CHAPTER 7 



THE FUTURE OUTLOOK 

 IN CYTOCHEMISTRY 



Of the many fields of cytology, cytochemistry has probably 

 been that which has grown most rapidly and been the scene of 

 the most intense activity in the past ten years. The next ten or 

 twenty years must inevitably see the consolidation of this field, 

 the refinement of many methods, and the invention of many new 

 methods. These activities seem likely to fall into three groups: 



1. The study of qualitative methods. 



2. The study of quantitative methods. 



3. The application of cytochemistry to the study of the fundamental 

 problems of cell biology. 



Under the first of these headings we must envisage the exten- 

 sion of studies to other regions of the spectrum, including the far 

 ultraviolet and the infrared, the development of new microscopic 

 instruments, particularly reflecting microscopes and perhaps also 

 the television microscope now being studied by A. K. Parpart. 

 The refinement of electron-microscope methods is much to be 

 hoped for. Methods involving the use of radioactive isotopes 

 may become prominent. The investigation of fluorescence meth- 

 ods and the use of specific quenching agents can be anticipated. 

 Great prominence will probably be given to methods for the 

 localization of enzymes and the study of substrate specificity as a 

 means of revealing the diversity of enzymes in cells. And the 

 method recently published by Coons and his colleagues, of using 

 tagged antibodies, if sufficiently sensitive may be of the greatest 

 value in studying a wide variety of proteins. 



In the study of quantitative methods probably the main tasks 

 are the defining of the limits of accuracy which can be obtained, 

 from both the chemical and the physical viewpoints. The de- 

 velopment of more sensitive photocells, for example, is likely to 

 be valuable, provided that the extent to which cytochemical re- 



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