Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PRECIPITINS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources

Immunological parameters in farmers with chronic lung disease.

The serum concentrations of IgG, IgA, IgE, C3 (B1A), C4 and alpha 1 AT were measured in 8 farmers with chronic pneumopathy, who showed precipitins against M. faeni or T. vulgaris in the serum. A group of 8 precipitins negative farmers who had worked in barn and 28 normal subjects served as control. IgG were elevated in the patients with detectable precipitins; levels of serum IgA in patients with precipitating antibody were lower than in the subjects without them. The mean levels of C3 were significantly lower in the farmers with detectable precipitins than in the farmers without precipitating antibody and in the control group.

Adult↗

Multiple forms of rat liver cytochrome P-450. Immunochemical evidence with antibody against cytochrome P-448.

Purified hepatic cytochrome P-448 from 3-methylcholanthrene-treated rats was used to produce antibody in rabbits. The cytochrome P-448 antibody (IgG fraction) isolated from immune rabbit serum is quite specific and precipitates purified rat liver cytochrome P-448 at low antibody to protein ratios when assayed by the Ouchterlony double diffusion technique. Purified hepatic cytochrome P-450 from phenobarbital-treated rats cross-reacts poorly with the cytochrome P-448 antibody as do purified rabbit hepatic cytochrome P-448 and P-450. No cross-reaction is observed with purified cytochrome P-450 from beef adrenal mitochondria or from Pseudomonas putida in Ouchterlony double diffusion experiments. The cytochrome P-448 antibody produces a single distinct precipitin band with purified rat cytochrome P-448. In contrast, purified liver cytochrome P-450 from phenobarbital-treated rats gives three precipitin bands, all of which contain hemeprotein as judged by benzidine staining. At least two of the three precipitin bands are immunochemically different from the precipitin band formed with cytochrome P-448. When added to the reconstituted system, the cytochrome P-448 antibody inhibits purified rat cytochrome P-448- and P-450-supported N-demethylation of benzphetamine, O-deethylation of ethoxycoumarin, hydroxylation of benzo[a]pyrene, and the hydroxylation of testosterone at the 6beta, 7alpha, and 16alpha positions. Antibody inhibits cytochrome P-448-supported metabolism more than cytochrome P-450-supported metabolism except for benzo[a]pyrene hydroxylation at low antibody to hemeprotein ratios. In addition, the pattern and extent of inhibition of the cytochrome P-450 system depends on the substrate used, suggesting that multiple forms of the hemeprotein are present in the purified preparation from phenobarbital-treated rats. The observed patterns of immunoprecipitation and inhibition of catalytic activity indicate that (a) cytochrome P-448 from 3-methylcholanthrene-treated rats is immunochemically different from cytochrome P-450 from phenobarbital-treated rats, and (b) there appear to be at least three hemeprotein forms in the purified cytochrome P-450 preparation from phenobarbital-treated rats.

Animals↗

Antigenic composition of Litomosoides carini.

Three different phosphate buffered saline extracts of Litomosoides carini were prepared and examined by gel diffusion, immunoelectrophoresis and disc polyacrylamide gel electrophoresis using sera from infected cotton rats and antisera from hyperimmunized rabbits. Using disc polyacrylamide gel electrophoresis, up to 22 protein, 6 lipoprotein and 4 glycoprotein bands were identified. A minimum of 8 precipitin lines were detected by gel diffusion and a maximum of 11 precipitin arcs by immunoelectrophoresis when pooled rabbit antiserum was used. Using infected cotton rat sera, fewer number of precipitin lines and arcs were detected. Two precipitin arcs did not have a counterpart on examination against pooled rabbit antiserum. The importance of these two specific antigenic components for use in immunodiagnosis of human filariasis has been discussed.

Animals↗

Serology of paracoccidioidomycosis. II. Correlation between class-specific antibodies and clinical forms of the disease.

Untreated and previously treated patients with paracoccidioidomycosis were studied for: (i) serum levels of total IgG, IgM and IgA immunoglobulins, by radial immunodiffusion and Paracoccidioides brasiliensis (Pb) antibodies, by indirect immunofluorescence; (ii) correlation between their levels with the clinical forms of the disease; (iii) correlation between the serum titres obtained by tube precipitin with those of anti-Pb IgG, IgM and IgA. In the untreated group, serum IgG levels were significantly increased in patients with the more systemic forms of the disease, especially the acute progressive form. Serum IgA levels were significantly increased in all patients with no statistical difference between clinical forms. Serum IgM levels were normal in all patients. Anti-Pb IgG, IgA and IgM were detected in 97.5%, 32.5% and 45.0% of all cases, respectively. There was a sharp tendency towards higher levels of anti-Pb IgG among those with the acute progressive form (83.4%) in relation to the chronic, more localized forms, mixed form (68.0%) and isolated organic form (55.5%). In the untreated and previously treated group sera, there was positive correlation between the level of anti-Pb IgG and positivity for the tube precipitin test, suggesting that the precipitin-type antibodies are of the IgG class. Broadly, the present data demonstrate a polyclonal activation of the humoral immune system in paracoccidioidomycosis, with a positive relationship between serological results and severity of the disease.

Adult↗

Relationship between attachment loss and precipitating serum antibody to Actinobacillus actinomycetemcomitans in adolescents and young adults having severe periodontal destruction.

The purpose of this study was to determine if adolescents and young adults with severe periodontal disease had precipitating serum antibody reactive with Actinobacillus actinomycetemcomitans, and, if so, to correlate presence or absence of the precipitin with clinical patterns of periodontal destruction. Double diffusion in gel was used to detect precipitins. Test and known positive standard sera were run in different wells against a common well containing a minute of sonicates from two strains of A. actinomycetemcomitans (Y4 and N27). Periodontal loss of attachment was measured with a probe on four surfaces per tooth; missing and unerupted teeth were noted with the aid of radiographs. Precipitating antibody was seen in 77% of sera from 22 subjects with localized juvenile periodontitis, 40% of 35 young subjects with more generalized severe disease, and 2% of 44 periodontally healthy individuals. About 80% of the positive reactions were with strain Y4. Within the diseased groups, there were significantly fewer involved teeth in subjects with precipitating antibody (Ab+) than among those in whose sera precipitins were not seen (Ab-). Comparisons of the distribution and severity of involved teeth between Ab+ and Ab- subjects were consistent with an hypothesis that high levels of antibody specific for A. actinomycetemcomitans have a protective effect against periodontal destruction.

Actinobacillus↗

Complement consumption in the diagnosis of pigeon breeders' disease.

Two laboratory techniques have been applied for the diagnosis and follow-up of pigeon breeders' disease, viz. detection of precipitins against specific antigens from pigeon droppings and assays of human haemolytic complement (huC) consumption by pigeon dropping antigens. A simple laboratory test of huC consumption by pigeon antigens is described, revealing high huC sensitivity in almost all sera of pigeon breeders with manifest or former disease. False-positive results were seldom observed. Discontinuation of antigen exposure and/or corticosteroid therapy had no effect on the huC consumption level in the test system, despite precipitin titres falling below the level of detection. Titration studies revealed an initial decrease of the huC-consuming serum factors, but titres settled at a definite constant level, even after antigen avoidance for many years. Combined application of both the precipitin test and the huC consumption test appears to be a good procedure for the laboratory diagnosis of pigeon breeders' disease.

Alveolitis, Extrinsic Allergic↗

Detection of specific antibodies in immune complexes of farmer's lung patients.

The authors examined 23 precipitin-positive symptomatic patients with Farmer's Lung(FL) and compared them to different groups of exposed asymptomatic precipitin-positive(EAPP) and precipitin- negative(EAPN) farmers. The sera were tested using several techniques (i.e., immunodiffusion and ELISA for specific antibodies; polyethylene glycol [PEG] for circulating immune complexes [CIC]) in an attempt to find an in vitro test correlated with the disease which could also provide an insight into the pathogenic mechanisms of Farmer's Lung. Circulating immune complexes formed by IgG were significantly higher in Farmer's Lung patients than in EAPP subjects. In polyethlyene glycol precipitates from Farmer's Lung patients, specific antibodies found by ELISA correlated well with serum positivity, but they were not found in EAPP subjects. The possibility that the circulating immune complexes found were Ig aggregates was ruled out, as was the possibility that the antibodies found in the polyethylene glycol precipitate were also due to an unspecific link. The authors suggest that the circulating immune complexes of Farmer's Lung patients contain specific specific antibodies and that since their composition is different in EAPP subjects, these circulating immune complexes may play a role in the pathogenesis of the disease.

Antibody Specificity↗

Epidemiologic and immunologic studies in processors of the king crab.

Following the report of ten cases of respiratory illness in processors of frozen king crab, we investigated the conditions of work and the pulmonary and immunologic status of the workers in three crab-processing and one fish-packing (control) plant. Pulmonary function was measured before and after work, and skin tests were performed in subgroups matched for age, sex, and duration of current employment. The antibody response to king crab antigens was examined in sera from the subgroups and another (unrelated) control group. Extracts of crab meat, shell, and processing dust were used for skin testing and precipitin detection. FEV1, FVC, and MEFR decreased during the day in two crab processors, and precipitins were evident in sera from nine, but findings were normal in the fish packers. Crab meat elicited the strongest response, with multiple precipitin bands in some cases. Control sera showed no reaction. There was correlation between serology, results of skin tests, and symptoms. It is concluded that the inhalation of aerosolized crab antigen(s) may cause respiratory symptoms and can cause immunologic effects similar to those caused by other occupational respiratory allergens. We recommend preplacement and periodic medical examination of workers in crab-processing plants, improved ventilation in processing areas, and programs to discourage smoking.

Adolescent↗

Occurrence and significance of precipitating antibodies against thermophilic actinomycetes in the sera of dairy herd workers, Nangali, Delhi.

The study was prompted by the lack of information on the role of thermophilic actinomycetes in hypersensitivity pneumonitis in India. It reports the occurrence of precipitating antibodies against clinically important thermophilic actinomycetes in the sera of a population sample of dairy herd workers, Nangali, Delhi. Of 112 workers investigated, 28 (25%) showed precipitins against Faenia rectivirgula, 4 (3.2%) against Saccharomonospora viridis, 2 against Thermoactinomyces thalpophilus and one each against T. vulgaris and T. sacchari. The results of enzyme-linked immunosorbent assay (ELISA) indicated that IgG antibody activity against F. rectivirgula was significantly higher in the symptomatic group than in the asymptomatic group (p less than 0.05) of workers and the controls (p less than 0.01). Significant difference in F. rectivirgula IgG activity was also obtained between the precipitin-positive symptomatic group and the precipitin-positive asymptomatic group (p less than 0.05). In strong contrast, the IgG antibody activity against T. thalpophilus was found to be uniformly low. A limited aeromicrobiological sampling of the dairy farm revealed S. viridis (55.8%) to be the commonest species followed by T. vulgaris (19.2%), T. thalpophilus (18.5%), F. rectivirgula (5%) and T. sacchari (1.5%). On the basis of suggestive clinical and laboratory findings, farmer's lung disease was suspected in four dairy herd workers. A comprehensive clinical evaluation including pulmonary function studies on the dairy herd workers and their long-term follow-up is indicated to determine the extent of respiratory morbidity caused by F. rectivirgula, S. viridis, T. thalpophilus, T. sacchari and T. vulgaris in India.

Adult↗

Thermophilic actinomycetes in cane sugar mills: an aeromicrobiologic and seroepidemiologic study.

Aerial prevalence of clinically important thermophilic actinomycetes and occurrence of precipitating antibodies against them in sera of 153 exposed workers have been reported. The study was carried out in two cane sugar mills namely, the Upper Doab Sugar Mills and the Ramala Sugar Mills, located in north-west India. In both the sugar mills, T. sacchari was the predominant species, it accounted for 55.1% and 50.3% of the total population of thermophilic actinomycetes, followed by T. vulgaris (19.7% and 23.7%), T. thalpophilus (21.1% and 17.1%), Saccharomonospora viridis (3.4% and 5.0%) and Saccharopolyspora rectivirgula (Faenia rectivirgula) (0.7% and 3.9%), respectively. Precipitating antibodies against thermophilic actinomycetes were demonstrable in 34 (22.2%) workers; T. sacchari alone accounted for 20 of the positive precipitin reactions, followed by S. rectivirgula in 10. The mean absorbance values for IgG antibody activity against T. sacchari as well as S. rectivirgula were found to be elevated significantly in the symptomatic workers than in the asymptomatic workers (p < 0.05) or unexposed controls (p < 0.001). However, the difference in IgG antibody activity was insignificant between precipitin-positive symptomatic workers and precipitin-positive asymptomatic workers. The results indicate that clinically important thermophilic actinomycetes are widely prevalent in cane sugar mills, and T. sacchari and S. rectivirgula are the major species involved in the sensitization of the bagasse workers in India.

Actinomycetales↗

Detection of complement activation by counterimmunoelectrophoresis (CIE).

Counterimmunoelectrophoresis (CIE) was used as a method of detecting activation of the third component of the complement system (C3). Highly purified C3, normal human serum (NHS), EDTA-treated plasma and serum activated with aggregated human immunoglobulin (agg-IgG) or inulin were used as sources of C3 and/or C3 split products. Activation of the alternative pathway of complement was assayed in the presence of EGTA (10 mM) and MgCl2 (0.3 mM), conditions which block activation of the classical pathway. When purified native C3, fresh NHS and fresh EDTA-plasma were tested in CIE against either antisera to whole C3 or to C3 split products, only one precipitin line was found, which was identified as native C3. However, when serum activated with agg-IgG or inulin were tested against the same reagents, two precipitin lines were seen. The first, with more cathodal mobility was identical to that of native C3. The second line had a more anodal mobility, was distinctly separated from the first and contained C3c and C3d as shown immunochemically with specific antisera. Native C3 and split products of C3 were identified by this CIE method in patients showing evidence of activated complement by having subnormal total complement (CH50) levels. When C3 split products were identified, the C3c-C3d precipitin line could always be distinguished from native C3 by its different electrophoretic mobility, even when C3 concentrations in serum varied from 0.25 mg/ml to 1.5 mg/ml. The sensitivity of CIE was compared to that of CH50 by asssaying at different time intervals after agg-IgG was added to fresh NHS. C3c-C3d split products were detected by CIE before any fall in CH50 and at all times when a significant decrease in CH50 was present. This study shows that the CIE technique is a highly sensitive, specific and rapid method for detecting activation of the complement system via classical or alternative pathways in human disease.

Complement C3↗

Evaluation of polyethylene glycol's suitability for quantitative determination of non-precipitating antibody.

Polyethylene glycol (PEG) has been used extensively in the quantitative precipitin reaction and for the determination of soluble immune complexes. It has now been found that the optimum concentration of PEG for precipitation of non-precipitating antibodies in the quantitative precipitin reaction varies with the dilution of antisera. Immune precipitates obtained with PEG were examined for their protein content by polyacrylamide gel electrophoresis to detect non-specific precipitation of serum proteins. Determination of non-precipitating antibodies in sera of goats and pigs immunized with chicken egg-white lysozyme by the quantitative precipitin reaction in the presence of PEG, yielded lower values than obtained by immunoabsorbents. Care should be exercised in interpreting results when PEG is used to enhance precipitation.

Animals↗

Immunologic response to Faenia rectivirgula (Micropolyspora faeni) in a dairy farm family.

In the present study, cellular and humoral responses to Faenia rectivirgula antigens were evaluated in seven subjects, members of a family who lived and worked on a dairy farm. Four subjects had clinical features of hypersensitivity pneumonitis after exposure to moldy hay. The other three subjects had no clinical disease in spite of similar exposure. Although serum precipitins were found in most subjects, a biotin-avidin-linked immunosorbent assay revealed high levels of F. rectivirgula-specific antibodies only in the symptomatic subjects. In addition, numerous precipitin arcs were present in the sera of the symptomatic but not the asymptomatic subjects by antigen-antibody crossed immunoelectrophoresis. No clear distinction between symptomatic and asymptomatic subjects could be made on the basis of lymphocyte phenotype studies, and antigen-induced lymphocyte transformation was not detected in any subjects. The results indicate that F. rectivirgula-specific antibody levels as detected by biotin-avidin-linked immunosorbent assay and by the presence of precipitin arcs in crossed immunoelectrophoresis may differentiate symptomatic and asymptomatic farmers.

Actinomycetales Infections↗

Snailine: a possible diagnostic reagent from a common marine snail, the southern periwinkle, Littorina angulifera.

A substance which strongly precipitates human serum proteins is released into the environment by the southern periwinkle, Littorina angulifera. Two-dimensional crossed immunoelectrophoresis revealed that the snail precipitin reacts with a number of human serum proteins, including 11 not detected by mammalian antiserum. The precipitin is readily collected in saline solution, which then is referred to as snailine, a potentially useful diagnostic reagent. Precipitins released into the environment by marine species may represent a little-known external immunologic system.

Animals↗

Analysis of the specificity of natural human antibody reactive to Actinomyces.

The specificity of a frequently-occurring precipitin response to soluble antigens from cell-walls and culture filtrates of A. viscosus ATCC 19246 was examined. After precipitation with isopropanol (50-75% v/v), antigen fractions of different charge and molecular weight were isolated by ion exchange and gel filtration. When heated in mineral acid or alkali above 0.15 M, each of the purified antigens lost precipitating activity, but now inhibited the precipitin reaction between serum and exogenous unheated antigen. The inhibitor was isolated over Biogel P30 and characterized as a peptide fragment (mol. wt about 2 kd) containing approximately 50 moles of ornithine and 6-12 moles, respectively, of aspartate, serine, threonine, glutamate, glycine, alanine and histidine per 100 moles amino acids. The inhibitor was totally destroyed by heating for 1.0 hr in 2.0 M HCl. Variability in the number of fragments and differences in the non-antigenic portions probably accounted for the complexity of the antigens. Ornithine, putrescine, N-acetyl putrescine and various sugars had little or no effect on the precipitin reaction with intact antigen at high concentrations (200 mM), whereas the fragment inhibited completely at 0.4 mM. This indicates that neither ornithine nor its side-chain amides are exclusively recognized by antibody. However, ornithine may be part of a larger sequence and/or important in forming the configuration recognized by the human antibodies.

Actinomyces↗

Factors affecting the use of immunoosmophoresis for the detection of two insect riboviruses.

Some of the factors affecting the formation of precipitin lines during immunoosmophoresis were investigated using two unrelated insect riboviruses, Flock House virus (FHV) and cricket paralysis virus (CrPV). Precipitin lines formed in under 90 min. Concentrations of 200-400 ng/ml of FHV were routinely detected but occasionally the end-point was as low as 50 ng/ml. With CrPV, 1500 ng/ml was the routine detectable level. The sensitivity of the assay was largely unaffected by the presence of insect homogenate. Maximum detection of virus was obtained when the antigens and antibodies were at optimal proportion and excess of either reagent resulted in the blurring of precipitin lines. Immunoosmophoresis proved to be a rapid and inexpensive method of detecting negatively charged viruses in crude insect extracts and can, in some cases, have a sensitivity approaching that of more sophisticated serological techniques.

Antibodies, Viral↗

Precipitation of animal plasma proteins by puff-adder venom.

1. Plasma and serum samples obtained from various animals never previously exposed to snakes or snake venom were diffused against different concentrations of puff-adder, Bitis arietans, venom using the double immunodiffusion technique. 2. Depending upon venom concentration, two precipitin arcs could be produced in the case of all plasma samples used. No serum samples showed any arcs except pigeon serum, where one precipitin line was observed. 3. By altering the concentration of snake venom between 1% and 10% when immunodiffusing against plasma a change in position of the precipitin lines was observed and also the disappearance of one or both of the two bands at higher concentrations. This indicates that the arcs observed are in all probability due to precipitation of plasma protein fractions. 4. Previous results indicated that one of the two bands observed when diffusing venom against plasma was due to the precipitation of fibrinogen. By diffusing snake venom against heparin we have now shown that the second band involves this molecule and is not due to another coagulation factor as was suggested previously.

Animals↗

Mutant analysis of glyceraldehyde 3-phosphate dehydrogenase in Escherichia coli.

NAD(+)-specific glyceraldehyde 3-phosphate dehydrogenase (EC 1.2.1.12) from Escherichia coli was purified to homogeneity by a relatively simple procedure involving affinity chromatography on agarose-hexane-NAD(+) and repeated crystallization. Rabbit antiserum directed against this protein produced one precipitin line in double-diffusion studies against the pure enzyme, and two lines against crude extracts of wild-type E. coli strains. Both precipitin lines represent the interaction of antibody with determinants specific for glyceraldehyde 3-phosphate dehydrogenase. Nine independent mutants of E. coli lacking glyceraldehyde 3-phosphate dehydrogenase activity all possessed some antigenic cross-reacting material to the wild-type enzyme. The mutants could be divided into three groups on the basis of the types and amounts of precipitin lines observed in double-diffusion experiments; one group formed little cross-reacting material. The cross-reacting material in crude cell-free extracts of several of the mutant strains were also tested for alterations in their affinity for NAD(+) and their phosphorylative activity. The cumulative data indicate that the protein in several of the mutant strains is severely altered, and thus that glyceraldehyde 3-phosphate dehydrogenase is unlikely to have an essential, non-catalytic function such as buffering nicotinamide nucleotide or glycolytic-intermediate concentrations. Others of the mutants tested have cross-reacting material which behaved like the wild-type enzyme for the several parameters studied; the proteins from these strains, once purified, might serve as useful analogues of the wild-type enzyme.

Adenosine Triphosphate↗