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J Henrichsen

Publications and source records attributed to J Henrichsen.

At least 73 records · Page 4Linked to original sources
PubMed1990

Covalent linkage between the capsular polysaccharide and the cell wall peptidoglycan of Streptococcus pneumoniae revealed by immunochemical methods.

The attachment of capsular polysaccharide to Streptococcus pneumoniae was examined using monoclonal and polyclonal antibodies. Among the strains examined, the capsular polysaccharide of types 2, 4, 6A, 6B, 7F, 8, 14, 19F and 23F was bound to the pneumococci whereas that of a type 3 strain was not. Sequential treatment with 2% SDS at 100 degrees C, pronase, and EDTA did not dissociate the capsular polysaccharide from the pneumococci. Treatment of the cells with mutanolysin, a muramidase that degrades the cell wall peptidoglycan of pneumococci and other streptococci, released both the capsular and the cell wall C-polysaccharide (C-Ps). Type 6A capsular polysaccharide released from cell walls by mutanolysin treatment, was fractionated by high performance liquid chromatography and examined by immunoelectrophoresis. It was found to be bound to both the C-Ps and the peptidoglycan. The bond between the capsular polysaccharide and the peptidoglycan has not yet been identified but is probably covalent, as the two components could not be dissociated after boiling in SDS. Based on our studies with type 6A, we propose that capsular polysaccharide and C-Ps of the pneumococcus are linked to the peptidoglycan at different sites and, thereby, indirectly to each other. Studies in mice showed that the peptidoglycan enhanced the serum antibody response to C-Ps but not to type 6A polysaccharide.

Amino Acids↗
PubMed1990

Pneumococcal revaccination of splenectomized children.

Forty-three Danish splenectomized children received a single subcutaneous dose of a 14-valent pneumococcal vaccine (Pneumovax 23; Merck). Blood samples were taken before, 4 weeks after and 5 years after vaccination. Total pneumococcal antibody concentrations as well as antibodies against each of the 14 pneumococcal capsular polysaccharide antigens were measured by the enzyme-linked immunosorbent assay method. Depending on the pneumococcal antibody status 5 years after primary vaccination, the children were either revaccinated with a new 23-valent pneumococcal vaccine or scheduled for reexamination later. The antibody concentrations found 5 years after vaccination showed a strong correlation with the prevaccination antibody concentrations. Revaccination of children with low antibody concentrations 5 years after primary vaccination is safe, is without significant side effects and leads to a satisfactory antibody response.

Adolescent↗
PubMed1990

Antibody persistence in splenectomized adults after pneumococcal vaccination.

16 splenectomized adults, all vaccinated with a 14-valent pneumococcal vaccine (Pneumovax) 1978-79 had their pneumococcal antibody concentrations measured before and up to 10 years after vaccination. The antibody concentrations after vaccination declined to 71% in 2 years and remained at this level during the 10-year study period. Further studies are needed to see whether this applies to all vaccinated splenectomized adults.

Antibodies, Bacterial↗
PubMed1990

Kits for the diagnosis of infectious mononucleosis compared with the Paul-Bunnell test.

We compared the results obtained with six different test kits for infectious mononucleosis with those obtained with the Paul-Bunnell test. The investigation was carried out in one laboratory using 149 selected pools of patient sera. Each pool was tested three times with the Paul-Bunnell test and once with each kit. The results obtained with the kits were grouped according to the titre found with the Paul-Bunnell test. The percentage of positive results within each group was calculated for each kit. The Paul-Bunnell titre, which would have classified 50% of the specimens as positive, was estimated for each kit and this was designated the 50% cut off value. In general, there was good agreement. However, false positive test results were found rather frequently with one kit (19%) and the 50% cut off values differed. One kit showed a 50% cut off value at about 8, another at about 16, and the rest at between 16 and 32. We suggest the introduction of improved internal quality control combined with external quality assessment.

Antibodies, Heterophile↗
PubMed1989

Local production of IgG to pneumococcal C-polysaccharide in upper airway secretions from children with recurrent acute otitis media.

Antibodies against C-polysaccharide (C-Ps), a common cell wall component of all pneumococci, may be of importance for the elimination of decaying pneumococci. By means of ELISA with phenylated C-Ps, anti-C-Ps IgG was measured in samples of plasma and upper airway secretions from otitis-prone children (OP), children with fewer episodes of recurrent acute otitis media (rAOM), and children with no previous history of AOM, but suffering from secretory otitis media (SOM). All children were free from acute illness at the time of sampling. No statistically significant differences of anti-C-Ps IgG in plasma or in nasopharyngeal secretions (NPS) were found between any of the groups. Based on calculations of the correlation between levels of anti-C-Ps IgG in plasma and NPS, and of the transudation ratios of anti-C-Ps IgG, total IgG, and albumin from plasma to NPS, we suggest that a significant amount of the anti-C-Ps IgG in NPS must be locally produced. The additional finding that OP children had significantly higher levels of anti-C-Ps IgG in their middle ear effusions (MEE) than SOM children points in the same direction. Anti-C-Ps IgA and IgM were detected in very low concentrations in plasma and secretion samples.

Acute Disease↗
PubMed1989

Etiology of community-acquired pneumonia in children based on antibody responses to bacterial and viral antigens.

The serologic responses to bacterial and viral antigens were determined in paired serum samples from 336 children, ages 1 month to 15 years, with roentgenographically verified community-acquired pneumonia. Significant increases in antibodies against one agent were found in 40% and against two or more agents in 8% of the children. There were significant increases in antibodies against respiratory syncytial virus in 20%, viruses of the influenza-parainfluenza group in 6% and adenovirus in 3%. A serologic response to one or more of the pneumococcal antigens used (type-specific capsular polysaccharide, C-polysaccharide and pneumolysin) was demonstrated in 13% of the patients. Ten percent of the children had significant increases in antibodies against Mycoplasma pneumoniae. Only three patients had increases against Haemophilus influenzae type b and one each against Legionella pneumophila and Chlamydia. Respiratory syncytial virus was the predominant etiologic agent in young children whereas M. pneumoniae was more frequent in the older age group.

Adenoviruses, Human↗
PubMed1989

Antibody response to pneumococcal vaccine in patients with early stage Hodgkin's disease.

Antibody response to pneumococcal vaccination was studied in 76 patients with Hodgkin's disease (HD) before, during and at different time intervals after cessation of therapy. All patients were in pathological stage I and II following explorative laparatomy with splenectomy. The increase in antibody response was compared to the findings in 12 healthy volunteers with the aim of establishing the optimal time for vaccination. Serum antibodies against 6 of the pneumococcal polysaccharide antigens (types 1, 4, 7F, 14, 18C and 23F) contained in the vaccine were determined by an ELISA. Antibody response to pneumococcal type antigens was similar in healthy adults and in patients with early stage HD before therapy. After treatment, postvaccination antibody response became negligible. Even up to 7 years after cessation of therapy patients were not able to raise a significant antibody response.

Adolescent↗
PubMed1989

Description of 14 new capsular types of Streptococcus suis.

Fourteen new capsular types of Streptococcus suis (types 9 to 22) are described. All reference strains are morphologically and biochemically similar to types previously described. Reference strain types 9 to 13, 15, 16, and 22 were isolated from diseased pigs, whereas types 17 to 19 and 21 came from clinically healthy pigs; type 14 was isolated from a human case of meningitis, and type 20 was isolated from a diseased calf. The group T streptococcus of de Moor has been included in the typing system as type 15. Two-way cross-reactions between types 6 and 16 and a one-way cross-reaction between types 2 and 22 have been demonstrated. In addition, several cross-reactions probably not due to capsular material were detected among different types by using the coagglutination test. This test should not be used alone; weak or multiple positive reactions must be confirmed by the capsular reaction test or the capillary precipitation test.

Agglutination Tests↗
PubMed1989

Enhanced IgG1 and IgG3 responses to pneumococcal polysaccharides in isolated IgA deficiency.

Serum IgG subclass-specific antibody concentrations to pneumococcal polysaccharides (PnPs) 1 and 14 were measured in 13 adult patients with isolated IgA deficiency and nine healthy adults immediately before and 4 weeks following immunization with polyvalent pneumococcal vaccine. Samples were analysed by enzyme immunoassay using pooled human serum as a reference preparation. A significant rise in median post-immunization antibody concentrations to PnPs14 was seen for all IgG subclasses, for IgA-deficient patients and for controls. For PnPs1, post-immunization IgG2 and IgG4 antibody concentrations rose significantly in the patient group, and IgG4 antibody concentrations rose significantly in the controls. The median IgG1 and IgG3 antibody concentrations to PnPs1 were significantly higher pre- and post-immunization in IgA-deficient individuals in comparison with controls, as were post-immunization IgG3 antibody concentrations to PnPs14. This enhancement of IgG1 and IgG3 antibody responses to pneumococcal polysaccharide antigens in IgA-deficient patients suggests an alteration in regulation of the normal switching processes in the generation of subclass and isotype diversity or could possibly be due to alteration in the affinity of subclass specific antibody.

Adult↗
PubMed1988

Structural studies of the capsular polysaccharide from Streptococcus pneumoniae type 18F.

The structure of the capsular polysaccharide elaborated by Streptococcus pneumoniae type 18F (S18F) has been investigated by using n.m.r. spectroscopy, methylation analysis, and characterisation of oligosaccharides obtained on partial hydrolysis. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol phosphate moiety has not been determined, but is assumed to be D-glycerol 1-phosphate (sn-glycerol 3-phosphate). The location of an O-acetyl group at O-6 of the terminal alpha-D-glucopyranosyl groups is tentative only.

Carbohydrate Conformation↗
PubMed1988

Structural studies of the capsular polysaccharide from Streptococcus pneumoniae type 18A.

The structure of the capsular polysaccharide (S18A) elaborated by Streptococcus pneumoniae type 18A has been investigated by using methylation analysis and n.m.r. spectroscopy. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol 1-phosphate moiety has not been determined but is assumed to be D from biosynthesis considerations. The structure of S18A is, as expected, closely similar to those determined for S18F and S18C.

Carbohydrate Conformation↗
PubMed1988

Incidence and diagnosis of acute rheumatic fever in Denmark, 1980 and 1983. A retrospective analysis of the fulfillment of the revised Jones criteria in hospitalized patients.

A review of 1547 official hospital record summaries concerning discharges during the period 1980 through 1983 of patients whose diagnoses had been coded as acute rheumatic fever revealed that in only 61% of the cases had this illness been diagnosed or suspected. A substantial proportion of the remaining patients had had acute non-rheumatic pericarditis diagnosed. The medical records were analyzed for 141 patients diagnosed in 1980 or 1983 by hospital departments as having acute rheumatic fever with regard to the revised Jones criteria. They were fulfilled in 47 patients, 23 of whom were considered unlikely cases of rheumatic fever. Eight patients were considered possible cases, although they did not fulfill the revised Jones criteria. The current annual incidence of acute rheumatic fever was estimated to be at most 0.3 per 100,000 inhabitants.

Acute Disease↗
PubMed1988

Ultrastructural localization of capsules, cell wall polysaccharide, cell wall proteins, and F antigen in pneumococci.

The localization of pneumococcal capsular and cell wall antigens was examined by immunoelectron microscopy. C polysaccharide (C-Ps), a common component of all pneumococci, was uniformly distributed on both the inside and outside of the cell walls. The thickness of the C-Ps varied with the strain. Encapsulated strains were covered by varied amounts of capsular polysaccharide concealing the C-Ps of the bacteria so as to render it inaccessible to anti-C-Ps antibodies. In addition to C-Ps, protein antigens were demonstrable on the surface of nonencapsulated pneumococci. The proteins were not masked by the C-Ps layer. An extra layer on the cell walls was conspicuous on electron micrographs of both rough and encapsulated pneumococci. The nature of this extra layer has not been disclosed. F antigen, another common antigen of pneumococci, was uniformly distributed on the surface of the plasma membranes. During the course of the experimental work a reproducible method of gold labeling immunoglobulins was developed.

Antibody Specificity↗