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PubMed1986

Immunochemical studies on the combining site of the blood group A-specific lima bean lectin.

The combining site of the lima bean (Phaseolus lunatus) lectin (LBL) was studied by quantitative precipitin and precipitin-inhibition assays. The lectin precipitated best with hog gastric mucosa and human ovarian cyst blood group A1 substances and moderately with A2 substances. B substances precipitated very poorly and H, Lea, Leb, and precursor I substances did not react. Blood group A1 and A2 substances reacted to varying extents and these differences are attributable to heterogeneity resulting from incomplete biosynthesis of carbohydrate chains. By inhibition of precipitation of LBL with A1 blood group substance, the lectin was found to be most specific for fucose-containing oligosaccharides having the A trisaccharide, DGalNAc alpha 1----3[L-Fuc alpha 1----2]DGal determinant. The best inhibitor, an A-specific hexasaccharide, DGalNAc alpha 1----3[LFuc alpha 1----2]DGal beta 1----3DGlcNAc beta 1----3-DGal beta 1----4DGlc, was 11 times more active than the A trisaccharide. A difucosyl oligosaccharide with a second fucose linked alpha 1----3 to the DGlcNAc is less active; fucose linked alpha 1----4 to DGlcNAc was completely inactive. These results suggest that specific interactions with the subterminal sugars may be important in the binding, and that the specificity of the lectin combining site involves at least the nonreducing terminal four and probably five sugars of the hexasaccharide. Thus LBL has a more-extended binding site than was inferred previously and is in the upper range of antibody combining-site sizes.

ABO Blood-Group System↗
PubMed1998

Studies on the binding of wheat germ agglutinin (Triticum vulgaris) to O-glycans.

The binding profile of Triticum vulgaris (WGA, wheat germ) agglutinin to 23 O-glycans (GalNAc alpha1-->Ser/Thr containing glycoproteins, GPs) was quantitated by the precipitin assay and its specific interactions with O-glycans were confirmed by the precipitin inhibition assay. Of the 28 glycoforms tested, six complex O-glycans (hog gastric mucins, one human blood group A active and two precursor cyst GPs) reacted strongly with WGA and completely precipitated the lectin added. All of the other human blood group A active O-glycans and human blood group precursor GPs also reacted well with the lectin and precipitated over two-thirds of the agglutinin used. They reacted 4-50 times stronger than N-glycans (asialo-fetuin and asialo-human alpha1 acid GP). The binding of WGA to O-glycans was inhibited by either p-NO2-phenyl alpha,betaGlcNAc or GalNAc. From these results, it is highly possible that cluster (multivalent) effects through the high density of weak inhibitory determinants on glycans, such as GalNAc alpha1-->Ser/Thr (Tn), GalNAc at the nonreducing terminal, GlcNAc beta1--> at the non-reducing end and/or as an internal residue, play important roles in precipitation, while the GlcNAc beta1-->4GlcNAc disaccharide may play a minor role in the precipitation of mammalian glycan-WGA complexes.

Carbohydrate Sequence↗
PubMed1998

Evaluation and treatment of allergic fungal sinusitis. I. Demographics and diagnosis.

BACKGROUND: Few cases of allergic fungal sinusitis have been systematically evaluated to conclusively confirm working clinical, histopathologic, and serologic diagnostic criteria. OBJECTIVES: The objective of this study was to describe 67 consecutive cases of allergic fungal sinusitis, the largest number of cases yet published. METHODS: Cases from 1 practice over 8 years were evaluated with a consistent protocol, including skin testing, serum chemistries and serologies, and surgical specimen analysis. RESULTS: All patients were atopic (100 %) and had nasal polyposis (100%). They tended to be young (33.3+/-13.1 years, mean +/-SEM), immunocompetent (92 %; remaining 8 % with low quantitative immunoglobulin but normal function), have slight female preponderance (58%), have a history of hypertrophic rhinosinusitis (100%), report nasal cast production (75%), and have developed their disease in the southwestern United States. Bipolaris spicifera was the most prevalent fungus involved (67%). Total serum IgE (mean 668 IU/mL) and fungal-specific IgG were generally elevated, whereas fungal-specific precipitins and specific IgE were generally negative despite positive fungal-specific immediate hypersensitivity skin tests. CONCLUSIONS: Patients with allergic fungal sinusitis tend to have elevated total serum IgE and fungal-specific IgG at diagnosis but not fungal-specific IgE or precipitins. Histopathologic criteria for allergic fungal sinusitis diagnosis are discussed. The southwestern United States appears to be a "hot spot" for the disease, particularly caused by B spicifera.

Adult↗
PubMed1988

Immunogenic and antigenic characteristics of Salmonella heat-labile enterotoxin.

The intramuscular immunization of rabbits with enterotoxin of S. weltevreden failed to provide protection against challenges with homologous Salmonella enterotoxin as well as heterologous enterotoxins (cholera toxin or E. coli LT). Similar results were obtained in rabbits immunized with cholera toxin, choleragenoid and E. coli LT. However, Salmonella antitoxin contained neutralizing antibodies against Salmonella enterotoxin (but not against cholera toxin) and thus was capable of neutralizing Salmonella enterotoxin when tested for skin permeability reaction. Immunodiffusion experiments showed that antitoxin prepared against the enterotoxin of one of the strains of S. weltevreden formed precipitin bands with enterotoxin preparations of 5 strains of S. weltevreden and 2 strains of S. anatum. However, Salmonella antitoxin failed to form precipitin bands with enterotoxins of other heterologous Salmonella species (S. dublin, S. enteritidis, S. hindmarsh and S. newport), cholera toxin and E. coli LT. The immunoelectrophoretic studies corroborated the results obtained by double immunodiffusion experiments. However, both Salmonella and cholera toxins migrated electrophoretically toward the cathode and resembled globulin in this respect. Salmonella enterotoxin, though immunogenic, yet proved unprotective through the parenteral route and appears to be antigenically distinct from cholera and E. coli enterotoxins.

Animals↗
PubMed1990

Immunochemical characterization of type i carbohydrate antigen of "Streptococcus milleri" (Streptococcus anginosus).

Type-specific carbohydrate antigen of the serotype i "Streptococcus milleri" was extracted with trichloroacetic acid from purified cell walls of the type strain K39K. The extracts were then purified by chromatography on DEAE-Sephadex A-25 and Sephadex G-100 columns. The purified serotype i carbohydrate antigen produced a single precipitin band against its homologous type-specific antiserum, which fused with the band produced by the autoclaved extract of the type strain cells. The serotype i antigen was a polysaccharide composed of rhamnose, galactose and glucose in a molar ratio of 1.6:6.8:1.0. The quantitative precipitin inhibition test with various haptenic sugars showed that galactose as well as lactose produced the greatest inhibition, which suggested that a galactose in terminal beta linkage is the immunodeterminant of the serotype i-specific antigen. Galactose was detected in the autoclaved extracts from cells of all the 15 serotype i strains tested.

Antigens, Bacterial↗
PubMed2006

Contemporaneous occurrence of allergic bronchopulmonary aspergillosis, allergic Aspergillus sinusitis, and aspergilloma.

BACKGROUND: The clinical categories of Aspergillus-related respiratory disorders usually remain mutually exclusive. The coexistence of allergic bronchopulmonary aspergillosis (ABPA) with aspergilloma is uncommon, whereas concurrent ABPA and allergic Aspergillus sinusitis (AAS) is rare. The association of these 3 clinical entities has previously been documented only once in a patient who had earlier been operated on for an aspergilloma before the diagnoses of ABPA and AAS were established. OBJECTIVE: To describe an adult in whom ABPA, AAS, and aspergilloma were diagnosed simultaneously. METHODS: Spirometry, radiography, computed tomography, skin allergy testing with Aspergillus antigens, serum precipitins against Aspergillus, total and specific IgE, functional endoscopic sinus surgery, and fungal culture were performed. RESULTS: A 26-year-old man who had asthma and rhinitis since childhood presented with hemoptysis. Serial chest radiographs revealed transient pulmonary infiltrates and an aspergilloma. Computed tomography of the thorax confirmed the aspergilloma and showed bilateral central bronchiectasis along with patchy infiltrates. Strong bands of precipitins were detected against Aspergillus fumigatus, and intradermal testing with Aspergillus antigens elicited strong type I and III hypersensitivity reactions. Specific IgE and IgG antibodies against A fumigatus were positive, and total IgE levels were significantly elevated. Peripheral blood eosinophilia was also detected. Sinus involvement was confirmed on computed tomography, and pathologic material obtained by functional endoscopic sinus surgery demonstrated allergic mucin that contained fungal elements. In addition, A fumigatus was cultured. CONCLUSIONS: ABPA, AAS, and aspergilloma can occur simultaneously in the same patient.

Adult↗
PubMed2003

Correlations of anti-dsDNA and anti-ribosomal P autoantibodies with lupus nephritis.

Patients with systemic lupus erythematosus, with and without nephritis, were studied for their serological profiles. Patients were stratified into two groups defined by the presence or the absence of precipitating antibodies to ribosomal P proteins. It was found that 27 patients were positive for anti-P precipitins and the remaining 34 patients were studied for the presence of lesser amounts of anti-P antibodies by Western blot and ELISA tests. The nephritic patients were characterized most frequently by the presence of both autoantibodies to dsDNA and the ribosomal P proteins. In the group with anti-P precipitins, anti-dsDNA titers were much higher in the patients with nephritis than in those without nephritis. Thus, over a wide range of anti-ribosomal P antibody concentrations, the mutual occurrence of anti-P antibodies with anti-dsDNA antibodies was strongly associated with lupus nephritis.

Autoantibodies↗
PubMed1978

Studies with Brugia pahangi. 16. Precipitation antibody in infected cats detected by counterimmunoelectrophoresis.

In cats infected with normal, or irradiated, infective (L3) larvae of Brugia pahangi counterimmunoelectrophoresis revealed the presence of antibody to soluble antigens derived from microfilariae, adults and infective larvae of the same parasite. Infected cats with a persistently high to moderate microfilaraemia gave positive precipitin reactions to L3, microfilarial and adult worm antigens. Cats which had become amicrofilaraemic had antibody to L3 and microfilarial antigens but not to adult worm antigen. Serum from cats inoculated with irradiated L3 larvae produced a precipitin reaction only to the L3 antigen.

Animals↗
PubMed1984

Counter current immunoelectrophoresis, a new technique for the rapid serodiagnosis of porcine cysticercosis.

Counter current immunoelectrophoresis was used to detect porcine cysticercosis and water soluble extracts of scolex and of scolex with cyst wall were used as antigens. Serum samples from 40 pigs infected with Cysticercus cellulosae, five infected with C. tenuicollis and five with hydatid cysts, and 15 healthy pigs were tested. A sharp and thick concave precipitin band was observed at the point of interaction of antigen and antibody within 90 min in 39 sera from infected pigs (97.5%). The precipitin reaction was better in barbitone buffer of pH 8.6 with the well distance at 6 mm. No false or cross reaction were found and the test was rapid and sensitive.

Animals↗
PubMed1974

Antibody responses in patients with farmer's lung disease to antigens from Micropolyspora faeni.

Three purified cell-wall glycoprotein antigens, a, b and c, sensitive to sodium periodate and resistant to pronase, were extracted from mycelium of Micropolyspora faeni with aqueous phenol or trichloracetic acid. Pronase-sensitive, sodium periodate-resistant protein antigens were extracted from mycelium with aqueous phenol. Immunoelectrophoresis was a critical method of assessing purity of preparation.Antibodies to glycoprotein antigens only occurred in clinically defined cases of farmer's lung disease, whereas antibodies to protein antigens also occurred in symptomless farmers. Precipitins to a occurred in all cases of farmer's lung disease, and this antigen was isolated and purified.Fractionation of pooled sera from cases of farmer's lung disease showed that precipitins were IgG globulins, whereas latex-agglutinating antibodies were IgG, IgA and especially IgM globulins. It is suggested that farmer's lung may involve a cytotoxic type II reaction, in which glycoproteins adsorbed to tissue cells react with IgG, IgA and IgM immunoglobulins in the presence of complement, causing cellular damage.

Actinomycetales↗
PubMed1975

Antibody responses in patients with farmer's lung disease to antigens from Thermoactinomyces vulgaris.

A serological analysis of mycelial antigens of Thermoactinomyces vulgaris in immunodiffusion with human sera revealed five individual antigens. Three antigens were proteins, sensitive to pronase and soluble in phenol. Two were cationic polysaccharides, sensitive to sodium periodate, and containing glucosamine and muramic acid. Latex coated with mycelial antigens was compared with precipitin tests in detecting antibodies to T. vulgaris; the number of positive results detected by each test differed slightly, and a combination of the two tests detected the highest number. Counterimmunoelectrophoresis (CIE) was shown to be a very sensitive method for detecting precipitins, but not for their measurement. A prospective evaluation of immunodiffusion, latex agglutination and CIE as potential serodiagnostic techniques for farmer's lung disease is suggested.

Actinomycetales↗
PubMed1988

Precipitation of galactose-specific lectins by complex-type oligosaccharides and glycopeptides: studies with lectins from Ricinus communis (agglutinin I), Erythrina indica, Erythrina arborescens, Abrus precatorius (agglutinin), and Glycine max (soybean).

We have recently demonstrated that certain oligomannose and bisected hybrid type glycopeptides and bisected complex type oligosaccharides are bivalent for binding to concanavalin A and can precipitate the lectin [Bhattacharyya, L., Ceccarini, C., Lorenzoni, P., & Brewer, C.F. (1987) J. Biol. Chem. 262, 1288-1293; Bhattacharyya, L., Haraldsson, M., & Brewer, C.F. (1987) J. Biol. Chem. 262, 1294-1299]. The present results show that tri- and tetraantennary complex type oligosaccharides containing nonreducing terminal galactose residues, and a related triantennary glycopeptide, precipitate the D-galactose-specific lectins from Ricinus communis (agglutinin I) (RCA-I), Erythrina indica (EIL), Erythrina arborescens (EAL), and Glycine max (soybean) (SBA). Nonbisected and bisected biantennary complex type oligosaccharides can precipitate SBA, which is a tetrameric lectin, but not RCA-I, EIL, or EAL, which are dimeric lectins. The relative affinities of the oligosaccharides and glycopeptide were determined by hemagglutination inhibition measurements and their valencies by quantitative precipitin analyses. The equivalence points of the precipitin curves indicate that the tri- and tetraantennary oligosaccharides are tri- and tetravalent, respectively, for EIL, EAL, and SBA binding. However, the oligosaccharides are all trivalent for RCA-I binding due apparently to the larger size of the monomeric subunit of the lectin. The triantennary glycopeptide was also trivalent for RCA-I and EIL binding. Biantennary oligosaccharides with adequate chain lengths were found to be bivalent for binding to SBA; those with shorter chains did not precipitate the lectin.(ABSTRACT TRUNCATED AT 250 WORDS)

Carbohydrate Conformation↗
PubMed1997

Usefulness of a microimmunodiffusion test for the detection of Penicillium marneffei antigenemia, antibodies, and exoantigens.

Eight sera from culturally-proven cases of penicilliosis marneffei and their corresponding isolates were examined for circulating antibody(ies) and antigen, and exoantigens, respectively, using a microimmunodiffusion (MID) test. Two of the 8 sera produced strong precipitins (1-2) when reacted against control Penicillium marneffei antigen (5-week-old shaken cultures at 25 C) in the presence of control rabbit anti-P. marneffei serum. Five of the 8 sera produced a strong precipitin line when reacted against control hyperimmune serum to P. marneffei. These five sera, and one additional serum, which tested negative for antibody to P. marneffei, demonstrated the presence of antigen by reacting only against the anti-P. marneffei serum. Serological evaluations of the sera revealed that the MID test is capable of detecting antibody and antigen in AIDS patients having penicilliosis marneffei infections. Exoantigen analysis of the 8 P. marneffei isolates, which were previously identified using the conventional and time-consuming macro- and micro-morphological characteristics, showed the presence of 1 to 4 specific exoantigens in MID. With the exoantigen analysis, the identity of all of the isolates was confirmed as P. marneffei. Our studies indicated that the serological tests are useful for detecting circulating antibody and/or antigen in patients' sera, and that the exoantigen test is reliable for confirming the identity of P. marneffei cultures.

AIDS-Related Opportunistic Infections↗
PubMed1966

Purification of pig renin.

1. A new method of purification of renin is described. This method employs the following procedures: ethanol precipitation; saline extraction; precipitation of renin with 40% ammonium sulphate; precipitation of impurities with 3% ammonium sulphate at pH2.5; chromatography on DEAE-cellulose and CM-Sephadex; gel filtration on Sephadex G-100 (both normal and superfine grade); finally, starch-gel electrophoresis. 2. The final renin preparation had a specific activity 10(4) times that of the initial saline extract. 3. A single band of stained protein corresponding to the renin activity was present on starch-gel electrophoresis in the final step and a single precipitin line was obtained to this material with rabbit anti-(pig renin) serum. 4. Double diffusion in agar with rabbit anti-(pig renin) serum showed one major precipitin line, probably due to renin-anti-renin complex, and in addition two minor components.

Animals↗
PubMed1973

A comparaive study of the effects of chemical modification on the immunochemical and optical properties of human plasma low-density lipoprotein(s) and apoproteins.

1. The structure of human plasma low-density lipoprotein(s) [LD lipoprotein(s)] was investigated by several immunological and optical techniques. The effects of delipidation and of chemical modification by 3-carboxypropionylation, acetylation, diazotization and amidination were examined. A sensitive double-antibody radioimmunoassay for human LD lipoproteins is presented and is used to assess the extent of immunochemical modification. A computer best-fit analysis is used to analyse circular-dichorism (c.d.) spectra. These methods permit comparisons of the relative effects of chemical modification and delipidation of LD lipoprotein under similar experimental conditions. 2. 3-Carboxypropionylation, acetylation or diazotization produces qualitative and quantitative changes in the immunochemical properties of LD lipoprotein. Amidination causes minor changes detected by radioimmunoassay but not by double-diffusion experiments. In general, the order of effectiveness in displacing (125)I-labelled LD lipoprotein is amidinated>diazo or acetyl>3-carboxypropionyl derivatives. 3. The order of the extent of conformational alteration induced in apoLD lipoprotein and LD lipoprotein, as judged by c.d. analyses, was 3-carboxypropionylation>diazotization>acetylation or amidination. 4. Delipidation of LD lipoprotein results in immunological alterations that are qualitatively detected by antisera to LD lipoprotein. Four of five antisera to apoLD lipoprotein form precipitin lines of identity between native LD lipoprotein and apoLD lipoprotein in double-diffusion experiments. An anti-(apoLD lipoprotein) serum that forms precipitin lines of complete identity between LD lipoprotein and apoLD lipoprotein reacts differently with these two antigens in radioimmunoassay. ApoLD lipoprotein is only one-fourth to one-half as effective as LD lipoprotein, on a protein basis, in the displacement of (125)I-labelled LD lipoprotein from this anti-(apoLD lipoprotein). 5. Conformational analysis indicates that apoLD lipoprotein retains a high proportion of the structural integrity of the native lipoprotein. Delipidation induces a small decrease in the content of beta-structure and a small increase in disordered structure, without greatly affecting the alpha-helical content. Chemical modification produces more severe conformational changes of apoLD lipoprotein than of LD lipoprotein. Computer analysis of the c.d. spectra of apoLD lipoprotein indicates that addition of high concentrations of sodium decyl sulphate abolishes most of the beta-conformation concomitant with increases in alpha-helical and disordered structure. 6. There is parallelism between the alteration of the charge of LD lipoprotein and apoLD lipoprotein and the extent of immunochemical and conformational changes.

Acylation↗
PubMed1978

Purification of plasminogen activators from human seminal plasma.

Two plasminogen activators (1 and 2) were isolated from human seminal plasma by hiigh-speed centrifugation, Sephadex-gel filtration and ion-exchange chromatography. The activators were shown to be homogeneous by polyacrylamide-disc -gel electrophoresis at pH 8.3 and 4.5, and by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The molecular weights of activators 1 and 2 were estimated as 69 000 and 74 000. Their amino acid compositions are very similar, both being high in aspartic acid, glutamic acid, serine, glycine and leucine, and low in methionine, tryptophan, tyrosine, isoleucine and histidine. Activators 1 and 2 each possess 16 cysteine residues. Both activators have isoelectric points of approx. 7.0, are stable over a wide pH range at temperatures up to 60 degrees C, but lose activity at higher temperatures, particularly under very basic or acidic conditions. They are not inhibited by EDTA, Mg2+ and Ca2+ at 10 mM concentrations, but their activity decreases on addition of 10 mM-cysteine or Fe2+ and 6-aminohexanoate or sera from pregnant women. The precipitin band formed between urokinase and its antiserum is continuous with the precipitin bands formed between the seminal plasminogen activators and the urokinase antiserum. Antisera to urokinase inhibit both the activity of urokinase and the seminal plasminogen activators.

Amino Acids↗
PubMed1981

C-protein from rabbit soleus (red) muscle.

A new form of skeletal-muscle C-protein has been isolated from rabbit soleus (red) muscle. This new form of C-protein has been purified to homogeneity by a procedure similar to that used to purify C-protein from white skeletal muscle. In soleus muscle, only this new form of C-protein could be detected, whereas in psoas (white) muscle, only the previously identified form of C-protein was detected. The content of C-protein in rabbit soleus muscle is comparable with that found in psoas muscle. Other rabbit skeletal muscles composed of a mixture of fibre types contained at least two forms of C-protein. C-Protein derived from red skeletal muscle bound to myosin isolated from either red or white tissue, with maximum binding occurring at a ratio of approximately 13 microgram of red C-protein/100 microgram of myosin. Polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate indicated that C-protein isolated from red skeletal muscle has a molecular weight approx. 7% greater than that of C-protein isolated from white skeletal muscle. The amino acid content of both forms of C-protein was similar but major differences in the mol % of isoleucine and threonine were found. Antiserum against C-protein from white rabbit skeletal muscle formed a single precipitin line with rabbit C-protein on double in agar. This antiserum did not form a precipitin line when diffused against red C-protein from rabbit skeletal muscle. Also, this antiserum bound specifically to the A-band region of myofibrils isolated from psoas (white) muscle, but it did not bind to myofibrils prepared from soleus (red) muscle.

Amino Acids↗
PubMed1989

Physiochemical studies on achatininH, a novel sialic acid-binding lectin.

We have purified a sialic acid-binding lectin, achatininH, in a single step by affinity chromatography, having high affinity for 9-O-acetylneuraminic acid. The physicochemical characterization of the interaction of achatininH with bivalent metal ions and sialic acid derivatives by the use of spectrofluorimetry, spectropolarimetry and precipitin reaction is reported. From fluorescence quenching studies the binding of Ca2+ (Ka = 251 +/- 9 M-1) and of Mn2+ (Ka = 86 +/- 5 M-1) was found to be weak, but their presence is absolutely necessary for sugar binding as well as biological activity. The nature and position of the substituent group play a very important role in the binding affinity. AchatininH shows a high affinity for 9-O-acetylneuraminic acid (Ka = 1.20 x 10(3) +/- 0.07 x 10(3) M-1) compared with that for the 4-O-acetyl derivative. In oligomers the binding strength increases in the order monosaccharide less than disaccharide less than trisaccharide. The binding affinity of achatininH for the disaccharide was found to reach a peak around pH 8. From c.d. spectral studies achatininH was found to have a high beta-sheet content (46%) and a low alpha-helix content (24%). From precipitin analysis at least one sugar-binding site on each of the 16 monomer subunits of the protein is indicated.

Animals↗