8o4 THE FUNCTIONAL ROLE OF AGGLUTININS 



motility followed by the Pfeiffer phenomenon. Salimbeni attributed the apparent 

 inagglutinability of the organisms in the body to lack of access of air which he demon- 

 strated in some way influenced them or their medium. 



A considerable number of investigators have contended, however, that intra 

 vitam agglutination is an important mechanism in immunity. Gruber,' in reporting 

 his studies on the specificity and practical application of the phenomenon of agglutina- 

 tion, expressed the opinion that agglutinins were quite essential properties of an im- 

 mune serum. He believed that agglutination was due to an increased viscidity of bac- 

 terial bodies which caused them to adhere to one another, Gruber advanced the idea 

 also that this increased viscidity aided in the englobement of the bacteria by the 

 phagocytes and would probably account for the accumulation of bacteria in the or- 

 gans when injected into the circulation. It was thought that the agglutinins in modi- 

 fying the bacterial membranes permit the penetration of the bodies of the bacteria 

 by the alexins which alone bring about the final destruction of the micro-organisms 

 which are then phagocyted. 



CLINICAL OBSERVATIONS ON THE RELATION OF AGGLUTININS TO PROGNOSIS 

 AND RECOVERY FROM INFECTION 



The first clinical observations on the activity of agglutinins in vivo were made by 

 Sawtschenko and Melkich.^ In an extensive investigation of recurrent fever they 

 made a careful study of the mechanism of immunity to Spirocheta obermeieri, both in 

 patients and experimental animals, and compared the action of immune serum in 

 vitro and in vivo. When the organisms were injected intraperitoneally into actively or 

 passively immunized guinea pigs and the exudate examined after ten to fifteen min- 

 utes many of the spirochetes were non-motile, and after forty minutes it was impossi- 

 ble to find motile organisms. Both fresh and stained preparations showed well- 

 marked agglutination and phagocytosis. 



In recurrent fever in man the agglutinative property is found in the serum or 

 plasma of the patients during apyrexia and especially during convalescence. Metch- 

 nikoff^ established the fact that the critical fall of temperature and disappearance of 

 the organisms from the blood always coincides with a well-marked phagocytosis in 

 the spleen. An important contributory factor to the phagocytic crisis, as shown by 

 Sawtschenko and Melkich, was the action of the agglutinins, which at this stage of the 

 disease could be easily demonstrated both in vitro and in vivo. The spirochetes could 

 be seen united into small clumps in both fresh and stained preparations made immedi- 

 ately after the blood was drawn. It was suggested that agglutination in the plasma 

 was incomplete because of the rapid movement of the blood. The accumulation of the 

 organisms in the spleen where phagocytosis was most marked was evidently due to 

 filtration of the clumps by this organ and their englobement en masse by phagocytic 

 cells. 



Many observers have attached great importance to agglutinins not only in the 

 diagnosis but also in the prognosis of such diseases as typhoid and Malta fever. After 



' Gruber, M.: Wien. kiln. Wchnschr., 43, 206. 1896. 



2 Sawtschenko, I., and Melkich, A. A.: Ann. de I'Inst. Pasteur, 15, 497. 1901. 



3 Metchnikofif, E.: Virchow's Arch.f. path. Anal., log, 176. 1887. 



