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PubMed1969

Serological properties of lipopolysaccharide from oral stains of Bacteroides melaninogenicus.

Lipopolysaccharide (LPS) extracted with phenol-water from four oral strains of Bacteroides melaninogenicus was found to be serologically active in precipitation and complement fixation tests and sensitized sheep erythrocytes to agglutination. Except for the capacity to inhibit indirect hemagglutination, the serological activity was destroyed by oxidation with periodate. The isolated LPS was antigenic in rabbits, giving rise to low- and high-molecular-weight antibodies. Cross-reactivity experiments revealed the presence in LPS of both type-specific and group-reactive antigenic determinants.

Agglutination Tests↗
PubMed1978

The diagnostic efficiency of some serological tests for bovine brucellosis.

Results obtained from 1887 sera using three serological tests for bovine brucellosis were compared with a serological classification of sera described as the 'probable infection status'. Sera showing apparent false positive and apparent false negative reactions were identified, and were subjected to supplementary testing as appropriate. The serum agglutination test (SAT) gave 35% apparent false negative reactions and 5% apparent false positives. The complement fixation test (CFT) gave 12% apparent false negative reactions using warm fixation (CFTW) and at least 5% using cold fixation (CFTC). The routine diagnostic system used in Victoria, in which the CFTW is supplemented by the CFTC and the SAT, gave 9% apparent false negative reactions and 2% apparent false positive reactions. The radioimmunoassay gave 1% or 6% apparent false negative reactions, depending on the minimum diagnostic value used. Atypical reactions in the CFT sometimes caused difficulties in diagnosis.

Agglutination Tests↗
PubMed1988

Further evidence that bovine IgM does not fix guinea pig complement.

In a study of sera from cattle vaccinated with 3 X 10(10) cfu of Brucella abortus strain 19, it was found that IgG1 antibody measured by an indirect ELISA was the only isotype to correlate with standard complement fixing antibody titers using heated serum samples and guinea pig serum as a source of complement. A supplement of normal unheated bovine serum resulted in IgM fixing guinea pig complement, giving data similar to those obtained with unheated serum in the complement fixation test.

Animals↗
PubMed1975

Heterologous reactions involving parasites, blood group antibodies and tissue components.

The sera of many patients with malaria and filariasis, and also anti-A and B blood group sera, were found to react by immunofluorescence with the somatic musculature of nematodes, especially Ascaris, and human and rat muscle, especially the skeletal type. These reactions were attributed to a polysaccharide related to AB substance in adult nematodes and to raised AB antibodies in malaria. Similar heterologous reactions were found to involve the integument of schistosome adult worms and the microfilariae of Loa loa, which were attributed to the incorporation of host AB blood group substances into the parasite. Other parasites and sera gave mainly negative results. These heterologous reactions constitute a potential hazard in immunofluorescence tests, against which skeletal muscle provides a control. The antibodies concerned were not operative in complement fixation tests, but there was a relationship to anti-complementary activity which suggested the transient presence of a circulating antigen.

ABO Blood-Group System↗
PubMed1983

Counterimmunoelectrophoresis (immunoelectroosmosis) and serum electrophoretic pattern in serologic diagnosis of canine blastomycosis.

Counterimmunoelectrophoresis (CIEP) with blastomyces and histoplasma antigens was used in a serologic study of 181 dogs clinically suspected of having blastomycosis and of 8 dogs with confirmed blastomycosis or histoplasmosis. Thirteen of the 181 dogs, positive by CIEP, were euthanatized, and the diagnosis was confirmed by cultivation and/or microscopic detection of Blastomyces dermatitidis. Additional CIEP-positive dogs were confirmed by staining of aspirates collected in vivo. Radiographic support for the diagnosis was reported in 4 other dogs in which histoplasmosis was excluded by a negative CIEP with histoplasma antigen. The precipitating antibody may disappear during the course of the disease, as it did in 1 dog treated with amphotericin B, but not cured. This dog reverted from CIEP-positive to CIEP-negative within 17 months of treatment (with a weak reaction after 10 months of treatment). The CIEP-detectable antibody was present only in 1 dog without a confirmation by histopathologic findings or cultivation among 24 well-documented cases and 181 total tested sera. The CIEP was more sensitive and specific than was the gel-diffusion precipitin test, eliminated the problems of anticomplementarity that often affected the results of complement-fixation tests with canine sera, and served well in detecting dogs with blastomycosis. Electrophoretic pattern of sera from CIEP-positive dogs with blastomycosis showed a decrease in albumin and an increase in alpha 2- and often in beta- and gamma-globulins, with a substantial decrease of the albumin/globulin ratio.

Animals↗
PubMed1997

[Diagnostic test kit for detection of antibodies to syphilis agent].

A diagnostic enzyme immunoassay test kit is proposed for detecting anti-treponema antibodies in sera of syphilis patients, usable in two variants: on prefabricated polystyrene plates or by immunofiltration using a membrane filtration enzyme immunoassay kit. A peculiar feature of the test kit is the use of enzyme immunoassay conjugate based on monoclonal antibodies to light chains of human immunoglobulins, highly purified antigen from cultural T. pallidum, two substrates for detecting enzymatic activity. The efficacy of the test was confirmed on 163 patients' and control sera and compared with that of the complement fixation test, two modifications of immunofluorescent test, and micromodification of the precipitation test. The test proved to be highly sensitive, specific, and reproducible, and is recommended as a confirmation test for the diagnosis of syphilis.

Antibodies, Bacterial↗
PubMed1984

Seroepidemiology of Q fever in Nova Scotia and Prince Edward Island.

The prevalence of Coxiella burnetti infection (Q fever) was determined among Nova Scotia (N.S.) and Prince Edward Island (P.E.I.) blood donors by using the complement fixation and microimmunofluorescence (IF) test. The complement fixation and IF antibody tests measured antibody prevalence for the phase II or phase I and II antigens, respectively. Complement-fixing antibodies to phase II antigen were detected in 4.1% of 997 N.S. and 5.0% of 219 P.E.I. blood donors. Anti-phase II antibodies were detected by microimmunofluorescence in 11.8 and 14.6% of the blood donors in the two provinces, respectively. Anti-phase I antibodies were detected among 2.8% of the N.S. blood donors and 6.3% of the P.E.I. blood donors. Comparison of rates of anti-phase II IF by counties in N.S. revealed that there was at least one county where infection by C. burnetti is hyperendemic. Rates of antibody prevalence were similar in all three areas of P.E.I. examined. We conclude that "Q fever" is endemic in N.S. and P.E.I. and that the microimmunofluorescence test is more suitable than the complement fixation test for seroepidemiologic studies.

Adolescent↗
PubMed1990

The persistence of serological reactions following heifer vaccination with Brucella abortus strain 19 on brucellosis-free farms.

Of 392 heifers vaccinated between 4 and 9.5 months of age and tested at 22 months or older, 3 (0.77%) had titres in the complement fixation test of between 30 and 98 international units per millilitre. The results confirm that persistent serological reactions can be a problem even in brucellosis-free herds. To reduce the incidence of these problem reactors, it is suggested that: in clean herds the age of inoculation be reduced to 3 months of age; the age at first testing be delayed as long as possible, but be done before the heifers are 4 months pregnant, c) consideration be given to reducing the vaccine dose for all heifers from the present 4 to 12 x 10(10) to between 3 x 10(8) and 3 x 10(9) and syringes used for strain 19 vaccination be exclusively reserved for this purpose to prevent the possibility of antigenic residues acting as a booster when used for other vaccinations.

Age Factors↗
PubMed1984

Prevalence of cytomegalovirus antibodies in Norwegian kidney-transplant recipients and their living donors. A comparative study of two different methods.

376 sera from Norwegian kidney-transplant recipients and their living, related donors, were tested for the presence of cytomegalovirus antibodies (CMV-ab) by the complement fixation test (CF), and for IgG CMV-ab by the enzyme-linked immuno-sorbent assay (ELISA). Whenever the results of the two methods differed, the sera were also tested by the indirect fluorescence antibody test (FAT). 325 of 376 sera showed corresponding results, giving a concordance of 86 per cent between CF and ELISA, ELISA being the more sensitive of the two, with a sensitivity in the same range as FAT, and high specificity with only 0.3 per cent false positive results. The prevalence of CMV-ab in Norwegian kidney-transplant recipients and their living, related donors, differed very little. The overall CMV-ab seropositivity was 76 per cent. The prevalence increased from 50 per cent at the age of 20 years, to 80 per cent at 30 years and 90 to 100 per cent from 60 years of age.

Adult↗
PubMed1986

[Detection of antibodies against TORCH agents during pregnancy].

The antibody levels against TORCH agents in sera samples from pregnant women who admitted to Hacettepe Medical Faculty Hospital Obstetrics and Gynecology Department were tested. The measurements of IgG antibodies by ELISA against Toxoplasma gondii in 301 sera was given 47.8% sero-positivity. Rubella ELISA-IgG test performed for 226 sera given 89.8% seropositive value. 128 sera were also tested for the presence of Cytomegalovirus (CMV) IgG antibodies and 87.5% seropositivity is found. Complement fixation test is employed for the detection of Herpes simplex virus type 1 (HSV) antibodies in 65 sera samples and 87.5% of sera tested were given positive result in various titers. These results are discussed in terms of seronegativity of this population, sensitivity of ELISA test and the distribution of antibody levels.

Adolescent↗
PubMed1957

Staining toxoplasma gondii with fluorescein-labelled antibody. II. A new serologic test for antibodies to Toxoplasma based upon inhibition of specific staining.

A new serologic test for antibodies to Toxoplasma is described, which is based upon inhibition of specific staining with fluorescent antibody. In performing the test, a mixture of the test serum and known fluorescein-labelled antiserum is added to a dried smear of toxoplasms for 1 hour at 37 degrees C. The smear is then rinsed and examined with a fluorescence microscope. Reduction in the brightness of fluorescence, as compared to that of a negative control slide, indicates the presence of antibody in the test serum. A comparison of the results of this test with those of the methylene blue dye test showed a strong parallelism between the two sets of results. On the other hand, the complement-fixation test for toxoplasmosis did not yield nearly as many positives as the inhibition test. The specificity of the new test was studied by comparing it with dye test results and clinical histories in human patients, and by testing a group of animals immunized with a variety of non-Toxoplasma antigens. No evidence of cross-reactions was obtained in the latter series. Some advantages and disadvantages of the inhibition test are discussed.

Animals↗
PubMed1991

Ten and a half years seroepidemiology of Mycoplasma pneumoniae infection in Denmark.

The study was based on a computerized card index of 9161 patients who had at least one positive blood specimen in the Mycoplasma pneumoniae complement fixation test. A total of 12,562 specimens from these patients had been sent to Statens Seruminstitut from hospitals and general practitioners during a 10.5-year period. The period encompassed a previously described endemic period in a 30-year study of the epidemiological pattern of M. pneumoniae infection in Denmark. The serological data presented support the hypothesis advanced here that a more than sixfold increase of children in day care might have contributed to a change in the epidemiological pattern. The correlation between age and level of specific antibodies, as well as persistence of seropositivity, were also investigated.

Adolescent↗
PubMed1972

The serum and conjunctival antibody response to trachoma in Gambian children.

Ninety-nine young Gambian children were studied for 61 weeks. About half of them had trachoma at the outset, and 80% of the remainder acquired the disease while under observation. IgG trachoma antibody in the serum and IgG and IgA antibodies in the conjunctival secretions (CS) were titrated by an indirect immunofluorescence method. In serum samples obtained in capillary tubes the mean titre was slightly higher than in samples collected on filter paper. Serum antibody at titres >/= 1/10 was invariably associated with a clinical diagnosis of trachoma; it increased both in frequency and titre as the disease progressed, and was present in about half of those with Tr II. In CS, IgG antibody was present less often and at lower titres than in serum, and IgA antibody was detected even less frequently. There was some evidence of correlation between the titres of IgG and IgA antibodies in CS, but none for a relationship between the titres of the antibodies in serum and those in CS. Antibodies were almost never present in the absence of conjunctival follicles, but their titres were unrelated to the degree of follicular hyperplasia; there was no obvious relationship between the serological findings and corneal lesions. In children diagnosed clinically as trachoma, serum antibody was present in almost all those with conjunctival inclusions, and in a proportion of inclusion-negative subjects; the mean titre was much higher in the inclusion-positive group.These findings do not settle whether CS antibodies are made locally, or are derived partly or wholly from the blood. They suggest that the indirect immunofluorescence test may be a useful diagnostic aid in trachoma, particularly in view of the rarity of false positive reactions; but there is at present little to choose between it and complement-fixation tests in terms of sensitivity.

Antibody Formation↗
PubMed2002

Investigations of outbreaks of contagious caprine pleuropneumonia in Eritrea.

Mycoplasmas were isolated from freeze-dried lung samples from goats from the western lowlands of Eritea suspected of being affected by contagious caprine pleuropneumonia. The goats belonged to two herds in which mortality and morbidity rates were high. Mycoplasma capricolum subsp. capripneumoniae was identified in most samples by the polymerase chain reaction and by conventional serological tests. The latex agglutination test detected more positive serum samples in both herds than did the complement fixation test. Following cloning, the isolates of M. capricolum subsp. capripneumoniae were analysed biochemically and shown to be metabolically similar. They oxidized glucose, N-acetylglucosamine, pyruvate and L-lactate with high affinity and mannose, glucosamine and 2-oxobutyrate with low affinity; they were unable to utilize maltose, trehalose, fructose or ethanol. Major improvements were seen in the growth yield of the Eritrean strains with the addition of pyruvate to the medium. Thus, it may be that organic acids are important energy sources for these strains and may be used in addition to or in place of glucose. In contrast to most other strains of the M. mycoides cluster, the Eritrean strains produced large amounts of hydrogen peroxide during the oxidation of NADH by lysed cells. This characteristic had previously been reported for strain M. F38, the type strain of M. capricolum subsp. capripneumoniae, although strain F38 did not metabolize sugars. Hydrogen peroxide has long been considered a pathogenicity factor in mycoplasma infections. This is the first isolation of M. capricolum subsp. capripneumoniae from Eritrea.

Animals↗
PubMed1963

EFFECT OF ADJUVANTS ON ANTIBODY RESPONSE OF RABBITS INOCULATED WITH VENEZUELAN EQUINE ENCEPHALOMYELITIS VIRUS.

Shepel, Michael (U.S. Army Biological Laboratories, Fort Detrick, Frederick, Md.) and Maxwell R. Klugerman. Effect of adjuvants on antibody response of rabbits inoculated with Venezuelan equine encephalomyelitis virus. J. Bacteriol. 85:1150-1155. 1963.-Hemagglutination-inhibition, neutralization, and complement-fixation tests were performed on sera of rabbits inoculated with Venezuelan equine encephalomyelitis (VEE) virus in combination with Freund's adjuvants and in Hank's salt solution. This study indicated that the complete adjuvants (i.e., with mycobacteria) considerably increased the antibody response to VEE virus. Mycobacterium butyricum (M. smegmatis) appeared to be more effective than M. tuberculosis H37Ra. In the absence of mycobacteria, the response was much less pronounced. Paper electrophoretic studies of the antisera demonstrated a marked increase in gamma-globulin production, an increase in the beta-globulin, and an increase in total protein as the result of adding VEE virus to the complete adjuvants. A decrease in the albumin fraction appeared to be caused by the complete adjuvants rather than by the VEE virus itself. The incomplete adjuvant (without mycobacteria) plus virus contributed little, if any, stimulation toward the production of gamma-globulin, nor did it appear to affect the serum-albumin levels.

Animals↗
PubMed1987

Methodological aspects of a serodiagnostic Clostridium tumour test--experience with spontaneous canine tumours.

The paper describes the development of appropriate antigen and method combinations for the microbiological cancer test using the non-oncolysing strain Clostridium butyricum CNRZ 528 in dogs with spontaneous tumours. The diagnostic rod antibodies could be determined quantitatively by the complement fixation test if a short-time warm fixation and a long-time cold fixation procedure were combined in separate runs and if two different antigens, a rod corpuscular antigen and a rod surface antigen, were used. Since complement-fixing antibodies were not always detected in cases of malignant tumours, we additionally used the passive haemagglutination method after pre-absorbing the sera with cross-reacting clostridial antigens. The efficiency of the microbiological cancer test could not be substantially increased, however, by the method combination the reliability of the evaluation of low seropositive titres was improved.

Animals↗