18 CONTEXTS 



CHAPTEE XIX 



PAGE 



Bacterial Antigens axu Specificity ___________ 350 



Bacterial Antigens; Complexity; Living Attenuated Antigens; 

 Killed Suspensions as Antigens; Early Eesearch on Antigens; 

 Species Specificity vs. Immunological Specificity, 350; Limitation 

 of Serological Methods; Species Showing Antigenic Homogeneity; 

 Sjtecies Showing a Few Serological Types; Species Showing Anti- 

 genic Heterogeneity, 351; Lack of Standard Procedure, .".52; 

 P^rrors Due to Presence of Extraneous Material in Antigens; Early 

 Work on Antigenic Fractions; Subsequent Investigations; Prop- 

 erties of Tuberculin, 353; Specific Substances in Bacteria, 354; 

 Antigenic Comparisons of Acid-Fast Bacteria; Lipoids; Rehitive 

 Importance of Lipoids, Proteins and Carbohydrates, 355 ; Tuber- 

 eulo-Phosphatids and Fatty Acids; Immuno-Chemical Studies of 

 tlie Pneumococcus ; Properties of Type Specific Polysaccharides, 

 356; Difference Between Immune Serum From Horses and Rabbits; 

 Possible Explanation of Inhibition Phenomenon, 35S; The "C" 

 Species-Specific But Not Type-Specific Substance of Tillett and 

 Francis; Carbohydrate Fractions Adsorbed on Carbon Particles; 

 Synthetic Carbohydrate Haptens, 359; Friedlander 's Bacillus, 361; 

 Escherichia coli ; E. lypliosa, 3(>.'! ; Shigella dysenteriae; V. cholerae; 

 H. influenzae, 364; H. pertussis; Brucella abortus; Hemolytic 

 Streptococci, 365 ; Other Bacterial Specific Substances, 366. 



CHAPTER XX 



Recapitui.ation of Chapters on Specificity ________ 374 



Examples of Specificity in Nature ; Antigens ; Properties of Protein 

 Antigens, 374; Species-Specificity and Type-Specificity; Differences 

 Within a Species, 375; Hapten May Dominate a Serological Reac- 

 tion; Suppression Phenomenon of I^andsteiner ; Arsanilic Acid Cou- 

 pled to Histidine and T^TOsine ])y Hooker and Boyd, 376; Haptens 

 Itosponsible for Cross-Reactions; Pneumococfus Type-Specific Poly- 

 saccharide Serum Globulin Antigen; Spatial Relationships and 

 Specificity Stereoisomers as Haptens, 377; Landsteiner 's Method 

 of Producing New Conjugated Antigens ; Suggested Explanation of 

 Drug Allergy; Mosaic Structure of Antigens, 378. 



CHAPTER XXI 



The Importance of Antibodies in Diagnosis ________379 



Discovery of Role of Agglutinins in Diagnosis — the Widal Test; 

 Scope of Subsequent Investigations; Antigens Used in the Widal, 

 379; Two Techniques Employed, 380; Incubation, Observation and 

 Interpretation of Results; Microscopic Method, 381; Controls; 

 Variation in Time of Appearance of Agglutinins, 382; Agglutinins 

 in Carriers; Normal Agglutinins and Diagnostic Titers; Flagellar, 

 Somatic and Labile Agglutinins, 383 ; Variations in Agglutination 



