Helix3 News

Friday September 30, 2011

Helix3 Now Offers DNA Reactivity Dose Response Curve Studies to Provide Supplemental Mechanistic Data

In response to regulatory requests for more data on the DNA reactivity of test compounds, metabolites, degradation products, and impurities, Helix3 has developed and now conducts DNA reactivity dose response curve studies exposing human nuclear DNA to up to 15 dose concentrations of a test compound. Without the confounding effects of cytotoxicity, repair, cell line differences, or cell division, this protocol provides a better alternative to the in vitro comet assay for assessing the dose response curve for the induction of DNA strand breaks, alkylation, DNA adducts, DNA-DNA and DNA-protein crosslinks across a wide range of dose concentrations.

Wednesday October 27, 2010

Helix3 Presents Regulatory Safety Testing with the In Vivo Comet Assay: Recommendations for Data Interpretation

To advance a better understanding of the in vivo comet assay and to demonstrate how it can be used effectively in safety testing, the results and interpretation of several studies evaluating pharmaceuticals are presented. Topics covered include details for assessing cytotoxicity, the determination of a positive genotoxic response, and recommendations for defending a negative response.

Monday December 6, 2009

Helix3 Publishes Combining the in vivo comet and micronucleus assays: a practical approach to genotoxicity testing and data interpretation to Address New ICH S2(R1)Guidelines

To address the recent S2(R1) modifications to the ICH Guidelines, Marie Vasquez published the most innovative protocol for combining the in vivo comet and micronucleus assays in Mutagenesis today. Using real study data, this publication provides for the first time and in explicit detail recommendations for study design, addressing cytotoxicity, and data interpretation in the comet assay. The complete article including supplemental figures is available free online at Mutagenesis.

Friday October 30, 2009

Helix3 Develops and Presents the Acellular Comet Assay as a Supplement Testing Strategies Designed to Reduce In Vivo Requirements

Helix3 has developed an acellular comet assay protocol In response to the concern that cytotoxic doses in the in vitro standard battery of tests lead to "false positive" results requiring unnecessary animal testing. Unaffected by cytotoxicity, cell division, repair, and/or cell type, the acellular comet assay provides a quick and easy means for determining whether a compound directly interacts with DNA and may provide better concordance to the comet assay in target organs.

The acellular comet assay combined with In vitro comet in live cells (either dividing or non-dividing) may also provide valuable mechanistic data that could otherwise go undetected for many test compounds. In doing so, this testing strategy could minimize the need for in vivo studies and/or provide opportunities for optimizing regulated study designs.

January 2009

Guenter Speit, Andreas Hartmann, and Marie Vasquez Publish The comet assay as an indicator test for germ cell genotoxicity in Mutation Research

Helix3 historical control data for several sex-specific tissues (e.g. mammery and prostate glands), portions of the endocrine system (e.g. pituitary and hypothalamus glands) as well as data from germ cells were published to demonstrate how the comet assay may be utilized for detecting genotoxicity in cells or tissues that may be directly or indirectly affected by endocrine disruption which can lead to sex-specific cancers and other health affects.