Propagation in culture

Despite such difficulties, at least one such inactivated product has reached clinical trials. The viral particles are initially propagated in cultured human T cells. They are then treated with formaldehyde to inactivate them — a process which also removes the viral envelope. The virion particles are then treated with y-irradiation in order to ensure inactivation of the viral genome. The final product is administered along with an adjuvant in order to maximize the immunological response (see later). 

Despite the negative results of feeding experiments, it is clear that animals require myo-inositol for the synthesis of phospholipids (see p. 175), and, perhaps, for other purposes. Indeed, jra/o-inositol is necessary for the propagation, in culture, of 19 out of 20 lines of normal and malignant human and mouse tissues.122 It thus appears likely that only certain animal... 

Goff SP, Berg P (1976), Construction of hybrid viruses containing SV40 and lambda phage DNA segments and their propagation in cultured monkey cells, Cell 9 695-705. 

Approximately a week after plating, all the normal (non-fused) B lymphocytes had already been eliminated naturally from the culture, because normal lymphocytes do not propagate in culture. Only those hybrids resulting from the fusion of the myelomas with the B lymphocytes were able to grow in the culture, and some of them also preserved the ability to secrete antibodies against the antigen used for immunization. 

Viral agents may be detected by direct observation of inoculated culture cells for cytopathic effects or by detection of antigens after incubation by immunofluorescent methods. The culture method is most useful for organisms such as cytomegalovirus (CMV) or herpes simplex virus because these viral agents are rapidly propagated in culture cells, making them easily detected. ... 

Two studies have used pseudotyped vesicular stomatitis virus (VSV) and rabies virus with CD4 and CXCR4 in place of their normal envelope proteins (Mebatsion et al., 1997 Schnell et al., 1997). This system targets a cytolytic virus to HIV-infected cells. While the rabies-virus pseudotype was only able to undergo a single round of infection, the VSV pseudotype could continue to propagate in culture, destroying HIV-infected cells. 

Addition of up to 200 ppm sulfur dioxide to grape musts is customary. Strains of S. cerevisiae and S. bayanus grown in the presence of sulfite, become tolerant of fairly high concentrations of SO2. Cultures propagated in the winery are added in Hquid suspension, usually at 1—2% of the must volume. Many strains are available in pure culture. Factors such as flocculence, lack of foaming, fast fermentation, lack of H2S and SO2 formation, resistance to sulfur dioxide and other inhibitors, and flavor production will affect strain choice. No strain possesses all the desired properties. 

The concentration of antibody in tissue cultures of the hybridoma is low (10-60"gml- ) but the use of large culture vessels can obviate this. The hybridoma can also be propagated in mice where the antibody concentration in the serum and other body fluids can reach lOrngml. ... 

Viral particles destined for use as vaccines are generally propagated in a suitable animal cell culture system. Although true cell culture systems are sometimes employed, many viral particles are grown in fertilized eggs or cultures of chick embryo tissue (Table 13.7). 

Several attenuated strains have been developed for use in vaccine preparations. The most commonly used is the Jeryl Linn strain, which is propagated in chick embryo cell culture. This vaccine has been administered to well over 50 million people worldwide and, typically, results in seroconversion rates of over 97 per cent. The Sabin (oral poliomyelitis) vaccine consists of an aqueous suspension of poliomyelitis virus, usually grown in cultures of monkey kidney tissue. It contains approximately 1 million particles of poliomyelitis strains 1,2 or 3 or a combination of all three strains. 

Young RC, Zhang P 2001 The mechanism of propagation of intracellular calcium waves in cultured human uterine myocytes. Am J Obstet Gynecol 184 1228-1234... 

McHale What is your view of action potential propagation in the uterus in vivo, rather than in cultured cells ... 

In order to prevent the unwanted drift of properties which might ensue from repeated subcultures or multiple generations, the production of biological medicinal products obtained by microbial culture, cell culture or propagation in embryos and animals should be based on a system of master and working seed lots and/or cell banks. 

---