Hamster BHK

Herpes simplex (type 1 [1,3] hamster BHK cells infected with virus [1]) [1, 3]... 

Cells Chinese hamster CHO(SCl), CHO, V79, V79-4, DON, Cl-1, D-6 Syrian hamster BHK mouse 3T3, ME (mouse embryo primary cells) human HPBL (human peripheral blood lymphocytes), NHF (normal human fibroblasts), XP (xeroderma pigmentosum), FA (Fanconi s anemia), BS (Bloom s syndrome) Muntjac. Activation In experiments in which poor metabolizing ability of cells is augmented by an activation system S9 (Ames S-9 Mix), FL (irradiated feeder layer of metabolizing cells). 

Fig. 11.7 A, diagrammatic representation of plaque assay for evaluating virucidal activity and B, monolayers of baby hamster ki(hiey (BHK) cells C, virus tte untreated virus (o represents a plaque-forming unit, pfu, in BHK cells) D, virus titre disinfectant-treated virus (before plating onto BHK, die disinfectant must be neuh alized in an appropriate manner). Note the greatly reduced nimiber of pfu in D, indicative of fewer iminactivated virus particles than in C. 

For assaying herpes virus, monolayers of baby hamster kidney (BHK) cells are used. Virus titre is expressed as the number of plaque-forming units (pfu) per millilitre before and after exposure to a disinfectant, so that the virucidal efficacy of the test agent can be determined. A diagrammatic representation is given in Fig. 11.7. 

Many of the initial biopharmaceuticals approved were simple replacement proteins (e.g. blood factors and human insulin). The ability to alter the amino acid sequence of a protein logically coupled to an increased understanding of the relationship between protein structure and function (Chapters 2 and 3) has facilitated the more recent introduction of several engineered therapeutic proteins (Table 1.3). Thus far, the vast majority of approved recombinant proteins have been produced in the bacterium E. coli, the yeast S. cerevisiae or in animal cell lines (most notably Chinese hamster ovary (CHO) cells or baby hamster kidney (BHK) cells. These production systems are discussed in Chapter 5. 

Non-polarising BHK CHO Cos-1, Cos-7 HEK-293 (Baby) Syrian hamster kidney, fibroblast-like Chinese hamster ovary, fibroblast-like African green monkey kidney, fibroblast-like Human embryonic kidney, epithelial... 

Recently, it has been shown that cell-permeable cerantides dramatically inhibited the synthesis of the two major membrane phospholipids, PC and PE (Bladergroen et al, 1999b Allan, 2000). The inhibition of phospholipid synthesis was rapid, within 2 h, and resulted in massive apoptosis after 16-24 h. The mechanism by which short-chain cerantides exert their effect on phospholipid synthesis is possibly cell type dependent. In baby-hamster kidney (BHK) fibroblasts rc synthesis was reduced at the level of CT, the putative rate-determining enzyme in the CDP-choline pathway (Allan, 2000). This conclusion was based solely on radio-label studies in combination with an earlier published observation (Wieder et al, 1995) showing that C2-SM (the SM generated from C2-ceramide by SM synthase, which was actively synthesized in the BHK-cells) inhibited CT activity in vitro. On the other hand, data obtained from studies with rat-2 fibroblasts clearly showed that short-chain cerantides regulate the synthesis of PC and PE mainly at the final step of the CDP-pathways. This conclusion was based on the following observations (a) incorporation of [ H]-choline into PC and... 

Table 3.8. Expression systems that are/could potentially be used for the production of recombinant biopharmaceutical products (CHO=Chinese hamster ovary BHK=baby hamster kidney)...

Table 3.9. Some biopharmaceuticals currently on the market that are produced by genetic engineering in either E. coli or animal cells. CHO = Chinese hamster ovary cells BHK = baby hamster kidney cells...

Technical advances facilitating genetic manipulation of animal cells now allow routine production of therapeutic proteins in such systems. The major advantage of these systems is their ability to carry out post-translational modification of the protein product. As a result, many biopharmaceuticals that are naturally glycosylated are now produced in animal cell lines (Table 3.9). Chinese hamster ovary (CHO) and baby hamster kidney (BHK) cells have become particularly popular in this regard. 

Chinese hamster ovary (CHO) cells and baby hamster kidney (BHK) cell lines have been most commonly used, in addition to other cell lines, such as various mouse carcinoma cell lines. The recombinant factor VIII product generally contains only VIILC (i.e. is devoid of vWF). However, both clinical and pre-clinical studies have shown that administration of this product to patients suffering from haemophilia A is equally as effective as administering blood-derived factor VIII complex. The recombinant VIILC product appears to bind plasma vWF with equal affinity to native VIILC, upon its injection into the patient s circulatory system. Animal and human pharmacokinetic data reveal no significant difference between the properties of recombinant and native products. 

Cell transformation, Syrian hamster embryo cells, clonal assay Cell transformation, baby hamster kidney BHK-21 cells... 

Fig. 2. Effect of serum concentration on the attachment and spreading of BHK-21 cells onto TCP2 surface. BHK-21 cells were seeded in media containing the indicated concentrations of intact serum (open squares), Fn-depleted serum (triangles). Vn-depleted serum (circles), or serum-free medium alone (the single closed square) and the attachment panel (A) and spreading panel (B) of the cells were determined after 90 min culture on TCP (panel (A, B)) Mean SEM. (Reproduced from J. Biomed. Mater. Res. [Ref. 11 Role of serum vitronection and fibronectin in adhesion of fibroblasts following seeding onto tissue culture polystyrene] through the courtesy of John Wiley Sons, Inc.) BHK-21 Fibroblast cell lines from Baby Hamster Kidney 2 Similar results on Primaria are also presented in [Ref 11]...

Neoplastic transformation of fibroblastic cells has been reported with Chinese hamster lung cells, rat embryo cells, BHK cells, mouse 3T3 cell lines, a mouse ventral prostate cell line, and the mouse C3H/10T1/2 cell line (Heidelberger et al, 1983 Barrett and Ts o, 1978). The Syrian hamster embryo cells and the various mouse cell lines have been employed most often in studies employing fibroblastic cells. Neoplastic and preneoplastic transformation of normal human fibroblasts has also been reported in recent years (DeMars and Jackson, 1977, Freedman and Shin, 1977 Kakunagti, 1978 Milo and DiPaolo, 1978 Namba et al, 1978 Borek, 1980 McCormick et al, 1980 Sutherland et al, 1980 SilinskasetoiL, 1981). 

It is not known whether the transformation of Balb/c 3T3 cells is also a two-step process, like that in the other subtetraploid murine cell line, C3H lOTl/2. However, the results with the preneoplastic hamster cell line BHK are more consistent with a one-step process (Bouck and DiMayorca, 1976). 

Abbreviations. Ab, antibody SC, subcutaneous IV, intravenous CHO HSA, human serum albumin SC, subcutaneous USP, United States Pharmacopeia AHF IU, international unit NMT, not more than Ig, immunoglobulin BHK, baby hamster kidney PEG, polyethylene glycol hGH, human growth hoimone IM, intramuscular WFI, water for injection. 

---