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The Contrast in the Reactions to the Implantation of Cancer after 

 the Inoculation of Living and Mechanically Disintegrated 

 Cells. 



By M. Haalaxd, M.D., Imperial Cancer Eesearch Fund. 



(Communicated by Prof. J. Rose Bradford, Sec. E.S. Eeceived January 17, — 



Bead February 3, 1910.) 



The object of the present paper is to show the difference obtaining between 

 the employment of tlie living cell, cancerous and normal, as an agent to 

 induce active resistance to the implantation of cancer cells, and the employ- 

 ment for the same purpose of the protein obtained from these cells by 

 mechanically disintegrating them. As a means of devitalising the cells with 

 least disturbance of their chemical properties, the method adopted was that of 

 grinding them either in the Macl'adyen-Eowland apparatus at the tempera- 

 ture of liquid air, or in a mortar, cooled by embedding it^ in ice and salt. 

 Comparison of the results obtained by both methods showed that the latter 

 was the more efficacious. By interrupting the freezing, tlie material can be 

 kept of a pasty consistence specially favourable for crushing all the cells. 

 The completeness of the disintegration of the cells was ascertained by micro- 

 scopic examination, revealing the absence of intact nuclei, and, in the case of 

 the cancer tissue, also by inoculation of the material not yielding tumours. 

 Every precaution has been taken to employ mice as uniform in age, size, and 

 weight as possible, in order to make the estimations upon a soil of uniform 

 natural resistance. 



In order to analyse the results more closely in each experiment, the 

 animals were killed after the same interval of time, when the tumours 

 threatened to ulcerate, and all the tumours obtained were weighed. The 

 protocol of such an experiment is given, showing all the details of the experi- 

 ment, including : (1) The length of time elapsed between inoculation and 

 the date when mice were killed ; (2) number of tumour mice aKve up till 

 then ; (3) total number of mice alive ; (4) total weight of tumour obtained ; 

 and (5) average weight of mice. To obtain an estimate of the average 

 growth, two calculations have been made : the one indicates the average 

 weight of tumour obtained, calculated on all the animals of the series living 

 up till the time when they were killed (negative included) : (" average weight 

 of tumours pro mouse ") ; the other gives the average weight of each tumour,, 

 when only the positive mice are taken into account (" average weight of 

 tumours pro tumour "). It seemed inadvisable to use the figures obtained 



