Human serum albumin expression

We have isolated Rubisco small subunit promoters from several plant species and tested their strength with gusA and ALB (human serum albumin) transgenes in sprouts. The highest level of expression in Brassica napus sprouts has been obtained... 

Fig. 3.6 Human serum albumin (HSA) was produced during the sprouting of transgenic rape-seeds. A light-inducible Rubisco promoter was used to control transgene expression. The highest yield was obtained with light induction after three days of continuous darkness. Sprouting was carried out in an airlift fermentor at room temperature. The sprouting medium was water.

Human serum albumin was the first full-length human protein to be expressed in the leaves of a transgenic plant (both tobacco and potato leaves were shown to express the protein). This report was published in 1990 [18]. Four years earlier, Barta and colleagues had demonstrated the expression of human growth hormone in tobacco and sunflower callus, and the protein was expressed as a fusion with the Agrohacterium tumefaciens nopaline synthase enzyme [17]. 

Greiff [3.24] studied the stability of purified influenza virus of the strain PR 8 in physiological NaCl solution with calcium lactobionate and human serum albumin (each 1 % in the solution). The freezing rate was approx. 1 °C/min down to -30 °C. During the freeze drying, the product temperature was raised in 12 to 16 h from -30 °C to 0 °C and the product was dried at this temperature. After 24 h, the first 145 vials were removed, and additional vials after intervals of 24 h each. The residual moisture content was 3.0,2.0,1.5, 1.0 and 0.5 %. The stability of the freeze dried virus (expressed in days during which the titer of the infectivity decreased by a factor of 10 was most unfavorable at 0.4 % and 3.2 % RM, (4 and 7 days respectively at +10 °C) and best at 1.7 % RM 145 days or more than 1000 days at -10 °C. 

There have been several studies that underscore the importance of unbound concentration in cell-based studies of receptor function. In a model study of the effect of plasma protein binding on the renal transport of organic anions using the expression of various organic anion transporters (OATPs) in Xenopus oocytes, the transport of ochratoxin A, methotrexate, and estrone sulfate was found to be strongly inhibited by the addition of human serum albumin to the culture medium [16]. Similarly, the addition of oq-acid glycoprotein was found to reverse the blockade of sodium-ion current by cocaine in a preparation of cardiac myocytes [17]. 

Potato Potato tubers have been used extensively as the crop of choice in over three separate human cliiucal trials so far and have been utilized to produce vaccines, human serum albumin, TNF-a and various antibodies. However, since transgenic potatoes expressing the desired biopharmaceutical must be delivered in an uncooked form, they have been known to... 

Clinical trials have demonstrated excellent efficacy with recombinant human factor VIII concentrates available as Recombinate and Kogenate. These recombinant factor VIII products are purified from the cell culture of plasmids, not viral DNA-transfected hamster cells and therefore do not express viral sequences. The addition of human serum albumin for stabilization, constitutes the sole possible source for human viral contamination. More recently recombinant factor IX has been genetically engineered by insertion of the human factor IX gene into a Chinese hamster ovary cell line. It has been proved to be safe and effective in the treatment of patients with hemophilia B. 

Feedstocks of yeast cell suspensions are relatively common starting material, as the yeast cell usually exports the expressed recombinant protein efficiently in the culture medium. A process was developed for the recovery of human serum albumin produced in Pichia pastoris using a 5 cm diameter column run in expanded-bed mode and scaled up directly to a 100 cm diameter column using 150 liters of cationic exchangers. Using this size of column, it was possible to apply a 1900 liter cell suspension. The yield of human serum albumin varied from 83 to 91% over four different runs.22... 

The attempts at biopharming° are not restricted to transgenic cattle. Methods for the expression of pharmaceutically important proteins in plant cell cultures and in intact plants are showing promise (Moffat, 1991b). For example, tobacco and alfalfa plants have been shown to secrete antibodies, and human serum albumin has been produced in transgenic potatoes and tobacco. However, structural differences have been observed in the proteins produced in plants. Here again, issues of protein yields, and regulatory and safety concerns remain to be addressed. 

Some examples of research under development include a synthetic conjugated polysaccharide vaccine against Haemophilus influenzae type B, which has been described in 2004 (O Fig. 34). The vaccine prototype was obtained by conjugation to human serum albumin (HSA) [173]. Furthermore, very recently a malaria vaccine has been suggested [174] which is based on the total synthesis of the malaria toxin responsible for the morbidity and mortality associated with malaria. The malaria parasite expresses a large amount of glycosylphosphatidylinositol... 

Chloroplast expression Human serum albumin, 66.5 kDa, 585aa 11% TSP Tobacco leaves [18] ... 

Fernandez-San, M.A. Mingo-Castel, A. Miller, M. Daniell, H.A. A chloroplast transgenic approach to hyper-express and purify human serum albumin, a protein highly susceptible to proteolytic degradation. Plant Biotechol. 2003, /, 77-79. 

Expression of the human serum albumin gene is regulated by five transcription factors, four of which bind to the promoter region. 

Farran I, Sanchez-Serrano JJ, Medina JF, et al. Targeted expression of human serum albumin to potato tubers. Transgenic Res., 2002 11(4) 337-346. 

The first recombinant protein expressed in cultured plant cells was human serum albumin, produced in tobacco suspension... 

Recent work from our laboratory has dealt with human serum albumin (HSA) adsorption onto the conducting polymers PPyCl, PPyDS, and PPyTS [66] in an aqueous medium at pH 7.4. The PPy-HSA (1-2) interaction in water (w) can be expressed by... 

Cells were isolated from epididymal fat pads (3) of 5-7 weeks old Ivanovas mice and incubated in Krebs Ringer bicarbonate buffer containing various amounts of different cations and 3. 5% human serum albumin. Tlj media were kept isotonic and at pH 7. 4. The incorporation of U C D-Glucose into and total lipids was measured and used as an expression of glucose uptake (4). Results are expressed as uatoms glucose carbon incorporated into CO or total lipids, per gram total lipid weight, per 2 hours of incubation. 

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