Cell line storage

For cell line storage, a cell bank is generally established, with initially three to five flasks. One of these flasks is then thawed and the cell population is expanded to produce a master bank with about 10 to 20 flasks, depending on future requirements. 

Martiniuk, F., Chen, A., Donnabella, V. et al. (2000) Correction of glycogen storage disease type II by enzyme replacement with a recombinant human acid maltase produced by over-expression in a CHO-DHFR(neg) cell line. Biochemical and Biophysical Research Communications, 276 (3), 917-923. 

Once in the serum, aluminium can be transported bound to transferrin, and also to albumin and low-molecular ligands such as citrate. However, the transferrrin-aluminium complex will be able to enter cells via the transferrin-transferrin-receptor pathway (see Chapter 8). Within the acidic environment of the endosome, we assume that aluminium would be released from transferrin, but how it exits from this compartment remains unknown. Once in the cytosol of the cell, aluminium is unlikely to be readily incorporated into the iron storage protein ferritin, since this requires redox cycling between Fe2+ and Fe3+ (see Chapter 19). Studies of the subcellular distribution of aluminium in various cell lines and animal models have shown that the majority accumulates in the mitochondria, where it can interfere with calcium homeostasis. Once in the circulation, there seems little doubt that aluminium can cross the blood-brain barrier. 

Idursulfase (Elaprase) is a drug used to treat mucopolysaccharidosis II or Hunter syndrome. It is a lysosomal storage disease caused by iduronate-2-sulfatase deficiency. Idursulfase is a purified form of iduronate-2-sulfatase produced by recombinant DNA technology in a human cell line. The drug provides clinically important benefits to Hunter syndrome patients. After intravenous infusion Idursulfase is eliminated by peptide hydrolysis with an elimination half-life of 45 minutes. The most common adverse events are hypersensitivity reactions, pyrexia, headache and arthralgia. 

Speck, P., F. Escher, and J. Solms. Effect of salt pretreatment on quality and storage stability of air-dried carrots. Lebensm Wiss Technol 1977 10 308. Widholm, J. Selection and characterization of a Daucus carota cell line resistant to four amino acid analogs. J Exp Bot 1978 29 1111. 

Administration of triply, 3C-labelled (5)-reticuline to a stable variant non-alkaloid producing cell culture line of Thalictrum tuberosum in cell culture demonstrated a very high incorporation of label into protoberberine alkaloids that were subsequently produced. Since this cell line does not produce reticuline, because the cell line lacks or has insufficient quantities of three methyltransferases that lead to the formation of reticuline, cell cultures that contain this cell line are appropriate for the study of biosynthetic studies., 3C NMR spectroscopy and CIMS were utilized to follow the time course of the metabolism, and demonstrated the rapid formation of scoulerine as a primary reaction product, followed by further tetrahydroprotoberberines and dehydroprotoberberines. The apparently reversible formation of dehydroscoulerine in significant amounts was interpreted as evidence for the role of this compound as an alkaloidal storage product from which scoulerine may be regenerated via enzymic reduction. Scoulerine, dehydroscoulerine, columbamine, and (S)-reticuline were detected by l3C NMR in the crude extracts, while berberine was detected by HPLC. The biosynthetic pathway of these protoberberines in this variant cell culture were summarized as follows [151] (S)-reticuline > scoulerine -> tetrahydrocolumbamine (hypothetical) -> columbamine -> dehydroscoulerine -> candadine -> berberine. 

A preliminary investigation was made of the toxicity of the graft copolymer emulsion using human erythrocytes as a model cell line. First of all the toxicity of an emulsion prepared from 5% HEMA and 1% alginate in phosphate buffered saline was estimated by examination of a mixture with 10% hematocrit after 1 h storage. No lysis could be observed and the cells could be separated and disrupted in distilled water. We then encapsulated 10% hematocrit in the same emulsion and stored the capsules in isotonic saline for one week. The cells were recovered by disruption of the capsules with citrate and were perceived as healthy as per the simple tests outlined above. 

---