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Our new Investigate Wall Chart is now available BioReliance has produced a new 'Investigate' wall chart with eye-catching images of adventitious agents and tests of interest to the biopharmaceutical industry. If you would like a FREE copy, please order via our literature request form. This section contains additional information on the items featured in our new Investigate Wall Chart (click for further information)
Intracisternal R-Type particles
Adenovirus Adenoviruses that effect humans are typically responsible for mild respiratory illness and conjunctivitis.
Aspergillus Aspergillus is the most common type of fungus found in the environment. There are over 185 species and approximately 20 of these are known to cause human disease. Infection by aspergillus is known as aspergilliosis, and is the 2nd most common fungal infection requiring hospitalization in the U.S. The two main mycotoxins produced by Aspergillus are ochratoxin and aflatoxin. Ochratoxin can damage the kidneys and liver. It has also thought to have a role in impairing immune function and is a suspected carcinogen. Aflatoxin is a potent carcinogen linked to a variety of human health problems. Early diagnosis of aspergillosis is important. PCR based testing for the detection of DNA specific for Aspergillus is the recommended method of confirming infection.
Baculovirus Bacululoviruses are used extensively in the drug industry for the efficient production of eukaryotic proteins. The viral genome is large and easy to manipulate, and the expressed proteins are often fully active and soluble. Additionally, the most commonly used baculuovirus for protein expression, Autographa californica, affects only two families of moth in nature. Although these viruses can enter other cell types, they are not infectious in them, so they are not thought to pose a significant hazard to laboratory staff or the environment.
Bovine Papillomavirus Systematic studies suggest that all mammals are infected by papillomaviruses (PV). Different papillomavirus types are designated “PV”, preceded by one or more letters indicating the species followed by a number whenever multiple PV types are found in the same host species. Papillomaviruses are usually responsible for skin lesions (warts) that are in most cases are benign and generally regress without any serious clinical problems in a host. In cattle, BPV can progress to cancer of the upper gastrointestinal tract and urinary bladder in animals exposed to bracken fern in the pasture. Bovine derived serum batches and products must be screened for this potential contaminant to ensure product safety.
Bovine Polyomavirus Polyomaviruses belong to the family polyomaviridae. These viruses have been referred to as small DNA tumor viruses because of their ability to transform established cell lines, to immortalize primary cell cultures and induce tumors in animals. Although potentially oncogenic, the viruses rarely cause disease in healthy individuals, but in immuno-compromised humans and animals the consequences can be serious. Members of the genus include Primate polymavirus SV40, Human polyomavirus JC and BK, Murine polymavirus, Hamster papovirus and Bovine polyomavirus (BPyV). BPyV was originally thought to be of simian origin but it was later shown to be of bovine origin, the primate cultures having been contaminated through the use of infected foetal bovine serum. This was of major significance to the biotechnology industry, as the presence of BPyV in serum batches poses a serious risk for the contamination of human therapeutic products. The virus has been the focus of increasing regulatory concern due to its reported presence in a high proportion of bovine serum together with indications that BPyV is zoonotic (naturally transmitted between vertebrate animals and humans). Recent European guidelines state that “Serum manufacturers and users are encouraged to apply infectivity assays for BPyV in order to limit or eliminate infectious virus from batches of serum.” The FDA is also involved in discussions regarding the risks associated with polyomaviruses in vaccine substrates. [The European Agency for the Evaluation of Medicinal Products, Evaluation of Medicines for Human Use. July 2003. Note for Guidance on the Use of Bovine Serum in the Manufacture of Human Biological Medicinal Products (CPMP/BWP/1793/020].
Bovine Viral Diarrhea Virus (BVDV) BVDV causes a number of serious diseases in cattle resulting in large annual losses to the cattle industry. The virus can pass across the placental membrane of infected cows to the unborn calf, causing abortion or infants that die early in life. However calves that survive the infection remain carriers and can pass on the virus to other members of the herd. The virus can spread quickly unless action is taken to isolate the infected animals. BVDV is a common contaminant of bovine derived biological products such as foetal bovine serum, and can lead to further contamination of biological products in the laboratory. Image captured by a BioReliance scientist. For more information, contact marketing@bioreliance.com
Bunyavirus Bunyaviridae encapsulate over 330 known species, approximately 60 of which cause disease in humans. Infection in humans usually results from accidental transmission via an insect bite. Although most cause relatively minor disease, some can be deadly. Diagnosing bunyavirus infections quickly is important and in the laboratory there are several options available such as viral isolation via sensitive cell culture systems, specific IgM antibody detection and a variety of serological techniques including HI, CFT, IFA, neutralization tests and ELISAs. Animal derived products carry the risk of potential infection and must be suitably tested to ensure product safety.
Comet assay The Comet assay, also known as single gel electrophoresis (SCG), is a microgel DNA electrophoresis technique that detects DNA damage and repair in individual cells. The damage is represented by an increase of DNA fragments that have migrated out of the cell nucleus, which under fluorescence form a distinctive comet tail. The length and fragment content of the tail is directly proportional to the amount of DNA damage. The assay is conducted in both in vitro and in vivo test systems and is increasingly being used in genotoxic testing of industrial chemicals, agrochemicals and pharmaceuticals. For further information on BioReliance's Comet services, please click here.
Encephalomyocarditis (EMC) Virus Encephalomyocarditis virus is a widely distributed picornavirus that infects many animal species and humans. Pigs are the most commonly and severely infected domestic animals and EMCV is endemic in many pig populations. Studies indicate that EMCV causes interspecies infections, making it an important zoonotic agent.
Fluorescence in situ hybridization (FISH) Fluorescence in situ hybridization (FISH) allows the chromosomal location of recombinant DNA sequences inserted into a cell line to be determined. If more than one site is present it allows determination of the relative distribution of the sequences between those sites. In parallel with copy number determination and DNA sequencing carried out by Molecular Biology, it allows the stability of the inserted DNA sequences to be confirmed. The image displays genomic DNA hybridized to CHO chromosomes.
Flavivirus The family Flaviviridae contains approximately 69 pathogens, many of which cause serious disease in humans. The International Committee on the Taxonomy of Viruses divides flaviviridae into 3 genera; flavivirus, pestivirus and hepacivirus. The flavivirus genus alone includes yellow fever virus, dengue fever virus, and Japanese encaphilitis virus. All viruses in the flavivirus genus are transmitted by arthropods, and one of the key features of the transmission is that the viruses are able to reproduce in their vector. Without that ability, the viruses would not remain viable and able to transmit from host to host. Despite the large number of viruses in the family, only a relatively small number of vaccines have been developed to control human flavivirus diseases. Live attenuated vaccines have been developed and licensed for yellow fever (strain 17D) and Japanese encephalitis (strain SA14-14-2). The yellow fever live attenuated 17D vaccine has been particularly successful and has been used to inoculate over 300 million people worldwide. With such potential, flaviviruses remain a topic of high interest in the drug industry with a number of experimental vaccines in development.
Herpes Simplex Virus Herpes infections are reported to be the most common viral infections in humans. After the initial infection the virus becomes latent, persisting in ganglia at the foot of the brain, but can re-emerge and produce a fever-blister given the right conditions. This can vary but is typically when the host is under stress. Adenovirus and herpesvirus viral vectors are among the most commonly used in the pharmaceutical industry.
Mycoplasma Mycoplasma is the smallest, self replicating organism known to exist. Nicknamed “crabgrass” for its persistant infection, which is difficult to detect, diagnose and cure, more than 100 distinct species have been identified to date. Therapeutic products for human or veterinary use require mycoplasma screening at a variety of stages in their production, such as: cell banking, virus seed stock preparation, unprocessed bulk harvesting, raw material use, & final product release. Due to their small size and lack of cell wall, mycoplasmas can occasionally penetrate laboratory filters and accidental cross-contamination can occur. Mycoplasma cell culture contamination can be a serious problem for the biopharmaceutical industry, compromising the safety of the product and resulting in expensive withdrawals. All animal species from which biological products are derived are known to harbour mycoplasma infections. According to Hay et al, an estimated 5-35% of cell cultures worldwide are contaminated with at least one species of mycoplasma 1. [Hay, RJ, Macy and Chen, TR. Mycoplasma Infection of cultured cells. Nature ( London), 339: 487-488, 1989 ] DNA flurochrome staining is fast, sensitive and allows frequent testing at each passage. Typically, a cell sheet between 50-80% confluent is fixed and stained with the DNA specific dye and examined under fluorescent microscopy. Non nuclear staining and contaminants stand out boldly against a black background. Several DNA fluorochromes can be used in the same technique but none of them are thought to perform as well as Hoechst staining.
Parapoxvirus Parapoxvirus is responsible for contagious ecthyma (Orf or “sore mouth”) in sheep and goats. This can lead to a loss of condition as animals will often refuse to feed. It is extremely contagious and the virus can be passed on to humans working with infected animals.
Paramyxovirus Viruses in the Paramyoviridae family are responsible for a variety of clinical illnesses in humans, including measles and mumps. Parainfluenza viruses are included in this family and cause respiratory disease. Image captured by a BioReliance scientist. For more information, contact marketing@bioreliance.com
Porcine Circovirus Ciroviruses are considered pathogens in plants, birds and mammals. In pigs they have been linked to a variety of illnesses and pose a serious threat to production. The problem is somewhat compounded by the fact that not all infected animals show disease symptoms Porcine derived products are a potential route for circovirus infection in humans and it is important that all products are screened for possible contamination. There has been a lot of recent interest in porcine circoviruses due to continuing high-profile research on xenotransplantation.
Protozoa Protozoa are unicellular organisms that in terms of number and biomass could easily be considered one of the most abundant on Earth. There are currently 60,000 known species with sizes typically ranging from 10-200 µm. One of their important functions in the global ecosystem is to consume bacteria. They are also considered to have important roles as parasitic and symbiotic organisms in multicellular organisms. Protozoa infections in humans are typically via an insect bite. Inside the body, rather than being consumed by white blood cells, they multiply within them and the infection spreads. The infections can result in a number of serious illnesses, collectively known as leishmaniasis. At any one time around 20 million people in the world are thought to be suffering from protozoal infection. Perhaps due to their abundance and diversity, protozoa are occasionally found as contaminants in cell lines and animal derived products.
Cross-reactivity testing Cross-reactivity studies are used to determine whether an antibody for medicinal or diagnostic use displays any ‘unintentional’ binding (other than to the target antigen) in a range of human tissues. The testing is a regulatory requirement for the pre-clinical characterization of therapeutic and diagnostic antibodies. Cross-reactivity studies with human tissues or cells, where applicable, should always be conducted prior to Phase 1 clinical studies. For further information on cross-reactivity testing services at BioReliance, please click here.
Tectivirus Tectiviridae are bacteriophages (phages), viruses that infect bacteria. When they were discovered after WW1 it was hoped that their ability to kill bacteria could be used for the prevention and treatment of bacterial disease, but this was not successful due to the development of resistant bacteria (Goyal et al 1987). However phages are often used as a useful model for human viruses. In the pharmaceutical industry, phages are a potential threat to bacterial cell lines and steps must be taken to avoid introducing such contaminants during production.
Transformed SHE cells The Syrian hamster embryo (SHE) cell transformation assay is an in vitro test for carcinogenic potential based on the ability of a substance under test to cause morphologic transformation of the SHE cells. Normal colonies contain cells with an organised pattern of growth with minimal cell criss-crossing, and tend to be in a monolayer. Transformed colonies contain cells arrayed in an extensive, randomly orientated, three dimensional stacked growth pattern with criss-crossing of cells at the perimeter and in the interior of the colony. Cells in morphologically transformed colonies frequently are more basophilic than their normal counterparts and have increased nuclear/cytoplasmic ratios. (Isfort et al, 1994). Under the strategy for testing the carcinogenic potential of a pharmaceutical, the ICH Harmonised Tripartite Guideline A1B indicated that data from in vitro assays, such as a cell transformation assay, can be useful at the compound selection stage. This has triggered an interest from regulatory agencies for using the SHE cell transformation assay to test a genotoxic pharmaceutical, especially if the drug is intended to be administered chronically to a human. For further details on SHE cell assays at BioReliance, please click here.
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