338 TEMPERATURE COEFFICIENT OF PHAGOCYTOSIS 



This general conception is obviously applicable to the experiments 

 of Madsen and Watabiki, where three separate reactions can be 

 clearly distinguished by mere inspection of their curves in Fig. 1. 

 These reactions are: (1) a preparatory reaction represented by the 

 latent period, during which it may be supposed that the leucocytes, 

 originally inactive, are rendered active; (2) a lethal reaction which 

 injures the leucocytes so that they are again inactive; and (3) the 

 phagocytic reaction proper. 



The relations between these three reactions may be diagrammed 

 as follows :^ 



Ci 



i 



CB 



Here C stands for white blood corpuscles and CB for corpuscles 

 containing bacteria. Now the rate of the phagocytic reaction (3) 

 evidently depends upon the concentration of C active I ^"^^ the accuracy 

 of our analysis depends upon the assumption that this concentration 

 is the same at different temperatures during the periods selected 

 as corresponding periods in the reactions. The . concentration 

 of Cactive depends in turn upon the relative rates of the prepara- 

 tory and lethal reactions. Could we know the rates and dynamics 

 of both these reactions as well as their temperature coefficients we 

 could calculate the variation of Cactive with time by Osterhout's 

 equations (6) for the calculation of the concentration of M in the 

 series A-^M-^B. In this way corresponding stages could be ac- 



^ In this diagram no assumption is implied as to whether the effect of reactions 

 (1) and (2) in "activating" and "inactivating" the cells is due to an action upon 

 the cells themselves or upon the medium or bacteria. It merely states the fact 

 that their phagocytic activity passes through a maximum during the experiment, 

 due to two reactions. 



