TYPING GROUP A HEMOLYTIC STREPTOCOCCI BY M PRECIPITIN REACTIONS IN CAPILLARY PIPETTES

Toxic Shock Syndrome (TSS) Caused by Group A Streptococcus: Novel Insights Within the Context of a Familiar Clinical Syndrome

The emergence of invasive infections attributed to group A Streptococcus (GAS) infections, has resurged since the 1980s. The recent surge in reports of toxic shock syndrome due to GAS in Japan in 2024, while sensationalized in the media, does not represent a novel infectious disease per se, as its diagnosis, treatment, and prevention are already well-established. However, due to signs of increasing incidence since 2011, further research is needed. Health authorities in neighboring countries like The Republic of Korea should not only issue travel advisories but also establish meticulous surveillance systems and initiate epidemiological studies on the genotypic variations of this disease while awaiting various epidemiological research findings from Japan.

An Outbreak of Fatal Nosocomial Infections Due to Group A Streptococcus on a Medical Ward

Group A streptococcus is an uncommon but important cause of nosocomial infections. Outbreaks of infection most often have occurred in surgical or obstetrical patients. We describe an outbreak of severe group A streptococcal infections that occurred on a medical unit of a community hospital. Within an 8-day period, three patients developed fatal nosocomial skin and soft-tissue infection due to group A streptococcus. Three nurses who had provided care to one or more of these patients subsequently developed strepto-coccal pharyngitis, and three other nurses were treated with antibiotics for pharyngitis (cultures not obtained). Patient isolates were serotype M-nontypeable, T-11, opacity factor-positive, and shared identical DNA profiles when typed by pulsed-field gel electrophoresis; staff isolates were not available for typing. To prevent further spread of infection, the ward was closed to new admissions, and symptomatic staff were treated with antibiotics and relieved of patient-care duties. This outbreak demonstrates the ability of group A streptococcus to spread rapidly in a hospital setting and to cause severe life-threatening disease in hospitalized patients.

PRECIPITATION AND AGGLUTINATION TESTS WITH THE HEMOLYTIC STREPTOCOCCUS. TITRATION OF "M" AND "T" ANTI-BODIES IN HUMAN SERA

While "M" and "T" antibodies can be demonstrated in low titre in human sera, an almost complete absence of specificity seems to indicate an apparent lack of correlation with current or past streptococcal illness. In the present study, agglutination and precipitation tests on patient's sera, using known "T" and "M" antigens, appear to have little value in determining the antigenic relationship of the streptococci involved in infection. Moreover, no correlation could be shown between the amounts of "M" antibody and of "T" antibody present in the different sera. It is obvious that further work is needed. With a greater degree of purification of "M" and "T" and the elimination of non-specific substances, it may ultimately be possible to demonstrate the development of significant type-specific antibodies in human sera.

THE PROPERTIES OF T ANTIGENS EXTRACTED FROM GROUP A HEMOLYTIC STREPTOCOCCI

1. T antigens of group A hemolytic streptococci have been obtained in soluble form by digestion of the bacterial cells with pepsin or trypsin. Large quantities of this antigen were readily extracted from type 1 strains, whereas only small amounts could be obtained from strains of other types. 2. The T antigen, prepared in this way from a type 1 strain, was partially purified by chemical precipitation and further enzymatic digestion. An active fraction, apparently protein in nature, was separated electrophoretically at pH 7.00. The separated material, pooled and analyzed at the same pH, gave only a single peak. The isoelectric point of this substance was about pH 4.50. An elementary analysis was obtained. Although the T antigen was resistant to digestion with proteolytic enzymes and ribonuclease, it was readily inactivated by heat, especially in acid media and in strong salt solutions. The serological activity of this purified T substance was lost after exposure to ultraviolet radiation. 3. Analysis by means of the ultracentrifuge showed that the material was polydisperse and therefore probably impure. 4. The soluble form of the T substance was active in the precipitin reaction, in the fixation of complement, in inhibition of T agglutination, and as an antigen when injected into rabbits. The antibodies produced did not protect mice against infection with virulent strains of hemolytic streptococci containing the same T antigen. 5. The immunological specificity of T antigen in soluble form is the same as that of the T antigen in the intact streptococcus from which it was derived.

A PROTEOLYTIC ENZYME PRODUCED BY GROUP A STREPTOCOCCI WITH SPECIAL REFERENCE TO ITS EFFECT ON THE TYPE-SPECIFIC M ANTIGEN

1. Group A streptococci sometimes produce in broth culture an extracellular proteolytic enzyme. 2. Under suitable cultural conditions the enzyme has been demonstrated in representative cultures of most of the Griffith types. Its production by a given strain may be suppressed by serial passage through mice and the variant so produced has been found to maintain this change in character on subculture in artificial media. 3. Under certain conditions, the enzyme attacks the type-specific M antigens of all the group A streptococci so far tested, with the exception of that of type 28. The enzyme exhibits its maximal activity at 37 degrees C.: Extracts made from enzyme-producing cultures which have been grown at this temperature lack the M antigen; enzyme-producing strains may sometimes be induced to yield M substance in extracts by culturing the streptococci at 22 degrees C. Cultures which, when grown at 37 degrees C. yield M substance in extracts, do not produce the enzyme. 4. Human and rabbit fibrin are attacked and streptococcal fibrinolysin is also inactivated by the enzyme. Other susceptible substrates include casein, milk, gelatin, and benzoyl-l-arginineamide but not l-leucylglycylglycine. 5. The general properties of the enzyme resemble those of papain and some of the cathepsins: It is active under the reducing conditions produced in broth cultures by the presence of living bacteria; it is also activated by substances which reduce disulfide to sulfhydryl groups, e.g. potassium cyanide, cysteine, glutathione, and thioglycollic acid, but it is not activated by ascorbic acid. The enzyme is inactivated by iodoacetic acid and also by normal rabbit or mouse serum.

STUDIES ON A NON-HEMOLYTIC STREPTOCOCCUS ISOLATED FROM THE RESPIRATORY TRACT OF HUMAN BEINGS : II. IMMUNOLOGICAL CHARACTERISTICS OF STREPTOCOCCUS MG

The results of studies on the antigenic structure and immunological specificity of a non-hemolytic streptococcus, designated streptococcus MG, are described. Evidence is presented to show that this microorganism possesses a capsule and that this structure contains a polysaccharide antigen which is responsible for the type specific serological reactions obtained with streptococcus MG.

STUDIES ON STREPTOCOCCAL FIBRINOLYSIS : V. THE IN VITRO PRODUCTION OF FIBRINOLYSIN BY VARIOUS GROUPS AND TYPES OF BETA HEMOLYTIC STREPTOCOCCI; RELATIONSHIP TO ANTIFIBRINOLYSIN PRODUCTION

A method for the measurement of fibrinolysin production by beta hemolytic streptococci is described. The test was shown to be highly accurate in that repeated determinations showed only small variations. A study of 766 strains of beta hemolytic streptococci isolated from normal soldiers and patients with respiratory disease showed that fibrinolysin was produced by Lancefield groups A, C, and G, and, in addition, by a few strains of groups B and F. Group A streptococci produced more fibrinolysin on the average than the other groups. The median titers were 117 for group A, 61 for group C, and 20 for group G streptococci. In a study of 388 typed group A streptococci from different subjects the fibrinolytic capacity of an organism was shown to be related to the serological type. The importance of this observation in relation to the role of streptococcal fibrinolysis in infections is discussed. Finally, it was demonstrated that strains of streptococci which produced large amounts of fibrinolysin were capable of stimulating antifibrinolysin formation in patients whereas strains that produced small amounts only occasionally caused antibody formation.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : I. EFFECTS OF PROTEOLYTIC ENZYMES ON STREPTOCOCCAL CELLS

1. Proteolytic enzymes destroy the type-specific M antigen of group A hemolytic streptococci not only when the M substance is contained in cell-free extracts but also when it is a component of the living cell. 2. The injection of enzyme-treated cultures into rabbits fails to induce the formation of M antibodies, but does result in the production of T antibodies and, therefore, provides a method of preparing anti-T sera free from M antibodies. 3. Exposure to these enzymes does not kill the bacteria. Virulence and the ability to form M substance are restored on subculture and animal inoculation. 4. The study of the effect of proteolytic enzymes on group A hemolytic streptococci provides new techniques for analyzing the antigenic composition of these microorganisms.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : III. TYPES WITH SEROLOGICALLY IDENTICAL M BUT DISTINCT T ANTIGENS: TYPES 10 AND 12

1. In this study a series of experiments showing the antigenic relationship of type 10 and type 12 group A hemolytic streptococci is reported. Agglutinin, precipitin, and passive protection tests with unabsorbed and reciprocally absorbed antisera were employed to show that representative type 10 and 12 strains contain serologically identical M antigens but unrelated type-specific T antigens. 2. Twenty-three other strains of group A hemolytic streptococci previously classified as either type 10 or type 12, collected from various sources, were shown to have an antigenic composition similar to one or the other of the two representative type strains. 3. The relationship of the two specific antigens, M and T, must be considered when any method employing the agglutinin reaction for the typing of group A hemolytic streptococci is used.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : IV. RELATED T BUT DISTINCT M ANTIGENS IN TYPES 15, 17, 19, 23, 30, AND IN TYPES 4, 24, 26, 28, 29, 46. IDENTIFICATION BY SLIDE AGGLUTINATION

1. The occurrence of closely related T antigens in the series composed of types 15, 17, 19, 23, and 30 accounts for most of the cross reactions observed among these types. Similarly T antigens, unrelated to the first series but mutually related, occur in a second series comprising types 4, 24, 26, 28, 29, and 46. 2. Matt variants of each of the eleven types studied possess type-specific M antigens demonstrable either by precipitin or agglutinin reactions. 3. In seven of these types, strains have been encountered which do not possess the T antigen usually associated with the type in question. 4. Procedures are outlined in the appendix for preparing specific antisera for the classification of these types by the slide agglutination technique.

BACTERIOSTATIC EFFECT OF HUMAN SERA ON GROUP A STREPTOCOCCI : I. TYPE-SPECIFIC ANTIBODIES IN SERA OF PATIENTS CONVALESCING FROM GROUP A STREPTOCOCCAL PHARYNGITIS

1. Type-specific antibodies were demonstrated by the indirect bacteriostatic test in sera from human adults convalescing from group A streptococcal infection of the upper respiratory tract. The time of appearance of the antibodies varied from 3 to 5 weeks; and they persisted in 2 patients for at least 37 weeks after the onset of the infection. 2. The specificity of the antibody response in one serum was tested with strains of 7 heterologous types; in another, with 6; and in the third, with 2; but in no instance were cross-reactions observed. Moreover, each convalescent serum showed approximately equal bacteriostasis for 7 different strains of the same type as that which caused the infection. 3. The antibodies were specifically absorbed from the serum by homologous heat-killed streptococci, but not significantly by strains of heterologous types. 4. The specific M antigen of the streptococcal cell with its respective antibody, and not the T substance, appeared to be concerned in the reaction. 5. In spite of numerous technical difficulties inherent in the method, this bacteriostatic test provides a useful procedure for studying type-specific immunity in streptococcal infections.

Evidence for rare capsular switching in Streptococcus agalactiae

The polysaccharide capsule is a major antigenic factor in Streptococcus agalactiae (Lancefield group B streptococcus [GBS]). Previous observations suggest that exchange of capsular loci is likely to occur rather frequently in GBS, even though GBS is not known to be naturally transformable. We sought to identify and characterize putative capsular switching events, by means of a combination of phenotypic and genotypic methods, including pulsed-field gel electrophoretic profiling, multilocus sequence typing, and surface protein and pilus gene profiling. We show that capsular switching by horizontal gene transfer is not as frequent as previously suggested. Serotyping errors may be the main reason behind the overestimation of capsule switching, since phenotypic techniques are prone to errors of interpretation. The identified putative capsular transformants involved the acquisition of the entire capsular locus and were not restricted to the serotype-specific central genes, the previously suggested main mechanism underlying capsular switching. Our data, while questioning the frequency of capsular switching, provide clear evidence for in vivo capsular transformation in S. agalactiae, which may be of critical importance in planning future vaccination strategies against this pathogen.

Serological and biochemical relationships between the alleged avirulent variant ofCorynebacterium kutscheriand streptococci of group N

Morphological, biochemical and serological observations suggested that no close relationship existed betweenC. kutscheriand its alleged avirulent variant isolated from mice at the Rockefeller University. However, both capillary and double diffusion precipitin reactions showed the alleged variant to be a streptococcus of group N, indistinguishable from that previously isolated from Rockefeller University mice.

Production of proteinase by hemolytic streptococci in various clinical conditions

The proteinase activity of strains of group A streptococci isolated from patients in acute and convalescent phases of illness was found to be remarkably constant. Sulfadiazine therapy of patients did not affect proteinase production by the infecting streptococci. The ability to produce streptococcal proteinase would appear to be related to the strain and not necessarily to the serological type. No relationship could be found between the capacity of group A streptococci of different serological types to produce proteinase and the various clinical responses to infection with these microorganisms.

Protective effect of hyaluronidase and type-specific anti-M serum on experimental group A streptococcus infection in mice

Five strains of encapsulated group A streptococci of different serological types, each with a glossy and a matt variant, were studied to compare the rôles of the M substance and the hyaluronic acid capsule in virulence of these microorganisms. The results indicated that both contribute to the virulence of group A streptococci but that the M antigen is the more fundamental factor. Encapsulated variants, both glossy and matt, were slightly less susceptible to phagocytosis than those from which the capsule had been removed with hyaluronidase. Glossy variants, containing no M substance, were readily phagocyted; matt, M-containing variants were resistant to phagocytosis except in the presence of anti-M serum when they became fully susceptible. Only the M-containing, matt strains were mouse-virulent. Mice were protected against infections with these strains: (a) By removal of the capsule with hyaluronidase, which resulted in slight protection, but only against 10 M.L.D. Early and intensive treatment was required to produce this effect; i.e., simultaneous injection of enzyme and streptococci followed by prolonged enzyme therapy. (b) By a single injection of anti-M serum administered the day before inoculation of the streptococci, which resulted in protection against 100,000 M.L.D. (c) By combined use of enzyme and anti-M serum, an additive effect of the two protective agents occurred, which resulted in protection against 1,000,000 M.L.D.

Variation occurring in group A streptococci during human infection; progressive loss of M substance correlated with increasing susceptibility to bacteriostasis

A study was made of the variation occurring in group A streptococci during the natural course of infection in man. From 54 patients with 56 different group A streptococcal infections of the upper respiratory tract, 251 strains of streptococci, isolated at weekly intervals following infection, were tested for their capacity to resist the bacteriostatic action of normal human blood. In 52 of the infections the streptococci were of recognized serological types and were also tested for variation in their ability to produce the type-specific M protein antigen. Strains isolated in the 1st week of infection were uniformly highly resistant to bacteriostasis and elaborated large amounts of M substance. In 42 per cent of the 52 infections, strains isolated in the convalescent and carrier stages showed an increasing susceptibility to bacteriostasis correlated with a progressive loss of M substance; whereas in the remaining 58 per cent resistance to bacteriostasis and the capacity to produce M protein were maintained throughout the observation period. In 3 different infections, the streptococci became so degraded that no M protein could be demonstrated in acid extracts of these variants. Concomitantly these strains became highly susceptible to bacteriostasis. Spontaneous reversion did not occur, but serial mouse passage reestablished these functions. These degraded variants had the same T antigen as their respective original strains. No evidence was obtained that variation of group A streptococci in resistance to bacteriostasis or in the ability to produce the type-specific M antigen was associated (a) with the appearance of type-specific bacteriostatic antibodies; (b) with any particular serological type of streptococcus; (c) with the production of streptococcal proteinase which digests the M protein; (d) with the therapeutic administration of sulfadiazine; or (e) with the development of complications. The possible relationship of these observations to the problem of the "dangerous carrier" of group A hemolytic streptococci is discussed.

The inhibitory effect of polysaccharide on mumps virus multiplication

Polysaccharides derived from type-specific Friedländer bacilli cause inhibition of the multiplication of mumps virus in the allantoic sac of the chick embryo. As little as 5 µg. of polysaccharide is effective as an inhibitor. Inhibition of multiplication is obtained when polysaccharide is injected as long as 4 days after inoculation of virus. Chemical studies have shown that the structural configurations of the polysaccharide responsible for specific serological activity are not identical with those which determine the inhibitory effect relative to mumps virus. The possible mechanisms of the inhibition of viral multiplication by means of polysaccharides are discussed.

A type-specific protein from pneumococcus

The isolation and characterization of a type-specific M protein from pneumococcus are described. This protein is similar chemically in all respects studied to the M proteins of group A streptococci. No immunological crossreactions have been observed, however, between M proteins of the two species. Strains of capsular type I pneumococcus have been encountered which contain different M proteins. The same is true for capsular type II pneumococcus. It is apparent, therefore, that the capsular polysaccharides and M proteins can vary independently of each other.

Extraction of Cell-Wall Polysaccharide Antigen from Streptococci

Slade, Hutton D. (Northwestern University Medical School, Chicago, Ill., and Max-Planck Institut für Immunbiologie, Freiburg, Germany). Extraction of cell-wall polysaccharide antigen from streptococci. J. Bacteriol. 90:667-672. 1965.-The carbohydrate grouping antigens in the cell walls of streptococci belonging to groups A, E, G, L, and T were extracted with 5% trichloroacetic acid at 90 C. The antigens were removed also from dry whole cells by extraction with trichloroacetic acid followed by treatment with phenol-water. Details of the methods are presented. The antigens obtained by use of either of these procedures were suitable for studies on immunological specificity and chemical structure. Quantitative enzymatic and chemical analyses of two group E antigens and one group T preparation showed the presence of l-rhamnose (22 to 44%), d-glucose (7 to 22%), d-galactose (T antigen only, 26%), glucosamine (2 to 16%), and galactosamine (T antigen only, 3%). In addition, analyses of A and G antigen preparations are presented. The protein and phosphate content of the A and E antigens were about 1% each. Quantitative precipitin curves of these antigens are presented.

Characterization of group A streptococci (Streptococcus pyogenes): correlation of M-protein and emm-gene type with T-protein agglutination pattern and serum opacity factor

Strain characterization of group A streptococci (GAS) has traditionally been based on serological identification of M protein. Additional tests to determine T-protein serotype and production of streptococcal serum opacity factor (SOF) provide important information both to aid in and to supplement M-protein serotyping. Advances in DNA-sequencing technology in the late twentieth century resulted in the development of a method for determining the M type of GAS from the sequence of the gene encoding M protein, the emm gene. Although emm-sequence typing has largely replaced M typing in many laboratories, information provided by T typing and SOF determination continues to provide valuable supplementary information for strain characterization. A comprehensive summary of the correlation of T pattern and SOF production with M type was last published in 1993, several years before emm typing became widely available. Since then, the ease of M-type identification afforded by emm typing has resulted in an increase in the number of confirmed M/emm types of more than 50 %. However, comprehensive information about T-protein serotype and the correlation of SOF production with these new M/emm types is not widely available. This report presents a comprehensive summary of this information, not only for newly described types, but also updated information for previously described types. This information was extracted from combined records from streptococcal reference laboratories at the University of Minnesota and at the Centers for Disease Control and Prevention in Atlanta. Data from more than 40,000 strains (representing uncomplicated GAS infections, systemic invasive infections and strains associated with non-suppurative sequelae, collected from the US and diverse locations worldwide) were analysed.

The crystallization and serological differentiation of a streptococcal proteinase and its precursor

Grown in dialysate broth at a pH between 5.5 and 6.5, some strains of group A streptococci elaborate the precursor of a proteolytic enzyme. Within this range of hydrogen concentration the precursor is also produced when the streptococci are suspended in a peptone dialysate containing glucose and incubated at 37°C. The precursor does not appear to be produced at a neutral or alkaline reaction. Methods are described whereby the precursor and proteinase have been isolated in crystalline form. The precursor crystallizes from half-saturated ammonium sulfate at pH 8.0 and a temperature of 22°C. or higher; the proteinase crystallizes from 0.15 saturated ammonium sulfate at pH 8.0 but does so most readily at refrigerator temperature. The degree of purification achieved by these procedures is discussed. The activity of purified preparations of the precursor and of proteinase has been tested against α-benzoyl-l-arginineamide and, with this as a substrate, the conversion of precursor to proteinase by autocatalysis or by trypsin has been confirmed. Immunological experiments are described, the results of which provide evidence of the distinct antigenic specificity of the precursor and proteinase; the conversion of precursor to proteinase has been followed by means of serological tests.

Group A Streptococcal Pharyngitis Serotype Surveillance in North America, 2000–2002

Geographic and interseasonal heterogeneity of pharyngeal group A streptococcal (GAS) genotypes (emm types) is poorly characterized. We evaluated emm type and subtype distribution among pediatric pharyngitis isolates obtained from 9 sites in the United States during 2000-2001 (year 1) and from 10 sites in the United States and 1 site in Canada during 2001-2002 (year 2). The 7 predominant types were the same in both years, although their order changed. emm 12, 1, and 28 accounted for 49.2% of year 1 isolates, and emm 1, 12, and 4 accounted for 47.1% of year 2 isolates; 6 types accounted for 72.1% in year 1 and 69.4% in year 2. From year 1 to year 2, the proportions of emm 12 and 28 decreased and emm 1 and 6 increased. Striking intersite and interseasonal variations in the distribution of predominant emm types were observed. We conclude that the most-predominant GAS genotypes were similar for each year despite fluctuations, that intersite and intrasite variations in the distribution of emm types were apparent, and that emm type surveillance is needed as M protein vaccine development proceeds.

Post-streptococcal acute glomerulonephritis in Chile--20 years of experience

In order to characterize the epidemiological and clinical picture of post-streptococcal acute glomerulonephritis (PSAGN), a prospective study was designed to investigate all admissions to a general hospital of a local health service in Chile. The protocol included the investigation of previous streptococcal infections (SI), clinical symptoms and signs, socioeconomic situation (SES), throat and skin swabs for the isolation of group A beta-hemolytic streptococci, sequential determination of serum antistreptolysin O (ASO) titer, anti-DNAase B antibodies, and C3. During the 20 years studied, 926 cases were admitted (56% males). Incidence showed an endemic period (EP) 1980-1983, an epidemic outbreak (EO) 1984-1989, and a late period (LP) 1990-1999, with a rate per 100,000 inhabitants of 6.2, 13.2, and 1.7, respectively. The clinical picture was similar in the three periods. SES was homogeneous, with 80% of the population in low and middle-low categories. The average size of the family was 6.9 compared with 4.8 in the general population. Pyoderma was more frequent than pharyngeal infection, and more so during the EO. The isolation rate of group A beta-hemolytic streptococci from the pharynx was 20% compared with 60% from skin swabs. During EP, the most prevalent serotypes were T14-M0 and T1-M1 from the pharynx and TImp19-M0 from the skin. During EO, T14-M0 was more prevalent (30%). M or T classification was possible in EP and EO in 80%-85% of all strains isolated from the two locations. Significant titers for ASO and anti-DNAase B were found on admission: 55% and 75%, respectively. Both tests allowed identification of 100% of previous SI. In conclusion, the incidence of PSAGN had an uneven trend during the observed period. EO was mainly due to skin infection and a predominance of one serotype, T14-MO, was observed. After the EO, the yearly rate gradually decreased from 13.2 in 1988 to 0.0 in 1999, a rate similar to that of industrialized nations.

The antistreptococcal property of milk. I. Some characteristics of the activity of lactenin in vitro; the effect of lactenin on hemolytic streptococci of the several serological groups

The measurement in vitro of lactenin, the antistreptococcal substance of milk, is affected by the size of the inoculum, the temperature of incubation, and the type of medium employed. Hemolytic streptococci belonging to the several serological groups vary in susceptibility to lactenin. All group A streptococci, regardless of type, are highly sensitive to it, and milk receiving a small inoculum sterilizes itself within 48 hours or less. By contrast, most strains of groups B, C, D, and E, although they may temporarily be inhibited, ultimately achieve full growth. Strains belonging to groups F, G, H, K, and L vary in sensitivity, some being fully inhibited and others achieving full growth. When streaked on the surface of milk-agar plates and examined at the end of 24 hours the streptococci fall into two classes: sensitive strains which do not produce visible colonies on the plate, and resistant strains which grow excellently. Very few strains show an intermediate degree of sensitivity. Human and goat milk contain an antistreptococcal principle which appears to be the same as the lactenin of cow milk, since streptococci which are inhibited by milk from one species are inhibited by milk from the others, and vice versa.

A mucoprotein derived from human urine which reacts with influenza, mumps, and Newcastle disease viruses

A mucoprotein, present in normal human urine, has been isolated and obtained in a state of a high degree of purity. A number of the biological, chemical, and physicochemical properties of the substance have been studied. From the results obtained in the present investigation and those reported in succeeding papers (34, 35) it appears that the mucoprotein has a high molecular weight, i.e., of the order of 7.0 x 10⁶, consists of thread-like molecules which have axial ratios of approximately 100, and is specifically antigenic. This substance, which appears to be free of contaminating material, possesses in extraordinary degree the capacity to react with influenza, mumps, and Newcastle disease viruses. At equilibrium, with influenza virus, the minimal amount of the substance capable of giving a demonstrable reaction with one hemagglutinating unit of virus appears to be about 0.0003 µg. The mucoprotein is altered by preparations of influenza viruses and its capacity to react with these agents or others is lost. The kinetics of the inactivation process brought about by influenza viruses is in accord with those of well known enzyme-substrate systems. With the exception of the capacity to react with viruses, altered mucoprotein did not differ from the native substance relative to any of the properties examined in the present study. That certain physicochemical properties of the altered mucoprotein are different from those of the native substance is demonstrated in succeeding papers (34, 35).

An electrophoretic study of a streptococcal proteinase and its precursor

An electrophoretic study of crystalline preparations of a streptococcal proteinase and its precursor established their isoelectric points at pH values of 8.42 and 7.35 respectively (ionic strength 0.10). Preparations of the proteinase appeared to be electrophoretically homogeneous over a pH range of 5 to 8.5. Precursor preparations contained a relatively low concentration of the active enzyme visible as a separate peak in electrophoretic patterns of sufficiently concentrated solutions. Autocatalytic conversion of precursor to active enzyme was complete and resulted in a corresponding change in the electrophoretic pattern. Treatment of precursor preparations with trypsin produced incomplete conversion to the active enzyme and resulted in the formation of a modified precursor protein. This differed from the parent substance in electrophoretic mobility and in susceptibility to trypsin, but resembled it in immunological specificity and, as previously shown, in susceptibility to conversion to active enzyme by autocatalysis. Serological reactions of precursor and active enzyme components withdrawn from the cell after electrophoresis are described. It appears that the precursor protein may have two antigenic groups, one specific, the other shared by the active enzyme which behaves as a single antigen.

Studies on non-hemolytic streptococci isolated from the respiratory tract of man; the antigenic basis for type specific reactions with streptococcus salivarius and non-levan-forming streptococci

The type specific immunological properties of certain non-hemolytic streptococci, including Str. salivarius type I and type II, present in the respiratory tract of human beings appear to be dependent upon the presence of capsular polysaccharides. The levans formed from sucrose by Str. salivarius (encapsulated S cells or non-encapsulated R variants), or by cell-free enzymes derived from these microorganisms, are indistinguishable immunologically and show no evidence of type specificity. Such levans appear to be immunologically distinct from and unrelated to the capsular polysaccharides of the microorganisms which produce them.

Preparation and properties of type-specific M antigen isolated from a group A, type 1 hemolytic streptococcus

Type-specific M antigen was extracted by heating type 1 group A streptococci at pH 2 in a boiling water bath. The protein was then purified by digestion with a preparation of crystalline ribonuclease which was free of proteolytic activity. It was further purified by fractional precipitation with (NH(4))(2)SO(4). Elementary chemical analysis of the preparation thus obtained showed an absence of phosphorus and a sulfur content of 2.46 per cent. In the ultraviolet the maximum absorption was at a wave length of 276 mmicro and the minimum at 255 mmicro. In electrophoresis experiments the preparation showed a single peak in the pH range of 3 to 9, but considerable boundary spreading was observed. The type 1 M antigen was isoelectric at pH 5.3 in sodium acetate buffer of ionic strength 0.1. The serological reactivity of the protein isolated was typical of type 1 M antigen. This protein induced the formation in rabbits of type-specific precipitins and protective antibodies. The absorption of type 1 antibacterial serum with the purified M antigen removed both the protective antibodies and the type-specific precipitins from the serum.

Variation in the group-specific carbohydrate of group A streptococci. I. Immunochemical studies on the carbohydrates of variant strains

The phenomenon of apparent loss of group-specific carbohydrate in the course of mouse passage of group A streptococci has been subjected to further study, and several additional variants showing this property have been described. The loss of group reactivity is shown to be due to an alteration in the chemical structure and serological specificity of the cell wall carbohydrate. This alteration appears to be essentially the same in each of the variants available for study. The carbohydrate of the variant strains (V) contains the same two monosaccharide components as the group A carbohydrate (A), but they are present in different proportions. Precipitating sera reactive with V carbohydrate have been prepared, and the A and V carbohydrates have been compared by qualitative and quantitative precipitin analysis. A second type of variation has been encountered during mouse passage. This variation is characterized by the occurrence of a cell wall carbohydrate (I) intermediate in chemical and serological properties between the A and V carbohydrates. The I carbohydrate reacts with both A and V antisera and does not appear to be a simple mixture of A and V carbohydrate. Similarly, antisera against the intermediate strain contain antibodies reactive with both A and V carbohydrates, and evidence is presented indicating that in part this represents antibody with double specificity.

The structure of the antigenic polysaccharide produced by Eubactrium saburreum T15

The antigenic polysaccharide was obtained from the cell wall of Eubacterium saburreum strain T15 by trypsin digestion followed by gel permeation and ion-exchange chromatography. Its structure was determined using acid hydrolysis, methylation analysis, and 1D and 2D NMR spectroscopy. It contained L-threo-pent-2-ulose (Xul), D-fucose (Fuc), and D-glycero-D-galacto-heptose (Hep) in 2:3:3 ratio. Methylation analysis indicated an octasaccharide repeating-unit containing five branches. The 1H and 13C signals in NMR spectra of the sugar residues were assigned by COSY, HOHAHA, and HMQC 2D experiments, and the sequence of sugar residues in the repeating unit was determined by NOESY and HMBC experiments. The polysaccharide also contains two O-acetyl groups in the repeating unit, located on the Hep residue. The repeating structure can be written as: [see text for equation]. This is a novel structure in bacterial cell-wall polysaccharides from Gram-positive bacteria.

Epidemiological usefulness of anti-opacity factor antibody screening in schoolchildren

The presence of the anti-opacity factor (anti-OF) antibody (Ab) in the serum used for identifying the OF antigen (Ag) type represents previous or current infection with group A streptococci (GAS) of the OF Ag type. Throat cultures were taken from 172 elementary schoolchildren in Chinju, Korea, and venous blood samples were collected at the same time to screen for the frequency of the anti-OF Ab. After isolation of GAS, the OF Ag of each GAS was identified by inhibition of the opacity reaction with recognized anti-OF sera. The anti-OF Abs in the sera were screened with the six most common OF Ag types. OF22 and OF28 were high in prevalence (28.2 and 20.5%, respectively) among OF Ag types, while anti-OF types 4, 28, and 22 were frequently identified (39.5, 29.7, and 15.7%, respectively) in the sera. Thirty-two of 39 (82.1%) OF Ag-producing GAS carriers, 25 of 34 (73.5%) GAS carriers not producing OF Ag, and 72 of 99 (72.7%) throat culture-negative children harbored the anti-OF Ab. Forty-five (26.2%) of 172 children had two different anti-OF Abs, and 11 (6.4%) had more than three anti-OF Abs. Seventy-five percent of 172 elementary schoolchildren were shown to be previously or currently infected with GAS. The percentages of children positive for the anti-OF Ab were very high regardless of the result of throat culture or OF Ag production of GAS. We could also demonstrate (i) that the prevalent strains of GAS changed according to the time span by determining the difference between the frequencies of OF Ag and anti-OF Ab and (ii) that repeated infections were not uncommon in schoolchildren, as one-third had more than two different anti-OF Abs.

Renal glomerular lesions induced by rabbit antirat collagen serum in rats prepared with adjuvant

Renal glomerular lesions were induced by rabbit serum containing antibody to rat collagen injected intravenously into rats prepared with subcutaneously administered Freund adjuvant. Neither the anti-collagen serum nor the adjuvant alone induced the lesion. The lesions were characterized by diffuse glomerular injury with swelling, shredding, and fusion of the basement membranes, crescent formation, cellular proliferation, numerous multinuclear giant cells, and capillary hyaline thrombi. Various rabbit antisera, including those against fish collagen or rat serum failed to induce the renal lesion when substituted for anti-rat collagen serum. Also, anti-rat collagen serum absorbed with its homologous antigen, native rat collagen, failed to induce the lesion. Although complete adjuvant, i.e. with mycobacteria, in which normal serum was incorporated enhanced the glomerular lesion which resulted from intravenous injection of anti-collagen serum, the incomplete adjuvant without serum was sufficient. Comparison of the renal lesions induced by anti-collagen serum with nephrotoxic nephritis induced in rats by rabbit anti-kidney serum showed that they differ histologically. Also the antisera used to produce these two renal lesions differ immunologically. Antibodies to normal rabbit serum developed in rats injected intravenously with rabbit anti-rat collagen serum after preparation with adjuvant, but not when adjuvant was omitted. The pathogenesis of the renal injury is discussed as a manifestation of an antigen-antibody reaction, with nephritis occurring only after the adjuvant-stimulated antibody to the rabbit globulin has been formed in the rat and has reacted with the rabbit anti-rat collagen already fixed by its homologous antigen in the kidney.

Studies on Streptococcus pyogenes. IV. Effect of whole cells, M and C antigens, and other components of the cell on adrenalectomized rats

Heat-killed cells of Group A streptococci caused death of the adrenalectomized rat. While the adrenalectomized rat readily succumbed to intraperitoneal infection with living cells, death was due primarily to toxicity. The normal rat was highly resistant under either condition. For studies on the toxic materials, the cells of numerous serological types of group A streptococci, and of a Group B and a Group D streptococcus, were extracted with 0.1 N HCl at 100°C. or by sonic oscillation. The extracts, containing macromolecular components, were subjected to chemical fractionation and purification. C substance and M protein of Group A streptococci released from the cell by sonic oscillation were toxic to the adrenalectomized rat in quantities of 1 mg./100 gm. rat. Death usually occurred within 2 hours. On the other hand, C substance and M protein released from the cell with HCl at 100°C. were relatively non-toxic to the adrenalectomized rat. The sonic-extracted C substance of streptococcal Groups B, C, and D was also toxic. The toxic property of the C and M preparations was neutralized in vitro in each case by group and type-specific rabbit antiserum. Heterologous antiserum was without effect. Adrenalectomized rats which received homologous antiserum 18 hours before challenge were also resistant to the toxicity of the C and M preparations. Trypsin destroyed the toxic effect of the M protein preparations and was without effect on the toxicity of the C substance. The R antigen and a nucleoprotein component of Group A streptococci, preparations of protein from Groups B and D streptococci, and coagulase from Staphylococcus aureus were all found to be essentially non-toxicic for the adrenalectomized rat. Large quantities of peptone, crystalline albumin, and rabbit serum were also without effect.