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PubMed2001

[Surface properties of Lactobacillus strains. I. Hemagglutination and hydrophobicity].

Bacteria possess many surface membrane properties, both mechanical and biochemical, that allow them to interact with their environment These properties may affect a host in either positive (beneficial) or negative (pathological) ways. All surface properties of bacteria are yet unknown therefore we attempt to increase our knowledge regarding specific strains of lactobacilli, by examining the known properties including hemagglutination and hydrophobicity. The purpose of this study was to evaluate the cell surface properties of certain strains of Lactobacillus. These strains isolated from the human vagina and gastrointestinal tract were selected because of their antagonism toward aerobic and anaerobic bacterial pathogens. Part I discusses the hydrophobicity and hemagglutination abilities of these Lactobacillus strains.

Digestive System↗
PubMed1990

Chemically sensitized erythrocytes for hemagglutination reactions.

The use of chemically modified indicator erythrocytes for hemagglutination reactions can result in increased sensitivity. Treatment of erythrocytes with polyvinylpyrrolidone (PVP) or dextran T40 (10% weight/volume) induces changes in the cell surface in the form of extensions and blebbing, thereby increasing the surface area. These sensitized cells can be used in forensic science when detection or quantitation of erythrocyte surface reacting antibodies is important. The effect of altering membrane lipid fluidity on erythrocyte surface antigens has also been investigated. Treatment of cells with a reagent that increases the membrane ratio of cholesterol to phospholipid results in enhanced hemagglutination capacity despite the lack of extensive spiculation.

ABO Blood-Group System↗
PubMedDate not supplied

Pathogenicity and serovar-specific hemagglutinating antigens of Haemophilus paragallinarum serovar B strains.

The pathogenicity and presence of serovar-specific hemagglutinating (HA) antigens of Haemophilus paragallinarum serovar B reference strains 0222 and Spross and field isolates 24268 and 24317 were investigated. Chickens challenged with all strains except strain 0222 showed clinical signs of infectious coryza. For all four strains, challenged chickens had intrasinus lesions and were colonized by the challenge organism. Before and after hyaluronidase treatment, strains 0222, 24268, and 24317 showed HA activity against formaldehyde-fixed chicken erythrocytes but not against fresh chicken erythrocytes. Strain Spross expressed HA activity only after treatment. In cross-hemagglutination-inhibition tests, the four serovar B strains cross-reacted with each other but not with serovar A and C strains. Cross-adsorption tests indicated that strain 24317 has a wider range of HA antigens than the other two strains. Our results indicated that H. paragallinarum serovar B strains are pathogenic for chickens and that they possess six different HA antigens, one of which is specific for serovar B strains.

Animals↗
PubMedDate not supplied

Characterization of two new monoclonal antibodies against Haemophilus paragallinarum serovar C hemagglutinating antigen.

Two new monoclonal antibodies (MAbs), D6D8D5 and B3E6F9, both directed against Haemophilus paragallinarum serovar C hemagglutinating (HA) antigen, were produced, and characteristics of the MAbs were compared with those of the previously described MAb F2E6 in dot-blot and hemagglutination-inhibition (HI) tests using two representative H. paragallinarum strains each of serovars A, B, and C strains and 55 Japanese serovar C field isolates. MAb D6D8D5 and MAb F2E6 reacted with all serovar C strains and field isolates in the dot-blot test. However, MAb D6D8D5 showed various degrees of inhibition of the HA activity of field isolates. In the enzyme-linked immunosorbent assay-competition test, MAb D6D8D5 did not compete with MAb F2E6. MAb B3E6F9 reacted with strain S1, serovar C but not with strain Modesto, serovar C in both dot-blot and HI tests. Three out of 55 field isolates did not react with MAb B3E6F9. Neither MAb reacted with the serovar A and B strains.

Animals↗
PubMedDate not supplied

Hemagglutinating activity and immunological properties of Haemophilus paragallinarum field isolates in Japan.

Four field isolates (S4, S10, S15, and S17) of Haemophilus paragallinarum were recovered from chickens affected with infectious coryza in widely separated regions of Japan. Their hemagglutinating (HA) activity and immunological properties were compared with those of strain 221 of serovar A/1 and strains Modesto and S1 of serovar C/2. When treated with potassium thiocyanate or hyaluronidase, all the isolates showed HA activity against formaldehyde-fixed chicken erythrocytes but not against fresh chicken erythrocytes. In the hemagglutination-inhibition (HI) test, the isolates cross-reacted with strains Modesto and S1 but not with strain 221. The immunological properties of these isolates, as determined by cross-protection tests, were similar to those of strain S1 and, to a lesser degree, strain Modesto, but not to strain 221. Our results indicated that the four field isolates belong to serovar C/2 and that the HI test is a suitable method for serotyping H. paragallinarum.

Animals↗
PubMed1979

[Hemagglutinating activity and morphology of antigen K 99 in enterotoxic strains of E. coli isolated from calves].

The hemagglutination activity and morphology of antigen K 99 in enterotoxic E. coli strains isolated from calves was studied. It was proven that antigen K 99 is produced not at 18 degrees C, but at 37 degrees C. All K 99+ E. coli strains react with absorbed anti K 99 serum, showing various anti-agglutination titers. The hemagglutination activity of K 99+ E. coli strains is inhibited by absorbed K 99 antiserum. In immunodiffuse tests all K 99+ E. coli strains react by producing a single precipitation line. It is proven electronmicroscopically that on the surface of the bacterial cell of K 99+ E. coli strains is observed a filamentous structure, consisting of numerous fine fibers which give it a fibriform outlook. No such morphological structures are observed in K 99- E. coli strains.

Absorption↗
PubMed1970

Complement-fixation and hemagglutination antigens from a Chlamydial (ornithosis) agent grown in cell cultures.

Methods are described for the preparation of complement-fixation (CF) and hemagglutination (HA) antigens from the Texas turkey ornithosis agent grown in McCoy cell culture monolayers. The particulate antigens prepared for this study were satisfactory for testing mammalian sera by direct CF tests and avian sera by indirect CF or modified direct CF tests. Comparison of titers were made on human, bovine and ovine sera using direct CF tests employing antigen prepared for this study, 6 BC yolk sac antigen, and a commercially available antigen. The HA antigen agglutinated mouse erythrocytes, but it was not of value in hemagglutination inhibition tests because of "nonspecific" inhibitors in both mammalian and avian sera.

Animals↗
PubMed1979

Improved method for detecting hemagglutination by centrifugal analysis.

Centrifugal analysis can be used to detect hepatitis B surface antigen, antibody to rubella virus, and fibrin-related antigen. The procedure is performed with the same reagents used in conventional hemagglutination studies. Positive and negative reactions are distinguished by the rates of erythrocyte clearance in the centrifugal field (delta A/delta time); positive cells move more rapidly than negative cells, and this difference varies directly with the concentration of detectable antigen or antibody. This phenomenon is thought to be a result of the greater adhesion of negative cells to the cuvette's surface. Sensitivity and specificity are greater in the centrifugal analysis technique than in the more conventional hemagglutination tests. False-positive reactions are eliminated and the quantitative data are accurate and reproducible.

Antibodies↗
PubMedDate not supplied

[Determination of arbovirus group affiliation in the indirect hemagglutination reaction].

A dry polyvalent erythrocyte immunoglobulin diagnostic preparation for arboviruses of Group B may be prepared to be used in the indirect hemagglutination test. The preparation detects antigens of arboviruses of this group in the tissue culture fluid and in suckling mouse brain tissue treated with sucrose-acetone. The test with Group B arbovirus antigens is inhibited specifically by the homologous polyvalent immune gamma globulin. Inhibition of hemagglutination by species-specific immune globulins to individual members of Group B arboviruses permits typing of tick-borne encephalitis birus only. In making the erythrocyte diagnostic preparation, the optimal concentration of the sensitizing immune gamma globulin should be determined experimentally.

Animals↗
PubMedDate not supplied

[Indirect hemagglutination test for indicating the HFRS virus and the laboratory diagnosis of the disease].

Conditions have first been developed for the preparation of erythrocyte immunoglobulin diagnostic preparation of erythrocyte immunoglobulin diagnostic preparation for HFRS virus which permits express detection of the specific virus antigen in suspensions of the lung tissue of rodents by means of the indirect hemagglutination test (IHA) and laboratory diagnosis of the infection in humans by means of antibody detection by the indirect hemagglutination-inhibition test (IHAI). The IHA test is as sensitive as immunofluorescence, while the sensitivity of the IHAI test is not inferior to that of immunofluorescence but is higher than that of RIA.

Animals↗
PubMed1980

Hemagglutination by canine parvovirus: serologic studies and diagnostic applications.

Conditions for canine parvoviral hemagglutination (HA) and hemagglutination-inhibition (HI) reactions were defined. The HA phenomena were used to differentiate canine parvovirus (CPV) from feline panleukopenia virus (FPV), mink enteritis virus (MEV), and minute virus of canines. Serologic comparisons of the CPV, FPV, and MEV by HA-HI and serum-neutralization tests indicated that CPV, FPV, and MEV were antigenically similar but were different from minute virus of canines. Diagnostic application of HA tests to fecal samples from acute cases of enteritis was discussed. Combinating HA tests with HI tests on fecal samples provided a rapid and specific diagnostic method for CPV infection. Secular seroprevalence studies indicated the emergence of CPV infeciton in the United States dog population-at-large in 1978.

Animals↗
PubMedDate not supplied

[Experience with using the indirect hemagglutination reaction in studying natural foci of tick-borne encephalitis].

Using the indirect hemagglutination test, tick-borne encephalitis (TBE) virus could be detected in the nutrient medium of the infected cell cultures, in brain suspensions of the infected suckling mice and in most specimens of suspensions of Ixodid ticks containing active virus. Positive results were obtained only with erythrocyte immunoglobulin diagnostic preparation to TBE virus but not with the diagnostic preparation for Omsk hemorrhagic fever. In the indirect hemagglutination inhibition test sera from human patients similarly inhibited antigens of tick-borne encephalitis and Omsk hemorrhagic fever.

Animals↗
PubMed1980

A simple technique for quantitative measurement of erythrocyte settling patterns in hemagglutination inhibition tests for immunologic hormone assay.

A simple technique for direct quantitative evaluation of hemagglutination or hemagglutination inhibition tests used in immunologic proteo-hormone assay systems is described. The test is performed in calibrated glass capillaries (internal diameter 2.5...4 mm) at horizontal position. After sedimentation the non-agglutinated erythrocytes form two fine parallel stripes along the bottom of the capillaries. The distance between the stripes depends on the amount of additional free antigen brought into the system. It can be measured by the slit of a micrometer screw or a corresponding equipped microscope and might be used as y-variable for drawing calibration curves. At well standardized test conditions and for selected concentration ranges coefficients of variation between 10 and 15% can be achieved. So quantitative determinations can be made without serial sample dilutions to be prepared, covering concentrations ranges between 1 to 10.

Chorionic Gonadotropin↗
PubMed1976

Detection of Moraxella bovis antibodies in infectious bovine keratoconjunctivitis by a passive hemagglutination test.

A passive hemagglutination test was developed to detect antibody response to Moraxella bovis in tears. Tannic acid-treated sheep erythrocytes were sensitized with sonicated antigen prepared from M bovis cultures. The test was found to be a relatively simple, specific, and reliable procedure for titrating antibodies in lacrimal secretions. The hemagglutination test could be a valuable method for seroepizootiologic investigation of infectious bovine keratoconjunctivitis.

Animals↗
PubMed1996

Correlation between ELISA, hemagglutination inhibition, and neutralization tests after vaccination against tick-borne encephalitis.

The significance of IgG antibody levels determined by a binding assay (ELISA) was investigated as a surrogate marker for the presence of neutralizing and hemagglutination inhibiting antibodies in sera from individuals vaccinated against tick-borne encephalitis (TBE). To assess the extent of interference by flavivirus cross-reactive antibodies, sera from persons with a proven or suspected history of other flavivirus infections and/or vaccinations were also examined. An excellent and highly significant correlation was found between ELISA IgG units and the antibody titers obtained by the hemagglutination inhibition (HI) as well as by the neutralization test (NT), provided that there was no other exposure to flavivirus antigens except TBE vaccination. Yellow fever vaccination and/or dengue virus infections induced significant levels of antibodies reactive in the TBE ELISA and HI test, which did not exhibit, however, neutralizing activity against TBE virus. The phenomenon and problem of "original antigenic sin" was demonstrated in a TBE vaccinee with a history of previous flavivirus infections. TBE vaccination first induced a booster reaction resulting in a rise in the level of cross-reactive antibodies only, whereas TBE virus-neutralizing antibodies became detectable only after the third vaccination. It is concluded that the level of IgG antibodies determined by ELISA is a good marker for predicting the presence of neutralizing antibodies after TBE vaccination, but only in the absence of flavivirus cross-reactive antibodies. Otherwise, a neutralization assay is necessary for assessing immunity.

Animals↗
PubMed2001

Role of C-terminal region of HA-33 component of botulinum toxin in hemagglutination.

Using SDS-PAGE, we found that one subcomponent, hemagglutinin (HA-33), from the Clostridium botulinum progenitor toxin of type D strain 1873 and type C strain Yoichi had slightly smaller molecular sizes than those of type C and D reference strains, but other components did not. Based on N- and C-terminal sequence analyses of HA-33, a deletion of 31 amino acid residues from the C-terminus at a specific site was observed in the HA-33 proteins of both strains. The progenitor toxins from both strains showed poor hemagglutination activities, titers of 2(1) or less, which were much lower than titers from the reference strains (2(6)), and did not bind to erythrocytes. These results suggest strongly that the short C-terminal region of the HA-33 plays an essential role in the hemagglutination activity of the botulinum progenitor toxin. Additionally, a sequence motif search predicted that the C-terminal region of HA-33 has a carbohydrate-recognition subdomain.

Amino Acid Sequence↗
PubMed1995

Murray valley encephalitis virus envelope protein antigenic variants with altered hemagglutination properties and reduced neuroinvasiveness in mice.

Neutralization escape variants of Murray Valley encephalitis virus were selected using a type-specific, neutralizing, and passively protective anti-envelope protein (E) monoclonal antibody (4B6C-2) which defines epitope E-1c. Nucleotide sequence analysis revealed single nucleotide changes in the E genes of 15 variants resulting in nonconservative amino acid substitutions in all cases. One variant had a three-nucleotide deletion in the E gene which resulted in loss of serine at residue 277. Changes were clustered into two separate regions of the E polypeptide (residues 126-128 and 274-277), indicating that E-1c is a discontinuous epitope. One variant (BHv1), altered at residue 277 (Ser-->Ile), failed to hemagglutinate across the pH range 5.5-7.5, in contrast to parental virus and the other escape variants which hemagglutinated at an optimal pH of 6.6. BHv1 was also of reduced neuroinvasiveness in 21-day-old mice following intraperitoneal inoculation compared to the other viruses. Parental virus and the neutralization escape variants grew equally well in both vertebrate and invertebrate cell cultures, indicating that the reduced neuroinvasiveness of BHv1 was not due to a major abnormality of replication.

Amino Acid Sequence↗
PubMed1983

Partial isolation and characterisation of a hemagglutinating factor from avocado seed.

Extracts of ground avocado seeds (Fuerte and Hass varieties), prepared in different buffer solutions (pH 2.0-12.0), show hemagglutinating activity towards A, B, AB, and H (0) human erythrocytes. The extract showing the highest titer of aggulination was extracted at pH 10.5. The crude extract also causes hemolysis of fresh washed erythrocytes. The hemagglutinating factor is not inhibited by most of the simple sugars tested, e.g., D-glucose, D-mannose, D-galactose, and glucose-amine. The only sugars which show some inhibitory effect are N-Acetyl-neuraminic acid, melibiose, and stachiose. Basic amino acids, e.g., lysine and arginine also inhibit its activity. However the most potent inhibitors of the agglutinin are proteins and glycoproteins such as bovine serum albumin, collagen, thyroglobulin, ovalbumin, mucin, and fetuin. The agglutinin is adsorbed on polymer beads such as Sepharose 4B, Sephadex G100, Agarose, and Chitin, and it reacts with hog erythrocyte membranes. It can be partially eluted from those materials with alkaline buffers (pH 9.0-10.5).

Animals↗