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PubMed1962

Diagnostic tests for thyroid antibodies: a comparison of the precipitin and latex-fixation (Hyland TAI) tests.

The clinical significance of thyroid antibodies is discussed and it is concluded that, of the antibody tests which have been extensively applied, the precipitin test is the most useful for diagnostic purposes. The recently introduced Hyland TA test is compared with the precipitin test. The TA test gives a rapid result and is slightly more sensitive, but it remains undecided whether a true positive result is always indicative of clinically important degrees of chronic thyroiditis. The TA test also gives occasional false positive results, not indicative of antibody to thyroglobulin. Furthermore, approximately 12% of precipitin-positive sera from patients with Hashimoto's disease give negative TA tests, and since these also have low titres, or are negative, in the tanned red cell haemagglutination test, the precipitin test is the only simple method of demonstrating the antibody concerned. In spite of these disadvantages, the TA test is regarded as a useful procedure, and there are advantages in using both the precipitin and TA tests together for routine diagnostic purposes. A modification is described whereby the TA test reagent may be used to titrate antibody to thyroglobulin.

Antibodies↗
PubMed1976

Grouping of beta-haemolytic streptococci by using coagglutination, precipitation or bacitracin sensitivity.

This study was made to compare coagglutination to precipitin test in grouping beta-haemolytic streptococci from clinical specimens and to investigate the accuracy of the bacitracin test in identification of group A streptococci. Results of grouping 126 strains with coagglutination and precipitation were identical in all except two cases. These two strains were nongroupable with precipitation but appeared as group B and C by coagglutination. When the distribution of group A, B, C and G streptococci in various clinical sources was investigated it was found that group B strains were the most frequently (41 per cent) isolated streptococci and even in isolates from pharyngeal swabs their proportion was 33 per cent. The accuracy of the bacitracin test in identification of group A streptococci was unsatisfactory as 26/62 (42 per cent) strains reported as group A by using this test were in fact group B, C or G streptococci. One of the reasons for this high number of false positives appeared to be the medium used for the preparation of the blood agar plates. In view of the frequent occurrence of non-A-streptococci in clinical specimens and high incidence of false positive in the bacitracin test it is suggested that this test should be replaced by a more efficient method of serological grouping.

Agglutination Tests↗
PubMed1992

Pre- and post-treatment immunodiagnostic evaluation in human schistosomiasis mansoni.

Schistosomiasis control seems to be different in countries were low parasitic burden and asymptomatic clinical patients are the features of majority of cases. Immunological methods must substitute the traditional coprologic techniques used for some decades in the Control Program. Circumoval Precipitin Test (COPT), intradermal test and ELISA with soluble egg antigen (SEA) are evaluated for using as tools for seroepidemiologic studies. COPT and ELISA were performed after treatment to known their utility when impact of chemotherapy must be assessed. One hundred sixty five persons were followed up 3, 6, 9 and 12 months after treatment. The mean sensitivity of COPT studied by age groups was 95.6% which is very important considering that 88.4% of the studied population excreted less than 100 eggs/gr of feces, while sensitivity of intradermal test was 58.2%. Children showed the highest reactivity to COPT. When treatment is effective, COPT reactivity progressively diminish until become negative one year later. In the non cure group, the COPT reactivity diminished but never below 20%. ELISA-SEA did not modify one year after treatment. Effort should be made to isolate fractions of eggs of Schistosoma mansoni whose antibodies disappear after treatment.

Adolescent↗
PubMed1957

Differentiation of group A streptococci with a common R antigen into three serological types, with special reference to the bactericidal test.

In further study of streptococci having the R antigen, the bactericidal test has been used instead of the mouse protection test in investigating the type-specific M antigens of these organisms. The results have been confirmed by M anti-M precipitin tests, and a correlation between the M and T antigens of the strains has been shown. On the basis of a specific M antigen, type 28 has been shown to comprise Griffith's strain Small and four other R-containing strains. A number of other strains previously thought to belong to type 28 on the basis of R antigen reactions have now been identified as belonging either to type 2 or to a new type, designated 48, which shows a one-way cross-relationship to type 13. The bactericidal test is suggested as a useful method for assessing M antigen in group A streptococci and for establishing type-specificity by means of a biological test which is more widely applicable than the standard mouse protection test.

Animals↗
PubMed1976

Purification and immunochemical characterization of type e polysaccharide antigen of Streptococcus mutans.

The type-specific antigen of Streptococcus mutans strain MT703, serotype e, has been chromatographically purified and characterized. Two chromatographic fractions were obtained from saline extracts which reacted with both anti-MT703 whole-cell serum and Lancefield group E serum. The major fraction (eI) was identified as a polysaccharide composed of 37% glucose, 56% rhamnose, 5% protein, and 0.3% phosphorus, whereas the minor fraction (eII) contained 66% protein in addition to 10% glucose and 17% rhamnose. The immunological specificity of these antigens was found to be the same by immunodiffusion in agar gel. Another fraction with a negative charge (eIII) reacted with polyglycerophosphate antisera from Streptococcus mutans and Streptococcus pyogenes. For comparison, the MT703 antigen in a hot trichloroacetic acid extract (eA) and the group E antigen from a saline extract of cells of strain K129 (EI) were similarly purified by anionic ion-exchange chromatography. Although the ratio of glucose and rhamnose in eA was 1:0.9 and in eI and eII approximately 1:1.5, reactions of identity were obtained in gel diffusion against specific anti-e serum. This difference in ratio is probably a result of the extraction procedures. Both the type e and group E antisera were reactive with both eI and EI antigens. The adsorption of group E antiserum with MT703 cells removed all E antibody, whereas type e-specific antibody remained after adsorption with K129 cells. These results suggest that eI antigen possesses both e and E specificities, whereas EI possesses E only. These findings were supported by the quantitative precipitin test and immunodiffusion and/or immunoelectrophoretic patterns in agar gel. Methyl-beta-D-glucopyranoside markedly inhibited the precipitin reaction in both type e and group E sera. However, a significantly stronger inhibition by cellobiose of type e serum than of group E serum indicates that a beta-linked glucose-glucose dimer is the predominant antigenic determinant of the e specificity. The presence of both e and E specificities on a single polysaccharide molecule was demonstrated by the use of purified e antigen released from a specific e-anti-e complex. This antigen reacted with a group E-specific serum as well as a type e-specific serum. An examination of five S. mutans type e strains showed the presence of group E specificity also, whereas the I, II, and IV serotypes of group E streptococci only possessed the group E specificity.

Antigens, Bacterial↗
PubMed1975

Serologic studies in suspected visceral candidiasis.

Twenty-six healthy controls and 45 patients with clinically suspected candidiasis were studied utilizing precipitin determination by double immunodiffusion, agglutinin titers, and presence of clumping factor by microscopy. The data are used to evaluate the specificity, reproducibility, and ease of performance of the procedures. Our results indicate that there is considerable overlap in agglutinin titers in patients with or without visceral candidiasis and that determination of clumping factor by microscopy only is inadequate for diagnosis. Precipitin tests were positive in 80% of patients with visceral candidiasis (exceptions were highly immunosuppressed hosts). This test is easily performed, reproducible, and can be applied in any general hospital laboratory. Neither agglutinin nor precipitin determination appears to be applicable to determining duration of therapy.

Agglutinins↗
PubMed2005

Purification of potato virus X and preparation of its antiserum.

Potato virus X (PVX) isolated from the potato leaf and tuber samples which were collected from various fields in Damavand and Ardabil. The initial isolations of the virus were made from potato by mechanical inoculation on Gomphrena globosa L. and Chenopodium spp. that produce local lesion, and then it causes mosaic on Nicotiana spp. and Datura stramonium L. An isolate of the virus inoculated to Nicotiana glutinosa L. and it was maintained throughout the work. Sap from infected N. glutinosa was ineffective after dilution to 10-6, 10 minutes at 70 degrees and 10 weeks at room temperature. The virus was readily purified from infected leaves and the best protocol was Moreira & Jones 1980 than the other 2 methods of Fribourg 1975 and Shepard & Shalla 1972. Antisera were prepared against native, degraded proteins and micro precipitin test showed that both antisera had a 1/512 titer. Precipitin lines with D - Protein antiserum was better of the native protein antiserum in agar double diffusion test than treated with SDS. The isolate of the virus was not transmitted by none of 2 species of Cuscuta but transmitted from infected leaves to healthy plants with sap inoculation without using Carburandum. This isolate showed positive reaction with gamaglubulin in kate received from CIP centre.

Enzyme-Linked Immunosorbent Assay↗
PubMed1981

Characterization of the glycoprotein antigens which mediate the Schistosoma japonicum circumoval precipitin reaction.

The circumoval precipitin test is a serological test used for diagnosis of schistosomiasis japonica. Soluble egg antigens of Schistosoma japonicum block the formation of the circumoval precipitin by serum from infected humans. Consequently, circumoval precipitin inhibition was used to monitor purification of the soluble egg antigens of S. japonicum. Crude egg antigens were separated into protein and glycoprotein fractions by lectin chromatography on concanavalin A Sepharose. The glycoprotein fraction produced two intense precipitin lines upon immunodiffusion analysis with human chronic infection sera. The protein fraction produced two faint precipitin lines which did not cross-react with those of the glycoprotein fraction. The glycoprotein fraction contained 90% of the circumoval precipitin inhibitory activity. Isoelectric focusing of (125)I-labeled concanavalin A Sepharose fractions revealed at least four groups of potential S. japonicum antigens, termed JAG I, II, and III, and a JAG IV complex. These had isoelectric points ranging from 3.2 to 6.7. In these respects, the S. japonicum egg antigen glycoproteins are similar to those of Schistosoma mansoni. The glycoproteins were further separated by diethylaminoethyl ion-exchange chromatography. On immunodiffusion analysis it was found that one of the strong Ouchterlony precipitin lines was associated with glycoproteins that did not adsorb to diethyl-aminoethyl columns, whereas the second Ouchterlony precipitin was heterodisperse, being present in the first, second, and third of the four peaks eluted from the diethylaminoethyl column. Immunoelectrophoresis of the diethylaminoethyl fractions demonstrated that the antigen present in highest concentration in soluble egg antigen glycoproteins, JAG II, was extremely heterodisperse in its behavior on diethylaminoethyl columns. This is unlike the S. mansoni antigens which can be easily separated by diethylaminoethyl ion-exchange chromatography.

Animals↗
PubMedDate not supplied

Characteristics of Actinomyces pyogenes involved in lameness of male turkeys in north-central United States.

A new condition of clinical lameness in 20 male turkey flocks of North-Central United States, associated with isolation of gram-positive rod bacteria from lesions of osteomyelitis, is characterized. The characterization confirmed the randomly selected isolates as Actinomyces pyogenes based on macroscopic and microscopic observations and 17 biochemical tests. The disease was reproduced within 3 weeks in all male turkeys, following an intravenous challenge at 15 weeks of age. The agar gel precipitin test and immunoblotting confirmed the antigenic similarity of the isolates recovered from the osteomyelitis lesions of lame birds.

Actinomyces↗
PubMed1977

Immunological investigations of Candida albicans in respiratory disease.

1. Tests against rabbit antiserum to Candida albicans showed about 40 protein antigens in cytoplasmic extract compared with two in a commercial test extract, which contained mainly polysaccharide (mannan) antigens. 2. Positive precipitin tests to the mannan preparation were recorded in 40% of 56 asthmatics on systemic corticosteroids and 37% of 56 rhinitis patients not so treated. The titres were slightly higher in the corticosteroid group. There was no increase in precipitins over 0-9 months in asthmatics treated with beclomethasone dipropionate aerosol (BDA) by inhalation, or over 0-12 months in rhinitis patients treated with BDA nasal spray. No positive reactions to the purified protein fraction were recorded. 3. Radioallergosorbent tests for specific IgE antibody showed a higher incidence of positive results with whole C. albicans yeast cells than with purified cytoplasmic protein. There was a higher incidence of positive results to protein in patients on systemic corticosteroids than in the other patients. No change in incidence occurred in asthmatics on BDA. The number of positive results in 56 rhinitis patients increased on BDA from 28 to 37 for yeast cells, and from 7 to 16 for cytoplasmic protein. This was attributed to C. albicans challenge tests. 4. Specific IgA antibodies to yeast cells were detected in 48/56 asthmatics on systemic corticosteroids, and there were no significant changes over 0-9 months on BDA. The corresponding figures for rhinitis patients were 25/56, and again there were no significant changes over 0-12 months on BDA.

Antigens↗
PubMed1975

Interactions between ricinus agglutinin and human IgM and IgG.

Ricinus agglutinin, purified until homogeneous, precipitates serum glycoproteins with terminal nonreducing galactose residues including IgM and IgG. Almost 100% of IgM reacted with anti-IgM and ricinus agglutinin in quantitative precipitin tests. In similar tests, almost 100% of polyclonal IgG was precipitated by excess anti-IgG, whereas only about 10% reacted with ricinus agglutinin. In quantitative precipitin analyses and affinity chromatography experiments with insolubilized ricinus agglutinin and isolated monoclonal IgG1 and IgG3 proteins, only IgG3 proteins reacted with ricinus agglutinin.

Antibodies, Anti-Idiotypic↗
PubMed1989

Serological reactions in sheep and cattle experimentally infected with three Australian isolates of bluetongue virus.

Serums from 103 sheep and 24 cattle experimentally infected with one of 3 serotypes of bluetongue virus isolated in Australia were tested for antibody to bluetongue virus in the serum neutralisation test and the agar gel diffusion precipitin test. Antibody to bluetongue virus was first detected by these tests 8 to 10 days after intravenous infection in 4 sheep that were bled daily for serum analysis. The agar gel diffusion test failed to detect antibody in 28% (29/103) of sheep which had seroconverted in the serum neutralisation test. A further 7% (7/103) of sheep serums were negative in both tests 14 to 22 d after infection. Both tests detected antibody to bluetongue virus in all cattle serums by 10 days after detection of viraemia. In comparison with the intravenous route of infection, extended prepatent periods for the commencement of viraemia resulting from intradermal, subcutaneous and intrauterine routes of infection in the cattle caused corresponding delays in the detection of antibody. For example, one cow that was infected by intrauterine inoculation did not become viraemic until 22 d after inoculation and antibody was not detected until 32 d after inoculation.

Animals↗
PubMed1970

Composition and properties of a group A streptococcal teichoic acid.

Teichoic acid-like material extracted by cold trichloroacetic acid from lyophilized whole cells of streptococci from groups A,D,E,O, and T was shown to give a positive precipitin reaction with group antisera. Similar material from cells of groups B,C,F,G,H,K,L,M,N,P,Q,R, and S did not give a positive reaction with group antisera. The group A material also reacted with anti-E serum; however, the opposite did not occur. A similar result was also obtained on the group T material and anti-O serum. The group A teichoic acid was purified by Sephadex column chromatography, and was shown to be free of cell wall peptidoglycan and polysaccharide, and ribitol teichoic acid. It was composed of glycerol, phosphate, alanine, and glucosamine. Alkaline hydrolysis showed the presence of ester-linked alanine and glucosaminylglycerol. Phosphorus was released from ester linkage by alkaline phosphatase. N-acetylglucosamine produced a 72% inhibition of the precipitin test at a level of 10 mumoles, and d-alanine methyl ester was significantly stronger than the l-alanine ester. A single precipitin band was seen with group A serum. The data indicate that teichoic acid of group A streptococci is a polymer composed of glycerol phosphate and containing N-acetylglucosamine and alanine. Antisera to these streptococci contain antibodies specific for the alanine and the glucosamine linkages. The use of serum containing antibodies to alanine-polyglycerophosphate shows that the occurrence of this type of teichoic acid is widespread among the streptococci.

Acetone↗
PubMed1970

Human fascioliasis in Shropshire.

Five patients with fascioliasis presented with malaise, pruritus, and pain in the right hypochondrium. Eosinophilia, increase in serum gamma globulin, and pyrexia were other features. Four patients treated with oral bithionol recovered completely and it is suggested that this is an effective form of therapy. The double diffusion precipitin test, being speedy and simple, was used as a screening procedure for diagnosis. The source of infection was wild watercress growing in a farm ditch.

Administration, Oral↗