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Katherine Stitzel

Publications and source records attributed to Katherine Stitzel.

5 recordsLinked to original sources
PubMed2006

Ensuring quality of in vitro alternative test methods: Current practice.

In Vitro toxicology methods are being validated and adopted by regulatory agencies for use as alternatives to animal testing. Such methods may use ex vivo tissues or bioconstructs, some of which may be proprietary. Users of the data from these methods need to be reassured that the assays or assay components used in their studies provide consistent, good quality data over time, matching the standards achieved during the validation process. This paper presents an overview of approaches currently used by representatives of a manufacturer and a contract testing laboratory to ensure that the results from in vitro alternative methods are reproducible and of high quality over time. These approaches include full characterization of cells or tissues, sampling of each lot of manufactured bioconstructs for performance, and regular use of controls and benchmark chemicals to provide assurance of consistency of assay performance.

Animal Testing Alternatives↗
PubMed2005

Ensuring quality of in vitro alternative test methods: issues and answers.

Many in vitro and ex vivo methods have been developed or are under development to reduce or replace animal usage in toxicity tests. Consistent with the goal of obtaining scientifically sound test data for hazard and risk assessment of chemicals, changes are being made in current policies and procedures to facilitate the acceptance of data developed using these methods. National and international organizations are developing policies and standards for scientific practice to assure quality in implementation of in vitro methods. Consensus is developing in the scientific community for the quality control measures needed for in vitro methods; including appropriate controls, data reporting elements, and benchmarks to be identified in test guidelines so that the potential risks of chemicals can be reviewed and reliably assessed. Additional guidance to the OECD's Good Laboratory Practice principles [Organization for Economic Cooperation and Development (. Advisory Document of the Working Group on Good Laboratory Practice: The Application of the Principles of GLP to in vitro Studies. OECD Series on Principles of Good Laboratory Practice and Compliance Monitoring Number 14 (ENV/JM/MONO(2004)26). Paris, France] will help to ensure that in vitro tests used for regulatory purposes are reproducible, credible, and acceptable. Generic test guidelines incorporating performance standards are being written to allow acceptance of proprietary test methods by regulatory agencies and to provide assurance that any in vitro system performs over time in a manner that is consistent with the test system as it was originally validated.

Animal Testing Alternatives↗
PubMed2002

Alternative methods for the median lethal dose (LD(50)) test: the up-and-down procedure for acute oral toxicity.

The authors have developed an improved version of the up-and-down procedure (UDP) as one of the replacements for the traditional acute oral toxicity test formerly used by the Organisation for Economic Co-operation and Development member nations to characterize industrial chemicals, pesticides, and their mixtures. This method improves the performance of acute testing for applications that use the median lethal dose (classic LD50) test while achieving significant reductions in animal use. It uses sequential dosing, together with sophisticated computer-assisted computational methods during the execution and calculation phases of the test. Staircase design, a form of sequential test design, can be applied to acute toxicity testing with its binary experimental endpoints (yes/no outcomes). The improved UDP provides a point estimate of the LD50 and approximate confidence intervals in addition to observed toxic signs for the substance tested. It does not provide information about the dose-response curve. Computer simulation was used to test performance of the UDP without the need for additional laboratory validation.

Animal Testing Alternatives↗