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PubMed2006

Estrogen treatment success in recurrent and persistent labial agglutination.

STUDY OBJECTIVE: To estimate the success rate of conservative medical management and indications for surgery in cases of recurrent and/or persistent labial agglutination. DESIGN: A retrospective chart review was performed of girls treated for labial agglutination between 1996 and 2004. Records were reviewed for age, length of time of symptoms, previous treatments, results of topical estrogen therapy, and indications for surgery. SETTING: The study was performed in a tertiary care teaching university hospital. PARTICIPANTS: Charts of 67 girls with labial agglutination who were treated at the pediatric and adolescent gynecology clinic between 1996 and 2004 were reviewed. The average age was 4.1 years (range 0.6-14 years). INTERVENTIONS: None. MAIN OUTCOME MEASURES: Improvement of persistent or recurrent agglutination labial agglutination with estrogen. RESULTS: Out of the 67 charts reviewed, 48 had recurrent or persistent disease. Within those 48 girls, initial treatments included: topical estrogen in 40 (83%), oral and topical estrogen in 1 (2%), topical estrogen in addition to manual separation in 5 (10%), and treated with manual separation alone in 2 (4%). Five girls were immediately treated surgically due to urinary problems or parents declining further topical treatment. Forty-three were treated with topical estrogen therapy with the following results: 15 opened either partially or completely, 9 required surgery, and 19 did not follow up. In the subset of girls with prior manual separation, 2 had resolution of adhesions with estrogen, 3 required surgery, and 2 had no follow-up. CONCLUSION: This study suggests that re-treatment of persistent or recurrent labial agglutination with topical estrogen therapy following detailed application instruction leads to avoidance of surgical intervention in at least 35% of cases. Even in cases which previously required manual separation, an attempt at conservative medical management may be considered.

Administration, Topical↗
PubMed1979

Shear-induced concanavalin A agglutination of human erythrocytes.

The mechanism by which cell suspensions are agglutinated by plant lectins remains obscure. The agglutination of a particular cell line in the presence of a specific plant lectin probably depends on several factors including the number and valence of lectin molecules bound to the cell surface, the mobility of receptor molecules in the membrane, the surface morphology and charge and the metabolic state of the cell1-6. The assay system used to assess cell agglutination also seems to be important, since many laboratories studying the same agglutination reaction have reported dissimilar or contradictory results. To provide further information on the molecular mechanism of agglutination we have begun a systematic study on the aggregation of human red cells by the lectin concanavalin A (Con A). By using an adaptation of our previously described aggregation assay which provides a continuous measure of both the rate and degree of intercellular adhesion in the presence of controlled shear forces, we have found that the agglutination of erythrocytes by Con A can be resolved into three stages, two of which are observed only if the system is exposed to shear.

Cell Aggregation↗
PubMed1995

Evaluation of protein-A linked monoclonal antibody latex agglutination test for diagnosis of nuclear polyhedrosis virus (BmNPV) of silkworm Bombyx mori L.

The symptomology of BmNPV infection in Bombyx mori L depends on the stages of infection. Discernible symptoms develop at later stages of infection, which leads to improper diagnosis and poor crop yield with sericulturists. In the present study development of direct and protein-A linked monoclonal antibody latex (PALMAL) agglutination test for the detection of BmNPV infection in silkworm is described. Latex beads were precoated with protein-A and then sensitised with monoclonal antibody MA-231 (125 micrograms/ml). PALMAL test could detect 1 x 10(5) nuclear polyhedra/test and is ten times more sensitive than the direct agglutination test employing purified polyclonal antibodies. No agglutination was observed in presence of B. thuringiensis, S. marcescens, N. bombycis, group-A streptococci, Staphylococcus aureus, E. coli and normal haemolymph protein indicating the specificity of the test. Fifty haemolymph samples collected from the field were evaluated by PALMAL test. Twenty one samples having infection other than BmNPV, failed to show positive agglutination. Twenty five samples having > or = 5 x 10(6) BmNPV/ml showed positive agglutination. However, 4 samples having < 5 x 10(6) BmNPV/ml failed to show positive agglutination thereby indicating the limit of sensitivity of the assay.

Animals↗
PubMed1998

Construction of mono- and bivalent human single-chain Fv fragments against the D antigen in the Rh blood group: multimerization effect on cell agglutination and application to blood typing.

An expression system for mono- and bivalent single-chain Fv fragments (scFv) of a human antibody against D antigen in the Rh blood group system was established in Escherichia coli. The cDNA encoding the Fv fragment of the anti-D monoclonal antibody D10 was cloned using the polymerase chain reaction and expressed in E.coli by fusing with a peptide tag link in the C-terminus of the light chain variable region. The scFv fragment expressed by the bacteria produced specific agglutination of human D positive red cells in the presence of an anti-peptide tag antibody. Flow cytometric analysis clearly indicated that the bacterially prepared scFv showed high specificity and affinity for D antigen, which was identical with that of the parental IgG. In order to construct bivalent D10 scFv for use in direct cell agglutination, the scFv was fused with a dimeric protein, bacterial alkaline phosphatase (BAP). The fusion protein produced significant agglutination of human red blood cells with D antigen, confirming that the bacterially expressed fusion protein is a functional bivalent antibody fragment. Specific agglutination of D positive red cells by D10 scFv-BAP was enhanced in the presence of anti-BAP antibody, suggesting that further multimerization of scFv led to highly efficient cell agglutination. By grafting BAP enzymatic activity into the scFv fragment (enzyme-linked scFv), blood typing could conveniently be performed. These results indicate that bacterially expressed scFv and scFv-BAP would be of practical use in blood typing. The system reported here could also be applied to the examination of other cell surface antigens and cell agglutination.

Alkaline Phosphatase↗
PubMedDate not supplied

Rapid latex agglutination compared with the throat culture for the detection of group A streptococcal infection.

The Culturette Brand rapid latex agglutination test was compared with the throat culture for accuracy in detecting Group A beta-hemolytic streptococci (GABHS) on paired throat swabs from 1047 children with suspected streptococcal pharyngitis. In this comparison the rapid latex agglutination test had a sensitivity of 78%, a specificity of 88%, a positive predictive value of 52% and a negative predictive value of 96%. In 45 study patients from whom it was possible to obtain paired acute and convalescent sera, the latex agglutination test and the throat culture were compared against each other for detection of infection due to GABHS as evidenced by a 4-fold or greater titer rise of serum antistreptococcal antibodies. The latex agglutination test detected and failed to detect the same number of infections as the throat culture. Thus although a significant number of false positive latex agglutination tests occurred when compared to the throat culture, there is limited evidence in this study that the latex agglutination test is equal to the throat culture in detecting patients who have serologically confirmed infection due to GABHS.

Adolescent↗
PubMed1975

Effects of proteases and neuraminidase on RBC surface charge and agglutination. A kinetic study.

Electrophoretic mobility, membrane sialic acid content and agglutinability by "incomplete" antisera against Rh-o, hr' and k antigens were determined for red blood cells in the course of treatment with trypsin, ficin and neuraminidase. Neuraminidase gradually produces a slight to moderate agglutinability as it reduced surface charge density in proportion to the amount of sialic acid removed. Proteases acted in two distinct steps. The first stage is characterized by the cells rapidly becoming highly agglutinable and by the unmasking of new negative charge as the first half of the sialic acid is removed. In the second stage the cells show a slight gain in agglutinability as surface charge is removed in proportion to sialic acid removal as in the case of neuraminidase. Neuraminidase-treated cells are considerably less agglutinable than cells reduced to the same zeta-potential by protease treatment. The greater efficacy of proteases compared to neuraminidase in making cells agglutinable could be because they not only reduce surface charge density but also increase antigen-antibody bond strength, render antigens more mobile in the membrane to allow clustering in regions of cell to cell antibody bridging and remove glycopeptide chains which may be causing steric hindrance to antigen-antibody binding or to cell-cell contact.

Clostridium perfringens↗
PubMed1986

Comparisons of pooled polyclonal rabbit anti-human C3d with four monoclonal mouse anti-human C3ds. II. Quantitation of RBC-bound C3d, and characterization of antiglobulin agglutination reactions against RBC from 27 patients with autoimmune hemolytic anemia.

Labelled polyclonal IgG anti-C3d and monoclonal IgM and IgG anti-C3d antibodies (MAs) were employed at increasing antibody excess to measure the number of C3d molecules on human red blood cells (RBC) coated by complement in vitro and in vivo. Values for the number of C3d sites per cell determined with polyclonal anti-C3d were at least 4-fold higher than when MAs were used. The results suggest that the molar combining ratio for polyclonal anti-C3d with a single RBC-bound C3d fragment is more likely greater than 4.0 than 1.0 as previously assumed. Antiglobulin agglutination studies compared polyclonal and monoclonal anti-C3d antibodies against C3d-coated RBC from 27 patients with autoimmune hemolytic anemia. All four MAs showed striking prozones, requiring their use over a 25-fold higher range of dilutions than polyclonal anti-C3d. Polyclonal anti-C3d produced stronger agglutination reactions than any of the IgG MAs. Only the IgM MA produced agglutination as strong as, or stronger than, polyclonal anti-C3d. While IgM MA always gave the strongest MA agglutination reactions, no consistent ranking of the three IgG MAs was observed. Agglutination was not enhanced when all IgG MAs were combined; addition of IgG MAs to IGM MA reduced the strength of agglutination seen with IgM alone, suggesting blocking of IgM binding by competing IgG anti-C3d.

Anemia, Hemolytic, Autoimmune↗
PubMed1966

Agglutinating and precipitating capacity of rabbit anti-Salmonella typhosa gamma G and gamma M-antibodies during prolonged immunization.

Pike, Robert M. (University of Texas Southwestern Medical School, Dallas), Mary L. Schulze, and Cleo H. Chandler. Agglutinating and precipitating capacity of rabbit anti-Salmonella typhosa gammaG and gammaM antibodies during prolonged immunization. J. Bacteriol. 92:880-886. 1966.-Antibody produced in rabbits immunized with acetone-dried typhoid bacilli was followed over a period of 445 days by agglutination and by quantitative precipitation. Repeated injections of vaccine resulted in suppression of antibody titers. Both gammaG and gammaM antibodies were rapidly increased by booster injections after rest periods during which titers had decreased to low levels. The O agglutinin titers and the amount of antibody protein, as determined by precipitation with endotoxin, generally were parallel, except in serum specimens in which unusually large proportions of the agglutinating activity were found in the gammaG fraction. These exceptions were explained by the greater agglutinating capacity of the gammaM. Endotoxin precipitated about 10 times as much antibody from gammaG preparations as it did from gammaM fractions of equivalent agglutinating strength. A much higher proportion of the serological activity, therefore, was found in the gammaG fractions when antibody was measured by precipitation than when agglutination was used as the measure of activity.

Animals↗
PubMed1984

Latex agglutination test for detection of Clostridium difficile toxin in stool samples.

A total of 163 stool specimens were tested for detection of Clostridium difficile and its toxin by cytotoxicity assay with tissue culture, latex agglutination test, and isolation of the organism. From 33 specimens which were positive for toxin by cytotoxicity, 30 were positive by the latex agglutination test; the organism was isolated from 21. The total number of samples which were positive with the latex agglutination test was 44. The predictive value of a positive latex agglutination result relative to the cytotoxicity test was 68%, and the predictive value of a negative result was 97.5%. The specificity and sensitivity of the latex agglutination test relative to the cytotoxicity assay and the low cost and simple facilities required indicate that the latex agglutination test is a useful procedure for screening for C. difficile toxins, provided that positive latex results are confirmed by cytotoxicity assay.

Antitoxins↗
PubMed1984

Comparison of a latex agglutination test with other serological tests for the measurement of antibodies to Toxoplasma gondii.

One hundred sera from 49 patients with glandular toxoplasmosis were examined by a latex agglutination test, the dye test, an indirect haemagglutination test, and a double antibody sandwich enzyme linked immunosorbent assay (ELISA) for antitoxoplasma IgM. The results support previous findings that the dye test, indirect haemagglutination test, and latex agglutination test measure different antibodies to Toxoplasma gondii. In early glandular toxoplasmosis, when specific IgM was detected, the titres of both the latex agglutination test and the indirect haemagglutination test were lower than the dye test. Repeat specimens from 11 of the patients showed four cases in which the latex agglutination test titres never exceeded 1/256, whereas both the dye test and the indirect haemagglutination test showed significant titres and specific IgM was detected in every case. We conclude that the latex agglutination test should not be used as a substitute for the dye test in the serological diagnosis of glandular toxoplasmosis. All sera giving a positive latex agglutination test result should be referred for further tests. A combination of the dye test and double antibody sandwich ELISA gives the most reliable serological diagnosis of early glandular toxoplasmosis.

Antibodies↗
PubMed1993

Characterization of cell surface properties in agglutinable and nonagglutinable mutants of Pseudomonas putida.

Cells of an aggressive, root-colonizing isolate of Pseudomonas putida are agglutinated by a root surface glycoprotein. The agglutination phenotype in P. putida isolate Corvallis is lacking in mutants (Agg-) derived by Tn5 insertion and chemical mutagenesis. Specific mutation in the aggA locus by Tn5 insertion results in loss of agglutinability that is complemented in trans by a wild-type copy of the P. putida aggA locus. We examined the biochemical bases of agglutination in P. putida by comparing cell surface features in Agg+, Agg- mutants, and a genetically restored aggA mutant. No changes in gross cell surface features involving hydrophobic or hydrophilic binding or net negative charge were observed. Three macromolecular features, pili, flagella, and lipopolysaccharide size, did not differ between Agg+ and Agg- mutants. Protein profiles of cell envelope, periplasmic, and outer membrane preparations revealed pleiotropic effects of mutation in agglutination phenotype including alterations of an outer membrane protein of 47,000 molecular weight and periplasmic proteins of 56,000 and 60,000 molecular weight. The protein alterations seen in the aggA::Tn5 Agg- mutant 5123 reverted to wild-type patterns upon introduction of a wild-type copy of the aggA locus. These data suggest agglutinability may be conditioned by more than one proteinaceous component associated with the bacterial envelope layers.

Bacterial Outer Membrane Proteins↗
PubMed2001

Echicetin, a GPIb-binding snake C-type lectin from Echis carinatus, also contains a binding site for IgMkappa responsible for platelet agglutination in plasma and inducing signal transduction.

Echicetin, a heterodimeric snake C-type lectin from Echis carinatus, is known to bind specifically to platelet glycoprotein (GP)Ib. We now show that, in addition, it agglutinates platelets in plasma and induces platelet signal transduction. The agglutination is caused by binding to a specific protein in plasma. The protein was isolated from plasma and shown to cause platelet agglutination when added to washed platelets in the presence of echicetin. It was identified as immunoglobulin Mkappa (IgMkappa) by peptide sequencing and dot blotting with specific heavy and light chain anti-immunoglobulin reagents. Platelet agglutination by clustering echicetin with IgMkappa induced P-selectin expression and activation of GPIIb/IIIa as well as tyrosine phosphorylation of several signal transduction molecules, including p53/56(LYN), p64, p72(SYK), p70 to p90, and p120. However, neither ethylenediaminetetraacetic acid nor specific inhibition of GPIIb/IIIa affected platelet agglutination or activation by echicetin. Platelet agglutination and induction of signal transduction could also be produced by cross-linking biotinylated echicetin with avidin. These data indicate that clustering of GPIb alone is sufficient to activate platelets. In vivo, echicetin probably activates platelets rather than inhibits platelet activation, as previously proposed, accounting for the observed induction of thrombocytopenia.

Acetates↗
PubMed2001

Bilinexin, a snake C-type lectin from Agkistrodon bilineatus venom agglutinates platelets via GPIb and alpha2beta1.

A new snake protein, named bilinexin, has been purified from Agkistrodon bilineatus venom by ion-exchange chromatography and gel filtration chromatography. Under non-reducing conditions it has a mass of 110 kDa protein on SDS-PAGE. On reduction, it can be separated into five subunits with masses in the range 13-25 kDa. The N-terminal sequences of these subunits are very similar to those of convulxin or the alboaggregins, identifying bilinexin as a new member of the snake C-type lectin family, unusual in having multiple subunits. Bilinexin agglutinates fixed platelets. washed platelets and platelet rich plasma (PRP) without obvious activation (shape change) as confirmed by light microscope examination. Both inhibitory and binding studies indicate that antibodies against alpha2beta1 inhibit not only platelet agglutination induced by bilinexin, but also bilinexin binding to platelets. VM16d, a monoclonal anti-GPIbalpha antibody, completely inhibits platelet agglutination induced by bilinexin, and polyclonal antibodies against GPIbalpha prevent its binding to platelets. However, neither convulxin, polyclonal anti-GPVI antibodies, nor GPIIb/IIIa inhibitors affect its binding to and agglutination of platelets. Bilinexin neither activates GPIIb/IIIa integrin on platelets nor induces tyrosine phosphorylation of platelet proteins, nor increases intracellular Ca2+ in platelets. Like alboaggregin B, bilinexin agglutinates platelets, which makes it a good tool to investigate the differences in mechanism between snake C-type lectins causing platelet agglutination and those that induce full activation.

Amino Acid Sequence↗
PubMed1998

Comparison of tube and gel red blood cell agglutination techniques in detecting chimeras after major ABO-mismatched allogeneic hematopoietic stem cell transplantation.

We compared the ability of tube and gel red blood cell (RBC) agglutination techniques to follow erythroid engraftment in a patient who received a major ABO-mismatched peripheral blood stem cell transplant and bone marrow transplant. Tube and gel RBC agglutination techniques were used to detect mixed-field reactivity in cell mixtures containing A/O and c+/c- RBCs and the ability of these two technologies to detect RBC chimeras were compared. We detected c+ RBCs in c+/c- RBC populations microscopically at 1% by the tube RBC agglutination technique, but not until 10% by the gel technique. Group A RBCs in A/O RBC populations were detected at 10% by both techniques. In the patient studied, group A RBCs and c+ RBCs were detected on Days 20 and 14, respectively, with the tube RBC agglutination technique, but neither marker was detected until Day 26 with the gel technique. Tube and gel RBC agglutination techniques comparably identified ABO mixed fields. Although the tube RBC agglutination technique showed greater sensitivity than the gel technique in detecting the c antigen, the gel technique was easier to use and allowed more reliable interpretation of mixed fields by the technologist.

Journal Article↗
PubMed1990

The role of the membrane skeleton in concanavalin A-mediated agglutination of human erythrocytes.

In the erythrocyte membrane, the mobility of band 3 protein, the receptor for concanavalin A (Con A), is drastically reduced by the membrane skeleton. Yet, the vesicles free of membrane skeletal proteins, isolated from the highly agglutinable proteinase-treated cells, are found to be devoid of Con A agglutinability. The vesicles bind Con A in normal amounts, and remain agglutinable with the wheat germ and Ricinus agglutinins. Intracellular entrapment of monospecific antibodies to spectrin and 4.1 protein (two of the major skeletal components of the membrane) is also found to inhibit agglutination by 30-50%. Thus the membrane skeleton appears to play a positive role in the agglutination of the cells with Con A. The anti-ankyrin antibodies are found to be without any effect. The anti-band 3 (cytoplasmic domain) antibodies are also inhibitory to agglutination. Since Con A binding to cells alters the shape responses and deformability of the cells, and the cells resist fragmentation at 49 degrees C, the properties of the whole skeleton, especially spectrin, appear to be changed. The Con A-bound membranes also do not release the complex of spectrin-band 4.1-actin when extracted with a hypotonic medium. It appears that Con A binding leads to interaction of the cytoplasmic domain of the receptor with a skeletal component, possibly spectrin. Subsequent to this, the receptor molecules and the skeletal proteins undergo aggregation in the membrane, which is detected by their crosslinking by an 8.6-A span bifunctional reagent. The contractility believed to be associated with the membrane skeleton may be responsible for the aggregation.

Anion Exchange Protein 1, Erythrocyte↗
PubMed1989

Role of botrocetin in platelet agglutination: formation of an activated complex of botrocetin and von Willebrand factor.

Botrocetin (venom coagglutinin) induces binding of von Willebrand factor (vWF) to platelet glycoprotein Ib (GPIb), resulting in platelet agglutination. A mechanism whereby botrocetin causes vWF to change to an active platelet-agglutinating form is proposed. Incubation of native vWF with botrocetin yielded an increasingly active vWF with slower migration in two-dimensional immunoelectrophoresis but with no apparent change in vWF multimer pattern. The "activated" vWF eluted mainly in the void volume (Vo) (Bio-Gel A-15m column chromatography). Botrocetin eluted in the included volume (Vi). Vo peaks appeared to contain a vWF-botrocetin complex, based on bioassays and immunoassays. 125I-Botrocetin mixed with vWF eluted in two peaks: in the Vo, coincident with active vWF, and in the Vi. With von Willebrand disease (vWD) plasma lacking vWF, 125I-Botrocetin eluted in the Vi only. It did not bind to platelets without vWF. In aggregometric studies, antibodies (Ab) against botrocetin, vWF, and GPIb prevented botrocetin-induced platelet agglutination and caused dissolution of preformed platelet agglutinates. Immunostaining of aggregates with antibotrocetin Ab revealed a positive reaction. Botrocetin appears to act in a two-step manner, first binding with vWF to form a complex, which then binds to GPIb to cause agglutination. All three components, vWF, botrocetin, and GPIb, appear to be required for maintenance of stable platelet agglutinates.

Animals↗
PubMed1989

Effect of cisplatin on con A agglutinability of different lymphoid cells of Swiss albino rats.

Thymocytes, splenocytes, and lymph node cells showed a differential degree of agglutination which con A, which was the lowest for thymocytes and the highest for lymph node cells. Cisplatin treatment of the cells showed a gradual increase and then decrease in the degree of agglutination of the cells which varied with cisplatin concentration and time of treatment. The cells treated with 20 micrograms/ml of cisplatin for 30 min showed the maximum increase in the degree of con A agglutination. Incubation of these cisplatin-treated cells with D-xylose, D-glucose, or sialic acid before con A agglutination showed a decrease in the cell agglutinability which was the lowest for sialic acid-incubated cells. It is suggested that the removal of cell surface carbohydrate moieties after cisplatin treatment may play a role in the changes in con A agglutination of these cells.

Animals↗
PubMed1984

Agglutination of formalin-fixed, platelet-type von Willebrand's disease platelets by human von Willebrand factor.

The interaction of platelets and von Willebrand factor (vWF) in platelet-type von Willebrand's disease (vWD) was characterized using formalin-fixed platelets from the patients. Formalin-fixed patient platelets were agglutinated directly by human vWF in normal plasma and type IIB vWD plasma, but not in type IIA vWD plasma. In the presence of a small amount of normal vWF, ristocetin-induced agglutination of patient platelets was enhanced with low concentrations of ristocetin. Wheat germ agglutinin and EDTA inhibited vWF-induced agglutination, although EDTA had no effect on ristocetin (plus vWF)-induced agglutination. These results demonstrate that vWF-induced agglutination of platelet-type vWD platelets is independent of active platelet metabolism but requires divalent cations, and suggest that platelet membrane glycoprotein I (GPI) would be involved in this agglutination.

Blood Coagulation Factors↗