Serum, cell culture

J. P. Mathei, ed.. Mammalian Cell Culture The Use of Serum-Free Hormone-SupplementedMedia, Plenum Press, New York, 1984. 

Imidazole antimycotics, ketoconazole, clotrimazole, and miconazole are potent inhibitors of various cytochrome P450-isoenzymes that also affect the metabolism of retinoids. They were fust shown to inhibit the metabolism of RA in F9 embryonal carcinoma cells. When tested in vitm liarazole, a potent CYP-inhibitor, suppressed neoplastic transformation and upregulated gap junctional communication in murine and human fibroblasts, which appeared to be due to the presence of retinoids in the serum component of the cell culture medium. Furthermore, liarazole magnified the cancer chemopreventive activity of RA and (3-carotene in these experiments by inhibiting RA-catabolism as demonstrated by absence of a decrease in RA-levels in the culture medium in the presence of liarazole over 48 h, whereas without liarazole 99% of RA was catabolized. In vivo, treatment with liarazole and ketoconazole reduced the accelerated catabolism of retinoids and increased the mean plasma all-irans-RA-concentration in patients with acute promyelocytic leukemia and other cancels. 

Historically, the development of animal cell culture systems has been dependent upon the development of new types of tissue culture media. Mouse L cells and HeLa cells were developed using a balanced salt solution supplemented with blood plasma, an embryonic tissue extract, and/or serum. In 1955 Eagle developed a nutritionally defined medium, containing all of the essential amino acids, vitamins, cofactors, carbohydrates, salts, and small amounts of dialyzed serum (Table 1). He demonstrated that this minimal essential medium (MEM) supported the long-term growth of mouse L and HeLa ceils. Eagle s MEM was so well defined that the omission of a single essential nutrient eventually resulted in the death of these animal cells in culture. 

A standardized viral suspension is exposed, in the presence of yeast suspension, to appropriate dilutions of disinfectant in WHO hard water. At appropriate times, dilutions are made in inactivated horse serum and each dilution is inoculated into tissue cell culture or embryonated eggs (as appropriate for the test virus). The drop in infectivity of the treated virus is compared with that of the control (untreated) virus. 

In this in vitro system, the presence of serum in cell culture medium is not necessary, but the type of transwell is important (the total amount of H-triglycerides secreted was two-fold higher when using 3 pm versus 1 pm pore size transwells), and oleic acid supplementation is required for the formation and secretion of CMs as well as the transport of 3-carotene through Caco-2 cells. Finally, the presence of Tween 40 does not affect CM synthesis and secretion in this in vitro cell culture system. Thus, CMs secreted by Caco-2 cells were characterized as particles rich in newly synthesized H-triglycerides (90% of total secreted) containing apolipoprotein B (30% of total secreted) and H-phospholipids (20% of total secreted) and with an average diameter of 60 nm. These characteristics are close to those of CMs secreted in vivo by enterocytes. ... 

Over a long time period it may well not be possible to duplicate library cell culture conditions. What happens when the lot of media used in the final culture step prior to pyrolysis has been consumed Can culture media suppliers assure nutritional identity between batches Media types for growth of fastidious strains invariably include natural products such as brewer s yeast, tryptic soy, serum, egg, chocolate, and/or sheep blood. Trace components in natural products cannot be controlled to assure an infinite, invariable supply. The microtiter plate wells used here do not hold much media. Even so, the day will come when all media supplies are consumed and a change in batch is unavoidable. When that happens, if there were no effective way to compensate spectra for the resulting distortions, it would be necessary to re-culture and re-analyze replicates for every strain in the reference library. Until recently the potential for obsolescence was a major disincentive for developing PyMS spectral libraries of bacteria. Why this is no longer an insurmountable problem is discussed in the next section. 

Lin C-Y, Huang C-S, and Hu M-L. 2007. The use of fetal bovine serum as delivery vehicle to improve the uptake and stability of lycopene in cell culture studiefi.Br J Nutr 98 226-232. 

HyClone is a supplier of cell culture and bioprocessing systems, which also offers customized work to configure particular applications. Services address activities, research, and production. Business is centered on culturing media, and consequently support is offer for the development of a given formulation. HyClone supplies FBS and other sera for cell culture, serum-free and protein-free media, etc. 

RKO cells were cultured in DMEM medium (high glucose) supplemented with fetal bovine serum and antibiotics (Invitrogen) in eight 150 x 25 mm cell culture dishes to 50 to 60% confluency. Upon removal of... 

Fig. 2.2 Stability of IgCi monoclonal antibody added to sterile plant and animal cell culture media. ( ) Murashige and Skoog (MS) medium (A) Dulbecco s minimal essential medium (DMEM) with 10% serum and (A) serum-free Ex-cell 302 medium. The error bars indicate standard errors from triplicate flasks. (Reproduced with permission, from B. M. -Y. Tsoi and P. M. Doran, Biotechnol. Appi. Bio-chem. 2002, 35, 171-180. Portland Press on behalf of the IUBMB.)...

Although plant cell culture is not as cost effective as plant cultivation in the open field, it will become an economical process if higher protein yields can be achieved [58]. The cultivation medium of plants is chemically defined, consisting of a carbon source, minerals, vitamins and phytohormones [69]. Furthermore, it is protein-free and relatively inexpensive. In contrast, animal cells often require complex supplements such as fetal calf serum and/or expensive growth factors, although serum-free cultivation is possible in case of Chinese hamster ovary (CHO) cells [70]. 

Mammalian cell culture is more technically complex and more expensive than microbial cell fermentation. Therefore, it is usually only used in the manufacture of therapeutic proteins that show extensive and essential post-translational modifications. In practice, this usually refers to glycosylation, and the use of animal cell culture would be appropriate where the carbohydrate content and pattern are essential to the protein s biological activity, its stability or serum half-life. Therapeutic proteins falling into this category include EPO (Chapter 10), the gonadotrophins (Chapter 11), some cytokines (Chapters 8-10) and intact monoclonal antibodies (Chapter 13). 

In addition to protein impurities emanating directly from the source material, other proteins may be introduced during upstream or downstream processing. For example, animal cell culture media are typically supplemented with bovine serum/foetal calf serum (2-25 per cent), or with a defined cocktail of various regulatory proteins required to maintain and stimulate growth of these cells. Downstream processing of intracellular microbial proteins often requires the addition of... 

The use of triphenylethylene SERMs as Pgp inhibitors for clinical application has been hampered by unacceptable toxicity at doses required to achieve adequate cellular concentration, which is likely due to the involvement of proteins with the ability to bind these compounds. For instance, toremifene is able to reverse MDR and to sensitize human renal cancer cells to vinblastine in vitro. However, in vivo toremifene is tightly bound to serum proteins, in particular a 1-acid glycoprotein (AAG), which may limit its tissue availability (Braybrooke et al. 2000). In agreement with this, Chatterjee and Harris (1990) have shown that tamoxifen and 4-OH-tamoxifen were similarly potent in reversing MDR in Chinese hamster ovary (CHO) cells with acquired resistance to adriamycin. However, the addition of AAG (0.5 to 2 mg/ml, the range found in vivo) to cell cultures decreased the effect of tamoxifen on reversing MDR, and at the highest AAG concentration there was a complete reversal of the effects of... 

In rat blood and in the cell culture medium RPMI 1640 (+15% fetal calf serum) oxaliplatin (4) forms the major biotransformation products [Pt(dach)Cl2], [Pt(dach)(H20)Cl]+ (only in plasma ultrafiltrate), and [Pt(dach)(methionine)]+ (91). 

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