The Journal of Experimental Medicine, Vol 96, 439-450,
Copyright, 1952, by The Rockefeller Institute for Medical Research New York
THE USE OF PHOSPHORUS 32 IN STUDIES ON PLASMODIUM GALLINACEUM
:
I. THE DEVELOPMENT OF A METHOD FOR THE QUANTITATIVE DETERMINATION OF PARASITE GROWTH AND DEVELOPMENT IN VITRO
Delphine H. Clarke M.D.1
1 From the Laboratories of the Division of Medicine and Public Health of The Rockefeller Foundation, New York
A quantitative method for following parasite growth in vitro is described. The method is based on the determination of the degree of incorporation of phosphorus into the nucleic acids, in particular desoxypentose nucleic acids, of the parasitized cell. Phosphorus incorporation is measured by utilizing the radioactive isotope, P32.
The degree of phosphorus incorporation into DNA was found to be closely correlated with estimates of parasite growth based on stained film examinations of intact cell preparations. The isotope was likewise found to be incorporated into the DNA of preparations in which the host cell had been disrupted by lysis and the extent of this incorporation also paralleled the impressions gained from smear examinations.
It is suggested that this method provides a sensitive and objective method of studying parasite growth.
Submitted on June 24, 1952