SERUM THERAPY 589 



peutic properties which depend upon phagocytosis and not upon any 

 bactericidal or antitoxic properties. 



The serum of a satisfactorily vaccinated rabbit is very potent ; 2 or 

 4 drops of the serum of such a rabbit is sufficient to immunize a mouse 

 (Foa and Carbone) : Neufeld and Handel's serum protects mice against 

 100,000 fatal doses (vide ante). 



G. and F. Klemperer arrested a pneumococcal septicaemia in a rabbit 

 infected 24 hours previously by inoculating it with 8 c.c. of the serum of a 

 vaccinated rabbit. Tizzoni and Panichi prepared a serum which exhibited 

 therapeutic properties for the rabbit when given intra-venously in doses 

 of 0'25 per 1000 of the weight of the animal. 



The same observers have shown that at the moment of the crisis in human 

 lobar pneumonia the serum of the patient which is toxic during the febrile 

 period acquires immunizing and therapeutic properties. 



Therapeutic applications. Many observers relying upon the satisfactory 

 results obtained in laboratory experiments have treated pneumococcal 

 infections in the human subject with immunized rabbit serum and with the 

 serum of patients who have survived the crisis. The results so far obtained 

 though satisfactory are not sufficiently striking to. warrant the method being 

 generally adopted. 



Klemperer has shown that the inoculation of antipneumococcal serum into the 

 healthy human subject is unaccompanied by any untoward symptoms. In cases 

 of pneumonia he inoculated immunized rabbit serum in doses of 6 c.c. sub-cutaneously 

 with favourable results. Foa and Carbone provoke the crisis on the fourth day by 

 giving two consecutive inoculations of 5 c.c. of the immunized rabbit serum. Foa 

 and Scabia and also Janson also noticed a rapid improvement in several cases of 

 pneumonia following the injection of 5-25 c.c. of the serum of a vaccinated rabbit. 

 Neufeld and Handel recommend the inoculation of large doses of their serum : 

 Romer favours the use of a polyvalent serum : Pane uses immunized ass serum. 



Audeoud inoculated cases of pneumonia with 24 c.c. of blood taken from patients 

 who had passed the crisis, and in two of them he obtained a marked improvement 

 and a fall of temperature in 15 hours after the inoculation. Bouchard, Roger, 

 Charrin, Maraglia'ho have obtained favourable results under similar circumstances. 



For the purposes of these experiments the blood can be collected from cases of 

 pneumonia in the early stages of convalescence without causing any inconvenience, 

 by adopting the technique described on p. 193. 



6. Agglutination. 



In pneumococcal infections the serum of man and the lower animals acquires 

 the property of agglutinating the pneumococcus. The agglutinating power 

 is never other than feeble : it cannot be demonstrated by the Grunbaum- 

 Widal method but only in undiluted serum cultures (Bezan9on and Griffon). 



The serum must be collected aseptically and should not be stained with 

 haemoglobin. It is sown with a trace of culture on normal rabbit-serum and 

 incubated at 37 C. for 15 or 16 hours. 



The agglutination may be visible to the naked eye or only evident on 

 microscopical examination. It is very distinct in a drop of culture spread 

 out, dried, and stained (the " Medusa head " appearance of Bezancon and 

 Griffon). The pneumococcus is never agglutinated by normal human, rabbit 

 or dog serum. 



In human pneumococcal infections (pneumonia, broncho-pneumonia, sore 

 throat, etc.) the agglutination reaction is always positive, but diminishes 

 during convalescence and soon vanishes altogether. 



Agglutination is not obtained with all strains of the pneumococcus ; it is 

 in a way an individual and not a specific property. Very often agglutination 



