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[Immunoglobulins in serum and seminal fluid in patients with sperm agglutination].

Serum immunoglobulins and immunoglobulins in the seminal fluid were determined in 32 men with normospermia without agglutination and in 37 men with normospermia with agglutination. In the seminal fluid also secretory IgA and the secretory component were recorded. The values of serum immunoglobulins were more or less the same. So were the IgG values in the seminal plasma of both groups. IgA was found more frequently in the seminal plasma of patients with agglutination. IgM was not found at all. Secretory IgA and the secretory component were for the most part found in the seminal plasma of patients with normospermia and agglutination. The finding of secretory IgA and the secretory component gives an insight into the local synthesis of sperma-antibodies.

Humans↗

[Introduction of an additional H-agglutinating test antigen for the differentiation of specific positive reactions in pullorum disease-fowl typhoid in poultry experimentally infected with Salmonella gallinarum-pullorum and Salmonella enteritidis].

Explored were the possibilities to differentiate the specific positive reactions in case of pullorum disease in experimentally infected (Salmonella gallinarum-pullorum and Salmonella enteritidis) birds with the use of a typhoid test antigen and two H test antigens, obtained by the routinely employed method with formalin from Salmonella enteritidis and Salmonella adeoyo. It was demonstrated that the H-agglutinating antibodies persisted in the peripheral blood of the experimentally infected birds for at least 30 days (as long as the test lasted). The H test antigen of S. enteritidis proved unsuitable to detect the H-agglutinating antibodies only as it retained to a large extent the O antigens. By means of the S. adeoyo H test antigen only the H-agglutinating antibodies in the peripheral blood of S. enteritidis-infected birds could be quickly and precisely demonstrated. A combined serologic examination of serum with the thyphoid test antigen and the S. adeoyo test antigen could be carried out to differentiate the specific positive reactions for establishing pullorum disease from the concomitant agglutination reactions observed in cases of experimental salmonellosis in birds caused by S. enteritidis.

Agglutination Tests↗

Unrelatedness between agglutinations of bacteria and the presence of anti-polysaccharides in sera of Salmonellae from groups B and D.

Rabbits hyperimmunized with two strains of S. paratyphi B provided sera with high agglutinating titers, although the sera were deprived of antipolysaccharide antibodies. However, the polysaccharides of both strains of S. paratyphi B precipitated against anti S. typhimurium sera in which antipolysaccharide antibodies were induced. Antisera obtained with three S. enteritidis strains showed a comparable unrelatedness between the agglutinating titers and the presence of antipolysaccharide antibodies in the corresponding sera. One of the strains, repeatedly used for immunization, never induced antipolysaccharide antibodies, while the agglutinating titers of the sera were high; the polysaccharide of this strain precipitated strongly against anti-Salmonella typhi O 901 sera and against the antisera of the other S. enteritidis strains in which antipolysaccharide antibodies were induced. According to these results, there is no apparent relationship between agglutinations of bacteria and the presence of antipolysaccharide antibodies in the corresponding sera. Heated proteins, isolated from all the strains after previous exhaustive extraction at 37 degrees C, showed strong serological precipitations.

Agglutination Tests↗

Serologic studies on porcine strains of Haemophilus parahaemolyticus (pleuropneumoniae): agglutination reactions.

Fifteen strains of Haemophilus parahaemolyticus (pleuropneumoniae) represented by 6 American isolates, 6 Swedish isolates, and 3 reference strains of Nicolet's serotype 1, 2 and 3, were used in serologic studies by agglutination and agglutinin-adsorption tests. By whole cell-agglutination tests in rabbit antiserums, 3 additional serotypes, 4, 5, and 6, were identified. All strains had strong serotype-specific agglutinating properties. Occasional weak cross reactions could be eliminated by appropriate adsorptions without effect upon type-specific reactivity. The Swedish isolates were assigned to serotypes 2, 3, 4, and 6, and the American isolates, to serotypes 4 and 5. All European isolates were distinct from 5 of the 6 American strains. An American culture isolated from a steer and another from a lamb were identical in their agglutination reactions with the porcine isolates of serotype 5. The serotyping of isolated strains is important in the epizootiologic and immunologic studies of H parahaemolyticus infections.

Adsorption↗

[The biological properties of adsorbed and nonadsorbed OH-agglutinating sera for the identification of Rahnella aquatilis bacteria].

The paper presents the production technology of rabbit hyperimmune adsorbed and unadsorbed OH-agglutinating sera for Rahnella aquatilis bacteria identification. Results are reported for such biological characteristics of the new preparations as their specificity and agglutination activity (titer). It is shown that cultures R. aquatilis ATCC 33989 and ATCC 33071 possess marked immunogenic properties and E.cloaceae 1903 strain has good absorptional ones, that enables one to employ them for production of agglutinating sera. It is concluded that new adsorbed and unadsorbed OH-agglutinating sera may be used for microbiological diagnosis of diseases caused by R. aquatilis.

Adsorption↗

[Meaning of serotype Patoc (biflexa complex) for the diagnosis of leptospirosis by microscopic agglutination test (author's transl)].

Agglutination with serotype patoc (Patoc 1) was found in 72 of 125 cases of leptospirosis. Patoc-agglutination occured frequently in leptospirosis icterohaemorrhagiae, less frequently in leptospirosis grippotyphosa and rarely in leptospirosis tarassovi. 53 cases of leptospirosis were not diagnosed when using Patoc 1 as single antigen. So we cannot recommend to use serotype patoc as the sole antigen for microscopic agglutination test. We observed 1 case in which the reaction with Patoc 1 happened earlier than the reaction with the pathogen serotypes. For this reason the battery of antigens for carrying out microscopic agglutination test should include serotype patoc, too.

Agglutination Tests↗

Interfacial instability and the agglutination of erythrocytes by polylysine.

Human erythrocytes have been exposed to polylysine of molecular weight range 4 to 220 kDa and concentration range 0.5 to 2,000 micrograms/ml at 37 degrees C. Threshold concentrations for cell agglutination by the polycation have been determined for the samples of different molecular weight. Light and electron micrographs show that, in the erythrocyte agglutinates, cell-cell contact is generally made only at discrete, spatially periodic, regions which are distributed over a significant part of the cell surface. The average spacing between contact regions is 0.83 micron. The cell membrane has a wavy profile between contact regions. Agglutination occurs only in cell samples whose electrophoretic mobility is significantly altered by polylysine and, in agreement with a previous report, occurs even when the electrophoretic mobility reaches high positive values. The electrophoretic mobility data implies that agglutination requires some protrusion of polylysine from the cell glycocalyx. We discuss how a resulting net attractive intercellular force could act to destabilize the aqueous layer between two cells, allowing surface wave growth which results in spatially periodic contact regions. Examples of situations where cell and membrane contact might by explained by the general concept of interfacial instability are discussed.

Erythrocytes↗

Changes in surface architecture during murine erythroleukemia cell differentiation as detected by lectin binding and agglutination.

Cell surface alterations occurred during murine erythroleukemia cell (clone 745) differentiation that were detected by both agglutination and lectin binding. Agglutination of erythroleukemia cells was produced by wheat germ agglutinin; whereas, concanavalin A, Ricin, soybean agglutinin and fucose-binding protein were either ineffective or much less efficacious. Treatment of leukemia cells with the inducer of erythroid differentiation dimethylsulfoxide (DMSO) caused a progressive accumulation of hemoglobin-containing cells in culture and a decrease in the rate of agglutination by wheat germ agglutinin, which began at 24 h after exposure to the polar solvent, reached a nadir at 48 h, and remained essentially constant thereafter. The binding of radioactive wheat germ agglutinin by untreated control erythroleukemia cells increased with time in culture, reaching a maximum value at 48 h, and decreased progressively thereafter. Although an increase in 3H-labeled wheat germ agglutinin binding also occurred in DMSO-treated cells, the level bound was significantly lower than that observed in control cells at 24-96 h. The treatment of erythroleukemia cells with various concentrations of DMSO resulted in a decrease in the number of wheat germ agglutinin receptor sites. Other inducers of differentiation (i.e., dimethylformamide, bis(acetyl)diaminopentane) also inhibited the rate of wheat germ agglutinin-induced agglutination of erythroleukemia cells while, in contrast, the inducer tetramethylurea did not. These studies indicate that membrane changes occur during differentiation and suggest that there may be more than one mechanism involved in the initiation of maturation which ultimately leads to the common pathway of erythroid development.

Animals↗

Agglutination of mouse erythrocytes by binding of non-choline phospholipids to a 70 000-Dalton protein.

The structure of some phospholipids that cause agglutination of mouse erythrocytes has been studied. Haemagglutination is a property of non-choline-containing phospholipids; the phosphate group is essential and unsaturated fatty acids optimal. A protein of Mr 70 000 was isolated from mouse erythrocyte membranes which completely inhibited phospholipid-mediated erythrocyte agglutination. It is proposed that this protein is the phospholipid binding site on mouse erythrocytes and the ligand for the human B-lymphocyte receptor for mouse erythrocytes. Preliminary investigations suggest that a similar inhibitor of phospholipid-mediated agglutination is found in serum. Agglutination of mouse erythrocytes by phospholipid and specific inhibition by the 70 kDa membrane protein constitute a simple system for studying the interaction of phospholipid with protein.

Animals↗

Particle counting immunoassay (PACIA). II. Automated determination of circulating immune complexes by inhibition of the agglutinating activity of rheumatoid sera.

Antigen--antibody complexes were detected in patients' sera by inhibition of the agglutinating activity of rheumatoid sera toward IgG coated particles (latex). Precision, sensitivity (1--10 microgram/ml equivalents of heat-aggregated IgG), and reproducibility (maximum coefficient of variation of 11%) were obtained by measuring agglutination with an instrument counting the residual free particles. Automation allowed testing of 20 to 40 samples per hour. The inhibitory activity of spontańeously agglutinating sera was determined after inactivating endogenous rheumatoid factor by reduction with dithiothreitol. Non-aggregated IgG did not significantly interfere. The agglutinating activity of 6 rheumatoid sera was tested after incubation with the various immunoglobulin classes and subclasses polymerized by coupling to agarose, and all were found to be readily absorbed by IgG1, but poorly by IgG3, IgA1 and IgM. Reactivity with IgG2, IgG4 and IgA2 clearly differed for different rheumatoid sera. Among 70 sera from blood donors, 7 had abnormally high inhibitory activity. Six of these had also an abnormal protein profile, suggesting existence of latent disease. High inhibitory activity in 15 sera out of 18 from patients with systemic lupus erythematosus, and in 23 sera out of 46 from patients with breast cancer suggested that the rheumatoid factor inhibition test has a discriminatory capacity comparable with that of more sophisticated techniques requiring radioisotopes and/or cellular material.

Antigen-Antibody Complex↗

A spectrophotometric method for evaluating a latex agglutination assay of Salmonella typhi lipopolysaccharide.

A spectrophotometer set at a wavelength of 400 nm was used to read reaction mixtures containing a 0.01% suspension of antibody-sensitized latex particles and different amounts of soluble antigen, after incubation in tubes for 30 min. The antigen used was Salmonella typhi lipopolysaccharide, and the antibody was an O-9-specific monoclonal antibody. Agglutination was indicated by a fall in the turbidimetric measurement compared to control, unagglutinated latex. It was observed that agglutination increased with increasing concentrations of antigen to a maximum at 0.25-1.0 micrograms/ml, after which, the amount of agglutination decreased at a similar rate as far as 1 mg/ml of antigen, when no agglutination occurred at all. Thus, a bi-symmetrical curve was obtained, suggestive of a precipitation reaction. At the 'equivalence point', the turbidity of the reaction mixture compared to control fell from OD400 1.1 to OD400 0.3. A similar inhibition of reaction at 'antigen excess' was observed visually in the reaction mixtures. Conventional slide tests performed in parallel could also be inhibited, but at higher antigen levels. Inhibition could be achieved with a commercially available latex used for the detection of Neisseria meningitidis antigen.

Antigens, Bacterial↗

DNA hybridization and latex agglutination for detection of heat-labile- and shiga-like toxin-producing Escherichia coli in meat.

DNA-hybridization and latex-agglutination tests were used for screening of a group of Escherichia coli isolates for heat-labile enterotoxin (LT)- and shiga-like toxin (SLT1 or VT1) -producing strains, respectively. Strains tested originated from 162 meat samples (poultry, pigs and beef) chosen at random. Additionally LT- and SLT1-producing reference strains were tested. The DNA-hybridization technique allowed screening of large numbers of strains, whereas large scale testing of strains by latex agglutination was laborious. Of 800 E. coli strains tested by DNA hybridization none contained the gene encoding LT. Production of LT as tested by latex agglutination was not found. The gene encoding SLT1 was detected in 10 of the 800 isolates tested. None of these strains, however, showed cytotoxicity on Vero cells. Serotyping was done with sorbitol-negative E. coli strains, first by using the latex-agglutination test for O157 followed by complete serotyping. No E. coli of serogroup O157 were found. Therefore the results obtained also indicate that routine screening of E. coli isolated randomly from food for toxin production is not useful and should be limited to food-borne disease outbreaks with an etiology resembling an E. coli infection.

Animals↗

Detection of porcine rotavirus in stools by a latex agglutination test.

We developed a simple agglutination test for the detection of porcine rotavirus in stools from pigs with diarrhea. The virus was detected with high sensitivity and specificity by a slide agglutination test using latex particles coated with antibody against the porcine rotavirus strain OSU (LA-antiOSU). The agglutination of LA-antiOSU with OSU on a glass slide was evident macroscopically within 2 min. The sensitivity of this latex agglutination (LA) test was four times higher than that of the electron microscope method. The LA test is available for the rapid diagnosis of porcine rotavirus infections.

Animals↗

Sperm-agglutinating and -immobilizing antibody formation following vasectomy prevented with dexamethasone in cynomolgus monkeys.

Cynomolgus monkeys (Macaca fascicularis) were treated with 1.5 mg/kg dexamethasone (DEX) before (4 to 2 days) and after (0, 2, 4, and 7 days) vasectomy. Of the four monkeys treated with DEX, only one developed sperm antibody as measured by sperm-agglutinating and sperm-immobilizing assays. All six of the vasectomized monkeys not given DEX developed both agglutinating and immobilizing sperm antibodies. In this study, DEX given before and after vasectomy blocked sperm-agglutinating and -immobilizing antibody formation. We conclude that the major antigenic exposure to sperm responsible for sperm-agglutinating and -immobilizing antibody comes at the time of vasectomy.

Animals↗

Detection of Trypanosoma brucei, T. congolense and T. vivax infections in cattle, sheep and goats using latex agglutination.

A monoclonal antibody-based latex agglutination test for detection of circulating trypanosome antigens in animal serum was evaluated for the ability to detect natural T. brucei, T. congolense and T. vivax infections in cattle, sheep and goats in Ghana. The test detected antigens in 180/422 (42.7%) of cattle, 27/131 (20.6%) of sheep and 14/79 (17.7%) of the goats. By comparison, the microplate-based antigen-ELISA gave similar results (P > 0.01), detecting trypanosome antigens in 41.7% of the cattle, 19.8% of the sheep and 17.7% of the goats. Trypanosomes were demonstrated in the blood of 30 (7.2%) cattle, 7 (5.3%) sheep and 3 (3.8%) goats using the buffy coat technique (BCT). Of these, 26 cattle (86.7%), 6 sheep (85.7%) and all 3 goats (100%) were antigenaemic. The most prevalent single infection in all 3 animal species involved T. vivax, and the most common mixed infection involved all 3 trypanosome species in cattle and sheep. There was no mixed infection in goats. Compared with the antigen-ELISA, the sensitivity of the latex agglutination test was 98.3% in cattle and 100% in both sheep and goats, whilst the specificity was 97.2% in cattle, 99% in sheep and 100% in goats. False positivity with the latex agglutination test was 3.9% in cattle and 3.7% in sheep. There were no false-positive reactions with the test in goats. The latex agglutination assay promises to be ideal for testing small numbers of animals under field conditions.

Animals↗

Disruption of erythrocyte rosettes and agglutination of erythrocytes infected with Plasmodium falciparum by the sera of Papua New Guineans.

People living in areas endemic for Plasmodium falciparum develop humoral responses which may contribute to protection against clinical disease but the specificity of such protective antibody responses remains to be defined. Antibodies disrupting erythrocyte rosettes have been associated with protection against cerebral malaria, and antibodies agglutinating infected erythrocytes with reduced episodes of clinical disease. We have studied the capacity of serum from Papua New Guinean adults and children with a spectrum of malaria exposure, including children and adults at the time of clinical disease, to disrupt erythrocyte rosettes and cause agglutination of infected erythrocytes. Using a single parasite isolate, almost all sera from adults from highly endemic areas agglutinated infected erythrocytes, and the majority disrupted rosettes, in some cases at greater titres than hitherto described. There was a correlation between rosette disruption and agglutination in highly exposed adults. Rosette disrupting antibodies were equally frequent in children with cerebral and uncomplicated malaria. Antibodies causing rosette disruption were frequent only in adults with a long history of malarial exposure. Rosette disrupting antibodies do not appear to protect Papua New Guinean children or adults against cerebral malaria.

Adult↗

Evaluation of a new latex agglutination test for detecting human rotavirus in faeces.

Four methods for detecting rotaviruses (latex agglutination, electron microscopy, immunofluorescence and ELISA) have been compared on 57 faecal samples from children with acute diarrhoea. Complete agreement among the four techniques was found in 38 samples. One sample was positive by ELISA and latex agglutination but negative by the other two. For all the other samples there was agreement among three of the techniques only. In a blocking ELISA test, samples positive by ELISA only, turned out to be falsely positive. Assuming true positive or negative for those samples for which at least three techniques were in agreement, electron microscopy, ELISA and latex agglutination were more sensitive (96 per cent) than immunofluorescence (84 per cent). Electron microscopy was the most specific (96.4 per cent), followed by immunofluorescence (92.9 per cent), ELISA (89.4 per cent) and latex agglutination (85.9 per cent).

Diarrhea↗

Column agglutination technology: the antiglobulin test.

A new system for typing and screening blood, based on the sieving effect of glass bead microparticles, has been developed. The test is performed in a microcolumn in which the red cell agglutinates are trapped in the glass bead matrix during centrifugation, and unagglutinated cells form a pellet at the bottom of the column. Anti-human globulin reagents were incorporated in the diluent and the new test system, column agglutination technology, was compared to conventional tube tests and low-ionic-strength method. Sera and plasmas (228 samples) were screened for red cell antibodies with two anti-human globulin reagents: one containing only anti-IgG and the other containing both anti-IgG and anti-C3b, -C3d. After initial testing, there was 94-percent agreement between column agglutination technology and tube tests, and after repeat testing, there was 97-percent agreement. The column agglutination technology anti-human globulin test eliminates the need to wash red cells, which decreases the overall test time. The test is easy to perform, and the results are more objective than those with tube and microplate methods.

Antibodies, Anti-Idiotypic↗