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Biomedical subjects

J Henrichsen

Publications and source records attributed to J Henrichsen.

At least 127 records · Page 7Linked to original sources

Antibody response to vaccination with pneumococcal capsular polysaccharides in splenectomized children.

In 67 splenectomized children vaccinated with a 14-valent pneumococcal capsular polysaccharide vaccine an antibody fold increase above 2 from pre- to postvaccination samples was found in 60% of all single type antibody determinations performed. The vaccine may only afford protection against 55% of those serotypes that cause serious infections in children, assuming a protective antibody level of 300 ng antibody N/ml. Our results indicate a somewhat reduced antibody response to pneumococcal vaccine in splenectomized children and suggest that pneumococcal vaccination may not be relied upon as the only kind of prophylaxis against pneumococcal infection in this patient group.

Adolescent↗

Anti-C-carbohydrate antibodies after pneumococcal vaccination.

Similar levels of naturally occurring anti-pneumococcal C-carbohydrate antibodies were found in 15 splenectomized children, 10 splenectomized adults and 12 healthy adult volunteers by enzymelinked immunosorbent assay. Vaccination with a 14-valent pneumococcal capsular polysaccharide vaccine (Pneumovax) that contains approximately 75 micrograms C-carbohydrate per dose only led to small anti-C-carbohydrate antibody increases; they were significant, however, for all three groups (p less than 0.05) but antibody fold increases were below 2 in 34 of the 37 individuals studied.

Adolescent↗

Cross-immunogenicity of pneumococcal group 9 capsular polysaccharides in adult volunteers.

Group 9 organisms (types 9N, 9A, 9L, and 9V) account for about 3 to 4% of pneumococcal disease isolates throughout the world. Types 9N and 9V comprise about 90% of the group 9 disease isolates. Type 9N is more common than type 9V in adults, and type 9V predominates in infants and children. In the United States there have been eight reported cases due to group 9 pneumococci in individuals previously vaccinated; six were type 9V and two were type 9N. To ascertain the cross-immunogenicity of group 9 polysaccharides, volunteers were injected with vaccines of monovalent types 9N, 9A, 9V, or 9L, or bivalent (9N and 9A) or trivalent (9N, 9A, and 9V) polysaccharide vaccines. Monovalent types 9N, 9V, and 9L each stimulated a 5.8- to 7.5-fold geometric mean rise, and at least 80% of the volunteers responded with a twofold or greater homologous antibody rise. Type 9V induced a 5.8-fold geometric mean rise, but only 66% of the volunteers responded with a twofold or greater homologous antibody rise. Type 9N induced only a 2.1-fold geometric increase, and only 54% of the volunteers responded with a twofold or greater rise in anti 9V antibodies. Types 9L and 9A were the most cross-immunogenic. The trivalent preparation (9N, 9A, and 9V) gave the highest geometric mean titer and seroconversion rate to each of the group 9 polysaccharides. These results suggest that the polyvalent pneumococcal vaccine with its type 9N does not induce a satisfactory anti-type 9V response and should contain additional components in order to achieve greater protection against group 9 organisms.

Adult↗

Detection of antibodies to pneumococcal capsular polysaccharides by enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay for the detection of immunoglobulin G, M, and A antibodies against each of the 14 polysaccharide antigens contained in a contemporary pneumococcal vaccine is described. A mean total antibody fold increase above 2 from prevaccination to 4 weeks postvaccination serum samples was found for all antigens in 12 healthy adults and 6 children. Fifty-five percent of all single fold increases determined were above 2 in the adults; the value was 64% in children. Type-specific polysaccharide antibody of the immunoglobulin G class was predominant in 4 weeks postvaccination serum samples. Further studies with assays such as the one described may lead to a better understanding of the immune response to pneumococcal polysaccharides in both normal subjects and patients at increased risk of pneumococcal infection.

Animals↗

Immunochemical characterization of cross-reactivity of pneumococcal group 9 capsular polysaccharide types 9N, 9A, 9L, and 9V.

The chemical composition and immunochemical characterization of the four cross-reactive pneumococcal capsular polysaccharides within group 9 (types 9N, 9A, 9L, and 9V) were investigated. Their serological reactions were studied by using unabsorbed antisera prepared by immunizing rabbits with pneumococci of each of the four group 9 capsular polysaccharide types. Type 9A antiserum showed the most extensive cross-reactions with the four group 9 polysaccharides. Absorption with type 9N, 9L, or 9V polysaccharide removed 63, 96, or 87%, respectively, of the heterologous antibodies from the type 9A antiserum. All four of the group 9 polysaccharides contained glucose, N-acetylmannosamine, and glucuronic acid. In addition, types 9N and 9L had N-acetylglucosamine, and types 9A, 9L, and 9V contained galactose. Reduction of the uronic acid residues of the type 9 polysaccharides removed most of their homologous and much of their heterologous reactivities, indicating an important role for the uronic acid component in their antigenicity. The four group 9 polysaccharide preparations had comparable molecular sizes and only traces of protein and nucleic acid. Further studies to evaluate the most protective type among the group 9 strains to be included in the current pneumococcal vaccine are discussed.

Amino Sugars↗

Pneumococcal vaccine and otitis media.

After an acute attack of otitis media 827 children aged 3 months to 6 years were assigned randomly to receive either 14-valent pneumococcal polysaccharide vaccine or a control vaccine (Haemophilus influenzae type b capsular polysaccharide). In children older than 6 months serum antibody responses to most of the vaccine polysaccharides were satisfactory. The response to type 6A was poor. Correspondingly, no clinical protection was seen below 6 months of age or against otitis media caused by group 6 pneumococci. Among the children more than 6 months old, the first 6 months after vaccination saw significantly (p < 0.001) fewer attacks caused by the pneumococal types represented in the vaccine (group 6 excepted) in those who received the pneumococcal vaccine than in those who received the control vaccine. Protection against type 19F was statistically significant (p < 0.01). The overall protective efficacy was 58%--somewhat better in children older than 2 years than in those younger. Previous attacks of otitis caused by pneumococci did not influence the protective efficacy of the vaccine.

Age Factors↗

Serotypes of group B streptococci and their relation to hyaluronidase production and hydrolysis of salicin.

A total of 252 strains of group B streptococci were serotyped and examined for their ability to ferment lactose (lac+), to hydrolyze salicin (sal+), and to produce hyaluronidase (hy+). Of these strains, 67 had been isolated from bacteremia and meningitis in infants less than 2 months old. Eighty-one strains were isolated from bacteremia and meningitis in adults, and 104 strains were from various other infections. Type III was the most common in neonatal disease, especially if isolates from cases of bacteremia in infants less than 10 days of age were not included. Only 6% of the strains were lac+. Sal+/hy+ strains were never type III, but 91% of the strains belonging to the other serotypes were sal+/hy/. Results showed that 81% of the sal+/hy- strains and 95% of the sal-/hy+ strains were type III, and sal-/hy+ strains were more than twice as frequent as sal+/hy- strains in serious neonatal infections, in contrast to the other two disease groups, in which the opposite was found to be the case. These reactions may be used as additional markers in epidemiological studies.

Adult↗

Comparison of counterimmunoelectrophoresis and the capsular reaction test for typing of pneumococci.

The capsular reaction test is recommended as the method of choice for typing of pneumococci. Counterimmunoelectrophoresis also works in most cases, but has the following definite drawbacks. (i) The polysaccharide type antigens of types 7F, 7A, 14, 33F, 33A, and 37 are neutral and therefore do not form precipitates when conventional buffers are used. (ii) Counterimmunoelectrophoresis does not permit differentiation between types within groups since many factor sera do not contain sufficient amounts of precipitating antibodies. Omniserum contains low-titered antibodies against cell wall antigens and also reacts with thioglycolate-containing broth.

Antigens, Bacterial↗

Comparative immunogenicity of group 6 pneumococcal type 6A(6) and type 6B(26) capsular polysaccharides.

The comparative immunogenicity of the two cross-reacting group 6 pneumococcal capsular polysaccharides, type 6A(6) and type 6B(26), was studied with hyperimmune rabbit typing antisera and with sera from adult volunteers injected with polyvalent pneumococcal vaccines containing either 50 mug of type 6A (U.S. designation, type 6) or 50 mug each of type 6A and type 6B (U.S. designation, type 26) polysaccharides. Both group 6 polysaccharides were linear copolymers composed of 1 mol each of d-galactose, d-glucose, l-rhamnose, and d-ribitol phosphate. They differed only in that type 6A had a rhammopyranosyl-(1 --> 3)-d-ribitol bond and the type 6B had a rhamnopyranosyl-(1 --> 4)-d-ribitol bond. Quantitative precipitation and absorption analyses with rabbit hyperimmune antisera induced by simultaneous injection with type 6A and type 6B organisms revealed extensive cross-reactions between the two group 6 polysaccharides. There was less, although still quite extensive, cross-reactivity between the two group 6 polysaccharides examined with antisera from rabbits injected with only one of the group 6 pneumococci. In a radioimmunoassay, using (14)C internally labeled type 6A or type 6B polysaccharide antigens, there was no difference in the serum antibody level to either type of volunteer injected with polyvalent pneumococcal vaccines containing type 6A or both type 6A and type 6B polysaccharides. These studies indicate that the structural similarity of the pneumococcal group 6 polysaccharides confers extensive cross-reactivity with hyperimmune typing antisera prepared with whole organisms or after injection of purified polysaccharides in adult volunteers. With our current polysaccharides, it appears that a polyvalent pneumococcal vaccine formulation that contains only type 6A will serve to induce the maximum amount of serum antibodies to both group 6 organisms.

Adult↗

Characterization of the cross-reaction between type 19F(19) and 19A(57) pneumococcal capsular polysaccharides: compositional analysis and immunological relation determined with rabbit typing antisera.

The immunological relation, physicochemical characteristics, and chemical composition of type 19F(19) and 19A(57) within the cross-reactive group 19 pneumococcal capsular polysaccharides were studied. By using rabbit hyperimmune diagnostic antisera in agglutination, immunodiffusion, quantitative precipitation, and absorption assays, extensive cross-antigenicity and cross-immunogenicity were demonstrable between the disease-associated types 19F(19) and 19A(57). Types 19B(58) and 19C(59), rarely associated with human disease, were extensively cross-reactive with each other but reacted weakly with types 19F(19) and 19A(57). Both types 19F(19) and 19A(57) polysaccharides contained trace amounts of protein and nucleic acid and had comparable molecular sizes as determined by gel filtration. Compositional analysis showed type 19F(19) to contain rhamnose, glucose, N-acetylmannosamine, and a phosphate ester. Type 19A(57) contained these four moieties, and in addition, contained fucose, galactose, and N-acetylglucosamine. Plans for using this information to evaluate current and proposed formulation of multivalent pneumococcal polysaccharide vaccines are discussed.

Antigens, Bacterial↗

Depletion of IgG in rabbit sera by absorption with some group A streptococci.

Streptococci group A, type M 1 or M 56 were capable to deplete IgG in normal rabbit sera during absorption by means of a surface Fc receptor. One absorption with 8.0 mg (dry weight) M 1 streptococci or two absorptions with 71 mg M 56 streptococci removed all IgG in 0.2 ml rabbit serum diluted 1:10 (containing 1.5 mg IgG/ml). Antibodies to egg albumin and antibodies to sheep red cells were not demonstrable after absorption of 0.2 ml serum diluted 1:10 with 16.0 mg M 1 streptococci. These results are discussed in relation to some reports on immunologic cross-reactions between streptococci and mammalian tissues.

Animals↗

Further studies of twitching Streptococcus sanguis isolated from the human throat. Isolation of strains with a new antigen.

alpha-haemolytic streptococci, classified as Streptococcus sanguis, with spreading growth due to twitching mobility were isolated from 41% of 121 swab cultures from the human pharynx. Sixty-five out of 70 isolates with spreading growth belonged to Lancefield's group H, while 5 isolates constituted a new serological entity. None of 159 non-spreading alpha-haemolytic streptococci isolated from the same cultures possessed either of these antigens. An examination of strains of types I, II and I/II described by Washburn et al., in the group H antisera employed in the present study indicated that type I and type I/II differ from one another in the degree of cross-reactivity with anti-type II serum. (The type II antigen was not demonstrated in any of the isolated strains). We support the opinion that type II should not be considered as S. sanguis.

Antigens, Bacterial↗

Correlation between twitching motility and possession of polar fimbriae in Acinetobacter calcoaceticus.

Negatively stained preparations of 16 strains of Acinetobacter calcoaceticus were examined in the electron microscope. Five of the strains did and 11 of the strains did not exhibit twitching motility. Two of the non-twitching strains were substrains of twitching wild-type strains. All twitching strains were found to possess fimbriae with a diameter of approximately 50 A. These fimbriae were shown to be of polar origin except in one strain where, for technical reasons, the origin could not be determined with certainty. Polar fimbriae could not be demonstrated in any of the strains that did not exhibit twitching motility. The demonstration of polar fimbriae was only regularly possible during the exponential growth phase, presumably because the fimbriae are shed by the bacteria during later growth phases. During the study, methods were developed for securing exponentially growing bacteria in concentrations suited for the preparation of negatively stained cells for electron microscopy. Peritrichously arranged fimbriae with a diameter of approximately 30 A were demonstrated in nearly all strains studied, especially on cells in late growth phases. The occurrence of this kind of fimbriae was therefore not correlated with the occurrence of twitching motility.

Acinetobacter↗

Twitching motility and possession of polar fimbriae in spreading Streptococcus sanguis isolates from the human throat.

A collection of 19 strains of alpha haemolytic streptococci, isolated from throat swabs and characterized by production of spreading zones around colonies on blood agar, was found to constitute a very homogeneous group with morphological, physiological and biochemical characters corresponding to those of streptococci of ser-group H, or Streptococcus sanguis, and they all appeared to possess the group H antigen. They all had a common agglutinogen and, in addition, heterogeneous agglutinogens. The spreading growth, which appears to be a common property of S. sanguis, was due to twitching motility, and the spreading cultures possessed polar fimbriae. tneither twitching motility nor the possession of polar fimbriae have been observed in gram-positive bacteria before.

Agglutination Tests↗

Examination of fimbriation of some gram-negative rods with and without twitching and gliding motility.

Negatively stained preparations of 30 different strains of gram-negative rods representing 20 different taxa were examined in the electron microscope. Thirteen of the strains studied exhibited twitching and six of the strains exhibited motility. Additionally, non-twitching substrains of two of the twitching strains and a non-gliding substrain of one of the gliding strains were examined. A variety of cultural media, preparations for negative straining and negative strains were used. It was found that all strains with twitching motility possessed fimbriae, the diameter of which was approximately 50 A in all but one strain; the fimbriae of this strain had a diameter of approximately 40 A. The fimbriae were judged to be of polar origin in all cases where the origin could be determined with certainty. On none of the strains without twitching motility could fimbriae be demonstrated. Only one of the six strains with gliding motility possessed fimbriae.

Alcaligenes↗