Humoral reaction to Bordetella pertussis antigens: pertussis toxin, filamentous hemagglutinin and lipopolysaccharide in children with clinical symptoms of whooping cough. II. Occurence and level of B. pertussis antigens in children with suspected whooping cough

The aim of this study was to determine and evaluate IgG, IgM and IgA levels to pertussis toxin (PT), filamentous hemagglutinin (FHA) and endotoxin (LPS) of B. pertussis in children with clinical symptoms of whooping cough. The serum samples obtained from 265 children (age range: 2 months-16 years) suspected of pertussis were examined by indirect haemagglutination (IH) and ELISA tests. Higher antibody level was most frequently observed in IgA class to PT, FHA and LPS in 45.3%, 35.1% and 66% of pertussis patients sera respectively. The least positive results were obtained in IgM class to PT and FHA (in 9.8% and 2.6% of children sera respectively) but in the case of LPS applied as the antigen in ELISA, higher IgM level was determined in 46.8% of pertussis patients sera. The four times increase of antibody level to LPS determined by IH was observed in 86.7% of children suspected of pertussis. Humoral response to B. pertussis infection is mainly connected with higher IgA level to PT, FHA, LPS and IgM to LPS in children with clinical symptoms of whooping cough.     

Serological diagnosis of Campylobacter jejuni infections

Antibody level to Campylobacter in 28 sera of patients of whom Campylobacter infection was confirmed by germ isolation from feces was tested. The investigation was performed using passive haemagglutination technique and as antigens heated and acid glycine extraction prepared from homologous and reference strains. For the method used the heated antigen proved to be superior. Out of 28 tested patients of whom 92.8% were children, 8 sera were positive, 9 doubtful and 9, derived mainly from neonates (0-14 month of age), were negative.     

Comparative methods of detecting HbsAg in chronic glomerulonephritis patients in Nigeria

Abstract A comparative evaluation of the enzyme-linked immunosorbent assay (Elisa), passive haemagglutination (PHA) and counterimmunoelectrophoresis (CIE) methods were carried out. Approx. 6% of control samples were positive with the Elisa assay, while the values for Behring Institute (BI) passive haemagglutination, Wellcome Research Laboratory (WRL) passive haemagglutination and CIE were 2.7%, 2.2% and 3.3%, respectively. The above data contrast with values of 21.3%, 10.6, 10.3 and 12.3 obtained in sera from chronic glomerulonephritis patients.
Our observation suggests that HbsAg may be associated with chronic glomerulonephritis.     

Comparison of enzyme-linked immunosorbent assay, electron microscopy, and reversed passive haemagglutination for detection of human rotavirus in stool specimens

An enzyme-linked immunosorbent assay (ELISA) using microplates as solid phase, rabbit antiserum against human rotavirus Wa strain as catching antibody, and the same reagent labeled with beta-D-galactosidase as conjugate, has been developed for detection of human rotavirus antigen(s) in stool specimens from patients with acute gastroenteritis. The limit of detection of purified human rotavirus by ELISA was 15.6 ng/ml (1.56 ng/well) of viral protein. The sensitivities of ELISA, electron microscopy, and the reversed passive haemagglutination method (ROTA-CELL) were compared. ELISA was more sensitive than electron microscopy and the reversed passive haemagglutination method. The ELISA blocking assay was useful for detection of an antibody response to human rotavirus in paired sera from children in two institutions during outbreaks of rotavirus gastroenteritis.     

Reliability of results evaluation for the passive hemagglutination test in pertussis obtained from WSSE laboratories

This study was undertaken for assessing of the reliability of the passive haemagglutination test with B. pertussis endotoxin in 18 laboratories of the Sanitary Epidemiological Stations. Each laboratory determined the level of pertussis antibodies in three serum samples twice, at interval of two weeks. The correct results were obtained in 7 laboratories (38.9%). The results of pertussis antibodies determination in only one or two samples were differed more than twice from correct in 5 additional laboratories; in this way the test was carried out satisfactorily in 12 laboratories (66.7%). Reproducibility of the results was good in 12 laboratories (66.7%). The study showed the necessity of repeated interlaboratory controls and periodic training of laboratory workers for raising of the quality and reliability of serological investigations for pertussis.     

Immunochemical and biological studies of antigens isolated from a strain of Bacteroides fragilis

Phenol/water-extracted lipopolysaccharide and a fraction HM, extracted with acetate buffer pH 2.0, from Bacteroides fragilis strain 62/73 are antigenically different as shown by immunodiffusion, passive haemagglutination, haemagglutination inhibition and preliminary chemical investigations. Biological activity, assessed with the local Shwartzmann reaction, was demonstrated for the lipopolysaccharide whereas antigen HM was almost inactive in this test. HM is immunogenic in rabbits. Antibodies against HM were detected in seven out of ten sera of healthy humans.     

Prevalence in England of Antibody to Human Polyomavirus (B.K.)

Over 500 human sera were tested by complement fixation and haemagglutination inhibition tests for antibody to the human polyomavirus (B.K.). Both tests showed that antibody to this virus was very common in the population and began to be acquired after the age of 1 year. No clinical illness has so far been associated with the development of this antibody in a series of paired sera from children.     

Microtissue Culture Test for the Titration of Low Concentrations of Diphtheria Antitoxin in Minimal Amounts of Human Sera

A microtissue culture method for the assay of low concentrations of diphtheria antitoxin in human sera has been developed, using a monkey kidney cell (VERO) culture technique. Results obtained with sera from nonvaccinated children and with immune sera from children vaccinated with three and four injections of diphtheria pertussis tetanus vaccine were in agreement with antitoxin levels considered necessary to denote immunity to diphtheria. The use of microplates and organic buffer for culturing the animal cells improved the stability of the tissue culture system. The described method is sensitive, economical, and applicable for the titration of antitoxin in human sera particularly from infants and children from whom a minimum amount of serum is available.     

Possible serodiagnosis of pertussis infection by an immunoenzyme method

The sera of children and adults with a history of pertussis, as well as the sera of children immunized in three injections, have been studied in the enzyme immunoassay. The levels of antibodies to Bordetella pertussis protein and lipopolysaccharide, and to disintegrated B. pertussis cells have been determined; a serum titer of 1:1,600 and higher is considered as a criterion for the serological diagnosis of pertussis.     

Evaluation of three serological tests for the detection of human plague in northeast Brazil.

The passive haemagglutination (PHA) test, enzyme-linked immunosorbent assay (ELISA) and the dot enzyme-immunosorbent assay (DOT-ELISA) were used to detect the levels of IgG antibodies against the Fraction 1 (F1) antigen of Yersinia pestis in sera of plague-infected patients from Northeast Brazil. Twenty three selected PHA-positive sera of subjects with bacteriological confirmation of plague were also positive in the DOT-ELISA but only 19 were detected by the conventional ELISA technique. Another group of 186 serum samples from subjects diagnosed as plague-infected by clinical and epidemiological parameters, but PHA-negative, were screened with DOT-ELISA and 11 gave positive results. The specificity of the assays on the serological detection of plague was confirmed in inhibition tests using purified F1 antigen. These results suggest that DOT-ELISA can be an useful, simple and more sensitive alternative for the serodiagnosis of plague in Northeast Brazil.     

Typhoid fever survey in two localities in Vietnam

As a part of multipurpose health survey of the population in Vietnam the antibodies against S. typhi were determined by the micromethod using haemagglutination test (O-antigen 9, 12) and agglutination test using standard H-diagnostic antigen (d). Totally 292 sera were examined, 139 from Duyen Thai village and 154 from Mai Chau. The data on vaccination against typhoid fever are recorded only in 102 persons. The positivity on Vi antibodies is very high--70% in Duyen Thai and 47% in Mai Chau. This finding is significant according to the high titres in the carriers of S. typhi. The titres of all antibodies are lower in Mai Chau area situated in mountains then in crowded lowlands of Duen Thai. The level of antibodies is decreasing with age. The frequency distribution of antibodies by age proves endemicity of the disease in area, where a large part of population is infected already before reaching 20 years of age. The effectivities of vaccination is discussed.     

Determination of antibodies to diphtheria and tetanus toxoid by latex agglutination technique

A micromethod of latex agglutination was worked out for determination of antibodies to diphtheria and tetanus toxoids. It is suitable for pediatrics since a minimum amount of serum (0.05 ml.) is required, which can be used without being inactivated or absorbed. Particles of polystyrene latex of Czechoslovak production were used as antigen carriers thus enabling better standardization of the technique. The particles are well defined both in physical and chemical terms and replace red blood cells in passive hemagglutination. The method was compared with passive hemagglutination in a dynamic study of children inoculated at monthly intervals with the trivalent vaccine Alditepera.     

Reliability of the cut-off value in the routine serodiagnosis of pertussis performed by the commercial ELISA assays

In clinical practise, serodiagnosis of pertussis is mostly based on single-sample serology using a single cut-off. The reliability of the cut-off value has the crucial influence for the sensitivity and specificity of the used tests. In this context we compared the value of cut-off used in two commercial ELISA kits (NovaLisa Bordetella pertussis-NovaTec and ELISA Bordetella pertussis ELISA-Virotech) with cut-off settled by calculation the IgA and IgG results from the 60 healthy Polish children and 100 blood donors (arithmetic mean plus 2 or 3 standard deviations). Our study indicates that IgA cutoff used in NovaTec ELISA, in contrary to Virotech ELISA, correspond better to the level x+3SD calculated in children sera and x+2SD calculated in adult blood donors sera. The value of IgG cut-off used in Virotech ELISA was lower about 20% and 30% from the cut-off settled by us respectively on the level ofx+2SD and x+3SD in all tested sera. The most inadequate value had the IgG cut-offused in NovaTec ELISA, which was over three times lower than mean cut-off value settled by calculation results from the sera obtained from healthy children and blood donors. This low cut-off value established by the NovaTec was the reason that 23.3% of healthy children and 55.0% of blood donors have the IgG antibodies on the diagnostic significant level. Our data suggest that commercial ELISAs need further improvement and standardization.     

Composition of immunoglobulins in brucellosis patients using DEAE-cellulose column chromatography.

The composition of immunoglobulins in patients with brucellosis was studied. The method of ion-exchange chromatography on DEAE-cellulose columns was used to define more precisely the physico-chemical character of cysteine-resistant antibodies. The study of IgM, IgA and IgG fractions obtained from the patients sera showed the IgG fraction to possess the greatest serological activity in the agglutination reaction, in the passive haemagglutination reaction and in Coomb's test. Specific antibodies in the remaining 2 fractions (IgA and IgM) were found only in single patients in low titres, mainly in Coomb's test (incomplete antibodies). The study of IgM, IgA and IgG serum fractions before and after cysteine treatment revealed cysteine-resistant antibodies to be usually IgG globulins. The presence of specific IgG antibodies in the sera of patients was found to correlate with active clinical manifestations of brucellosis.     

Immunological study of antisera to to artificial O-antigen of Pseudomonas aeruginosa

O-sera were obtained by immunizing rabbits with artificial antigens: polysaccharide extracted from the lipopolysaccharide of P. aeruginosa (strain No. 868; 03a, 3d, 3e), or the high-molecular-weight or low-molecular-weight fraction of this polysaccharide, complexed with a natural protein (human IgG or rabbit globulin). The antisera to these antigenic complexes were highly O-specific. Antisera to the complexes of polysaccharide-protein and high-molecular-weight fraction-protein were more active in the passive haemagglutination reaction, slide agglutination test and immunodiffusion test in agar gel than was antiserum to the low-molecular-weight fraction-protein complex. The artificial antigens prepared and employed in the study are apt to be used for the preparation of monospecific immune sera.     

Anti-immunoglobulins in multiple myeloma and benign monoclonal hyperglobulinemia]

Sera from 50 healthy adults, from 21 patients with multiple myeloma (MM) and from 11 patients with benign monoclonal hyperglobulinaemia (BMH) and from 28 patients with sarcoidosis were examined for the presence of anti-IgG-activity by passive haemagglutination technique. 62% of healthy adults (titre less than 2) and all of the sera from patients with MM and BMH (titres 32-512) as well as 42% of the sera from sarcoidosis patients were found to be anti-IgG positive. The anti-IgG positive sera showed also anti-(Fab)2-activity (with the exeption of 2 sera from sarcoidosis patients). No significant differences could be found between anti-Ig activity in sera from MM patients with BMH. There was also seen no correlation of anti-Ig with the clinical course of the disease. After column chromatography we could detect the partially simultaneous presence of anti-Ig with anti-Fc-specificity (MW ca. 900,000) and with (Fab)2-specificity (MW 150,000 or less than 90,000). Antibody dependent cytotoxicity (using melanoma cell lines as targets) was significantly inhibited by the isolated anti-Ig-fractions with low molecular sizes (MW less than 90,000). From these results it seems possible that anti-immunoglobulins may play a role in the clinical course of the disease.     

Changes in collagen metabolism--another look at osteoarthrosis

Collagen types I and III were isolated from osteoarthrotic cartilage. Immunofluorescence study has shown that these two collagen types are present in the deep layers of cartilage. Additional staining for fibronectin revealed the presence of the cell-adhesive protein in osteoarthrotic cartilage. Neither collagen type I and type III nor fibronectin were found in control cartilage. A passive haemagglutination assay determined anticollagen antibodies (against types I, II and III) in sera of some osteoarthrotic patients.     

Passive protection of mice with the 19 S and 7 S fractions of anti-pertussis sera in experiment.

Protective activity of anti-persussis rabbit and mouse sera and 19 S and 7 S fractions obtained from these sera was investigated in the test of passive protection of mice on a model of pertussis meningoencephalitis. The method of simultaneous intracerebral administration of the serum or fraction with live culture of a virulent B. pertussis strain was used. Hyperimmune rabbit serum containing mercaptoethanol-resistant agglutinins in a high titre was found to have the most pronounced protective effect. Serum of mice, collected 14 days after single immunization of the animals, did not show any protective properties. A small amount of protective activity was observed in the serum collected on the 30th day after a single administration of the vaccine. A sharp increase in the protective activity of the serum was observed after double immunization of mice. Correlation was found between the increase in the titre of agglutinins (in particular of 7 S antibodies) and the protective activity of the serum. Protective properties of 19 S and 7 S fractions isolated from immune rabbit and mouse sera by the method of gel filtration were investigated. Both fractions were found to possess protective properties, but fraction 7 S was more active than fraction 19 S.     

Enzyme-linked immunosorbent assay (ELISA) for IgM, IgG and IgA class antibodies against Candida albicans antigens: development and comparison with other methods

An extract of Candida albicans was used as an antigen on microtitre plates in the enzyme-linked immunosorbent assay (ELISA) to measure IgM, IgG and IgA class antibodies in the sera of hospitalized patients. It was found that of these patient sera that reacted positively in Ouchterlony immunodiffusion (ID) when undiluted, 58% were also positive in the ELISA against the same antigen preparation. However, all the sera with an ID titre of 1:2 or higher were ELISA-positive, demonstrating especially IgG and IgA. Of the sera positive by counterimmunoelectrophoresis against somatic and metabolic antigens of C. albicans, 86% were positive by ELISA. Reactions in precipitin-negative sera, if they occurred, usually demonstrated IgM or IgA. The sera with high passive haemagglutination or indirect immunofluorescence titres against surface antigens of C. albicans were positive in the IgG and IgA assays, while approximately one third were positive in the IgM assay.     

Rapid assay for antibodies to Varicella-Zoster virus (VZV) using a VZV-HEM preparation

A freeze-dried, formalized-erythrocytes-bound VZV antigen for indirect haemagglutination, VZV-HEM, was prepared. It was used to test serologically 46 children, all of them patients of Prague paediatric clinics, with a known history of chickenpox. For comparison, the same sera were tested by the indirect haemagglutination reaction with freshly prepared VZV antigen and by ELISA. All three serological tests gave congruent results in 97.8% of cases. The advantages of the VZV-HEM assay are results obtainable within 2 hours of serum dilution and simplicity. The assay is especially suitable for emergency testing the immunity of persons at risk.