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PubMed1995

[Development of humoral precipitating antibodies to Campylobacter spp. in chickens].

Development of humoral precipitating antibodies against Campylobacter spp. in chickens. The development of precipitating antibodies in chickens was examined by two-dimensional immunodiffusion test after immunization with a formol inactivated vaccine and after subcutaneous and oral application of different live campylobacter serovars. The supernatant of bacterial cells after sonication and centrifugation was used as an antigen in the agar-gel precipitin test. Antisera against different campylobacter serovars showed a high percentage of cross-reactions. In chickens immunized with an inactivated vaccine at an age of 1, 2, 3, 4 and 7 weeks, precipitating antibodies could be demonstrated for the first time at 7 days p.i. Except for 1-week-old birds, sera from the other groups reacted positively at 14 days p.o. After subcutaneous duplication of live organisms to 4-week-old chickens, antibodies could already be demonstrated at 4 days p.i. later in part of the experimental groups. No interrelation could be detected between antibody titers, measured by enzyme-linked immunoabsorbent assay (ELISA), from precipitating sera, as well as from those from non-precipitating sera. Precipitating antibodies and antibody titers in the ELISA were examined in sera from groups of birds infected at an age of 1, 2, 3, 4 and 7 weeks. During the Campylobacter excretion period, a distinct peak of antibody titers occurred in 1- and 7-week old birds, whereas other groups showed a steady increase in titers. Precipitating antibodies were only found in 1- and 2-week-old chickens.

Animals↗
PubMed1980

Serogrouping single colonies of beta-hemolytic streptococci from primary throat culture plates with nitrous acid extraction and Phadebact streptococcal reagents.

The serogrouping of isolated beta-hemolytic streptococcal colonies from throat cultures by a micronitrous acid extraction method employing Phadebact Streptotoccus Test reagents was compared with results obtained with the direct-plate Phadebact procedure and the autoclave and Streptomyces albus enzyme-lysozyme extraction methods. These data were compared with those from the Lancefield grouping obtained with a capillary precipitin test. The micronitrous acid extraction method was modified to yield an uncomplicated method that provides specific coagglutination responses from one beta-hemolytic streptococcal colony that may be collected from a primary blood agar plate either on the end of an applicator stick or from a sweep of an inoculating loop from mixed growth.

Agglutination↗
PubMed1983

Prevalence of serologic types of Pasteurella multocida from 57 species of birds and mammals in the United States.

The serologic types of 265 isolates of Pasteurella multocida collected from 50 species of wild birds and seven species of wild mammals over a 22-yr period were determined with the gel diffusion precipitin test. Antigens prepared from these isolates reacted with reference P. multocida antisera representing serotypes 1, 2, 3, 4, 5, 6, 7, 8, 12, and 15. Antigens from some isolates reacted slightly with antisera from more than one serotype. Overall, gel precipitin reactions involving serotype 1 (65%) and 3 (20%) were the most prevalent.

Animals↗
PubMed1986

Histopathologic and antibody responses of rabbits exposed to aerosols containing spores of Aspergillus fumigatus: comparison of single and multiple exposures.

Resistance to pulmonary aspergillosis was studied in groups of rabbits exposed to aerosolized spores of Aspergillus fumigatus for 15 minutes on successive days for a total of 10, 7, or 4 exposures or a single exposure. The results of the study demonstrated that exposure of rabbits to spores for 15 minutes on 10 successive days did not result in an accumulation of viable spores in excess of those present in the lungs of rabbits exposed a single time. The tissue response in the lungs of the rabbits exposed at multiple times was more intense than that in the rabbits exposed once, but resolution of the lesions occurred similarly in terms of time and completeness of resolution. The duration of the antibody response as determined by a passive hemagglutination test and by enzyme-linked immunosorbent assay correlated with the number of exposures to spores, in that rabbits exposed 10 or 7 times to aerosolized spores remained positive longer than did those exposed fewer times. The results of the precipitin tests in agar gel were negative in all the rabbits but one.

Aerosols↗
PubMed1974

Purification, composition, and serological characterization of histoplasmin-H and M antigens.

To obtain purified H and M antigens suitable as primary standards in the serological diagnosis of histoplasmosis by agar gel double-diffusion tests, H and M reactive components of histoplasmin were fractionated by column chromatography by using Sephadex G-100, Sephadex G-200, and diethylaminoethyl cellulose. Six fractions from diethylaminoethyl cellulose were reactive in agar gel double-diffusion, complement fixation, and capillary precipitin tests. When examined by electrophoresis on acrylamide gel, one M antigen (fraction 2, molecular weight greater than 200,000) and two H antigens (fractions 5 and 6, molecular weight greater than 200,000) each gave essentially a single protein band. In agar gel double-diffusion and complement fixation tests with sera from patients with proven cases of histoplasmosis, blastomycosis, or coccidioidomycosis, these two fractions of H antigen and the one of M antigen reacted only with sera from proven or suspect cases of histoplasmosis and showed reactivity with those sera known to contain only the anti-H or anti-M antibody, respectively. Fraction 2 (M antigen) and fractions 5 and 6 (H antigens) had carbohydrate-to-protein ratios of 1.60, 0.77 and 0.78, respectively. Both antigens contained galactose, glucose, mannose, and hexosamine, with mannose being the predominant sugar. Fraction 2 was characterized by a high proline and glucose content, whereas fractions 5 and 6 contained higher concentrations of galactose, mannose, glycine, and alanine. Each of these products appeared to separate into two active fractions, one of a molecular weight greater than 200,000 and one of a molecular weight less than 35,000. The M antigen component of fraction 2 was still characterized by a high proline content, whereas the H antigen components of fractions 5 and 6 had a high content of glutamic acid, serine, glycine, and proline.

Antigens, Fungal↗
PubMed2001

Longitudinal changes of sensitization to farming-related antigens among young farmers.

BACKGROUND: We have shown previously that the prevalence of allergic sensitization in Tyrolean farming students is high, with a clear relationship to occupational exposure. OBJECTIVES: It was the aim of this investigation to assess longitudinal changes in sensitization and a possible impact on lung function. METHODS: Of the 147 farming students in the original cohort, we could re-examine 42 after a mean interval of 4.0 years. All individuals completed a questionnaire and had spirometry, skin prick tests, total and specific IgE analysis, and testing for precipitating antibodies. RESULTS: As compared to the first study, there was a decrease in the frequency of IgE-mediated allergy (30.1 vs. 54.8%; p < 0.05) and in total serum IgE levels (107.4 +/- 254 vs. 157.8 +/- 304 U/ml; p < 0.001). Conversely, 3 individuals had developed precipitating antibodies de novo, and those who had initially had a positive precipitin test (n = 6) were still positive. A larger-sized estate, the lack of a hay dryer, and the presence of moldy hay were confirmed as risk factors for allergic sensitization. Although there was a slight overall decrease in forced vital capacity, no new cases of occupational lung disease were found. CONCLUSIONS: In young Tyrolean dairy farmers, the prevalence of precipitins is constantly high and rising while IgE-mediated allergy declines. Within 4 years, no clinically relevant impact of allergy on lung function was noticed.

Adolescent↗
PubMed1974

Diagnosis of California (La Crosse) encephalitis by precipitin techniques: a prospective study.

Counterelectrophoresis (CEP) and immunodiffusion (ID) were evaluated prospectively as methods for the early and rapid laboratory diagnosis of California encephalitis (CE). CEP and ID studies were done on paired sera from 127 patients with acute central nervous system infections. After the precipitin tests were completed, conventional hemagglutination-inhibition, neutralizing, and complement fixing antibody titers were measured. The CEP system detected antibodies in 7 (41%) of 17 CE patients during their acute illness and in all 17 patients during convalescence. The ID method was less sensitive; 3 of 17 acute sera and 16 of 17 convalescent sera were ID positive. Comparative precipitin studies indicated that La Crosse virus was the infecting California group subtype in all 17 CE patients. Because CEP can be performed in 1.5 h, is at least as sensitive as hemagglutination-inhibition, neutralizing, and complement fixing tests, and can detect prospectively 41% of CE patients during their acute illness, it is recommended as a rapid diagnostic test for CE.

Antibodies, Viral↗
PubMed1968

Comparative studies of antigens from Mycoplasma mycoides and Escherichia coli.

Extracts of sonically disrupted Mycoplasma mycoides and Escherichia coli were fractionated by sucrose density gradient centrifugation. The presence of antigen in each of the fractions was determined by complement-fixation and agar-gel diffusion precipitin tests, in which cow, pig, and rabbit anti-M. mycoides sera and rabbit anti-E. coli serum were used. Fractions of M. mycoides, with a buoyant density of 1.225 or lower, fixed complement with cow and pig anti-M. mycoides sera. These fractions also formed precipitin lines with pig antiserum. Fractions in the buoyant density range of 1.10 to 1.20 fixed complement with rabbit anti-E. coli serum, but precipitin lines were not formed. All E. coli fractions fixed complement and gave precipitin lines with homologous serum. But fractions in the buoyant density range of 1.10 to 1.20 had minimal complement fixation with heterologous M. mycoides sera. The cross-reacting antigens in M. mycoides and E. coli had a buoyant density of 1.10 to 1.20; the specific antigens were isolated from M. mycoides at a buoyant density of 1.08 to 1.02.

Animals↗
PubMed1984

Effect of lysolecithin analogues on plant viruses.

Newly synthesized lysolecithin analogues 2-0-hexadecyl-glycero-3-phosphocholine (1) and its methyl (2), ethyl (3) and benzyl (4) derivatives were tested with regard to the anti- phytoviral effect on potato virus X ( PVX ), red clover mottle virus ( RCMV ) and tobacco mosaic virus (TMV). The first two compounds (1, 2) reduced markedly the content of PVX and RCMV in systemically infected host plants as evidenced by precipitin test and bio-assay. Whereas compounds (1), (2) and (3) did not significantly influence the local lesion formation caused by TMV, compound (4) increased the number of necrotic lesions. In the presence of all four lysolecithin analogues, especially of (1), (2) and (3) the infectivity of virus particles was reduced.

Antiviral Agents↗
PubMed1975

Serological diagnosis of California (La Crosse) encephalitis by immunofluorescence.

A method of indirect immunofluorescence was developed and examined retrospectively as a serological test for the laboratory diagnosis of California encephalitis (CE). LaCrosse virus immunofluorescence immunoglobulin (Ig) G and IgM studies were done on paired sera from 50 patients with acute central nervous system infections. CE had been documented in 25 patients by hemagglutination inhibition, neutralizing, complement fixing, and/or precipitin tests. Five (20%) of the acute and 16 (64%) of the convalescent sera from CE patients had La Crosse IgM antibodies. Seven (28%) of the acute and all of the convalescent CE specimens had La Crosse IgG antibodies. Titers ranged from less than 4 to 256. IgG antibodies were present in all 11 sera collected 1 to 2 years after CE, but IgM antibodies were absent. The 25 serum pairs from patients who did not have CE were negative for IgM and IgG antibodies. This study indicated that La Crosse immunofluorescence antibody tests were as sensitive and specific for CE as conventional hemagglutination-inhibition tests, and would detect at least 20% of patients during their acute illness.

Antibodies, Viral↗
PubMed1981

Isolation of Moraxella bovis ribosomes and their subsequent use in a vaccine against infectious bovine keratoconjunctivitis.

A study was conducted to determine whether a Moraxella bovis ribosomal vaccine would protect calves from infectious bovine keratoconjunctivitis (IBK). Each of 16 calves were given 2 inoculations 21 days apart. Twenty-one days after the 2nd inoculation, 8 of the calves were challenge exposed with a homologous strain culture and 8 calves were challenge exposed to a heterologous strain culture of M bovis. Sedimentation velocity analysis of the ribosomes used in this study indicated that they were mostly 30S and 50S subunits. Chemical assays indicated that the ribosomes were composed of 64% to 65% RNA and 35% to 36% protein. The cesium chloride buoyant density of the ribosomes was 1.62 g/ml. Ribosomes used as antigen gave 1 line of precipitation in a gel-diffusion precipitin test with hyperimmune serum against the whole-cell antigen of the homologous strain of M bovis. The eyes of all the experimentally exposed calves became infected and all calves developed clinical signs of either unilateral or bilateral IBK. None of the sera of the vaccinated calves had detectable precipitins against the ribosomal antigen at the time they were challenge exposed, but most of the sera had precipitins against whole-cell and pilus antigens. The results indicate that M bovis ribosomes, although similar to other bacterial ribosomes, did not protect cattle against IBK.

Animals↗
PubMedDate not supplied

[Standardization of ELISA IgM and IgA for immunodiagnosis of human trichinosis].

An ELISA test for trichinosis using as antigen a larvae soluble fraction from Trichinella spiralis was carried out for the detection of IgM and IgA specific antibodies in 45 serum samples from patients confirmed or suspected to have trichinosis by strong clinical and epidemiological evidences. All the patients had positive serology detected by precipitin test, bentonite floculation test, indirect hemagglutination test and ELISA IgG test. The cut-off value was determined using two criteria. Criterion A was determined in each plate, using three positive controls and two negative ones; the average of the negative controls and the weakest positive control, multiplied by a 1.2 factor was, considered the cut-off value. Criterion B was determined using the average plus three standard deviations from 64 apparently healthy persons serum samples. In both cases, three serum dilutions (1:10, 1:100 and 1:500) were used. The sensitivity of ELISA IgM was 100.0, 93.3 and 82.2% using serum dilutions of 1:10, 1:100 and 1:500 respectively (criterion A) and 100.0, 97.8 and 95.6% for the same dilutions (criterion B), whereas the values for ELISA IgA were: 100.0, 91.1 and 86.7% (criterion A) and 100.0, 100.0 and 91.1% (criterion B). In order to find out the specificity of ELISA IgM and ELISA IgA, additional 118 serum samples from individuals with other parasitoses, such as cysticercosis (18) hydatidosis (39), fascioliasis (12), toxocariasis (30), Chagas' disease (12) and individuals with non-specific eosinophilia (7), were also tested. ELISA IgM presented a specificity of 92.3, 93.4 and 97.3% (criterion A) and 96.2, 97.8 and 97.8% (criterion B) whereas the results for ELISA IgA were 97.8, 98.9 and 99.4% (criterion A) and 98.4% for the 1:10 and 1:100 dilutions and 100.0% for the 1:500 dilution (criterion B). The positive predictive values of ELISA IgM were 76.3, 77.8 and 88.1% (criterion A) and 86.5, 91.7 and 91.5% (criterion B) whereas the negative ones were 100.0, 98.3 and 95.7% (criterion A) and 100.0, 99.4 and 98.9% (criterion B). The positive predictive values of ELISA IgA were 91.8, 95.3 and 97.5% (criterion A) and 93.8, 93.8 and 100.0% (criterion B) whereas the negatives ones were: 100.0, 97.8 and 96.8% (criterion A) and 100.0, 100.0 and 97.8% (criterion B). The use of ELISA IgM and ELISA IgA in the immunodiagnosis of trichinosis is discussed.

Adult↗
PubMed2002

Diagnosis of brucellosis by serology.

Serological diagnosis of brucellosis began more than 100 years ago with a simple agglutination test. It was realized that this type of test was susceptible to false positive reactions resulting from, for instance, exposure to cross reacting microorganisms. It was also realized that this test format was inexpensive, simple and could be rapid, although results were subjectively scored. Therefore, a number of modifications were developed along with other types of tests. This served two purposes: one was to establish a rapid screening test with high sensitivity and perhaps less specificity and a confirmatory test, usually more complicated but also more specific, to be used on sera that reacted positively in screening tests. This led to another problem: if a panel of tests were performed and they did not all agree, which interpretation was correct? This problem was further compounded by the extensive use of a vaccine which gave rise to an antibody response similar to that resulting from field infection. This led to the development of an assay that could distinguish vaccinal antibody, starting with precipitin tests. These tests did not perform well, giving rise to the development of primary binding assays. These assays, including the competitive enzyme immunoassay and the fluorescence polarization assay are at the apex of current development, providing high sensitivity and specificity as well as speed and mobility in the case of the fluorescence polarization assay.

Agglutination Tests↗
PubMed1976

Serological diagnosis of infection of the urinary tract by yeasts.

Precipitins to mannan and cytoplasmic antigens of Candida albicans and Torulopsis glabrata were determined in 25 patients with colonization of the bladder urine by yeasts and in 25 control patients with bacteriuria. Precipitins were present in 64% of the patients with funguria and in 56% of the patients with bacteriuria. There was no correlation between the reactions obtained and the clinical significance of the yeast colonization. It is suggested that a single precipitin test is unhelpful in the assessment of the significance of urinary colonization by yeasts in hospital patients.

Antibodies, Fungal↗
PubMed1977

The uptake of Aspergillus fumigatus protein by serum IgG antibody from patients with pulmonary aspergillosis.

A method is presented for measuring the uptake of Aspergillus fumigatus protein by IgG antibodies from human serum. The human IgG is first isolated with an anti-IgG conjugated immunosorbent and then incubated with radio-iodinated A. fumigatus protein. A group of twenty-three control sera gave the same background levels as tests without sera. The highest uptake of A. fumigatus protein was given by the sera of patients with aspergilloma, and lower values were obtained with six out of thirteen sera from patient's with asthma and twenty-five out of twenty-eight sera from patients with asthma and pulmonary eosinophilia, i.e. allergic bronchopulmonary aspergillosis. These results were in agreement with precipitin tests, Inhibition studies with unrelated antigens showed that the reactions were specific for the A. fumigatus protein, of which more was bound by test sera than with a crude extract.

Antibodies, Fungal↗
PubMed1983

Activation of complement in C-reactive protein positive sera by phosphorylcholine-bearing component isolated from parasite extract.

Phosphorylcholine-bearing component levels in extracts of various parasites were determined by a capillary precipitin test using anti-phosphorylcholine Ig A myeloma protein. TEPC-15. Phosphorylcholine was demonstrated as a structural component not only in nematodes but also in trematodes and cestodes. The phosphorylcholine-bearing component was isolated from an extract of Toxocara canis larvae using a TEPC-15-Sepharose 4B column. The component reacted with C-reactive protein in sera to form one precipitin line in immunoelectrophoresis. The component provided two Brilliant Coomassie Blue positive bands in SDS-polyacrylamide gel electrophoresis. It reacted with C-reactive protein to activate complement in serum.

Animals↗
PubMed1986

[Fractionation of antigen for ELISA of bovine fascioliasis]

In order to obtain the most specific and sensitive antigen from crude antigens of Fasciola hepatica for the immunodiagnosis of bovine fascioliasis by the enzyme linked immunosorbent assay(ELISA), phosphate buffered saline extract of F. hepatica was prepared. The crude extract was fractionated into 7 antigens using Sephadex G-100 column chromatography. Seven fractionated antigens were applied to ELISA, precipitation test and intradermal test, respectively. Results obtained are as follows: The specificity (95 per cent confidence interval in negative sera of bovine fascioliasis; Mean+2 x SD of absorbance ) of the first (MW>150,000) and the second antigens (MW 120,000) were 93.7 per cent, but those of others including crude antigen showed 100 per cen.t. The sensitivity (positive sera of bovine fascioliasis having higher values with compared to the criterion) of the first, the sixth (MW 16,000) and the seventh antigen (MW<5,000) were 91.6 per cent, 87.5 per cent and 0 per cent, respectively, but those of others showed all 100 per cent. The absorbance by ELISA using the fifth antigen (MW 26,000) was 8.43-folds higher in the positive sera than that in the negative sera. This could be used as one of the most specific antigens for the immunodiagnosis of bovine fascioliasis. In Ouchterlony test, precipitin lines were not found in the sera naturally infected with F. hepatica, but some were found in the sera of rabbits immunized with the crude antigens. The numbers of precipitin lines in the sera of rabbits were different in the different fractionated antigens. They were 6 in the crude, 2 in the second and the third antigens, 1 in the forth, the fifth and the sixth antigens and absent in the seventh antigen, respectively. The wheal size for the bovine infected with F. hepatica was 2.46+/-0.15 cm in the intradermal test antigen (saline extract of F. hepatica) supplied by the Veterinary Research Institute, Rural Development Administration, Korea. The wheal size of the first, the second and the third antigens were larger than that of intradermal test antigen, whereas those of the forth, the fifth, the sixth and the seventh antigens showed smaller than that of the intradermal test antigen. The results suggest that the fifth antigen may be specific antigen for the immunodiagnosis of bovine fascioliasis.

Journal Article↗