The Ames Test (Bacterial Reverse Mutation test) provides a simple,
straight-forward measure of the mutagenicity of small molecule formulations of pharmaceuticals, cosmetics, flavors & fragrances, consumer products, veterinary products, impurities and more.
At Inotiv, we offer the most comprehensive array of methods, designs, and options for Ames Tests, including:
*Also available in EpiDerm™ 3D Reconconstructed Human Skin (RSMN Assay)
The micronucleus assay is ideal for use as a follow up assay to explore mechanism of action (aneugenic or clastogenic) from an initial genotoxicity result. Either FISH or CREST techniques may be used without the need to interrogate additional cells beyond the basic assay design.
The in vivo micronucleus assay is a short-term cytogenetic assay for detecting agents that induce chromosomal breakage or spindle malfunction. Femoral bone marrow or peripheral blood is evaluated either microscopically or by flow cytometry for the presence of polychromatic erythrocytes containing micronuclei.
Inotiv provides insights through a cost-effective, non-GLP genetic toxicology screening program that is designed to quickly determine the genotoxic potential of your substance. Our approaches include:
Early identification of potential genotoxic issues with candidate compounds is an essential part of a product development process.
When designing a screening program, various factors need to be considered including: the purpose of the testing (e.g. prediction of GLP assays or investigation of mechanism of action), how the data will be used, the quantity of test article available, cost and timeline.
Inotiv provides testing using the Multiflow™ assay which can determine mode of action and genotoxicity. The Multiflow™ can provide information on which MOA is present therefore providing definitive information on whether or not a substance is genotoxic and whether or not it should be continued for development.
MultiFlow™ is a high-throughput 96-well assay using human TK6 cells. and Litron’s MultiFlow™ DNA Damage Kit. The assay uses a combination of machine learning and global evaluation factor models to predict the clastogenic, aneugenic, or non-genotoxic properties of test articles based on patterns of test article-induced changes in p53, γH2AX, Phospho-Histone H3 biomarkers and polyploidy. This assay is used to predict genotoxic properties as well as Mode of Action (MOA) of test articles in one single assay, a feature which is not found in other screening assays. Moreover this assay provides concurrent analysis of multiple biomarkers (p53, γH2AX, Phospho-Histone H3) and thus avoids the limitations of predictions of a single assay or biomarker. A test compound can be classified as a clastogen, aneugen, or non-genotoxicant. Identification of a clastogenic MOA means that the compound is likely DNA reactive with a linear dose response. No exposure or, at best, very low exposure is considered safe; and further product development may not be advisable. On the other hand, an aneugen MOA means that the compound is likely non-DNA reactive and that there may be a threshold response and a margin of safety that allows for the compound to continue in development. A classification of non-genotoxicant could mean the product is safe for further development. The high through-put design has short turn-around times using minimal amounts of test article. The MOA information can also be used for designing GLP assays in a smarter way to avoid costly and time consuming follow-up assays.
These assays are smaller versions of the GLP assays and therefore require much smaller amounts of test article and can be performed in less time and for less money.
Inotiv offers Quantitative Structure–Activity Relationship (QSAR) as an in silico method for predicting chemical substances causing adverse effects based on their chemical structures. Our expert rule and statistical-based models include:
Quantitative Structure Activity Relationship (qSAR) involves in silico methods designed to find relationships between chemical structure and biological activity of compounds from both in vivo and in vitro assays. This tool is a primary step in lead candidate selection and is useful in pharmaceutical development, agricultural and industrial chemical assessment, and impurity analysis. QSAR models include those for bacterial mutagenicity models for ICH M7 guidelines, carcinogenesis, and various types of organ-specific toxicities. Since in silico analyses do not require synthesis of the chemical of interest, they provide a cost and time effective approach to early screening.
Studies have shown that 29% of marketed drugs contained positive findings in one of the four categories of standard battery assays (bacterial mutation, in vitro mammalian cell gene mutation, in vitro and in vivo cytogenetics). For these reasons, a range of approaches are available to assess the relevance of a positive genotoxicity result. While there are techniques such as QSAR and FISH/CREST to assess whether a positive result is real, if indeed these techniques result in a real positive, follow-up assays can be conducted to further define the biological relevance of the result.
The Comet Assay, also called single cell gel electrophoresis, is a rapid and sensitive technique for accurately analyzing DNA damage (genotoxicity) in individual cells from small molecule formulations of industrial chemicals, consumer products, agrochemicals, and pharmaceuticals. The Comet Assay is a common follow up to a positive in vitro assay (such as the chromosome aberration and/or in vitro micronucleus assay).
The Comet Assay can be used to detect multiple types of DNA damage that are caused by a small molecule test agent. This includes single and double stranded breaks, alkali labile sites, oxidative base damage, and DNA cross-linking.
The Comet assay can detect specific DNA damage and repair, and thus can explore mechanism and mode of action to further investigate the effects of a compound.
At Inotiv, we offer Comet assays in multiple formats including:
Pig-a assay is a GLP-validated technique for measuring mutations caused by genotoxic effects of novel drug treatments or chemicals.
Gene mutation assays, like the Pig-a assay, measure the induction of mutations at a specific gene location as opposed to measuring overall DNA damage. This provides an advantage for product development and regulatory decision making.
Clear advantages of the Pig-a Assay include:
The entire Pig-a assay can be performed at Inotiv, or samples can be sent for analysis that can be performed alone or in conjunction with other endpoints (Micronucleus Assay, Comet Assay, Metaphase Analysis, etc.)
In vivo endpoints may be integrated into general toxicology studies with repeat dosing. Endpoints can be evaluated by Flow Cytometry (when available) or manual scoring (microscopy).
Endpoints include: In Vivo Micronucleus, In Vivo Comet, Pig-a