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PubMed2002

Quantitation of hyaluronic acid in serum with automated microparticle photometric agglutination assay.

A microparticle photometric agglutination assay to quantitate hyaluronic acid (HA) in serum has been developed. The principle of the method is that hyaluronic acid binding protein covalently sensitized on microparticle surface initiates the particles to agglutinate in the presence of HA. By measuring the time-course of transmittance changes at 800 nm, due to the particles' agglutination, HA concentration is estimated as a function of the magnitude of agglutination in a fully automated immunochemistry analyzer. The analytical range for HA was found to be between 10 and 1200 ng/mL. The precision (CV) was between 3.0 and 8.4% in the intra-assay (n = 10), and 4.8 and 8.9% in the inter-assay (n = 3). The lower limit of detection was 10 ng/mL. The deviation of the linearity study indicated within 8% of expected values, and the analytical recovery was between 96.5 and 106.3%. The correlation coefficient against HA plate ELISA was 0.989 with a slope of 1.01 (n = 31).

Agglutination Tests↗
PubMed1958

Characterization of the reactant (gamma globulin factor) in the F II precipitin reaction and the F II tanned sheep cell agglutination test.

The material in gamma globulin ("reactant") which reacts with rheumatoid sera in the F II precipitin and F II tanned sheep cell agglutination tests was concentrated by precipitation with sodium sulfate. The concentrated "reactant" appeared to consist of polydispersed molecular aggregates of gamma globulin with s(20) constants as high as 40, as well as the previously described inhomogeneous aggregated material. Aggregated gamma globulin precipitated readily with most rheumatoid sera regardless of the reaction volume, and in low concentration inhibited the F II tanned sheep cell agglutination reaction and sensitized tanned erythrocytes to the agglutinating action of a positive rheumatoid serum. On the other hand, non-aggregated gamma globulin (7S) did not precipitate with rheumatoid sera and in low concentration did not inhibit the F II tanned sheep cell agglutination reaction, or sensitize tanned erythrocytes. Non-aggregated gamma globulin in large excess inhibited the precipitin reaction of aggregated gamma globulin with "rheumatoid factor," and accounted for the characteristic shape of the whole F II precipitin curves and the volume effect described by Vaughan (relation of increased precipitate yield relative to the reaction volume in whole F II precipitin studies). In serological systems other than the F II tanned sheep cell and F II precipitin reactions, the sensitization involves an antigen-antibody combination; i.e., sheep erythrocyte plus hemolysin in the sensitized sheep cell test, and egg albumin plus anti egg albumin in the absorption experiments with specific precipitates. The aggregation of gamma globulin that was essential for sensitization in the F II tanned sheep cell and F II precipitin tests may have simulated the aggregation of antibody gamma globulin that occurs with antigen-antibody union. The present information has been incorporated into a schematic hypothesis for the basis of the rheumatoid serological reactions.

Agglutination Tests↗
PubMed1977

Immunodiffusion and agglutination tests for Candida in patients with neoplastic disease: inconsistent correlation of results with invasive infections.

A serological study of candidiasis was conducted with use of (1) sera sent to the laboratory by clinicians who suspected infections due to various organisms including Candida species, and (2) sera available in our serum bank from patients with candidiasis proven at autopsy and from those with documented candidemia. With this population of patients, we were able to evaluate both potential false-negative and false-positive results. Microimmunodiffusion and slide agglutination tests were used. In many cases, serial specimens were available for measurement of rises or falls in titers of agglutinating antibody. Sera from less than one-half of the patients with disseminated or invasive gastrointestinal candidiasis exhibited positive immunodiffusion reactions, titers of agglutinating antibody of greater than 1:16, or fourfold rises in titer of agglutinins. Sera from several patients with pharyngitis due to Candida and from several who were only colonized with Candida or for whom clinical or cultural evidence of candidiasis was lacking showed positive immunodiffusion reactions or agglutinin titers of greater than 1:16, and some showed fourfold rises in titer. Conversions from negative to positive immunodiffusion reactions were not consistently correlated with invasive candida infection. Using the methods described, we have not found immunodiffusion tests and titers of agglutinating antibody to be reliable indicators of invasive candida infection, since false-positive as well as false-negative reactions occur. Greater specificity for invasiveness as well as greater sensitivity in immunosuppressed patients are necessary before these tests can become important adjuncts to the evaluation of patients with suspected invasive candidiasis.

Adolescent↗
PubMed1976

Concanavalin A agglutinability of a temperature-sensitive mutant of Rous sarcoma virus.

Concanavalin A (Con A) concentration dependence of agglutinability of a mutant of Rous sarcoma virus which is temperature-sensitive for transformation was examined. Con A agglutinability of the virion was quantitatively expressed by measuring radioactivities of 60 to 70 S RNA extracted from Con A-agglutinated material. The mutant grown at a permissive temperature (35 degrees C) agglutinated at a significantly lower concentration of Con A, compared with that at a non-permissive temperature (40 degrees C).

Agglutination↗
PubMed1978

Mechanism of glucan-induced agglutination in Streptococcus mutans. I. Binding of radioactive glucan to whole cells of S. mutans OMZ-176.

The binding of radioactive glucan to Streptococcus mutans cells, which are agglutinated by dextrans, was examined. The glucan was synthesized from sucrose by extracellular glucosyltransferases from S. mutans FA-1 and was highly branched at C-3 and C-6 of D-glucose residues, containing 17% of a (1 leads to 3)inter-chain residues. Binding of glucan to whole cells of S. mutans OMZ-176, which were agglutinated by addition of glucan or Dextran T2000, was irreversible and followed saturation type kinetics; saturation was achieved at approximately 110 ng of glucan per ml. About 14 ng of glucan were bound per mg of the cells at the saturated concentration. The heated cells of this organism, however, had a relatively low ability of glucan-binding, compared with the freshly prepared and lyophilized cells. Binding to the heated cells was entirely of a non-saturation type. Binding of Dextran T2000 or T10 was determined by competition between the labeled glucan and unlabeled Dextrans for the binding site(s). Both Dextrans and glucan from S. mutans FA-1 were bound to the same site(s). Other organisms, which did not undergo glucan- and Dextran-induced agglutination, had a relatively lower ability of glucan-binding than S. mutans, which was agglutinated.

Agglutination↗
PubMed1980

Concanavalin A agglutinability of some enveloped RNA viruses modified by host cell transformation.

The dependence on concanavalin A (Con A) concentration of agglutinability of some enveloped RNA viruses grown in transformed cells was compared with that of those grown in nontransformed cells. The avian oncoviruses were purified by centrifuging to equilibrium in a combination equilibrium: viscosity gradient of potassium tartrate and glycerol after conventional isopycnic sucrose density gradient centrifugation. Avian oncoviruses were more agglutinable with Con A when grown in transformed cells than when grown in nontransformed cells. Vesicular stomatitis virus grown in transformed cells was also more agglutinable than the virus grown in nontransformed cells. These results agree with the concept that the envelopes are modified by host cell transformation and that, therefore, viruses grown in transformed cells are expected to be more agglutinable with Con A than those grown in nontransformed cell.

Agglutination↗
PubMedDate not supplied

Separation of normozoospermic human spermatozoa into subpopulations by selective agglutination with peanut agglutinin.

Incubation of human spermatozoa of normozoospermic origin with the galactose specific lectin peanut agglutinin (PNA) resulted in agglutination of the majority of sperm. This finding enabled separation of sperm into two subpopulations. The major one, accounting for 87.0 +/- 12.7 (SD)% consisted of agglutinating sperm (PNA+), while the minor subpopulation (PNA-) did not bind the lectin. The correlation between the percentages of PNA- sperm and acrosome-damaged sperm, as detected by light microscopy prior to separation, was analysed and an overlapping has been found. Light and electron microscopy examination revealed that the PNA- cells were either acrosomeless or possessed severely damaged acrosomes while the PNA+ sperm were mostly free of such pathologies. Following treatment of sperm with fluorescin-conjugated PNA the single cells lacked any labeling while the agglutinates exhibited fluorescence. However, the binding of the lectin to sperm was non-uniform and differences in fluorescence intensity at various parts of the head have been observed. The sialic acid content in PNA+ sperm was found to be significantly higher (7.5 +/- 2.2 micrograms/10(8) sperm) as compared to PNA- sperm (2.1 +/- 0.6 micrograms/10(8) sperm). It was suggested that sialic acid content could be a biochemical indicator of acrosomal integrity. Separation of sperm by selective PNA agglutination might be valuable for elimination of sperm affected by acrosomal pathologies from the ejaculate.

Galactose↗
PubMed2006

Contraceptive effect of sperm-agglutinating factor isolated from Staphylococcus aureus in mouse.

OBJECTIVE: To investigate the contraceptive effect of sperm-agglutinating factor (SAF) isolated from Staphylococcus aureus in mouse. DESIGN: Experimental study performed with LACA mice obtained from the Central Animal House, Panjab University, Chandigarh, India. SETTING: In vivo studies conducted in the Department of Microbiology, Panjab University, Chandigarh, India. POPULATION: Sixty female and 18 male mice were used for the studies. METHODS: Mice sperm-S. aureus agglutination, scanning electron microscopy (SEM), in vivo studies in mice. MAIN OUTCOME MEASURE: Contraceptive efficacy of SAF. RESULTS: S. aureus readily adhered to and agglutinated mouse spermatozoa. By SEM, S. aureus adherence was observed on sperm head as well as sperm tail. SAF was found to be causing 100% fertility inhibition in mouse with no effect on vaginal epithelium. CONCLUSIONS: Sperm-agglutinating factor has been found to have a potential as a contraceptive agent.

Agglutinins↗
PubMed1995

Agglutination of Staphylococcus saprophyticus: a structural and cytochemical study.

Staphylococcus saprophyticus was shown to be agglutinated by wheat germ agglutinin, wheat germ agglutinin-biotin and bovine serum albumin-p-aminophenyl-N-acetyl-beta-D-glucosaminide (GlcNAc-BSA), and sheep red blood cells. In these agglutinations, filamentous or amorphous structures radiating from the surface of S. saprophyticus were demonstrated by electron microscope observation. Cytochemical analyses of the agglutination revealed the binding sites of wheat germ agglutinin in S. saprophyticus and the binding sites of GlcNAc in the sheep red blood cells and S. saprophyticus. Since GlcNAc-BSA contains N-acetylglucosamine to which wheat germ agglutinin can bind, it is most likely that an interaction between a wheat germ agglutinin-bindable substance in S. saprophyticus and an N-acetylglucosamine-bindable substance in sheep red blood cells is involved in the agglutination.

Acetylglucosamine↗
PubMed1998

Vi-deficient and nonfimbriated mutants of Salmonella typhi agglutinate human blood type antigens and are hyperinvasive.

We generated nonfimbriated mutants from both Vi-positive and -negative Salmonella typhi to analyze the role of type 1 fimbriae and Vi-antigen in bacterial invasion. A Vi-defective mutant of S. typhi GIFU 10007-3 was more invasive than the wild-type strain GIFU 10007. The wild-type strain expressing Vi-antigen did not agglutinate both Saccharomyces cerevisiae and human erythrocytes but Vi-defective mutants were able to agglutinate S. cerevisiae and human erythrocytes. Nonfimbriated mutants from Vi-negative GIFU 10007-3 lost the ability to adhere to S. cerevisiae but still could agglutinate human erythrocytes. The Vi-negative mutant increased secreted proteins and became 5-fold more invasive than the wild-type strain. Nonfimbriated Vi mutants became 50-120-fold more invasive than the wild-type GIFU 10007. To determine why nonfimbriated Vi mutants still agglutinate human red blood cells, we searched bacterial proteins that could bind human blood-type antigens. We finally identified a candidate 37 kDa outer membrane protein that recognized fucosyl-galactose, a structure common to blood type A, B and H antigens.

ABO Blood-Group System↗
PubMed1987

The specificity of antisera against Bordetella pertussis examined by bacterial agglutination.

The specificity of conventional, adsorbed antisera against agglutinogens 1, 2, and 3 of Bordetella pertussis was examined by slide agglutination and by agglutination in microtitre wells. Unadsorbed hyperimmune sera showed higher agglutinating activity against autologous or homologous cells than against cells of heterologous serotype. Adsorption of sera with heterologous cells increased the serotype specificity considerably. In spite of extensive adsorption, these anti-agglutinogen sera were still found to cross-react with B. parapertussis and/or B. bronchiseptica strains. Adsorption experiments with B. pertussis hyperimmune sera against serotype 1-, 1.2-, and 1.3-organisms demonstrated that the cross-reacting surface antigens differed from the agglutinogens 1, 2, and 3. Thus, in making species-specific reagents for diagnostic use it may be of value to include adsorption with B. parapertussis and probably with B. bronchiseptica. Limited data indicated that there is no need to use B. avium for adsorption. The agglutination assays were also used to test three monoclonal antibodies stated to be specific for the agglutinogens 1, 2, and 3, respectively. Some anomalous behaviour for the anti-agglutinogen 1 reagent was found, whereas the anti-agglutinogen 2 and 3 reagents corresponded well with the present polyclonal factor sera.

Agglutination Tests↗
PubMed1978

Role of cell-cell interactions in mitogenic stimulation of lymphocytes. I. Dissociation on concanavalin A-inducible lymphocyte activation and agglutination.

The aim of the study was to decide whether the delayed agglutination of lymphocytes following mitogenic doses of concanavalin A (Con A) is a prerequisite of the activation process. It was shown that both phenomena can be greatly dissociated; suitable doses of cytochalasin B (CB) completely block agglutination, while the capacity to respond (by [14C]thymidine incorporation) to Con A-induced stimulation is retained. It was concluded that agglutinability is acquired in the early phase of the activation process, concomitant with induced changes in the cell membrane structure; the manifestation (i.e. agglutination) of this capacity is not necessary for the activation of the cell nucleus to take place, and it depends on the cells' chances of being brought together, either by active movement or by external forces.

Agglutination↗
PubMed1965

APPLICATION OF A MICROTECHNIQUE TO THE AGGLUTINATION TEST FOR LEPTOSPIRAL ANTIBODIES.

A microtechnique has been developed and adapted successfully to the microscopic agglutination test with live antigens for detection of leptospiral antibodies. Simultaneous titrations were performed by the conventional microscopic agglutination test and the microtechnique. When the microtechnique was used to screen 50 unknown leptospiral strains with a battery of hyperimmune sera, 98% agreement was obtained with the conventional procedure. Comparative data on 635 tests on these 50 cultures established the reliability of the microtechnique. Results with the two tests on 46 human sera revealed 93% agreement in the detection of leptospiral antibodies. The validity and reliability of the microtechnique obtained in these comparative studies suggests that it can be used as a valuable screening procedure for the microscopic agglutination test for preliminary cross agglutination studies on unknown strains and for the detection of leptospiral antibodies in human and animal sera.

Agglutination Tests↗
PubMed1966

Modified agglutination test for Pasteurella tularensis.

Several modifications in technique were incorporated into the standard agglutination test for Pasteurella tularensis. Reciprocal shaking of all tubes in a Kahn shaker was introduced to increase the rate of agglutination and quantity of agglutinated cell mass, making it possible to report preliminary results within 4 hr. Increased incubation time at a higher temperature was used to favor the rate of agglutination. A serum control for each serum tested was necessary to detect false positive tests. Finally, a verification procedure with 5% NaCl used as the diluent was instituted to prevent these false positive reactions.

Agglutination Tests↗
PubMed1977

Demonstration of enterobacterial common antigen by bacterial agglutination.

Potent antisera against the enterobacterial common antigen (ECA) agglutinate R bacteria of the Enterobacteriaceae family that possess unimpaired R-core structures of the Escherichia coli R1 or E. coli R4 core type. In these strains, known to be ECA immunogenic, ECA is most probably linked to the lipopolysaccharide R core. R mutants of other core types (e.g., Salmonella Ra, E. coli R2 or R3) or R mutants with incomplete core structures of the E. coli R1 type, as well as an rfaL mutant deficient in the O-translocase system, agglutinate to a much lesser extent or not at all. All the later mutants are nonimmunogenic; they possess the ECA in a free form, not linked to the R core. None of the S forms tested from many different enterobacterial genera was found to be agglutinable with the ECA antiserum. The dynamics of the ECA agglutinin formation in rabbits parallels the ECA hemagglutinin formation, indicating that the same antibody class might be involved in bacterial agglutination and hemagglutination.

Agglutination↗
PubMed1972

Agglutination of Staphylococcus aureus by rabbit sera.

Of 137 Staphylococcus aureus strains, 87 agglutinated in normal rabbit serum. The agglutination was shown to be caused by the Fc-part of immunoglobulin G (IgG). F(ab(1))(2)-fragments of IgG and immunoglobulin M (IgM) in corresponding concentrations were unreactive. The agglutinating strains had a high or moderate content of protein A. Strains with a low content of protein A and protein A-negative mutants did not agglutinate. The importance of the reaction between the Fc part of IgG and protein A for serotyping of S. aureus is demonstrated. Two alternative methods for serotyping S. aureus are suggested, using either F(ab(1))(2) fragments of IgG or intact IgM.

Agglutination Tests↗
PubMed1992

Avian P1 antigens inhibit agglutination mediated by P fimbriae of uropathogenic Escherichia coli.

Whole egg white from pigeon, dove, and cockatiel eggs, as well as the ovomucoid fraction of pigeon egg white, exhibited strong P1 antigenic activities and inhibited agglutination of human P1 erythrocytes and of digalactoside-coated latex beads by P-fimbriated Escherichia coli strains. In contrast, chicken egg white exhibited only weak P1 antigenic activity and had little impact on P-fimbrial agglutination. These preparations did not affect hemagglutination by E. coli strains expressing mannose-resistant adhesins other than P fimbriae, i.e., Dr, F1845, and S adhesins. Human anti-P1 serum diminished the P-fimbrial inhibitory activities of pigeon egg white and pigeon ovomucoid. Pigeon ovomucoid was equipotent on a molar basis with globoside, and the pigeon, dove, and cockatiel egg white preparations were equipotent with each other in P-fimbrial inhibition. Incubation of p erythrocytes in whole egg whites or in pigeon ovomucoid did not render them agglutinable by P-fimbriated bacteria, whereas incubation in globoside did. These data demonstrate that whole egg whites (and their ovomucoid fraction) from members of the families Columbidae (pigeons and doves) and Psittacidae (parrots) specifically and potently inhibit P-fimbrial agglutination, probably by providing P1 antigen as a receptor for the P-fimbrial adhesin. Avian egg white preparations may facilitate adhesin characterization of wild-type uropathogenic strains and may useful in preventing upper urinary tract infections due to P-fimbriated E. coli.

Adhesins, Escherichia coli↗
PubMed1982

Improved rapid slide agglutination test for presumptive diagnosis of canine brucellosis.

A modified rapid slide agglutination test for the presumptive identification of Brucella canis infection in dogs has been developed. The method required mixing 0.1 ml of canine serum with 0.1 ml of 0.2 M 2-mercaptoethanol solution. Equal volumes (0.05 ml) of the treated serum and the B. canis plate antigen were mixed. Agglutination results were read within 2 min. Clinical studies showed 100% agreement between this method and the conventional 2-mercaptoethanol tube agglutination test. Excellent correlation was shown between cultural isolation and the modified rapid slide agglutination test, using sera from experimentally infected dogs.

Agglutination Tests↗