Recombinant bovine

U.S.A., in lactating dairy cattie to increase milk production. EH Lilly and Company, The Upjohn Company, and American Cyanamid Company also have interests in the commercial appHcation of recombinant bovine GH. Recombinant porcine GH [9061-23-8] preparations from several companies, eg. The Upjohn Company, Smith Kline Beecham Animal Health, Pitman-Moore, Inc., Monsanto Company, and American Cyanamid Company, are being evaluated for commercial use. Recombinant human GH for clinical use is marketed under such names as Protropin (Genentech), Umatrope (EH Lilly), Genotropin (Sumitomo), and Somatonorm (Kabi-Vitmm) by a variety of pharmaceutical companies. A listing of additional suppHers is available (2). 

One technology uses bovine somatotropin (bST) produced by recombinant technology (38). Somatotropin [9002-72-6] is a growth hormone. The bST-supplemented cows provide an increase in milk output per cow or an increased feed efficiency. Recombinant bST, also known as recombinant bovine growth hormone (rBGH) is the synthetic analogue of a natural hormone that increases milk production in cows (39). The use of recombinant technology was approved by the FDA in 1993. The Commission of the European Community has recommended that the moratorium on commercial use of BGH be delayed until the year 2000. 

Capper, J. L., Castaneda-Gutierrez, E., Cady, R. A., and Bauman, D. E. (2008). The environmental impact of recombinant bovine somatotropin (rbST) use in dairy production. Proc. Natl. Acad. Sci. USA 105, 9668-9673. 

Although most biopharmaceuticals approved to date are intended for human use, a number of products destined for veterinary application have also come on the market. One early such example is that of recombinant bovine GH (Somatotrophin), which was approved in the USA in the early 1990s and used to increase milk yields from dairy cattle. Additional examples of approved veterinary biopharmaceuticals include a range of recombinant vaccines and an interferon-based product (Table 1.7). 

Hagemann et al. [3.13] calculated the absorption isotherms for recombinant bovine Somatotropin (rbSt) and found 5-8 g water in 100 g protein, which was not only on the surface but also inside the protein molecule. 

Recognition site mapping, 10 326 Recombinant bovine somatotropin, 13 2 Recombinant CHO cell products... 

Steinbeck, M. J., Webb, D. S. A., Roth, J. A. (1989). Role for arachidonic acid metabolism and protein synthesis in recombinant bovine interferon- /induced activation of bovine neutrophils. J. Leuk. Biol. 46, 450-60. 

There are many examples of ELIS As used for detecting host cell impurities in the literature. Pauly et al.12 developed an ELISA to detect impurities in erythropoietin that had a detection limit of around 0.05 ng/ml. SDS polyacrylamide gel and Western blot analysis were used to confirm the spectrum of proteins detected and to demonstrate the specificity of the antibody preparation. Anicetti et al.14 describe an assay for the detection of E. coli proteins in recombinant DNA-derived human growth hormone. Whitmire and Eaton15 report on an immuno-ligand assay for quantitation of process-specific E. coli host cell contaminant proteins in a recombinant bovine somatotropin. 

Whitmire, M.L. and L.C. Eaton (1997). An immunoligand assay for quantitation of process specific Escherichia coli host cell contaminant proteins in a recombinant bovine somatotropin. J Immunoassay 18(1) 49-65. 

Recombinant bovine growth hormone (bovine somatotropin, BST)... 

In 1993, the FDA approved the use of recombinant bovine growth hormone (rbGH) in dairy cattle to increase milk production. Although milk and meat from rbGH-treated cows appear to be safe, these cows have a higher incidence of mastitis, which could increase antibiotic use and result in greater antibiotic residues in milk and meat. 

This polypeptide hormone constitutes one form of the recombinant bovine somatotropins used to increase milk production in dairy cows. Several studies have been performed in the United States, United Kingdom, and Germany to determine the concentrations of this drug in milk (99, 100). 

Figler, R. A., Graber, S. G., Lindorfer, M. A., Yasuda, H., Linden, J., and Garrison, J. C. (1996). Reconstitution of recombinant bovine Ai adenosine receptors in Sf9 cell membranes with recombinant G proteins of defined composition. Mol. Pharmacol. 50, 1587-1595. 

Vijay-Kumar, S. and Kumar, V.D. (1999). Crystal structure of recombinant bovine neurocalcin. Nat. Struct. Biol. 6 80-88. 

Hageman et al. [3.13] calculated the absorption isotherms for recombinant bovine somatotropin (rbSt) and found 5-8 g of water in 100 g of protein, which was not only on the surface but also inside the protein molecule. Costantino et al. [3.72] estimated the water monolayer M0 (g/100 g dry protein) for various pharmaceutical proteins and for their combination with 50 wt% trehalose or mannitol as excipient. They compared three methods of calculating MQ (1) theoretical (th) from the strongly water binding residues, (2) from conventional adsorption isotherm measurements (ai) and (3) from gravimetric sorption analysis (gsa) performed with a microbalance in a humidity-controlled atmosphere. Table 3.5 summarizes the results for three proteins. The methods described can be helpful for evaluating RM data in protein formulations. 

Chang, J. P Kiehl, D. E. Kennington, A. 1997. Separation and characterization of the tryptic peptide mapping of recombinant bovine growth hormone by reversed-phase high-performance liquid chromatography electrospray mass spectrometry. Rapid Commun. Mass Spectrom., 11, 1266-1270. 

Azzara, C.D., Dimick, P.S., Chalupa, W. 1987. Milk lipoprotein lipase activity during long-term administration of recombinant bovine somatotropin. J. Dairy Sci. 70, 1937-1940. 

Hormones are not allowed in organic production. This includes the range from the common milk letdown hormone (oxytocin) to lutylase which is used in conventional dairy to induce egg production by the ovary. Also prohibited of course is the use of the controversial growth hormone known as rBGH (recombinant bovine growth hormone). 

The molecular mechanisms by which the extension of the N-terminus by the extra methionine residue destabilized recombinant a-lactalbumin remain unclear. Additional conformational entropy of the extra methionine residue in the unfolded state could account for the destabilization and unfolding-rate acceleration of the recombinant protein [22]. Ishikawa and coworkers reported the destabilization of recombinant bovine a-lactalbumin, similarly induced by the extra N-terminal methionine residue, and showed that the enthalpy change of thermal unfolding was the same for the authentic and recombinant proteins, indicating that the destabilization was caused by an entropic effect [42]. However, the destabilization by the extra methionine residue in the lysozyme homologous to a-lactalbumin was rather enthalpic and accompanied by a disruption of hydrogen-bond networks in the N-terminal region [43,44]. 

Recent molecular cloning studies have identified aminopeptidase B as an appropriate Arg/Lys aminopeptidase (35). Molecular cloning of the bovine aminopeptidase B (AP-B) cDNA defined its primary sequence that provided production of specific antisera to demonstrate localization of AP-B in secretory vesicles that contain cathepsin L with the neuropeptides enkephalin and NPY. AP-B was also found in several neuroendocrine tissues by western blots. Recombinant bovine AP-B (35) and rat AP-B were compared. Recombinant bovine AP-B showed preference for Arg-MCA substrate compared with Lys-MCA. AP-B was inhibited by arphamenine, an inhibitor of aminopeptidases. Bovine AP-B showed similar activities for Arg-(Met)enkephalin and Lys-(Met)enkephalin neuropeptide substrates to generate (Met)enkephalin, whereas rat AP-B preferred Arg-(Met)enkephalin. Furthermore, AP-B possesses an acidic pH optimum of 5.5-6.5 that is similar to the internal pH of secretory vesicles. The significant finding of the secretory vesicle localization of AP-B with neuropeptides and cathepsin L suggests a role for this exopeptidase in the biosynthesis of neuropeptides. 

Recombinant bovine somatotropin, lysozyme Both the excipient type (sucrose, sorbitol, glycerol) and moisture content affected protein degradation [30]... 

C.L. Stevenson, M.J. Hageman, Estimation of recombinant bovine somatotropin solubility by excluded-volume interaction with polyethylene glycols, J. Pharm. Sci. 12 (1995) 1671—1676. 

Grobe, D. and Douthitt, R. 1995. Consumer acceptance of recombinant bovine growth hormone—Interplay between beliefs and perceived risks. Journal of Consumer Affairs 29 128-143. 

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