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PubMed1979

Detection of arbovirus antibodies in avian sera by the complement fixation-inhibition test.

The complement fixation-inhibition (CFI) test was described for the detection of antibodies to arboviruses in bird sera. The CFI antibody present in bird sera inhibited the standard complement-fixation reaction of a reference complement-fixing antigen-antibody pair. Using reference antigens (St. Louis encephalitis, eastern equine encephalomyelitis, western equine encephalomyelitis, and yellow fever) prepared from infected mouse brains and reference antisera prepared in rabbits or horses, reproducible CFI antibody titers were obtained in artificially immunized chickens. Time-course studies on the CFI immune response in birds inoculated with live St. Louis encephalitis virus indicated that the CFI antibody was distinct from the antibody detected by the hemagglutination-inhibition test.

Animals↗
PubMed1960

Flocculation tests in hydatid disease.

A new serological technique of diagnosing human hydatid disease, employing polystyrene latex particles coated with hydatid cyst fluid, and a modified technique using bentonite particles are described. Comparison of the latex test with the complement-fixation test performed on 102 sera has shown a total agreement of 98% and an agreement of 93.1% in the positive specimens. The bentonite test and the complement-fixation test performed on 126 sera have shown a total agreement of 97.6% and an agreement of 90.1% in the positive specimens. Both flocculation tests are simpler to perform than the complement-fixation test. They are specific, and sensitivity closely parallels that of the complement-fixation test, with 6.9% and 6.1% of the positive specimens showing higher sensitivity in the latex and bentonite tests respectively. The bentonite test was less sensitive than the complement-fixation test in one case. None of the latex tests showed less sensitivity. The antibody active in the latex test has been demonstrated in a gamma globulin fraction of the antiserum. Some differences in the behaviour of flocculating and complement-fixing properties of sera are discussed.

Antibodies↗
PubMed1984

Evaluation of the enzyme-linked immunosorbent assay in the detection of cattle infected with Brucella abortus.

One group of 51 cattle was vaccinated with B. abortus S19 (S19) and a further 51 cattle were vaccinated with B. abortus S45/20 (S45/20). Forty-eight cattle (24 from each group) and a control group of 12 cattle were subsequently challenged with B. abortus S544. The enzyme-linked immunosorbent assay (ELISA) was used to detect specific IgG and IgM antibodies in these groups. All cattle vaccinated with S19 had high levels of IgG and IgM, but the S45/20 vaccine produced detectable antibody in only a few cattle. In those cattle where the challenge induced infection, the mean levels of IgG and IgM were much higher than those of the uninfected cattle in the same groups. When the isolation of B. abortus was compared at slaughter with the serological results, the ELISA, when used to detect specific IgG, was more sensitive but less specific than the serum agglutination test, complement fixation test and indirect haemolysis test, and more sensitive and more specific than the Rose Bengal test.

Animals↗
PubMed1996

The sensitizing effect of a Brucella abortus antigen in cattle after repeated intradermal inoculations.

An antigen prepared from a mucoid strain of B. abortus was repeatedly injected intradermally into cattle to determine whether it sensitizes cattle so that they test false positive with the skin delayed-type hypersensitivity (SDTH) test. Cattle (n = 14) that were experimentally inoculated. with microorganisms that serologically cross-react with B. abortus, and uninfected cattle (n = 15) were tested with the antigen 2 to 5 times over a period of 16 to 17 weeks. An increase in skinfold thickness of > or = 2.0 mm on the injection site was considered a reaction elicited by the antigen. The sera from the cattle were tested with the serum agglutination test, complement fixation test, and an enzyme-linked immunosorbent assay for antibodies against B. abortus. Results showed that none of the animals had an increase in skinfold thickness of > or = 2.0 mm on the injection site of the antigen, which is considered a positive reaction. However, cattle experimentally inoculated with microorganisms other than B. abortus tested seropositive for brucellosis after one SDHT test only. We conclude that the B. abortus antigen inoculated intradermally does not sensitize cattle after repeated inculations, and therefore does not interfere with the subsequent use of the SDTH test in the diagnosis of brucellosis.

Animals↗
PubMed2001

Experimental exposure of llamas (Lama glama) to Brucella abortus: humoral antibody response.

Positive antibody reactions to brucella were observed in the sera of four llamas receiving Brucella abortus Strain 19 subcutaneously at 2-3 weeks post-exposure (PE) using five of eight conventional brucella serologic tests and an ISU-ELISA. Positive brucella antibody reactions were detected in sera of four llamas exposed by intraocular instillation (IOI) of 1.02x10(8) (high dose) B. abortus Strain 2308 at 16-35 days PE using seven of eight serologic tests or an ISU-ELISA. Brucella antibody was also detected in sera of four llamas exposed by IOI of 9x10(5) (low dose) B. abortus using each of four agglutination tests, Complement Fixation test, PCFIA, the rivanol test and the ISU-ELISA at 16-35 days PE. Positive reactions were observed using the Card test, BAPA, SPT, STT, the rivanol test, the PCFIA, and the ISU-ELISA on sera collected on days 42-70 PE, except on one llama, given the low dose; that llama was negative on the PCFIA on day 42. Positive or suspicious reactions were not detected in sera of controls, receiving saline subcutaneously, using the routine tests, with the exception of the CFT. The B. abortus Strain 2308 was isolated from tissues of seven of eight llamas exposed to virulent B. abortus Strain 2308.

Animals↗
PubMed1997

Serological crossreactivity between Brucella abortus and Yersinia enterocolitica 0:9. III. Specificity of the in vitro antigen-specific gamma interferon test for bovine brucellosis diagnosis in experimentally Yersinia enterocolitica 0:9-infected cattle.

The course of immunological reaction in 10 Yersinia enterocolitica 0:9 experimentally-infected heifers was followed using the conventional brucellosis tests complement fixation test (CFT), serum agglutination test (SAT) and brucella card test (BCT), and a recently developed Brucella antigen-specific gamma interferon (IFN-gamma) test. Initially, the animals were exposed orally to 10(10) colony-forming units (CFU) of Y. enterocolitica 0:9. Four weeks later, they were inoculated intravenously with 10(8) CFU of Y. enterocolitica 0:9 cells. After oral inoculation, the response in the conventional brucellosis tests was minimal. Only after intravenous inoculation were CFT and SAT titres and BCT reactions comparable to natural, false positive brucellosis reactors. After oral exposure the Brucellergen-stimulated release of IFN-gamma peaked at values above the cut-off stimulation index of 2.5 in 80% of the heifers. After intravenous inoculation, stimulation indices above 2.5 were present in only 10% of the animals. Two B. abortus infected control cattle showed stimulation indices of 3.1 and 3.4, and a negative control animal exhibited a stimulation index of 1.0. These findings show, in contrast to a previous study, that the Brucellergen-specific IFN-gamma assay cannot be used as a specific and discriminatory test for B. abortus infections.

Animals↗
PubMed1997

Detection of Mycobacterium avium subsp. paratuberculosis in ovine tissues and blood by the polymerase chain reaction.

A direct polymerase chain reaction (PCR) test was applied to DNA extracted from blood, liver, ileocecal lymph node and ileum from twelve ewes in poor condition with histologically confirmed paratuberculosis and ten clinically normal sheep which had no evidence of paratuberculosis. The assay was compared with four serological tests: complement fixation test (CFT), gel diffusion test (AGID) and two enzyme-linked immunosorbent assays (ELISA). The PCR detection rate of Mycobacterium avium subsp. paratuberculosis, when results of single tests were interpreted in duplicate, was 72% for ileocecal lymph node, 90% for liver, and 100% for ileum in sheep with confirmed paratuberculosis. A single PCR test detected the target DNA in 66% of 0.5 ml blood samples. Sensitivities of serological tests compared with histological diagnosis were: 33% for CFT, 66% for AGID, 75% for the Central Animal Health Laboratory (CAHL) ELISA, and 83% for the 'modified' Commonwealth Serum Laboratories (CSL) ELISA. The PCR assay gave no positive reaction in samples collected from 10 sheep considered to be free of paratuberculosis. Similarly, all four serological tests were also 100% specific. The results raise some hope for the development of a PCR-based test using liver biopsy specimens, or possibly blood, in the diagnosis of paratuberculosis in sheep.

Animals↗
PubMed1999

The efficacy of the skin delayed-type hypersensitivity using a Brucellin prepared from a mucoid strain of Brucella abortus to detect brucellosis.

Eight-hundred-and-ninety-six cattle belonging to herds officially designated Brucella-free, and 190 cattle belonging to infected herds were tested with the skin delayed-type hypersensitivity (SDTH) test, using brucellin (273) prepared from a mucoid strain of Brucella abortus. An increase in skinfold thickness > or = 2 mm was considered a positive SDTH test. The serum agglutination test, complement fixation test and bacteriological examination were used to confirm SDTH test results. Results show that 6 of the 896 uninfected cattle tested positive in the SDTH test, indicating a 99.3% specificity. Of the 44 cattle that tested serologically or bacteriologically positive, 33 tested positive in the SDTH test, indicating a 75% sensitivity. The value of the SDTH test was demonstrated by its ability to detect infection earlier than serological tests, and by confirming infection in cattle with ambiguous serological test results. An increase in skinfold thickness > or = 1 mm in cattle in suspected herds should not be ignored, as it may indicate specific sensitization. We recommend the use of the SDTH test in combination with serological tests for early diagnosis of brucellosis in cattle.

Animals↗
PubMed1984

Monoclonal antibodies distinguish phase variants of Coxiella burnetii.

Monoclonal antibodies (MAbs) directed against phase I and II variants of Coxiella burnetii were produced by fusing myeloma SP2/O-AG 14 cells with spleen cells from mice immunized with the chloroform-methanol extraction residue of phase I whole cells. Two hybridoma clones which distinguished the phase variants by microimmunofluorescence assay were isolated and characterized. The MAbs showing specificity for phase I cells (MAbI-1, immunoglobulin G, subclass 3 kappa) reacted with the hot phenol-water extract of phase I C. burnetii in immunodiffusion and enzyme-linked immunosorbent assays. MAbI-1 reacted with high-molecular-weight components from phase I phenol-water extract and whole cell in an immunoblot assay. Specificity of MAbI-1 for a carbohydrate epitope in the phenol-water extract was demonstrated by periodic acid inactivation of binding by a competitive enzyme-linked immunosorbent assay. Phase I antigenic sites were apparently well represented on the surface of cells as demonstrated by complete fluorescence and microagglutination. The MAb showing specificity for phase II cells (MAbII-1, immunoglobulin G, subclass 2b kappa) reacted with whole cells in the microimmunofluorescence assay, microagglutination test, complement fixation test, and the enzyme-linked immunosorbent assay. MAbII-1 reacted specifically with a 29,500-dalton surface protein as demonstrated by immunoprecipitation of 125I-surface-labeled cells. Although MAbII-1 reacted with detergent-solubilized protein, it did not react with sodium-dodecyl sulfate-denatured protein by immunoblot assay. This protein was not exposed on the surface of phase I cells, but chloroform-methanol extraction of phase I cells exposed the phase II epitope.

Animals↗
PubMed1983

[Clinical and immunological studies of Behçet's disease].

8 patients with clinically diagnosed Behçet disease were immunologically investigated. Uveitis was present in 7 of these patients. Although uveitis is a rare presentation of Behçet's disease, it tends to be bilateral when it does occur and to involve both the anterior and posterior segments repeatedly. Nowadays it is rare to observe a hypopyon, thanks to early initiation of therapy. In the late stages, recurrent vitreous haemorrhage complicates the course of the disease and can lead to blindness. HLA-B5 can frequently be demonstrated in patients with Behçet's disease. Detailed serological investigations, as measles hemagglutination inhibition test+complement fixation test (CFT), rubella hemagglutination inhibition test, hepatitis HB2 antigen, adenovirus antigen, varicella zoster CFT, mumps CFT, herpes simplex CFT, anticytomegalovirus IgM and IgG, toxoplasmosis immunofluorescence, tuberculosis Middlebrock-Dubois, were unable to uncover a connection with past or present infections. Determinations of haptoglobulin, lactate dehydrogenase, albumin and ceruloplasmin showed nothing worth remarking. Electrophoresis can indicate the duration of the illness. In 1 patient the lymphocyte adherence inhibition test was abnormal.

Adult↗
PubMedDate not supplied

[Immunological study of antigenic determinants in the isolated hemagglutinin of the influenza A virus (H1N1)].

A preparation of isolated subunits of influenza A (H1N1) virus hemagglutinin was examined for antigenic properties by four serological tests: radioimmunoassay, radial immunodiffusion test, complement fixation test, and hemagglutination inhibition test with hyperimmune polyclonal serum to intact virion as well as with monospecific antibodies to individual antigenic determinants obtained by adsorption technique. In isolated hemagglutinin subunits, radioimmunoassay identified three main virus-specific antigenic sites identical to antigenic determinants in the hemagglutinin of the intact virion. No neuraminidase was found in the hemagglutinin preparation but increased serological activity of host cell antigens was observed.

Animals↗
PubMed1989

[Congenital toxoplasmosis with delayed immune response].

In typical cases the diagnosis "toxoplasmosis connata" is based on clinical symptoms and positive serological findings. When the infection of the fetus occurred a short time before birth the neonate seems still normal and the disease develops in the postnatal period. In such cases the specific antibody production may be delayed. We present a case report with well documented first infection of the mother between the 15th and 30th gestational week but with no specific treatment. The baby was born without clinical signs of a toxoplasmosis infection and developed the disease 2-3 weeks later; the serological test (complement fixation test, KBR) was negative at the 24th postnatal day. Specific antimicrobial therapy could be started after serological conversion between the 4th and 5th postnatal week. Problems of diagnostics and delayed therapy are discussed.

Animals↗
PubMed1987

[Activity of porcine anti-Brucella abortus immunoglobulins in the acid plate agglutination test (APAT)].

Serological activity of swine IgM and IgG against Brucella abortus in RBPT was determined in relation to four other reactions used in Poland for diagnosing brucellosis standard agglutination test, complement fixation test, antiglobulin test, 2-mercaptoethanol test). Isolation of IgG was performed by the method of filtration on Sephadex gel G-200 of swine sera raised against Brucella abortus S19 by double immunization with suspension of killed bacteria. The presence of a certain Ig class in the fractions thus obtained was confirmed by immunoelectrophoresis and immunodiffusion tests. RBPT revealed the reaction of antibodies of IgM and IgG class which proves usability of this reaction diagnosis both early (IgM) and chronic (IgG) infection with brucellosis. Both classes of antibodies mentioned above were active also in SAT and CTT. Also the results obtained in AGT and MET were found interesting. In one of the sera, the absence of incomplete antibodies was observed, whereas positive reaction in antiglobulin test was found in its fractions containing IgG. This phenomenon was determined as concealment of incomplete agglutinins through higher level of complete antibodies in normal serum. In swine (the results were different from those obtained for cattle), apart from incomplete antibodies in IgG class, the presence of these agglutinins in IgM class was noted. On the other hand, the results obtained in MET proved that IgM antibodies of swine were not totally reduced when affected by 2-mercaptoethanol.

Agglutination Tests↗
PubMed1984

[Anti-brucella agglutinins in aborted women].

52 (6.46 per cent) out of 805 women who aborted spontaneously in Gujarat state, India, were found to have positive Brucella agglutin. Infection with brucella was further confirmed by various serological tests (Rapid plate test, standard agglutination test, Rose Bengal test, Coombs' test, complement fixation test, indirect bacterial haemagglutination test, gel diffusion test and determination of C-reactive protein). Culturing 650 blood clots, 300 placentae and 800 samples of urine of women who aborted gave totally negative results. Women who were selected for this study immediately after admission to the Civil Hospital, Ahmedabad, India, came from rural areas and belonged to the farming community. They had a history of contact with animals and were of the lower socio-economic group. The relationship between brucellosis and spontaneous abortion is discussed. The aborted women would most probably have contracted the infection from their domesticated animals, since brucellosis is prevalent amongst the animals in the State of Gujerat.

Abortion, Habitual↗
PubMed1984

[Biological diagnosis of the leptospiroses: technics and interpretations].

According to the chronological data of Physio-Pathology of leptospiroses, diagnosis is: Direct: isolation of the germ in the beginning of the acute phase of the disease: blood culture, culture of cerebrospinal fluid, animal inoculation. Identification is the work of a specialized laboratory. Indirect: demonstration of antibodies. Immunological tests are divided into two groups: Screening tests, available for all laboratories: they give an indication of Leptospirosis. They are carried out during the acute phase: slide macroscopic agglutination test, hemagglutination test, complement fixation test. Confirmatory tests, performed only by specialized laboratories. Interpretation is dependent on the case history of the patient.

Antibodies, Bacterial↗
PubMed1981

[Serological diagnosis of human brucellosis by means of an immunoenzymatic technic (ELISA). II.--Comparison with four other usual reactions (author's transl)].

The authors analysing 553 serums, compare the results given by ELISA, in the diagnosis of human brucellosis, with four other usual serological tests : agglutination, rose Bengal plate agglutination test, complement fixation test, immunofluorescence. In the ELISA standard study and the research of specific M component, they can estimate, experimentally, the minimal absorbance necessary for concluding in positivity. They show the excellent specificity and sensitivity of this assay, its performances are almost the same as the immunofluorescence ones. Among 55 positive serums in one assay at least 83,6% are positive in both tests ELISA and IIF and 90,9% are detected by ELISA alone.

Brucellosis↗
PubMed1978

[Experimental studies on the affinity of Toxoplasma gondii to various organs of mice (author's transl)].

In response to their alleged "uterus affinity" the organotropism of various Toxoplasma strains was investigated in the female mouse. Using quantitative histological (immunofluorescence) and serological (Sabin-Feldman-dye test, complement fixation test), we examined the brain, heart, lung, spleen, striated muscle, uterus and ovaries. The following results were obtained: All four of the Toxoplasma strains (ALT, DX, WEISS, GAIL) showed a definite neurotropism. Located in the brain were one hundred times as many cysts as in the sexual organs and ten times as many as in the reamining organs. The uterus and ovary show a low susceptibility, invasion rarely occuring. An "uterus affinity" could not be confirmed. All four Toxoplasma strains showed the same affinity for the various organs. The strain ALT showed the most virulence and formed the most cysts.

Animals↗
PubMed1993

Transmission of brucellosis from reindeer to cattle.

Sixteen reindeer (Rangifer tarandus tarandus) naturally infected with Brucella suis biovar 4 were penned with 6 male and 2 female cattle for 30 days, then removed and euthanatized. During this period, 5 reindeer had fawns, and 2 reindeer aborted. Brucella suis biovar 4 was recovered from all adult reindeer at necropsy. Nine reindeer had B suis biovar 4 in uterus, udder, and/or milk. The cattle were euthanatized 2 months after the reindeer were removed. Clinical or pathologic signs of disease were not observed in the cattle. Brucella suis biovar 4 was isolated from 2 male and from both female cattle at necropsy. The female cattle had positive reactions on the buffered plate antigen test, brucellosis card test, tube agglutination test, complement fixation test, and indirect enzyme immunoassay for most of the experiment, but the males had inconsistent reactions on these tests. The indirect enzyme immunoassay was the only test to detect all cattle from which bacteria were cultured. This study revealed that caution is warranted before moving reindeer or caribou into areas of traditional agriculture.

Abortion, Veterinary↗