HGPRT test

Muller W. 1987. Chloroform Detection of gene mutations in somatic cells in culture. HGPRT-test with V79 cells. Frankfurt, Germany Pharma Research Toxicology and Pathology, Hoechst Aktiengesellschaft. 

Not genotoxic (Ames and HGPRT tests, and in tests for detection of chromosomal aberrations (cytogenetics in vitro in V79 cells and in vivo in Chinese hamsters)... 

HG-OES hydride generation optical emission spectrometry (see HG-AES) HGPRT-test hypoxanthine-guanine-phos-pho-ribosyl-transferase test, a mutagenicity test with mammalian cells HHPN hydraulic high pressure nebulizer HIV human immunodeficiency virus HMDE hanging mercury drop electrode... 

It is noteworthy that antitumor active complexes (% T/C < 50), are also the two most mutagenic species as determined by the Ames and CHO/HGPRT test systems (27). The complexes are similar in that (a) through aquation the [Pt(NH3)Cl3] Ion can become a neutral molecule, cts-[Pt(NH3)(H20)Cl2] , and (b) both possess cis-reactive groups. Two Important criteria for antitumor activity to be exhibited are that complexes should be neutral and possess ois-reactlve groups. 

Lee CG, Webber TD. 1985. The induction of gene mutations in the mouse lymphoma L5178Y/K+/ assay and the Chinese hamster V79/HGPRT assay. In Ashby J, de Serres FJ, et al, eds. Progress in mutation research. Vol. 5. Evaluation of short-term tests for carcinogens. Amsterdam, The Netherlands Elsevier Science Publishers, 547-554. 

The preferred expression time for Hgprt mutants is 6-8 days, although care needs to be taken when testing chemicals well into the toxic range, where the expression time needs to be extended to allow recovery. 

Procedure for the Chinese Hamster V79/Hgprt Assay. The assay usually comprises three test concentrations, each in duplicate, and four vehicle control replicates. Suitable positive controls are ethylmethane sulphonate (—S9) and dimethyl benzanthracene (+S9). V79 cells with a low nominal passage number should be used from frozen stocks to help minimize genetic drift. The procedure described includes a reseeding step for mutation expression. 

Chinese Hamster CHO/Hgprt System. Chinese hamster ovary (CHO) cells have 21 or 22 chromosomes with one intact X chromosome and a large acrocentric marker chromosome (Natarajan and Obe, 1982). The use of these cells in mammalian mutation experiments was first reported by Hsie et al. (1975), and was refined into a quantitative assay for mutagenicity testing by O Neill. The performance of this system has been reviewed by the USA EPA Gene-Tox Program. The experimental procedure for this assay is similar to the V79/Hgprt system already described, and for more detailed descriptions the reader is referred to Li et al. (1987). 

Fox, M. Delow, G.F. (1985) Tests for mutagenic activity at the HGPRT locus in Chinese hamster V79 cells in culture. In Ashby, J., de Serres, F.J., Draper, M., Ishidate, M., Jr, Margolin, B.H., Matter, B.E. Shelby, M.D., eds, Progress in Mutation Research, Volume 5, Evaluation of Short-Term Tests for Carcinogens. Report of the International Programme on Chemical Safety s Collaborative Study on in vitro assays, Amsterdam, Elsevier Science, pp. 517-523... 

Fox, M. Delow. GF. (1985) Tests for mutagenic activity at the HGPRT locus in Chinese hamster V79 cells in culture. Prog. Mutat. Res., 5, 517-523... 

One system uses mouse lymphoma cells and detects mutations that cause deficiency of thymidine kinase (TK). Another uses Chinese hamster cells and detects mutations in the gene that produces hypoxanthine-guanine phosphoribosyl transferase (HGPRT). Both tests cure efficient, are widely applied, and can be completed in a few weeks. Although not as simple, rapid, and efficient as the Salmonella tests, they have the advantage of being done in a eukaryote. Mammalian-cell cultures cure also used to test for chromosomal mutation. 

For the short-term tests, we recommend a two-tier system. Tier I consists of a microbial gene-mutation test (Salmonella/microsome test), a mammalian cell-culture gene-mutation test (HGPRT or IK), and a mammalian cell-culture chromosomal-breakage test. All these cure to be done both with and without metabolic activation. If the... 

Prenatal and postnatal development none Genetic toxicology0 Ames test, human lymphocyte chromosomal aberration assay, CHO/HGPRT gene mutation assay, mouse micronucleus assay Carcinogenicity none... 

Prenatal and postnatal development rats Genetic toxicology Ames test, chromosomal aberrations in mammalian cells, micronuclei in mice, gene mutation at the HGPRT locus Carcinogenicity none... 

Gene mutation tests in a eukaryotic system in vitro, e.g. the Hypoxanthine - guanine - phosphoribosyl - transferase (HGPRT) gene mutation tests in hamster cells. 

In in vitro (bacterial reverse mutation, CHO/ HGPRT forward mutation, and rat lymphocyte chromosomal aberration assays) and in vivo (mouse bone marrow micronucleus assay) tests, fexofenadine hydrochloride revealed no evidence of mutagenicity. 

O Neill JP and Hsie AW (1979) The CHO/HGPRT mutation assay experimental procedure. In Hsie AW, O Neill JP, and McElhenny VK (eds.) Mammalian Cell Mutagenesis The Maturation of Test Systems, Banbury Report No. 2, pp. 55-70, 311-318, 407-420. Cold Spring Harbor, NY Cold Spring Harbor Press. 

Cytogenetic examination of bone marrow cells showed no increase in aberrations in maternal and neonatal rats following maternal oral exposure to a DeBDE and NoBDE mixture. In vitro assays found that DeBDE did not induce gene mutations in several bacterial tests (Ames assays) or in mammalian cells. DeBDE also did not induce chromosomal aberrations in Chinese hamster ovary cells. However, exposure to the congeners 2,2, 4,4 -tetra-BDE, 3,4-diBDE, and 2-monoBDE caused increased recombinogenic activity at the HGPRT locus in several cell lines. 

Quercetin, a flavonoid component of St. John s wort and several other medicinal plants, has been implicated as a mutagen. However, St. John s Wort aqueous ethanolic extract showed no mutagenic effects in mammalian cells. Tests used included the HGPRT (hypoxanthine guanidine phosphoribosyl transferase) test, the UDS (unscheduled DNA synthesis) test, the cell transformation test uring Syrian hamster embryo cells, the mouse fur spot test, and the chromosome aberration test using Chinese hamster bone marrow cells (Okpanyi et al., 1990). 

CR is stated not to be genotoxic in a Salmonella bacterial mutagenicity test, a CHO forward gene mutation test (HGPRT locus), mouse lymphoma cell assay (L5178Y/tk+/tk ), and a micronucleus test (Colgrave et al, 1983). 

DNT under anaerobic conditions produced 2-amino-4-nitrotoluene and 4-amino-2-nitrotoluene as well as azoxy compounds. Subsequently, the same team reported that technical grade 2,4-DNT as well as pure 2,4-DNT, 3,4-DNT and 2,6-DNT (at concentrations up to 2 mM) were nonmutagenic using standard conditions in the CHO-HPRT assay [42], Both 2,4-DNT and 2,6-DNT isomers gave negative results in the HGPRT-V79 assay when tested in absence of metabolic activation [43],... 

RDX was shown to be inactive in the UDS in WI-38 human fibroblasts, with and without S9 metabolic activation [47], Reported test concentrations were in the range of 250 to 4000 pg ml-1, well over the aqueous solubility of the compound (approximately 70 pg ml-1) [48], Similarly, in the HGPRT-V79 assay with or without metabolic activation, both RDX and HMX were inefficient in inducing 6-thioguanine resistant cells. The test concentrations used were up to 40 pg ml1 for RDX and 10 pg ml-1 for HMX, close to the solubility limit of these compounds in water [2], Another confirmation of the lack of mutagenic activity of RDX was provided recently when the compound was found inactive in the mouse lymphoma forward mutation assay using the L5178Y cell line [49],... 

O Neill, J.P., Brimer, P.A., Machanoff, R., Hirsch, G.P., Hsie, A.W. 1977. A quantitative assay of mutation induction at the hypoxanthine-quanine phosphoribosyl transferase locus in Chinese hamster ovary cells (CHO/HGPRT System) Development and definition of the system. Mutat. Res. 45 91-101. Huberman, E. 1976. Cell-mediated mutagenicity of different genetic loci in mammalian cells by carcinogenic polycyclic hydrocarbons. In Screening Tests in Chemical Carcinogenesis, eds. R. Montesano, H. Bartsch,... 

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