCTN2 in rats 40,41) and humans. 23) The presence of OCTN2 in astrocytes seems reasonable, since astrocytes require substantial amounts of energy to fulfill their roles. Panov et al 42) have hypothesized that, in line with the fact that perisynaptic processes of astrocytes hold large numbers of mitrochondria, 43) fatty acid β-oxidation is the preferable process for acetyl-CoA production, by which astrocytes accomplish large-scale production of lactate and ATP at the same time.…”

Temporal and Spatial Expression of LGR5 After Acute Spinal Cord Injury in Adult Rats

“…And then the glial scar provides a physical barrier to plasticity and regeneration, which might inhibit neuroplasticity [27,28]. Now that all of these are pernicious for neuronal regeneration and survival, it is essential and undoubted to control the astrocyte proliferation after SCI [29]. Besides, recognition of the involved proteins could be beneficial in assisting the regeneration of neurons Fig.…”