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Why are the Killed S. typhi Vaccines Ineffective
Zbl. Bakt. Hyg., I. Abt. Orig. A 246, 184-190 (1980) Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
Why are the Killed S. typhi Vaccines Ineffective Griinde der Unwirksamkeit von Impfstoffen aus getoteten S. typhi CELLA BARBER with the technical assistance of Mrs. RINA HElBER With 5 Figures· Received August 18, 1979
Abstract The mosaic of proteins synthesized by S. typhi, S. enteritidis and E. coli, induced in immunized rabbits corresponding antibodies that precipitated almost indiscriminately numerous heterologous antigens. Antibodies induced against eventual specific antigens could not be identified unless the sera were absorbed with heterologous proteins. The comparative immunochemical analysis of the total and absorbed sera proved that the proteins from E. coli are mixed with proteins sharing Salmonella specificities while E. coli proteins are present in the mixtures of proteins isolated from S. enteritidis and S. typhi. The absorption of anti S. typhi sera with proteins from different E. coli serotypes, removed a large amount of antibodies, leaving free for reaction those induced against Salmonellae common proteins. The absorption of the anti S. typhi sera with proteins from S. enteritidis eliminated the totality of precipitating antibodies meaning that no specific antibody was induced in the sera of animals immunized with S. typhi proteins. In contrast, the S. enteritidis proteins induced antibodies against a specific S. enteritidis protein, in addition to numerous heterologous determinants ; the existence of the specific antibody was evident in all the absorbed sera, notwithstanding the eventual relationship with the heterologous absorbing proteins. Absorptions of the antisera to proteins from E. coli with proteins from either S. typhi or S. enteritidis removed the antibodies induced against the absorbing proteins leaving free for reactions antibodies for the specific E. coli proteins. As the behaviour in vivo of the human pathogen is quite different from that of E. coli or S. enteritidis, the absence of a specific antigen in the material synthesized by S. typhi grown on artificial media provides an explanation for the inefficacy of vaccinations with killed S. typhi.
Zusammenfassung Der Komplex der von S. typhi, S. enteritidis und E. coli synthetisierten Proteine induzierte bei immunisierten Kaninchen entsprechende Antikorper, die gegen zahlreiche heterologe Antigene eine fast unterschiedslose Prazipitation aufwiesfn.
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Gegen moglicherweise vorhandene spezifische Antigene induzicrte Antikorper liel~en sich erst identifizieren, wenn die Seren mit heterologen Proteinen absorbiert wurden. Mittels vergleichender immunchemischer Analyse der gesamten und der absorbierten Seren konnte nachgewiesen werden, dag die E. coli-Proteine mit Proteinen gemischt sind, die Spezifitaten mit Salmonella gemeinsam haben, wahrend in den aus S. enteritidis und S. typhi isoJierten Proteingemischen E. coli-Proteine vorhanden sind. Die Absorption von S. typhi-Antiseren mittels Proteinen verschiedener E. coli-Serotypen eJiminierte eine groge Zahl von Antikorpern, so dag lediglich die gegen gemeinsame Salmonella-Proteine indizierten Antikorper verblieben und reagieren konnten. Die Absorption der S. typhi-Antiseren mittels S. enteritidis-Proteinen eliminierte die Gesamtheit der prazipitierenden Antikorper, d.h. dag in den Seren von mit S. typhiProteinen immunisierten Tieren keine spezifischen Antikorper induziert wurden. 1m Gegensatz dazu induzierten die S. enteritidis-Proteine Antikorper gegen ein spezifisches S. enteritidis-Protein neben zahlreichen heterologen Determinanten. Das Vorhandensein der spezifischen Antikorper war in allen absorbierten Seren nachweisbar, ungeachtet einer eventuellen Verwandtschaft mit den heterologen absorbierenden Proteinen. Eine Absorption von S. typhi- oder S. enteritidis-Antiseren zu aus E. coli gewonnenen Proteinen eliminierte die gegen die absorbierenden Proteine induzierten Antikorper, so dag die Antikorper fur die spezifischen E. coli-Proteine frei bJieben und reagieren konnten. Da sich das Verhalten des menschenpathogenen Erregers in vivo stark von dem von E. coli oder S. enteritidis unterscheidet, bietet das Fehlen eines spezifischen Antigens in dem durch auf kunstlichen Nahrboden gezuchtete E. coli synthetisiertem Material eine Erklarung fur die fehlende Wirksamkeit von Schutzimpfungen mit abgetoteten S. typhi.
Introduction We have shown recently (7) that Enterobacteriaceae grown on artificial media synthesize a variety of proteins, the existence of which was proven with the help of sera prepared in rabbits, with proteins from: S. enteritidis, S. typhi, S. typhimurium, S. paratyphi C, E. coli 0 126 and Sh. sonnei. All the sera precipitated, in agar-gel, against numerous heterologous proteins by superimposed precipitation lines. Comparative immunochemical analysis of the antiproteinic sera and corresponding antibacterial sera proved that the bacteria induced antibodies against a reduced number of heterologous antigens; it was evident from the results that a competition among the numerous antigens of a species takes place when bacteria are used for immunizations. As a consequence, antiproteinic sera were used in the present work in order to determine eventual wider ranges of relationships among Enterobacterial species of which the main antigens are the proteins (4). Interferences with polysaccharide-carrier proteins in somatic conjugates of bacteria were also eliminated by the use of antiproteinic sera. Since these sera precipitate almost indiscriminately against heterologous proteins the initial sera had to be absorbed in order to determine the eventual specific and common induced antibodies. In this report we present results concerning: S. typhi, S. enteritidis and E. coli. It appears, from the immunochemical analysis, that the proteins isolated from these species are mixtures with specificities for both Salmonellae and E. coli. The proteins from E. coli contain free proteins with Salmonella specificities of which the corresponding induced antibodies are easily removed by absorption with Salmonella protein; specific antibodies for E. coli are abundant in the absorbed E. coli sera.
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The proteins from S. enteritidis are mixtures of proteins with E. coli specificities, proteins with common Salmonellae specificities and a specific protein for S. enteritidis which was identified in all the heterologous absorbed sera. In contrast, a specific protein for S. typhi could not be identified; the mixture of proteins isolated from S. typhi contains proteins with E. coli specificity and with common Salmonellae specificities only. Materials and Methods The sera to proteins from S. typhi 0 901 , S. enteritidis and E. coli 0126 are those used in our previous work (7). The proteins were prepared as usual (1): 5 gr. acetone-dried bacteria were suspended in 100 cc veronal buffer (pH 8.4) and maintained for 48 hours at 37°C with frequent stirring. After discarding the bacteria by centrifugation, the proteins present in the clear supernatant are precipitated with trichloracetic acid (final cone. 10%) For purification, the deposited proteins are suspended in distilled water and solubilized at pH 7-7.4 with dilute NaOH; the insoluble material is discarded and 2-3 more reprecipitations and solubilizations are performed, in order to eliminate eventual traces of somatic conjugates, before dialysis and lyophilisation of the proteins. Because of the well known differences in the immune responses of the rabbits, aIiquots of the same serum were used for absorptions with heterologous proteins and the absorbed sera were tested in comparison with the initial serum. The sera, necessarily diluted by absorptions were readjusted to the initial volume by dialysis against Carbowax. Agar-gel diffusion was used for the immunochemical analysis of the total and absorbed sera; the absorptions are laborious and 5-6 consecutive absorptions were necessary for the exhaustion of the sera of heterologous antibodies. Results and Discussion The immunochemical analysis of the sera prepared with proteins from: S. typhi, S. enteritidis and E. coli 0 126 and consecutively absorbed with the respective heterologous proteins showed some unexpected results. These could not be observed with antibacterial sera, in which due to strong competitions not all the antigens of a strain induce respective antibodies (2), nor could these results be perceived in unabsorbed sera in which numerous superimposed precipitation lines are given, against the total sera, by most of the tested heterologous proteins. The materials isolated from S. typhi, S. enteritidis and E. coli appear to be mixtures of proteins with Salmonella and E. coli specificities. The absorption of the serum to proteins from S. typhi 0 901 with the proteins from two E. coli strains (055 and 0126) removed different amounts of E. coli antibodies and left, in the absorbed sera, small quantities of antibodies induced against common proteins to S. enteritidis and the homologous S. typhi (Fig. 1). The absorption of the anti E. coli serum with proteins from S. typhi removed the antibodies induced against free proteins of S. typhi present in the mixture of E. coli proteins; the absorbed E. coli serum precipitated against the specific proteins of 3 different strains of E. coli: 055' 0 126, Om (Fig. 2). The serum to S. typhi proteins, which initially precipitated numerous heterologous proteins from Salmonellae, by numerous superimposed lines, did not react, after absorption with proteins from S. enteritidis, against the homologous antigen; very faint precipitation lines still reacting, in agar-gel, were directed against common determinants (Fig. 3).
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Fig. 1. Precipitations of proteins from S. typhi and S. enteritidis against the anti S. typhi serum absorbed with proteins from E. coli. I = serum to proteins from S. typhi 0 901 ; I a = the serum I absorbed with proteins from E. coli 0,,; I b = the serum I absorbed with protein from E. coli 0126 II = serum to proteins from S. enteritidis a = proteins from E. coli 0" b = proteins from E. coli 0 126 e = proteins from S. enteritidis t = proteins from S. typhi 0 901
Fig. 2. Absorptions of sera to E. coli 0 ,2 , and to S. typhi 0 901 proteins with respective heterologous proteins, removed the antibodies induced against the free proteins present in the mixtures of both species. I = serum to proteins from E. coli 126 Ia = serum to proteins from E. coli 126 absorbed with proteins from S. typhi II = serum to proteins from S. typhi IIa = serum to proteins from S. typhi absorbed with proteins from E. coli 0 55 a = proteins from S. typhi 0 901 ; b = proteins from E. coli 126 c = proteins from E. coli 0 50 ; d = proteins from E. coli 1l9
188
C.Barber
o
® G)
;0@Ji 0WI 0 0GG) Fig. 3. The absorption of sera to proteins from S. typhi with S. enteritidis proteins removed all the antibodies induced by the immunizations; traces of precipitating antibodies, still present in the absorbed sera, are directed against common determinants. I = serum to proteins from S. typhi 0 901 Ia = serum to proteins from S. typhi 0 901 absorbed with proteins from S. enteritidis a = proteins from S. enteritidis; b = proteins from S. typhi c = proteins from S. typhimurium; d = proteins from S. paratyphi B e = proteins from E. coli 0 55 ; f = proteins from S. kentucky g = proteins from S. choleraesusis
The antigens of S. gallinarum were found earlier (3, 5) to be only a part of S. enteritidis antigens; since protection in chickens are obtained only with living bacteria (6) we assumed that other antigens must be synthesized in the birds beside those obtained on artificial media. The fact that S. typhi shares all its determinants with S. enteritidis, when grown on artificial media, seems to us significant since "in vivo" these species behave differently. The proteins from S. enteritidis induced, during similar immunizations, antibodies against numerous determinants, in addition to a specific anti-So enteritidis antibody. Aliquots of the same serum absorbed with proteins from different species of Salmonellae removed corresponding heterologous antibodies but always the specific anti S. enteritidis antibody was present in the absorbed sera (Fig. 4). Sera of the rabbits were, again and again, absorbed with heterologous proteins, with repeated confirmations of the fact that S. enteritidis
Fig.S. Confirmation, with different absorbed sera, of the absence of a specific S. typhi antigen in contrast to the existence of the specific S. enteritidis induced antibody. I = serum to proteins from S. typhi 0 901 Ia = serum to proteins from S. typhi 0 901 absorbed with proteins from E. coli 126 II = serum to proteins from E. coli 0 126 III = serum to proteins from S. enteritidis absorbed with proteins from S. paratyphi B t = proteins from S. typhi 0 901 a = proteins from E. coli 126 s = proteins from S. choleraesuis e = proteins from S. enteritidis
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Fig. 4. The absorption of aliquots of the same S. enteritidis serum with heterologous proteins, while removing heterologous antibodies according to the relationship of the absorbing antigens, leaves in all the sera the specific antibody induced by S. enteritidis specific protein. I = serum to proteins from S. enteritidis Is = the serum absorbed with proteins from S. choleraesuis IPB = the serum absorbed with proteins from S. paratyphi B It = the serum absorbed with proteins from S. typhi 0 901 E = proteins from S. enteritidis S = proteins from S. choleraesuis t = proteins from S. typhi 0 901 PB = proteins from S. paratyphi B
Fig. 5 13
Zbl. Bakt., 1. Abt. Orig. A 246
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C. Barber
synthesizes a specific protein in contrast to S. typhi, in which there are only common Salmonellae proteins and proteins with E. coli specificities. The abundance of antibodies specific for E. coli was evident in all the total and absorbed anti-So typhi and S. enteritidis sera (Fig. 1,2,5). Among the actual analyzed species, S. typhi as a human pathogen has "in vivo" a behaviour that is quite different from that of either S. enteritidis or E. coli. Our results, proving that in the S. typhi grown on artificial media a specific antigen is not synthesized, provide an explanation for the ineffectiveness of mass-vaccinations with S. typhi. References 1. Barber, C.: Le Tampon-Veronal, moyen d'extraction des antigenes bacteriens. Arch. roum. de Path. expo 20 (1961) 541-543 2. Barber, C. and E.Eylan: Naturally occurring Competition between Homologous Polysaccharides and Proteins of Bacteria. ZbI. Bakt. Hyg., 1.Abt. Orig. A 222 (1972) 90-95 3. Barber, C. and KEylan: The Unfortunate Role of Precedent in Bacteriology. II. Unrelated Serological Specificities of the Polysaccharides from S. typhi and S. gallinarum Sharing Factors 9.12. ZbI. Bakt. Hyg., 1. Abt. Orig. A 236 (1976) 83-88 4. Barber, C. and E.Eylan: The Unfortunate Role of Precedent in Bacteriology. 1. The main Antigens of Salmonellae: the Proteins. ZbI. Bakt. Hyg., 1.Abt. Orig. A 234 (1976) 53-59 5. Barber, C. and KEylan: Salmonella gallinarum - Salmonella enteritidis Relationship in Rabbits. ZbI. Bakt. Hyg., 1.Abt. Orig. A 237 (1977) 201-206 6. Barber, C. and KEylan: Production of Precipitating Antibodies in Chickens Infected with Salmonella gallinarum. ZrI. Bakt. Hyg., 1. Abt. Orig. A 237 (1977) 207-212 7. Barber, C. and E.Eylan: The Numerous Common Antigens of Enterobacteriaceae. ZbI. Bakt. Hyg., 1. Abt. Orig. A 244 (1979) 251-259 Dr. Cella Barber, Dept. of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
Why are the Killed S. typhi Vaccines Ineffective Griinde der Unwirksamkeit von Impfstoffen aus getoteten S. typhi CELLA BARBER with the technical assistance of Mrs. RINA HElBER With 5 Figures· Received August 18, 1979
Abstract The mosaic of proteins synthesized by S. typhi, S. enteritidis and E. coli, induced in immunized rabbits corresponding antibodies that precipitated almost indiscriminately numerous heterologous antigens. Antibodies induced against eventual specific antigens could not be identified unless the sera were absorbed with heterologous proteins. The comparative immunochemical analysis of the total and absorbed sera proved that the proteins from E. coli are mixed with proteins sharing Salmonella specificities while E. coli proteins are present in the mixtures of proteins isolated from S. enteritidis and S. typhi. The absorption of anti S. typhi sera with proteins from different E. coli serotypes, removed a large amount of antibodies, leaving free for reaction those induced against Salmonellae common proteins. The absorption of the anti S. typhi sera with proteins from S. enteritidis eliminated the totality of precipitating antibodies meaning that no specific antibody was induced in the sera of animals immunized with S. typhi proteins. In contrast, the S. enteritidis proteins induced antibodies against a specific S. enteritidis protein, in addition to numerous heterologous determinants ; the existence of the specific antibody was evident in all the absorbed sera, notwithstanding the eventual relationship with the heterologous absorbing proteins. Absorptions of the antisera to proteins from E. coli with proteins from either S. typhi or S. enteritidis removed the antibodies induced against the absorbing proteins leaving free for reactions antibodies for the specific E. coli proteins. As the behaviour in vivo of the human pathogen is quite different from that of E. coli or S. enteritidis, the absence of a specific antigen in the material synthesized by S. typhi grown on artificial media provides an explanation for the inefficacy of vaccinations with killed S. typhi.
Zusammenfassung Der Komplex der von S. typhi, S. enteritidis und E. coli synthetisierten Proteine induzierte bei immunisierten Kaninchen entsprechende Antikorper, die gegen zahlreiche heterologe Antigene eine fast unterschiedslose Prazipitation aufwiesfn.
Why are the Killed S. typhi Vaccines Ineffective
185
Gegen moglicherweise vorhandene spezifische Antigene induzicrte Antikorper liel~en sich erst identifizieren, wenn die Seren mit heterologen Proteinen absorbiert wurden. Mittels vergleichender immunchemischer Analyse der gesamten und der absorbierten Seren konnte nachgewiesen werden, dag die E. coli-Proteine mit Proteinen gemischt sind, die Spezifitaten mit Salmonella gemeinsam haben, wahrend in den aus S. enteritidis und S. typhi isoJierten Proteingemischen E. coli-Proteine vorhanden sind. Die Absorption von S. typhi-Antiseren mittels Proteinen verschiedener E. coli-Serotypen eJiminierte eine groge Zahl von Antikorpern, so dag lediglich die gegen gemeinsame Salmonella-Proteine indizierten Antikorper verblieben und reagieren konnten. Die Absorption der S. typhi-Antiseren mittels S. enteritidis-Proteinen eliminierte die Gesamtheit der prazipitierenden Antikorper, d.h. dag in den Seren von mit S. typhiProteinen immunisierten Tieren keine spezifischen Antikorper induziert wurden. 1m Gegensatz dazu induzierten die S. enteritidis-Proteine Antikorper gegen ein spezifisches S. enteritidis-Protein neben zahlreichen heterologen Determinanten. Das Vorhandensein der spezifischen Antikorper war in allen absorbierten Seren nachweisbar, ungeachtet einer eventuellen Verwandtschaft mit den heterologen absorbierenden Proteinen. Eine Absorption von S. typhi- oder S. enteritidis-Antiseren zu aus E. coli gewonnenen Proteinen eliminierte die gegen die absorbierenden Proteine induzierten Antikorper, so dag die Antikorper fur die spezifischen E. coli-Proteine frei bJieben und reagieren konnten. Da sich das Verhalten des menschenpathogenen Erregers in vivo stark von dem von E. coli oder S. enteritidis unterscheidet, bietet das Fehlen eines spezifischen Antigens in dem durch auf kunstlichen Nahrboden gezuchtete E. coli synthetisiertem Material eine Erklarung fur die fehlende Wirksamkeit von Schutzimpfungen mit abgetoteten S. typhi.
Introduction We have shown recently (7) that Enterobacteriaceae grown on artificial media synthesize a variety of proteins, the existence of which was proven with the help of sera prepared in rabbits, with proteins from: S. enteritidis, S. typhi, S. typhimurium, S. paratyphi C, E. coli 0 126 and Sh. sonnei. All the sera precipitated, in agar-gel, against numerous heterologous proteins by superimposed precipitation lines. Comparative immunochemical analysis of the antiproteinic sera and corresponding antibacterial sera proved that the bacteria induced antibodies against a reduced number of heterologous antigens; it was evident from the results that a competition among the numerous antigens of a species takes place when bacteria are used for immunizations. As a consequence, antiproteinic sera were used in the present work in order to determine eventual wider ranges of relationships among Enterobacterial species of which the main antigens are the proteins (4). Interferences with polysaccharide-carrier proteins in somatic conjugates of bacteria were also eliminated by the use of antiproteinic sera. Since these sera precipitate almost indiscriminately against heterologous proteins the initial sera had to be absorbed in order to determine the eventual specific and common induced antibodies. In this report we present results concerning: S. typhi, S. enteritidis and E. coli. It appears, from the immunochemical analysis, that the proteins isolated from these species are mixtures with specificities for both Salmonellae and E. coli. The proteins from E. coli contain free proteins with Salmonella specificities of which the corresponding induced antibodies are easily removed by absorption with Salmonella protein; specific antibodies for E. coli are abundant in the absorbed E. coli sera.
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The proteins from S. enteritidis are mixtures of proteins with E. coli specificities, proteins with common Salmonellae specificities and a specific protein for S. enteritidis which was identified in all the heterologous absorbed sera. In contrast, a specific protein for S. typhi could not be identified; the mixture of proteins isolated from S. typhi contains proteins with E. coli specificity and with common Salmonellae specificities only. Materials and Methods The sera to proteins from S. typhi 0 901 , S. enteritidis and E. coli 0126 are those used in our previous work (7). The proteins were prepared as usual (1): 5 gr. acetone-dried bacteria were suspended in 100 cc veronal buffer (pH 8.4) and maintained for 48 hours at 37°C with frequent stirring. After discarding the bacteria by centrifugation, the proteins present in the clear supernatant are precipitated with trichloracetic acid (final cone. 10%) For purification, the deposited proteins are suspended in distilled water and solubilized at pH 7-7.4 with dilute NaOH; the insoluble material is discarded and 2-3 more reprecipitations and solubilizations are performed, in order to eliminate eventual traces of somatic conjugates, before dialysis and lyophilisation of the proteins. Because of the well known differences in the immune responses of the rabbits, aIiquots of the same serum were used for absorptions with heterologous proteins and the absorbed sera were tested in comparison with the initial serum. The sera, necessarily diluted by absorptions were readjusted to the initial volume by dialysis against Carbowax. Agar-gel diffusion was used for the immunochemical analysis of the total and absorbed sera; the absorptions are laborious and 5-6 consecutive absorptions were necessary for the exhaustion of the sera of heterologous antibodies. Results and Discussion The immunochemical analysis of the sera prepared with proteins from: S. typhi, S. enteritidis and E. coli 0 126 and consecutively absorbed with the respective heterologous proteins showed some unexpected results. These could not be observed with antibacterial sera, in which due to strong competitions not all the antigens of a strain induce respective antibodies (2), nor could these results be perceived in unabsorbed sera in which numerous superimposed precipitation lines are given, against the total sera, by most of the tested heterologous proteins. The materials isolated from S. typhi, S. enteritidis and E. coli appear to be mixtures of proteins with Salmonella and E. coli specificities. The absorption of the serum to proteins from S. typhi 0 901 with the proteins from two E. coli strains (055 and 0126) removed different amounts of E. coli antibodies and left, in the absorbed sera, small quantities of antibodies induced against common proteins to S. enteritidis and the homologous S. typhi (Fig. 1). The absorption of the anti E. coli serum with proteins from S. typhi removed the antibodies induced against free proteins of S. typhi present in the mixture of E. coli proteins; the absorbed E. coli serum precipitated against the specific proteins of 3 different strains of E. coli: 055' 0 126, Om (Fig. 2). The serum to S. typhi proteins, which initially precipitated numerous heterologous proteins from Salmonellae, by numerous superimposed lines, did not react, after absorption with proteins from S. enteritidis, against the homologous antigen; very faint precipitation lines still reacting, in agar-gel, were directed against common determinants (Fig. 3).
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Fig. 1. Precipitations of proteins from S. typhi and S. enteritidis against the anti S. typhi serum absorbed with proteins from E. coli. I = serum to proteins from S. typhi 0 901 ; I a = the serum I absorbed with proteins from E. coli 0,,; I b = the serum I absorbed with protein from E. coli 0126 II = serum to proteins from S. enteritidis a = proteins from E. coli 0" b = proteins from E. coli 0 126 e = proteins from S. enteritidis t = proteins from S. typhi 0 901
Fig. 2. Absorptions of sera to E. coli 0 ,2 , and to S. typhi 0 901 proteins with respective heterologous proteins, removed the antibodies induced against the free proteins present in the mixtures of both species. I = serum to proteins from E. coli 126 Ia = serum to proteins from E. coli 126 absorbed with proteins from S. typhi II = serum to proteins from S. typhi IIa = serum to proteins from S. typhi absorbed with proteins from E. coli 0 55 a = proteins from S. typhi 0 901 ; b = proteins from E. coli 126 c = proteins from E. coli 0 50 ; d = proteins from E. coli 1l9
188
C.Barber
o
® G)
;0@Ji 0WI 0 0GG) Fig. 3. The absorption of sera to proteins from S. typhi with S. enteritidis proteins removed all the antibodies induced by the immunizations; traces of precipitating antibodies, still present in the absorbed sera, are directed against common determinants. I = serum to proteins from S. typhi 0 901 Ia = serum to proteins from S. typhi 0 901 absorbed with proteins from S. enteritidis a = proteins from S. enteritidis; b = proteins from S. typhi c = proteins from S. typhimurium; d = proteins from S. paratyphi B e = proteins from E. coli 0 55 ; f = proteins from S. kentucky g = proteins from S. choleraesusis
The antigens of S. gallinarum were found earlier (3, 5) to be only a part of S. enteritidis antigens; since protection in chickens are obtained only with living bacteria (6) we assumed that other antigens must be synthesized in the birds beside those obtained on artificial media. The fact that S. typhi shares all its determinants with S. enteritidis, when grown on artificial media, seems to us significant since "in vivo" these species behave differently. The proteins from S. enteritidis induced, during similar immunizations, antibodies against numerous determinants, in addition to a specific anti-So enteritidis antibody. Aliquots of the same serum absorbed with proteins from different species of Salmonellae removed corresponding heterologous antibodies but always the specific anti S. enteritidis antibody was present in the absorbed sera (Fig. 4). Sera of the rabbits were, again and again, absorbed with heterologous proteins, with repeated confirmations of the fact that S. enteritidis
Fig.S. Confirmation, with different absorbed sera, of the absence of a specific S. typhi antigen in contrast to the existence of the specific S. enteritidis induced antibody. I = serum to proteins from S. typhi 0 901 Ia = serum to proteins from S. typhi 0 901 absorbed with proteins from E. coli 126 II = serum to proteins from E. coli 0 126 III = serum to proteins from S. enteritidis absorbed with proteins from S. paratyphi B t = proteins from S. typhi 0 901 a = proteins from E. coli 126 s = proteins from S. choleraesuis e = proteins from S. enteritidis
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Fig. 4. The absorption of aliquots of the same S. enteritidis serum with heterologous proteins, while removing heterologous antibodies according to the relationship of the absorbing antigens, leaves in all the sera the specific antibody induced by S. enteritidis specific protein. I = serum to proteins from S. enteritidis Is = the serum absorbed with proteins from S. choleraesuis IPB = the serum absorbed with proteins from S. paratyphi B It = the serum absorbed with proteins from S. typhi 0 901 E = proteins from S. enteritidis S = proteins from S. choleraesuis t = proteins from S. typhi 0 901 PB = proteins from S. paratyphi B
Fig. 5 13
Zbl. Bakt., 1. Abt. Orig. A 246
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synthesizes a specific protein in contrast to S. typhi, in which there are only common Salmonellae proteins and proteins with E. coli specificities. The abundance of antibodies specific for E. coli was evident in all the total and absorbed anti-So typhi and S. enteritidis sera (Fig. 1,2,5). Among the actual analyzed species, S. typhi as a human pathogen has "in vivo" a behaviour that is quite different from that of either S. enteritidis or E. coli. Our results, proving that in the S. typhi grown on artificial media a specific antigen is not synthesized, provide an explanation for the ineffectiveness of mass-vaccinations with S. typhi. References 1. Barber, C.: Le Tampon-Veronal, moyen d'extraction des antigenes bacteriens. Arch. roum. de Path. expo 20 (1961) 541-543 2. Barber, C. and E.Eylan: Naturally occurring Competition between Homologous Polysaccharides and Proteins of Bacteria. ZbI. Bakt. Hyg., 1.Abt. Orig. A 222 (1972) 90-95 3. Barber, C. and KEylan: The Unfortunate Role of Precedent in Bacteriology. II. Unrelated Serological Specificities of the Polysaccharides from S. typhi and S. gallinarum Sharing Factors 9.12. ZbI. Bakt. Hyg., 1. Abt. Orig. A 236 (1976) 83-88 4. Barber, C. and E.Eylan: The Unfortunate Role of Precedent in Bacteriology. 1. The main Antigens of Salmonellae: the Proteins. ZbI. Bakt. Hyg., 1.Abt. Orig. A 234 (1976) 53-59 5. Barber, C. and KEylan: Salmonella gallinarum - Salmonella enteritidis Relationship in Rabbits. ZbI. Bakt. Hyg., 1.Abt. Orig. A 237 (1977) 201-206 6. Barber, C. and KEylan: Production of Precipitating Antibodies in Chickens Infected with Salmonella gallinarum. ZrI. Bakt. Hyg., 1. Abt. Orig. A 237 (1977) 207-212 7. Barber, C. and E.Eylan: The Numerous Common Antigens of Enterobacteriaceae. ZbI. Bakt. Hyg., 1. Abt. Orig. A 244 (1979) 251-259 Dr. Cella Barber, Dept. of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv, Israel