Single-Cell Mutation Monitoring Systems: Methodologies and Applications

There is general agreement that increased environmental pollution poses a potential health hazard to humans and that effective control of such genetic injury requires monitoring the exposed individuals for genetic damage and identifying chemicals that may cause mutation or cancer. Tests available for identifying mutagens or carcinogens range from relatively simple, rapid assays in prokaryotes and test systems utilizing mammalian cells in tissue culture to highly elaborate tests in intact animals. No single test can provide data for an unequivocal assessment of the mutagenicity of a given chemical and the risk it might pose to human health. A tier approach, therefore, was suggested for mutagenicity testing in which the suspected agents would be initially evaluated with simple, inexpensive tests that would give qualitative results. Chemicals found to be positive in the first-tier testing would then be evaluated with more complex tests, including those based on mammalian cells in culture. Testing in the final tier requires whole-animal studies, and is expensive and time-consum­ ing, and even the results from these studies need to be extrapolated for human risk assessment. The mutation systems based on whole animals require scoring large num­ bers of animals, and therefore are not practical for the routine testing of muta­ gens. As an alternative to monitoring the pedigree, cells from exposed individ­ uals may be considered for screening for point mutations through the use of an appropriate marker protein.

Table of Contents:
1. Somatic-Cell Mutation Monitoring System Based on Human Hemoglobin Mutants.- 1. Introduction.- 2. The Hemoglobin Mutants.- 3. Hemoglobin in Mutation Research: Gametal Mutation Rates.- 4. A System for Detecting Somatic Mutations of Hemoglobin.- 5. Methodological Aspects: Monospecific Anti-Mutant-Hemoglobin Antibodies.- 6. Methodological Aspects: Monoclonal Anti-Globin-Chain Antibodies.- References.- 2. Use of Fluorescence-Activated Cell Sorter for Screening Mutant Cells.- 1. Introduction.- 2. Immunologic Identification and Flow Detection of Erythrocytes Containing Amino Acid-Substituted Hemoglobin.- 3. Future of the Hemoglobin-Based Assay.- 4. Detection of Erythrocytes with Mutationally Altered Glycophorin A.- 5. Summary and Conclusions.- References.- 3. Development of a Plaque Assay for the Detection of Red Blood Cells Carrying Abnormal or Mutant Hemoglobins.- 1. Introduction.- 2. Principle of the Method.- 3. Reagents.- 4. Equipment.- 5. Procedure for the RBC-Antibody Plaque Assay.- 6. RBC-Protein A Plaque Assay.- 7. Conclusions.- References.- 4. Direct Assay by Autoradiography for 6-Thioguanine-Resistant Lymphocytes in Human Peripheral Blood.- 1. Introduction.- 2. Autoradiographic TGr T-PBL Assay Method.- 3. Sample Results.- 4. Statistical Analysis Methods.- 5. Discussion.- References.- 5. Application of Antibodies to 5-Bromodeoxyuridine for the Detection of Cells of Rare Genotype.- 1. Introduction.- 2. Materials and Methods.- 3. Results.- 4. Discussion.- 5. Summary.- References.- 6. Cytogenetic Abnormalities as an Indicator of Mutagenic Exposure.- 1. Introduction.- 2. Lymphocyte Assay Methodology.- 3. Chromosome Aberration Analysis Following Radiation or Chemical Exposure.- 4. The Analysis of Bone Marrow Samples.- 5. The Plausibility of Estimating Genetic or Carcinogenic Risk from Aberration Frequencies in Lymphocytes.- 6. Concluding Remarks.- References.- 7. Sister Chromatid Exchange Analysis in Lymphocytes.- 1. Introduction.- 2. Methodology.- 3. Selected Applications.- Appendix A. A Procedure for Growing and Preparing Human Lymphocytes for SCE Analysis.- Appendix B. A Procedure for Growing and Preparing Rat Lymphocytes for SCE Analysis.- References.- 8. Unscheduled DNA Synthesis as an Indication of Genotoxic Exposure.- 1. Introduction.- 2. Four Laboratory Approaches to Measuring Unscheduled DNA Synthesis.- 3. Methods.- 4. Reagents, Solutions, Stains, and Media.- 5. Equipment and Supplies.- References.- 9. The Micronucleus Test as an Indicator of Mutagenic Exposure.- 1. Historical Background.- 2. Rationale of the Test System.- 3. Technical Procedure.- 4. Results and Comparative Studies.- 5. Related Assay Systems.- 6. Advantages.- 7. Limitations.- 8. Application of the Micronucelus Test.- References.- 10. The Identification of Somatic Mutations in Immunoglobulin Expression and Structure.- 1. Introduction.- 2. Immunoglobulin Protein and Gene Structure.- 3. Methods for the Isolation of Mutants.- 4. Frequency and Phenotypes of Mutants.- 5. Discussion.- References.- 11. Detection of Chemically Induced Y-Chromosomal Nondisjunction in Human Spermatozoa.- 1. Introduction.- 2. Background.- 3. Agents That Increase YFF Bodies in Human Sperm.- 4. Discussion.- References.