Cell cultures vaccine testing

A more general example from virus vaccine production is the rigorous examination of tissue cultures to exclude contamination with infectious agents from the source animal or, in the cases of human diploid cells or cells from continuous cell lines, to detect cells with abnormal characteristics. Monkey kidney cell cultures are tested for simian herpes B virus, simian virus 40, mycoplasma and tubercle bacilli. Cultures of human diploid cells and continuous line cells are subjected to detailed kary-ological examination (examination of chromosomes by microscopy) to ensure that the cells have not undergone any changes likely to impair the quality of a vaccine or lead to undesirable side-effects. 

Poliomyelitis (live or oral) (Sabin type) Cell cultures infected with attenuated poliovirus of each of the three serotypes 1 Clarification 2 Blending of virus of three serotypes in stabilizing medium Infectivity titration of each of three virus serotypes Test for attenuation by Inoculation of spinal cords of monkeys and comparison of lesions with those produced by a reference vaccine... 

Abstract. The hybrid cell lines, which we have obtained, can be widely used in veterinary virology and biotechnology for preparing vaccines, test-systems for viruses. Any strains of hybrid cells are producing the biological active proteins (enzymes and others). We have obtained hybrid cell lines (PO-TKxCO, PO-TKxHO), which are sensitive to prion protein, and also hybrid culture with P-cells of the pancreas of rabbit. 

The norms for medicinal production are particularly stringent. Biological products are composed of complex molecules, produced by cell lines with a relatively recent history, and difficult to characterize. Tests performed only on the final product do not guarantee consistency of production. The purification procedures should be planned and validated for the removal of potential contaminants from diverse sources cells, culture media, equipment, and reagents used in the purification or even degradation products derived from the protein itself. There are examples of products with unexpected risks that have caused serious problems such as blood contamination by HIV-1 virus between 1980 and 1985 (Bloom, 1984) or the presence of residual infectious viruses in the poliomyelitis vaccine due to inefficient inactivation (Lubiniecki et al., 1990). 

Cell culture is the predominant and indispensable tool for virus isolation and cultivation infectivity assays and vaccine production and testing. Although some viruses are more easily isolated in animals and embryonated eggs, the modem era of virology only began when Enders et al. (1949) showed that poliovirus was able to reproduce in various kinds of human embryonic cells in culture whereas in vivo its multiplication is largely restricted to the neurons in the grey column of the spinal cord. 

The major concerns with vaccine production are firstly, is the virus harmless and secondly is the vaccine free of adventitious agents. If the vaccine is produced from a virulent virus it is essential that the virus is completely inactivated before vaccine distribution. If attenuated strains are used the stability of the attenuation must be monitored. In both cases cell cultures are used in tests. 

An example of the role(s) that primate research has played is in the development of the poliomyelitis vaccines. Although many studies on poliomyelitis in humans were conducted in the late nineteenth century, the cause of the disease remained unknown until scientists succeeded in transmitting the virus to monkeys in 1908. There followed many years of research with primates until scientists were able, in the early 1950s, to grow the virus in human cell cultures and development of a vaccine became possible. At that point in time, in order to ensure the safety and effectiveness of the vaccines, tests were conducted with monkeys. Furthermore, in order to produce the vaccines in pure form in great quantities, it was necessary to use kidney tissue taken from monkeys. Today, an alternative to the use of monkey kidneys has been developed for the production of the vaccine. 

Bunyak, E.B. Hilleman, M.R. Weiber, R.E. Stokes, J., Jr. Live attenuated rubella virus vaccines prepared in duck embryo cell culture. I. Development and clinical testing. J. Am. Med. Assoc. 1968, 204, 195-200. 

C. Prophylaxis/Vaccine. Investigational vaccines are currently being tested. An experimental vaccine, designated TC-83 is a live, attenuated cell-culture-propagated vaccine. A second investigational product that has been tested in humans is the C-84 vaccine, prepared by formalin-inactivation of the TC-83 strain. 

Because of the declining potency of the existing smallpox vaccines and continued concerns about the prospect of the use of variola virus in biological warfare, a new vaccinia vaccine is in clinical testing by the U.S. Army Medical Research and Materiel Command, Fort Detrick, Frederick, Maryland. This vaccine was derived from a NYCBOH strain of vaccinia and then produced in human diploid lung fibroblast cell cultures. Unlike calf-lymph vaccines, this cell culture-derived vaccinia vaccine contains no adventitious agents. 

Maire LF III, McKinney RW, Cole FE Jr. An inactivated eastern equine encephalomyelitis vaccine propagated in chick-embryo cell culture, I Production and testing. Am J TropMed Hyg. 1970 19(1) 119 122. 

Whooping-cough (Pertussis) (aceiiuiar)t Cultures of Bord. pertussis 1 Harvest 2 Extraction and blending of cell components As for whole-cell whooping-cough vaccine Weight gain test in mice to exclude excess toxicity... 

Some experimental information consistent with our hypothesis exists. V. Vonka and co-workers at the Institute of Sera and Vaccines in Prague, were able to induce up to 300% increase in the number of Epstein Barr virus (an oncogenic Herpes type virus) positive cells in a culture of Burkitt lymphoma cells (EB 3) by treatment with d,y-dichlorodi am mi ncpl ati num( 11). The induction of the new, virus-associated antigens was monitored both by an indirect immunofluorescence test for the coat proteins of the virus appearing at the cell surface, and by the visualization of virus-like particles in the treated cells by electron microscopy. 

Nonviable cells of S. faecalis strain N were used for the immunization of rabbits to activate the immune system to synthesize antibodies. To prepare the vaccine, the cells from 500 mL of freshly grown culture were collected by centrifugation at 10,000 rpm and then shaken in 100 mL of 0.2% formaldehyde in saline for 48 h. After removal of the formaldehyde by washing the cells with 0.01 M phosphate buffer of pH 7.2 in saline, the cells were suspended in 80 mL of sterile saline. Viability tests showed that the cells were made nonviable by this treatment. This suspension exhibited high absorbance at 600 nm and was used for immunizing rabbits. 

Animal cells in culture have been widely used to study the physiology, metabolism, and biochemistry of cells test the effect of compounds on different cell types in tissue engineering applications and for the production of recombinant glycoproteins, viral vaccines, and... 

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