Flow cytometric gene mutation assay, made possible by immunomagnetic separation, achieves OECD regulatory status

Litron laboratories developed the Pig-a gene mutation assay as a means to simply and reliably evaluate the potential mutagenicity of compounds. Commercially available from Litron Laboratories under the name MutaFlow, this method utilizes the endogenous phosphatidylinositol glycan class A gene found in most mammalian species as a reporter of gene mutation. During early development, the assay was challenged by the rare event nature of this analysis and the time and effort required to interrogate a sufficient number of events in order to reliably calculate a mutation frequency in peripheral red blood cells. Following the addition of labeling of cells with superparamagnetic beads and the use of immunomagnetic columns to focus analysis on the cells of interest, the sample throughput and number of events scored was dramatically increased.

 

This critical improvement facilitated the continued development and commercialization of the assay into a successful line of kits and services. Subsequent to additional work by Litron and others, the validation of the assay was deemed sufficient to submit for regulatory approval in the form of Test Guideline development by the Organization of Economic Cooperation and Development (OECD). The formal “Test Guideline 470 Mammalian Erythrocyte Pig-a Gene Mutation Assay” was adopted in June of this year and serves to establish the assay as applicable for regulatory safety submissions.

 

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