Haemagglutinin activity in the haemolymph of individual Acrididae (grasshopper) specimens

Twenty-four individual grasshopper specimens representing four Melanoplus spp. contained similar broad-spectrum haemolymphatic haemagglutinin. The agglutinin activity showed highest titre toward human ABO and rabbit cells among nine types of erythrocytes tested. Titre values differed between individual insects but agglutination specificity toward different erythrocytes was similar. Agglutination of type-O red cells by individual grasshopper haemolymph was inhibited by 34 of 41 tested carbohydrates, carbohydrate derivatives, alcohols and chelating agents. Individual insects showed similar patterns of haemagglutination inhibition. Non-inhibitory compounds were mannose and mannose derivatives (excepting N-acetylneuraminate), several glucose derivatives, amino sugars and ethanol. The observations indicated that haemolymph from an individual grasshopper contained complex heteroagglutinin activity similar to that found in haemolymph pooled from several insects. Determination of minimal effective inhibitor concentrations confirmed the presence of heteroagglutinin activity primarily directed toward galactose and glucose and related α-linked glycosidic derivatives.     

Surface haemagglutinating activity of Pseudomonas aeruginosa

Intact cells of several strains of Pseudomonas aeruginosa agglutinate papain-treated human erythrocytes. The agglutinating activity appears to reside in the surface layers of the bacterium-Pseudomonas surface haemagglutinin. This activity does not correlate with the existence of the internal PA-I and PA-II lectins, the presence of fimbriae or adherence to human buccal epithelial cells. Disruption of the bacterial cells by sonication abolishes their haemagglutinating activity. The intact cells of P. aeruginosa are also able to agglutinate rabbit, chicken, dog, guinea pig and sheep erythrocytes. This activity is generally higher with papain-treated erythrocytes, except those of rabbit in which lower haemagglutinating activity is observed after papain treatment. Optimal conditions for the haemagglutination are 37 degrees C and pH 6-7. Simple sugars do not inhibit, while fetuin and hydrophobic amino acids inhibit this activity. Exposure of the bacterial cells to proteolytic enzymes, EDTA or denaturating conditions abolish the haemagglutinating activity. These results indicate that the surface haemagglutinin is a protein which agglutinates red blood cells via hydrophobic interactions.     

Differential affinity of natural haemagglutinin of Macrobrachium rosenbergii towards vertebrate erythrocytes: effect of sex, size and moult stage on haemagglutination titre

Lectins play important role in innate immunity of animals. The affinity of the natural haemagglutinin of the giant freshwater prawn Macrobrachium rosenbergii towards vertebrate erythrocytes and its level with relation to sex, size and moult stages were studied. The strongest agglutinating titres in haemolymph of prawns were marked against guinea pig, chicken, Clarias batrachus, and rabbit erythrocytes, and the weakest towards cattle, dog, horse and goat erythrocytes. A moderately agglutinating titre was evident in duck and human erythrocytes. The haemolymph of adult, male or intermoult stage prawns weighing more than 100 g had the highest haemagglutinating activity as compared to their respective counterparts with varied responses observed towards various erythrocytes.     

Natural lectin activity in the haemolymph of Panstrongylus megistus (Heteroptera: Reduviidae)

The haemolymph of Panstrongylus megistus showed a natural lectin activity for a wide range of vertebrate erythrocytes. Agglutination was observed against all vertebrate erythrocytes tested (human ABO, duck, rabbit, mouse, sheep, chicken and cow). Cow erythrocytes showed the lowest titre. Concerning human erythrocytes, the lectin activity was similar in the types A+, B+ and AB+ while the highest activity was observed in the type O+. Determination of minimal inhibitory concentrations was carried out with human erythrocytes type O+. Agglutination was inhibited by several carbohydrates (rhamnose, D-galactose, raffinose, D-lactose and D-fucose). Rhamnose was reported as the strongest inhibitor (0.78 mM). The results suggest the presence of more than one lectin in the haemolymph of P. megistus.     

Proteins with haemagglutinin activity in larvae of the Colorado beetle, Leptinotarsa decemlineata

The haemagglutinating activity of larval haemolymph of Leptinotarsa decemlineata against red blood cells of various origins has been examined. This activity appeared to be unspecific, since all the different types of erythrocytes were agglutinated by a haemolymph dilution of $\text{1}\text{128}$ to $\text{1}\text{512}$. Only horse erythrocytes were agglutinated to a greater degree ($\text{1}\text{3200}$. Red blood cells became much more sensitive after treatment with trypsin, while formol fixation also resulted in a better agglutinability. Sulphated polysacchrides (heparin, mucin, dextran sulphate) were good inhibitors of the haemagglutination reaction. A weaker inhibition was obtained with hexosamines. As demonstrated by immunoelectrophoresis, two haemagglutinins occur in larval haemolymph. One is specific for larvae and pupae, and is therefore called the larval-pupal haemagglutinin. It is absent in adults. The second haemagglutinin is the well-known chromoprotein 2, which is present in all developmental stages, including the egg, where it constitutes an important element of yolk proteins. The affinity of chromoprotein 2 toward dextran sulphate was confirmed by precipitation tests in agarose.     

A New Lectin from Meadow Saffron (Colchicum automnale)

A lectin has been isolated from tubers of the meadow saffron (Colchicum autumnale). It is an octameric protein (M_r 100,000) composed of 4A- and 4B-subunits of M_r 15,000 and 10,000, respectively. It is a glycoprotein with 4.4% carbohydrate, the main sugars are (N-acetyl-) glucosamine, mannose, fucose, and xylose. Although the Colchicum autumnale agglutinin (CAA) agglutinates human red blood cells, it has a much higher activity with rabbit erythrocytes. With respect to its carbohydrate-binding specificity CAA behaves rather unusually as it is inhibited by lactose, galactose, N-acetylgalactosamine and related sugars when assayed with human red blood cells but not in assays with rabbit erythrocytes.     

Size-dependent haemagglutinating activity in the haemolymph from sub-adult blue shrimp (Penaeus stylirostris stimpson)

• 1.1. The blue shrimp (Penaeus stylirostris) haemolymph is capable of agglutinating the red blood cells of several vertebrates to different titres. However, the haemagglutinin is considered non-specific because it is incapable of differentiating erythrocytes of human blood types A, B and O.
• 2.2. Haemagglutinating activity and serum protein content were determined for male and female blue shrimp ranging in size from 8.5 to 16 cm. Haemagglutinating activity decreased significantly with animal size, while protein content was unaffected.
• 3.3. The above finding is probably related to maturation of the immune system and could explain the higher susceptibility of young shrimp to parasitic and viral diseases.

     

Carbohydrate-binding specificities of anti-erythrocyte lectins (haemagglutinins) in Anopheles gambiae gut extracts and haemolymph

Lectins that agglutinate red blood cells (RBC) were demonstrated in Anopheles gambiae mosquito haemolymph and gut extracts. No apparent differences in haemagglutinin titres were detected between male and female mosquitoes and overall agglutinin levels were not increased following a bloodmeal. Titres were highest in the haemolymph and midgut extracts versus human AB, horse, chicken and goat RBCs and in hindgut against human AB, chicken and sheep; foregut extract gave relatively low titres. Adsorption of haemolymph and gut extracts with selected RBCs coupled with carbohydrate inhibition and the use of enzyme-treated RBCs revealed the presence of multiple (hetero-) agglutinins. An.gambiae lectins were specific for (1-1)-, (1-4)- or (1-6)-linked glucose based disaccharides, glucose and its (1-2) or (1-3) linkages with fructose and, to a lesser extent, aminated or N-acetylated glucose, or galactose and its deoxy derivatives. This study presents the first report of the occurrence of heterogenous anti-RBC agglutinins in haemolymph and gut extracts of the mosquito An.gambiae, together with the sugar-binding specificities of these lectins.     

Hemagglutinin specificity of Cl. botulinum types A, B, and F in reaction with erythrocytes of various animals]

The following differences were revealed in the haemagglutination reaction with the erythrocytes of man, sheep, rabbit, chicks and mice between the haemagglutinins of Cl. botulinum, types A, B and F, having a close affinity with one another: haemagglutinin of type A actively reacted with the erythrocytes of man, sheep, rabbit, rats and chicks; haemagglutinin of type B reacted only with the erythrocytes of man and rabbits; haemagglutinin of type F failed to react with any of the types of the erythrocytes tested; only with the use of erythrocytes treated with neuraminidase was it possible to establish the presence of haemagglutinin fraction in Cl. botulinum, type F. Treatment of human erythrocytes with neuraminidase and proteolytic enzymes caused a marked increase in the sensitivity of the haemagglutination reaction in haemagglutinins of Cl. botulinum, types A, B and F.     

Haemagglutinin production by enterotoxigenic strains of Clostridium perfringens type A

Thirty-nine enterotoxigenic cultures of Clostridium perfringens type A were studied for enterotoxin and haemagglutinin production. Enterotoxin was quantitated by sandwich ELISA and DOT-ELISA techniques and haemagglutinin titres were determined using sheep and human erythrocytes. Haemagglutinins from only six cultures reacted against both sheep and human erythrocytes; a further 13 reacted only against human erythrocytes, and another five only against sheep cells.The authors are with the Department of Veterinary Public Health and Epidemiology, Ranchi Veterinary College, Birsa Agricultural University, Ranchi-834007 (Bihar), India.     

Identification of thymus-dependent areas in frozen sections of guinea pig lymphatic tissue by adherence of rabbit erythrocytes

Untreated rabbit erythrocytes adhere to thymus-dependent areas of guinea pig lymphatic tissues as shown with frozen sections. The adherence reaction is temperature dependent. Optimal results were obtained by incubation of the tissue section with the erythrocytes at temperatures between 0 ° and 4 °C. At 37 °C no adherence of erythrocytes was observed. Out of other erythrocytes tested (human, sheep, chicken, rat, mouse) only rat and mouse cells showed weak adherence to guinea pig thymus sections.     

Isolation and characterization of a zinc-containing metalloprotease expressed by Vibrio tubiashii

A Vibrio tubiashii hemagglutinin, a protease, was purified by ammonium sulfate precipitation, gel filtration, and hydrophobic interaction chromatography. It agglutinates sheep, chicken, bovine, rabbit, guinea pig, and human erythrocytes. It has a molecular mass of 35 kDa, isoelectric points of 3.5 and 3.7, and is inhibited by ortho-phenanthro line, phosphoramidon, and Zincov. The N-terminal amino acid sequence (Ala-Gln-Ala-Thr-Gly-Thr-Gly- Pro-Gly-Gly-Asn-Gln-Lys-Thr-Gly-Gln- Tyr-Asn-Phe-Gly) has strong homology to other Vibrio proteases.     

Haemagglutinin of the antarctic seaweed Georgiella confluens (Reinsch) Kylin: isolation and partial characterization

The marine red alga Georgiella confluens collected from Mackellar Inlet, King George Island, South Shetland Islands, Antarctic, was used in the isolation of a protein with agglutinating activity. The Georgiella confluens haemagglutinin (GCH) was extracted with 20 mM phosphate buffer, pH 7.0, and purified through ion exchange chromatography, followed by affinity chromatography on immobilized porcine stomach mucin. Among the erythrocytes analysed (human A, B and O groups, rabbit and chicken), GCH agglutinated specifically chicken erythrocytes. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis of the haemagglutinin revealed a single band of 21.5 kDa, while by gel filtration on Sephadex G-100 its native molecular mass was 25.5 kDa, suggesting that GCH is a monomeric protein. Haemagglutination studies showed that the GCH activity was stable through temperature variations and did not exhibit divalent cation dependence. Furthermore, the haemagglutinin was inhibited by the complex glycoproteins of porcine stomach mucin and fetuin, whereas the mono-, di-, and trisaccharides tested showed no effect.     

Blood group B-specific lectin of Plecoglossus altivelis (Ayu fish) eggs

A lectin that agglutinates human blood group B erythrocytes but not blood group A and O erythrocytes was isolated from eggs of Ayu sweet fish (Plecoglossus altivelis). The lectin also agglutinates Ehrlich ascites carcinoma cells but not rat ascites hepatoma AH109 or rat sarcoma 150 cells tested. The lectin agglutination was most effectively inhibited by monosaccharides with the first type of configuration, i.e., L-rhamnose, L-mannose and L-lyxose at a concentration of 0.03 mM. The lectin agglutination was moderately inhibited by monosaccharides with the second type of configuration, i.e., D-galactose, D-fucose and D-galacturonic acid at a concentration of 0.4 mM. However, the agglutination was not inhibited by various other monosaccharides and oligosaccharides that have other types of configuration. The basis for an apparent B-specific hemagglutination may be due to the steric similarity of the C₂ and C₄ of the galactosyl series, the B-specific determinant, and the L-rhamnosyl series, which are the best inhibitors of the lectin activity. The lectin was affinity purified on an L-rhamnosyl-Sepharose column and was characterized as a homogeneous low molecular weight protein (M_r 14 000) with an abundance of hydrophobic amino acids and dicarboxylic amino acid.     

Hemagglutinins in brown seaweeds

Twenty-eight brown seaweeds contain agglutinins that show activity against animal and human erythrocytes. Three brown seaweeds are described whose hemagglutinic activity has not been previously reported: Ectocarpus confervoides, Giffordia granulosa and Cutleria multifida. Hemagglutinic activity against different erythrocytes is as follows: rabbit, 100%; sheep, 71%; chicken, 64%; guinea-pig, 39%; human, 38%; horse, 25% and calf, 21%. The highest agglutinic activity was found with rabbit erythrocytes, with maximum titres of: Fucus serratus (2¹⁸), Laminaria saccharina (2¹⁷) and Himanthalia elongata (2¹⁷). The species Giffordia granulosa showed certain specificity against human erythrocytes. In general, the hemagglutinic activity of these brown seaweeds seems to be of a polyphenolic nature. Agglutinic activity of some of these brown seaweeds can be used as a taxonomic index.     

Haemagglutinating and antibiotic activities of freshwater microalgae

We analysed the haemagglutinating activity of algal extracts from 44 species of freshwater microalgae against native and trypsin/papain-treated cow, pig, sheep, and human A-, B-, and O-type erythrocytes. Algal extracts obtained with aqueous ethanol exhibited higher haemagglutinating activity than those obtained with aqueous acetone. Most of the algal extracts agglutinated at least one of the erythrocyte types analysed. Human erythrocytes were the most sensitive of the cell types analysed. In the other species, the sensitivity of algal haemagglutinating activity for erythrocytes was pig > sheep > cow. Pre-treating erythrocytes with trypsin and papain improved the detection of most algal agglutinins and increased the haemagglutination titre; pre-treatment with papain was most effective for pig erythrocytes. Algal extracts stored at –20 °C for 4 months lost their haemagglutinating activity. Algal extracts also exhibited strong antibiotic activity against food pathogenic bacteria, especially against Bacillus. Our numerical taxonomy data showed that these microalgae might be grouped into several clusters according to their haemagglutinating activity. The detection of haemagglutinating activity may provide an efficient biochemical or physiological character to classify and differentiate microalgae. Our results suggest that freshwater microalgae might provide a potent source of haemagglutinins and antibacterial compounds for biochemical and medical studies and applications.     

Existence of a Novel Hemagglutinin Having No Protease Activity in Vibrio mimicus

The protease elaborated by Vibrio mimicus is known to possess hemagglutinating ability to chicken erythrocytes, the well-known HA/protease. A non-protease hemagglutinin (HA) with strong agglutinating ability towards rabbit erythrocytes was obtained from 32 hr culture supernatant of a pathogenic environmental strain of V. mimicus. This HA (V. mimicus HA: VMHA) appeared stable at relatively higher temperature and agglutinated the erythrocytes from rabbit, guinea pig and mouse but not the erythrocytes from chicken, bovine, horse and sheep. Simple sugars, metal ions and chelating agents failed to inhibit the activity of VMHA. The activity of VMHA was found to be sensitive to digestion by proteolytic enzymes including HA/protease. These results provide evidence for the existence of novel HA other than HA/protease in V. mimicus.     

A mitogenic agglutinin from the red alga Carpopeltis flabellata

An agglutinin has been isolated from the marine red alga Carpopeltis flabellata by ammonium sulphate fractionation, affinity chromatography on a yeast mannan-Sepharose 4B column and gel permeation HPLC. This new protein, designated carnin, is a monomeric glycoprotein with a M_r of 25 000, and it contains large amounts of Gly and Asx. It strongly agglutinated untreated rabbit, mouse and horse erythrocytes, and very weakly untreated human erythrocytes, whereas it did not agglutinate untreated sheep and chicken erythrocytes. Treatment of the erythrocytes with trypsin affected their sensitivity to haemagglutination by the agglutinin. The haemagglutinating activity was inhibited only by glycoproteins with N-glycosidic sugar chains. The activity was not affected by divalent cations. Carnin also showed mitogenic activity for T lymphocytes from mouse spleen. It inhibited the normal embryonic development of marine invertebrates.     

Purification and properties of a lectin from lonchocarpus capassa (apple-leaf) seed

A lectin has been purified from L. capassa seed by ammonium sulphate fractionation and affinity chromatography on a column of D-galactose-derivatized Sepharose. The lectin is a glycoprotein which contains 3.8% neutral carbohydrates comprised of mannose, N-acetylglucosamine, xylose and fucose. The subunit M, of the lectin is 29 000, it has only alanine as N-terminal amino acid and contains 240 amino acids with a high content of acidic and hydroxy amino acids, single residues of methionine and histidine and the absence ofcystine. The lectin of L. capassa seed is a metalloprotein in that it contains 0.8 mol Ca²⁺ and 0.4 mol Mn²⁺ per mol. It agglutinates untreated human A, O and B type erythrocytes and rabbit erythrocytes. N-Acetyl-D-galactosamine was the best inhibitor. D-Galactose and various carbohydrates containing this sugar inhibit the hemagglutinating activity of the lectin. The lectin is also inhibited by D-glucose. The amino-terminal sequence of the lectin from L. capassa seed shows a significant degree of homology with many lectins from leguminous plants and is related to concanavalin A by a circularly permuted sequence homology.     

Spontaneous lytic activity against heterologous erythrocytes in cotton rat (Sigmodon hispidus) serum

Although innate immunity has been well studied in laboratory animal models, no such documentation exists for wild species possessing a diversity of physiological adaptations to their environment. We examined the blood sera of 188 hispid cotton rats (Sigmodon hispidus) for naturally occurring hemolytic activity against heterologous erythrocytes. Ninety-two percent of the blood sera samples from cotton rats lysed sheep erythrocytes. All sera tested against chicken erythrocytes showed hemolytic activity, while only 44% of the same sera could lyse bovine erythrocytes. No hemolytic activity was present in cotton rat sera against erythrocytes from other rodent species (Eastern woodrat, Neotoma floridana, and pine vole, Microtus pinetorum). Hemolytic activity was heat labile and appeared to be mediated through the classical complement pathway. The protective nature of this hemolytic factor is unclear but it is probably directed at a more relevant molecule. These data, along with other reports of naturally occurring target specific serum factors in the cotton rat, may reflect the importance of innate protective mechanisms to small mammal populations.