An "International Workshop on Genomic Instability: Basic and Applied Aspects" was jointly organized by Environmental Mutagen Society of India (EMSI) and School of Bio-sciences and Technology, Vellore Institute of Technology under the guidance of Prof. Wilner Martinez-Lopez (Biological Research Institute “Cemente Estable”-Uruguay, IIBCE) and Prof. Radha Saraswathy (School of Bio-sciences and Technology, VIT).
Toxicology and Radiation Biology
- Environmental Mutagenesis
- Mutation Research
Based on the Metafer slide scanning platform, MetaSystems offers an unrivaled portfolio of imaging automation applications for toxicology, radiation biodosimetry, and mutation research. Metafer is the perfect tool for dose-response analyses – extremely fast to generate instant results in biodosimetry, fully compliant to GLP regulations applied to preclinical genotoxicity studies, sensitive to detect even low dose effects in environmental mutagenicity tests, and highly flexible to be adapted to any study in mutation research labs.
Counting dicentric chromosomes and other chromosomal aberrations is generally referred to as the 'Gold Standard' for radiation biodosimetry. Though the assay has been proven to deliver best dose estimates in radiation accidents and in toxicology studies, it is usually time consuming and labor intensive. Metafer with its dedicated tools and the automated dicentrics scoring software frees the researcher from all tedious and error prone tasks on the way. Additionally it offers the complete working environment to generate fully documented and reliable results in shortest time – of course compliant to GLP regulations and to the OECD guideline #473 (In-Vitro Mammalian Chromosome Aberration Test).
The cytokinesis-block micronucleus (in-vitro MN) test and the mammalian erythrocyte micronucleus (in-vivo MN) test are both used as tools for fast and precise quantification of DNA damage. Metafer offers complete automation for both tests – reliable, fast, and fully documented. Users of the in-vitro MN test receive their results in a few minutes, and each detected bi-nucleate is displayed as a gallery image, together with its micronucleus count. The amounts of mono-, bi-, and multi-nucleates are recorded and can be used to calculate the CBPI.
Check the new pan-centromeric probe of MetaSystems Probes.For the in-vivo MN test, Metafer automatically assigns each cell to its respective sub-population (PCE or NCE). The assignment is done based on the staining of the cell, and it has the robustness to automatically adapt to various staining conditions. Micronuclei are counted in each population, and displayed separately as a histogram. Both tests are GLP compliant and follow the directive of the respective OECD guidelines (#487 for the in-vitro MN test and #474 for the in-vivo MN test). Results can either be summarized in comprehensive and customizable Neon reports, or directly be exported to any external statistics software package.
The Comet assay, also known as single cell gel electrophoresis (SCGE) assay, detects DNA damage and repair in individual cells. One major advantage of the Comet assay is the direct assessment of damage on a cell-by-cell basis. The sensitivity of the assay, however, makes it vulnerable to various factors which can affect reproducibility of results.
Users of MetaSystems devices are able to fully standardize the analysis part of the Comet assay. MetaSystems offers an interactive workstation and an automated slide scanning system based on the Metafer platform. Both systems use sophisticated algorithms to obtain head and tail intensities, lengths, and background conditions, and they automatically calculate tail moments and Olive tail moments. The automated system performs the analysis completely unattended, and it is capable to distinguish between ‘normal’ cells and hedgehog comets. Each cell is documented as an image and can also be relocated on the microscope. Data are displayed in handy reports, on-screen graphs, and values assigned to the gallery images.
Phosphorylated H2AX (also known as γ-H2AX) is a marker for DNA double strand breaks. Fluorescently labeled γ-H2AX protein clusters can be microscopically detected, and thus, can be used as a very direct marker for DNA damage and repair. Metafer finds target cell nuclei, acquires signals from multiple focus planes and in up to 12 color channels, and automatically analyzes the signals. Co-localization of signals from different channels, analysis of fused signals, and intensity measurements are possible.
The Ames II / Ames MPF test (based on the method of Xenometrix AG, Basel, Switzerland) is widely used to assess the mutagenic and toxic potential of compounds. The test uses bacteria carrying DNA mutations in genes involved in the synthesis of the amino acid histidine. The Ames II and Ames MPF assays are modernized versions of the original Ames test, using liquid culture instead of agar plates. The assays are done on 384-well micro titer plates and have a colorimetric read-out, which can be automatically analyzed by Metafer. Each single well is interpreted either positive or negative, giving the user the opportunity to change automatic scores in case of ambiguous results. Printed results contain color images of each well resulting in a complete overview of the 384 well micro plate.