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Effects of penicillin and lysozyme on the immunofluorescent and precipitin reactivity of group D streptococci.

Damage to the cell wall by growth in the presence of penicillin or by treatment with lysozyme enhanced the immunofluorescent (fluorescent antibody, FA) reactivity to group D streptococci. The optimum concentration and time of treatment with lysozyme varied inversely with the initial FA reactivity of the strain. Speciation of the organisms by a series of biochemical and physiologic tests suggested that the differences in initial FA reactivity were species-related. Thus, S. faecalis strains were the most FA-reactive and most sensitive to lysozyme. S. faecium strains were less FA-reactive and lysozyme-sensitive. S. bovis strains proved to be least FA-sensitive and were most resistant to lysozyme. Treatment with lysozyme was also effective in preparing extracts of group D antigen from all three species for Lancefield grouping by the precipitin test. The lysozyme extracts, moreover, produced much stronger reactions than those made from comparable volumes of cells by the methods of Lancefield or of Rantz and Randall.

Antibodies, Heterophile↗

The reliability and rapidity of the coagglutination technic and its comparison with precipitin technic in the grouping of streptococci.

Three methods of the grouping of 170 strains of beta-hemolytic streptococci belonging to Groups A, B, C, F, and G by capillary and agar-gel precipitation using Lancefield extract and by coagglutination of antibody-coated protein A-containing staphylococci were compared. Capillary and agar-gel precipitin technics correctly grouped all 170 strains, with no cross-reaction. One hundred sixty-nine out of the 170 strains were also correctly grouped by the coagglutination technic, and the one strain with a cross-reaction was correctly grouped after blood--agar subculture. Although 20 of the 170 strains showed minor cross-reactions by the coagglutination technic, the specific groups were easily and unquestionably detected, and the minor cross-reactions were easily overcome. A rapid method of grouping by coagglutination technic using 4--6-hour broth culture, done on 75 strains, showed that 73 strains could be correctly grouped by the rapid method and two after overnight incubation. Thus, the coagglutination technic of grouping was found to be easy, reliable, and economical, and could be adopted in any routine diagnostic laboratory as a rapid grouping procedure.

Agglutination Tests↗

Precipitins to dietary proteins in atopic eczema.

Precipitating antibodies to foods have been assayed in three groups of patients with atopy. Forty-five per cent of patients with atopic eczema and IgE-mediated food allergy had precipitins to foods in their serum compared with only 15% of patients with atopic eczema without evidence of food allergy, and 16% of patients with atopic asthma and/or rhinitis. It is likely that this results from increased intestinal permeability in the group with eczema and food allergy.

Adult↗

Comparison of a microneutralisation test with ELISA and precipitin tests for detection of antibodies to infectious bronchitis virus in chickens.

A microneutralisation test for infectious bronchitis virus using virus antigens available in Australia, cell culture medium containing low concentrations of serum and an elevated incubation temperature is described. The technique was economical on reagents and of comparable sensitivity to the enzyme-linked immunosorbent assay (ELISA). The value of the microneutralisation, ELISA and precipitin tests in assessing the serological response of a flock of commercial chickens to vaccine and natural virus challenge was determined.

Animals↗

[A case of schistosomiasis suspected by circumoval precipitin test and diagnosed by rectal biopsy].

A forty-year-old female from Brazil was admitted to Teikyo Hospital because of easy fatigability, fullness of the abdomen and left hyochondralgia. She was anxious about Schistosoma mansoni infection, because three of her relatives died of the infection. Physical examinations revealed a tenderness at the left hypochondrium. Laboratory data showed no abnormal finding. No egg of S. mansoni was found in the stool. A circumoval precipitin test (COPT) with the serum showed a deposite around the egg. Enzyme-linked immunosorbent assay (ELISA) revealed the presence of antibody against S. mansoni in the serum. A colonoscopy showed no abnormal finding macroscopically. The rectal biopsy showed the existence of mild procitis. The diagnosis was made by finding the characteristic lateral-spined eggs in the biopsy specimens from the rectum. Treatment of 3 g of prazicantel per day for three days was started. She complained of mild nausea at the first dosing. A month later, another three-day-treatment was given. In the case where there are no eggs found in the stool, COPT and ELISA are usefull in detecting the disease, and colonoscopy is recommended in diagnosing the disease.

Adult↗

Agar-gel precipitin-inhibition technique for plague antibody determinations.

An application of the agar-gel precipitin-inhibition technique we described previously can be used to detect plague antibodies in human and animal sera after a series of plague vaccine inoculations or after exposure to Pasteurella pestis. Determination of the minimal reacting concentrations of the plague antigen and antibody reagents, methods for combining reagents, and length of incubation periods are discussed.

Animals↗

Agar-gel precipitin-inhibition technique for histoplasmosis antibody determinations.

The agar-gel precipitin-inhibition technique has been modified to detect antibodies of Histoplasma capsulatum in sera from human clinical cases and experimental animals infected with this organism. By use of this modified technique, the histoplasmosis can be detected more consistently and reliably than with the direct agar-gel diffusion test, and titers are comparable to those attained by the complement-fixation serological technique.

Animals↗

Quantitative aspects of the M protein capillary precipitin test.

A capillary procedure for quantitatively determining M protein is described. Capillaries were filled with measured amounts of serum and streptococcal extract. The capillaries were incubated, and then centrifuged to pack the precipitates. The relative sizes of the precipates were compared by a determination of the weights of their paper images (obtained by reflection from a microscope). Meaningful dilution curves were determined by this method. Variations of pH from 6 to 8 had little effect on the M protein precipitin test, and the test was not seriously affected by variations of the NaCl concentration from 0.85 to 4.67%. The addition of divalent ions (Ca(++) and Mg(++)) did not influence the results. This test can be used to make quantitative comparisons of M protein preparations and to titrate type-specific antisera.

Bacterial Proteins↗

Localization of the tube precipitin and complement fixation antigens of Coccidioides immitis by immunoelectron microscopy with murine monoclonal antibodies.

The cellular localization of the tube precipitin (TP) and complement fixation (CF) antigens of Coccidioides immitis was examined by immunoelectron microscopy with murine immunoglobulin G1 monoclonal antibodies directed against the TP and CF antigens, respectively. Immunoelectron microscopic analyses of saprobic- and parasitic-phase cells showed that the TP antigen is present at a high concentration within the inner cell wall layer and along the plasma membrane. The antigen was also detected, at a lesser concentration, within cytoplasmic vacuoles. In contrast to the predominant localization of the TP antigen in the cell walls, the CF antigen residues primarily within the cytoplasm, where it appears to be dispersed throughout the cytoplasm rather than associated with a specific cytoplasmic organelle. A sparse amount of the CF antigen within the inner cell walls was also demonstrable. The localization of the TP and CF antigens throughout the morphogenetic phases of C. immitis has important implications in antigen production and in analyses of host response in coccidioidomycosis.

Animals↗

Cloning and expression of the gene which encodes a tube precipitin antigen and wall-associated beta-glucosidase of Coccidioides immitis.

We report the structure and expression of the Coccidioides immitis BGL2 gene which encodes a previously characterized 120-kDa glycoprotein of this fungal respiratory pathogen. The glycoprotein is recognized by immunoglobulin M tube precipitin (TP) antibody present in sera of patients with coccidioidomycosis, a reaction which has been used for serodiagnosis of early coccidioidal infection. The deduced amino acid sequence of BGL2 shows 12 potential N glycosylation sites and numerous serine-threonine-rich regions which could function as sites for O glycosylation. In addition, the protein sequence includes a domain which is characteristic of family 3 glycosyl hydrolases. Earlier biochemical studies of the purified 120-kDa TP antigen revealed that it functions as a beta-glucosidase (EC 3.2.1.21). Its amino acid sequence shows high homology to several other reported fungal beta-glucosidases which are members of the family 3 glycosyl hydrolases. Results of previous studies have also suggested that the 120-kDa beta-glucosidase participates in wall modification during differentiation of the parasitic cells (spherules) of C. immitis. In this study we showed that expression of the BGL2 gene is elevated during isotropic growth of spherules and the peak of wall-associated BGL2 enzyme activity correlates with this same phase of parasitic cell differentiation. These data support our hypothesis that the 120-kDa beta-glucosidase plays a morphogenetic role in the parasitic cycle of C. immitis.

Amino Acid Sequence↗

Purification and amino-terminal sequence analysis of the complement-fixing and precipitin antigens from Coccidioides immitis.

Two proteins (21 and 48 kilodaltons) purified from endospore-spherule culture filtrates of Coccidioides immitis are identified as precipitin and complement-fixing antigens, respectively. To allow specific structural comparison to antigens identified by other investigators and as a first step to eventual serodiagnostic antigen production by recombinant DNA technology, amino-terminal amino acid sequences were determined for these antigens.

Amino Acid Sequence↗

Detection of neonatal calf diarrhea virus, infant reovirus-like diarrhea virus, and a coronavirus using the fluorescent virus precipitin test.

Thirty-four calf and five infant fecal specimens were tested for the neonatal calf diarrhea virus (NCDV) and for the reovirus-like infantile diarrhea agent; respectively. The procedures used were the fluorescent virus precipitin test and immune electron microscopy. Fourteen of the calf stools contained detectable NCDV, and four of the five infant stools contained the reovirus-like human agent. Infectious NCDV was detected in four of the 34 calf fecal specimens when Madin-Darby bovine kidney cell cultures that had been inoculated with supernatant fluids from stool suspensions were stained with fluorescent antibody. The 20 calf stools that did not have detectable virus were examined for the bovine corona diarrhea virus. Coronavirus was found in two of these specimens.

Animals↗

An improved test for Haemophilus influenzae precipitins in the serum of patients with chronic respiratory disease.

The detection of antibacterial precipitins in the serum of patients with chronic lower respiratory infections has been shown to be of great value in the assessment of pathogenicity of the corresponding bacterial species in the sputum. The test used hitherto, however, is time-consuming and cumbersome owing to the need to distinguish, by immunoelectrophoresis, between antibodies specific to the organism in question and those which react with antigens common to various Gram-negative species. A method has now been devised for the preparation of an extract of Haemophilus influenzae containing species-specific antigens only. Use of this extract obviates the need for immuno-electrophoresis and improves the sensitivity of the test.

Antigens, Bacterial↗

Bacterial precipitins and their immunoglobulin class in atopic asthma, non-atopic asthma, and chronic bronchitis.

In a study of groups of patients with atopic (extrinsic) asthma, non-atopic (intrinsic) asthma, and chronic bronchitis, no difference could be detected in the numbers having precipitating antibodies against species specific antigens from Staphylococcus aureus or Streptococcus pneumoniae compared to suitably matched control subjects. Precipitating antibodies against species specific antigens from Haemophilus influenzae, demonstrated in this investigation by double diffusion in agar gel, were found much more frequently in patients with chronic mucopurulent or obstructive bronchitis (50%) than in either asthmatic subjects (6%) or normal controls (6%) (P = less than 0.0005). While the precipitating antibody demonstrated in these patients against the extracts of Str. pneumoniae and Staph. aureus was in the IgG class alone, IgM and IgA antibody were detected against the species specific but not the non-species specific antigens of H. influenzae. These results underline the importance of H. influenzae as an infecting agent in chronic bronchitis and suggest that the finding of precipitins against the species specific H1 and H2 antigens of this bacterium denotes infection either concurrently or in the recent past. There is no evidence to suggest from this study that infection with Staph. aureus, Str. pneumoniae or H. influenzae is any more common in asthmatics as a group compared to controls or between patients with the non-atopic (intrinsic) and atopic (extrinsic) form of the disease.

Adolescent↗

Application of 125I radioimmunoassay to measure inhibition of precipitin reactions using carbohydrate-specific antibodies.

Antibodies raised to an artificial antigen with beta-D-galactopyranosyl groups as antigenic determinants were purified using an immunoadsorbent prepared from the hapten involved in the synthesis of the antigen. In order to study the specificity of these antibodies, 125I radiolabelling of either the artificial antigen or the antibody was used in the study of inhibitions of the precipitin reaction. The method, involving labelling of the artificial antigen and counting radioactivity in the supernatant, was found to be more accurate and faster than the usual methods based on measuring the amount of protein precipitated by chemical or spectroscopic methods.

Antibodies↗

Unusual precipitins in pathological human sera.

In conducting double diffusion gel precipitation tests, unexpected, strong precipitation reactions were noticed between a serum originating from a renal graft recipient and many pathological human sera. The highest frequency of positive reactions were produced by sera of patients with infectious mononucleosis (83%), chronic Epstein-Barr virus infections (72%), rheumatoid arthritis (57%), lepromatous leprosy (57%), and AIDS (44%). The precipitin in these pathological sera was identified as an antibody of IgM variety and the precipitinogen in the transplantation serum was shown to be a thermostable component with beta-globulin mobility. No explanation of the nature of reactions observed can be given at present.

Acquired Immunodeficiency Syndrome↗

An immunologic precipitin system between soluble nucleoprotein and serum antibody in systemic lupus erythematosus.

Double diffusion in agarose was employed for the characterization of a soluble nucleoprotein antigen that gave precipitin reactions with sera from patients with systemic lupus erythematosus. The soluble antigen that was isolated from calf thymus nuclei was demonstrated by enzyme degradation and ultracentrifugation studies, and by immunologic analysis, to be a complex of deoxyribonucleic acid and a moiety susceptible to proteolytic digestion. Antibody to soluble nucleoprotein did not react with the DNA portion of the complex released after proteolytic digestion or with purified calf thymus DNA. Immunologic reaction of identity was obtained between the soluble nucleoprotein antigen and synthesized DNA-histone complex, suggesting that the protein moiety of soluble nucleoprotein might in part be composed of histone. Antibody to soluble nucleoprotein was present in 51% of systemic lupus erythematosus sera examined and was more common than antibody to deoxyribonucleic acid.

Antibodies↗

Comparison of agar-gel precipitin responses among strains of fowl adenovirus using antigens prepared from chorioallantoic membranes and chicken kidney cell cultures.

Agar-gel precipitin responses obtained for serologically different strains of fowl adenovirus (FAV) in tests using antigens prepared from FAV-infected chorioallantoic membranes (CAM antigen) and chicken kidney cell cultures (CKC antigen) were compared. Findings showed that both types of antigens exhibited less sensitivity to heterologous than to homologous antisera and that quantitative differences in sensitivity were present between serotypes. CAM antigens were more sensitive than CKC antigens to heterologous antisera. Polyvalent CAM antigens containing 2 or 3 antigens increased sensitivity in testing of field serum samples, resulting in a higher rate of detection.

Adenoviridae Infections↗