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Immunological and morphological analysis of sodium dodecyl sulfate extract of Leptospira.

Sodium dodecyl sulfate (SDS) extract of Leptospira interrogans serotype icterohaemorrhagiae strain Shibaura was fractionated by rate zonal centrifugation in sucrose density gradient, and the fractions were analysed immunologically and morphologically. Two main peaks of antigenic activities were obtained. The first peak showed activities of strong indirect hemagglutination (IHA), weak complement fixation (CF), and low production of agglutinin in mice, and produced 5 precipitin lines in immunodiffusion with homologous strain antiserum. It gave only partial protection to guinea pigs. No recognizable structural components were found electron microscopically in the first peak. The second peak, on the other hand, showed no IHA activity, strong CF activity, high production of agglutinin in mice, and produced no precipitin line in immunodiffusion. It gave complete protection to guinea pigs. Membrane fragments of the enveloping sheath were found electron microscopically in the second peak. The protective activity of SDS extract of leptospira was thus intimately associated with the activityes of agglutinin production and CF, as well as with the membranous structures of the enveloping sheath.

Antigen-Antibody Reactions↗

Immunological relations of proteins from four salmonellae sharing an "O" factor 8.

The proteins from S. virginia, with the sole 8 "O" factor, precipitated against homologous and related heterologous sera by a conspicuous, homogenous line of serological identity, with proteins from: S. newport (6.8), S. blockley (6.8), S. emek (8.20). The proteins, however, were not involved in the bacterial agglutinations since the absorptions, which removed the common precipitins from the sera, did not modify the homologous agglutinations. The results with anti-S. newport and anti-S. blockley sera sharing identical "O" factors while displaying different immunochemical compositions as well as the strong immunochemical relations found between S. virginia and S. newport belonging to the different subgroups C2 and C3 underline the non-relatedness of agglutinins and precipitins.

Agglutination Tests↗

Isolation and characterization of porcine parathyroid cathepsin B.

Cathepsin B was isolated from porcine parathyroid tissue and from liver by a procedure involving acetone precipitation, gel filtration, and carboxymethylcellulose chromatography. The final preparations of each migrated as single bands upon sodium dodecyl sulfate polyacrylamide gels but exhibited several minor active variants upon isoelectric focusing. The parathyroid and liver enzymes were similar to each other and also resembled cathepsin B from other sources. The molecular weights for the porcine enzymes were estimated as 25,000, and the isoelectric point was at pH 4.8. The parathyroid enzyme cleaved benzyloxycarbonyl-Val-Lys-Lys-Arg-(4-methoxy)-2-naphthylamide at pH 5.8 and 37 degrees C with a Km of 0.14 mM and a kcat of 68 s-1. The pH optimum for this reaction was pH 6 to 7. The enzyme was unstable above pH 7.5 and below pH 4.5. It was strongly inhibited by HgCl2, ZnSO4, iodoacetate, iodoacetamide, and N-ethylmaleimide which indicated that it is a thiol protease, and by leupeptin, a strong inhibitor of cathepsin B from other sources. Antibodies to the parathyroid enzyme were elicited in rabbits. The antisera formed single precipitin bands upon double diffusion in agar gels against both the parathyroid and liver enzymes. Precipitin bands were formed at both pH 6 and pH 8.5 which indicated that the antisera recognized both native and denatured forms of the enzymes.

Amino Acids↗

Molecular heterogeneity of Hageman trait (factor XII deficiency): evidence that two of 49 subjects are cross-reacting material positive (CRM+).

We have studied plasmas of 49 individuals with homozygous Hageman trait from 42 kindreds, all of which contained less than 1% of the Hageman factor (factor XII) clotting activity of pooled normal plasmas. Forty-seven plasmas contained less than 1% of Hageman factor antigen. In two other, unrelated individuals with Hageman trait, nonfunctional material immunologically indistinguishable from normal Hageman factor was detected in plasma by radioimmunoassay at concentrations of 39% and 80%, respectively. These plasmas did not contain circulating anticoagulants against Hageman factor and, as in ordinary Hageman trait, displayed impaired surface-mediated plasma reactions such as fibrinolysis and kinin generation. Upon immunodiffusion against anti-Hageman factor serum, these plasmas formed a single precipitin line of complete identity with normal plasma or purified Hageman factor. Upon immunoelectrophoresis, the precipitin line had the same mobility as normal Hageman factor. Nonfunctional Hageman factor and normal Hageman factor behaved identically on a Sephadex G-150 column (apparent MW = 100,000) and on sucrose density-gradient centrifugation (4.5S). Nonfunctional Hageman factor was adsorbed to kaolin as readily as normal Hageman factor, suggesting that the binding site to negatively charged surfaces is different from functional sites. Antiserum raised against Hageman factor-like material in a CRM+ Hageman trait plasma specifically inactivated Hageman factor activity in normal plasma. The plasmas of three heterozygotes in these families contained approximately twice as much Hageman factor antigen as Hageman factor activity, whereas those of 16 heterozygotes in ordinary (CRM-) Hageman trait families contained approximately equal amounts of activity and antigen. The present study indicates that rarely homozygous Hageman trait may be CRM+ and that this defect is genetically determined.

Cross Reactions↗

Use of radioimmunoassays to determine the concentration of streptococcal group-specific antibodies in rabbit antisera.

A radioimmunoassay was developed for the quantitation of antibodies to the Group A, A-variant, and C carbohydrates in rabbit streptococcal antisera. The assay employs radiolabeled purified Group carbohydrate which has been tyrosylated to allow for incorporation of 125-I. This assay has an advantage over the intitative precipitin test because it measures non-precipitating antibody in addition to precipitating antibody. Furthermore, 7S anti-IgG in rabbit antisera give a falsely elevated value for the antibody concentration in the quantitative precipitin test. This did not occur with the radioimmunoassay. The assay described is reproducible, sensitive, and uses little antisera.

Adsorption↗

Antibody responses of turkeys experimentally exposed to Mycoplasma synoviae.

The antibody response of turkeys exposed to Mycoplasma synoviae intravenously and by way of air sacs was determined by tube agglutination, plate agglutination, hemagglutination-inhibition (HI), and gel diffusion precipitin tests. The results suggested that continued antigenic stimulation was lacking in most turkeys and that the response was due mostly to IgM-type immunoglobulin. Under those conditions, both types of agglutination tests were effective and were more sensitive indicators of exposure than the HI test. The gel diffusion precipitin test was not considered effective under the conditions of this study. HI activity occurred in serums of intravenously exposed turkeys within 4 days of exposure. The sensitivity of this activity to 2-mercaptoethanol treatment suggested that IgM was responsible.

Animals↗

Autoantibodies in serum and sputum from patients with cystic fibrosis.

Sera from 89 patients with cystic fibrosis (CF) and 88 control persons were examined for the occurrence of rheumatoid factors (RF) of the IgG, IgA and IgM classes by an indirect immunofluorescence method and by the latex fixation slide test. The prevalence of RF-IgG was significantly higher (88%) (p less than 0.0005) among the CF patients than among the control persons (7%), while no difference was found between the two groups with regard to RF of the IgA or IgM classes. Fifty-five of the CF patients had chronic Pseudomonas aeruginosa infection in their lungs and two or more precipitins against these bacteria in their sera determined by crossed immunoelectrophoresis. These CF patients did not differ from the 34 CF patients without chronic P. aeruginosa infection, neither with regard to prevalence nor titer of RFs, but there was a positive correlation between the number of P. aeruginosa precipitins in the 55 chronically infected CF patients and their titers of IgG-RF. Nineteen CF patients were examined also for RFs, antinuclear antibodies (ANA) and anti-DNA antibodies in their sputum sol phase and corresponding sera. RFs were demonstrated in the sputum sol phase from 6 of the patients by the latex fixation test, whereas their sera were negative in this test, possibly indicating a local production of RF. Positive reactions for ANA and anti-DNA antibodies were found in 7 and 10 of the sputa respectively, and in higher titers than in the corresponding sera, also suggesting a local production. Titers of autoantibodies in sputum were low and no difference was found between patients with chronic P. aeruginosa infection and patients without P. aeruginosa infection. The possible role of autoantibodies in the patogenesis of pulmonary tissue damage in CF patients is discussed.

Adolescent↗

Role of Aspergillus and Candida species in allergic bronchopulmonary mycoses. A comparative study.

Allergic bronchopulmonary aspergillosis (ABPA) and allergic bronchopulmonary candidiasis (ABPC) has been diagnosed in 20 and 13 cases respectively with one case in common, on the basis of laboratory and clinical findings. Most of the ABPA cases (60%) diagnosed had an early onset of respiratory symptoms, i.e. below the age of 30 years, while most of ABPC cases (69%) had a late onset of respiratory symptoms, i.e. after the age of 30 years. The precipitin bands in ABPA and ABPC were R-type and H-type, respectively. Apparently, ABPA and ABPC are independent of one another in origin as suggested by specific precipitins and dual skin reaction. In ABPA, A. fumigatus appears to be the primary causal organism although the contributory role of other species of Aspergillus, which include A. flavus, A. nidulans, A. terreus and A. niger, is evident from the present study. It is concluded that allergic bronchopulmonary mycoses (ABPM) could be caused by several fungal species independently or jointly belonging to the genera Asperigillus and Candida.

Antigens, Fungal↗

Demonstration of avian influenza-A virus in Iran by immunodiffusion technique.

A total of 1000 chicken serum samples (CSS) and 235 turkey serum samples (TSS) were tested by an immunodiffusion procedure against soluble antigen (S-antigen) prepared from avian influenza-A virus (AIAV), T/Calif/5142/66. None of the CSS tested developed any precipitin line, whereas 8.9% of the TSS tested developed well-defined precipitin lines against S-antigen. This observation confirmed the presence of AIAV in Iran.

Animals↗

Sodium-potassium-activated adenosine triphosphatase of electrophorus electric organ. X. Immunochemical properties of the Lubrol-solubilized enzume and its constituent polypeptides.

Detergent (Lubrol WX)-solubilized sodium-potassium-activated adenosine triphosphatase ((Na+ + K+)-ATPase) of electrophorus electric organ contains two major constituent polypeptides with molecular weights of 96,000 and 58,000 which can be readily demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. These two polypeptides can be clearly separated and can be obtained in milligram quantities by preparative sodium dodecyl sulfate gel electrophoresis. The separated polypeptides, after removal of sodium dodecyl sulfate, and Lubrol-solubilized (Na+ + K+)-ATPase activity to some degree. Moreover, the degree of inhibition is directly proportional to the increasing amounts of antisera. The inhibition is maximal 4 weeks after the first injection. Immunodiffusion in 1% agar gel indicated that only Lubrol-solubilized enzyme antiserum, but not 58,000-dalton or 96,00-dalton polypeptide antiserum, gives one major precipitin band. However, specific complex formation between each polypeptide antiserum and Lubrol-solubilized enzyme occurs. This was demonstrated indirectly. After incubating Lubrol-solubilized enzyme with increasing amounts of polypeptide antisera at 37 degrees for 15 min, they were placed in the side wells of an immunodiffusion plate with antiserum against Lubrol-solubilized enzyme in the central well. The intensity of the precipitin band decreased with increasing amounts of polypeptide antisera. Thus, the results indicate that both 96,000-dalton and 58,000-dalton polypeptides are integral subunits of (Na+ + K+)-ATPase.

Adenosine Triphosphatases↗

Immunochemical studies with synthetic immunogens chemically related to peptidoglycan.

Rabbits were immunized with synthetic immunogens HSA-(Gly-L-Ala-L-Ala-D-Ala-D-Ala)39 and HSA-(Gly-gamma-D-Glu-L-Ala-D-Ala-D-Ala)40, respectively. Antibodies against HSA-(Gly-L-Ala-L-Ala-D-Ala-D-Ala)39 showed a strong precipitin reaction with the homologous antigen, with HSA-(Gly-gamma-D-Glu-L-Ala-D-Ala-D-Ala)40 and with solubilized peptidoglycan containing peptide subunits with C-terminal D-alanyl-D-alanine. The albumin-peptide conjugates also cross-reacted with rabbit antisera to Streptococcus A-variant, which contain antibodies directed against the peptide moiety of peptidoglycan. The proof for identical determinant groups of peptidoglycan of Streptococcus A-variant and HSA-(Gly-L-Ala-L-Ala-D-Ala-D-Ala)39 was furnished by Ouchterlony gel diffusion studies and by the appropriate inhibition tests of the quantitative precipitin reaction. Immunization of rabbits with HSA-(Gly-gamma-D-Glu-L-Ala-D-Ala-D-Ala)40 yielded antisera which, besides the specificity of antisera to HSA-(Gly-L-Ala-L-Ala-D-Ala-D-Ala)39, showed an additional specificity.

Amino Acids↗

[Evaluation of the results of ELISA in the quantitative determination of antibodies against infectious bursitis in poultry].

Specific antibodies were investigated in serums of chicks vaccinated with live vaccine and revaccinated with inactivated vaccine against the infectious bursal disease virus, using three methods. An ELISA technique was used to determine antibody titres at a fourfold serum dilution; the reaction was evaluated visually. The results were compared with the titres of neutralizing antibodies and percentage of samples with precipitin activity (Fig. 1). The average values of neutralizing antibody titres and ELISA titres were found to have an analogical pattern; a decrease in maternal antibodies on the first days of chick life and an increase in the antibodies after vaccination, accompanied by an increase in precipitin activity, were typical in these tests. Using the different ELISA technique, 138 samples of fowl serum were examined (Fig. 2). The high correlation, r = 0.85, was found between the ELISA titres determined by visual reading of the reaction within the fourfold serum dilutions and the absorbance values determined at single serum dilution. Applying a spectrophotometer programme, a scale of antibody quantification was made up pursuant to the intensity of immunoenzymatic reaction. For the purposes of method reproducibility, the evaluation was made within the average values of absorbance of positive serum on the one hand and of negative serum on the other. The span of these values was divided into ten equal parts, designated by degrees 0 to 9. Corresponding degrees of positivity were assigned to the examined samples in dependence on the determined value of absorbance (Fig. 3). The correlation r = 0.61 was found between the ELISA values and the titres of neutralizing antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Screening for antibodies against Aleutian disease virus (ADV) in mink. Elucidation of dubious results by additive counterimmunoelectrophoresis.

In order to distinguish true positive results in counterimmunoelectrophoresis from false positive ones an additive counterimmunoelectrophoresis was developed. The method was tested on selected mink serum samples as part of a routine testing for antibodies towards Aleutian disease virus on 3 million blood samples. The procedure of the method is, that a known positive serum sample is mixed with the patient serum to be tested. The result from a false positive sample will be one precipitin line towards virus and one nonspecific line. If the serum sample is a true positive one, the antibodies originating from the patient serum will be added to the antibodies in the standard positive serum giving only one precipitin line. The system is further extended by testing the serum samples towards an antigen preparation containing all the cellular components but free from virus.

Aleutian Mink Disease↗

Identification of blood meals of blood-sucking arthropods.

The identification of blood meals of blood-sucking arthropods requires a test which is sensitive enough to detect even partially digested blood and specific enough to identify the various hosts. The technique of preference is the precipitin test which makes use of the specific combination of the serum proteins of the blood. The preparation of the blood meal extract and the procedure for the absorption of the antisera is described and various methods of performing the precipitin test are mentioned. When the hosts involved are closely related to each other it is necessary to use the inhibition test. The blood meal will specifically inhibit, under specified conditions, the agglutination of tanned and sensitized red blood cells which is caused by a suitable antiserum. The procedure adopted for the identification of blood meals derived from a large variety of hosts is described in detail.

Animals↗

Farmer's lung disease in north-western India--a preliminary report.

A study of farmer's lung (FL) disease was carried out in 197 subjects engaged in farming and having respiratory complaints of varying duration. It revealed that 13.2% of the subjects had precipitating antibodies against thermophilic actinomycetes, with Faenia rectivirgula (Micropolyspora faeni) alone accounting for 85% of the positive reactions. Precipitating antibodies against Thermoactinomyces vulgaris and T. thalpophilus were observed only in 1.5% and 0.5% of the subjects, respectively. Two subjects concomitantly demonstrated F. rectivirgula and T. vulgaris-specific serum precipitins. Sixty (30%) of the subjects related their respiratory symptoms to exposure to wheat straw/thresher's dust or other vegetable substrata in the working environment. Based upon a suggestive clinical history, roentgenography, pulmonary function studies and demonstration of serum precipitins against F. rectivirgula, FL was diagnosed in 4 subjects whose salient features are presented and discussed. To the best of our knowledge, this is the first authentic report on FL from India. A comprehensive epidemiological survey is indicated to determine the prevalence of FL in different geo-climatic regions of the country.

Adult↗

Defining the carbohydrate specificities of Abrus precatorius agglutinin as T (Gal beta 1----3GalNAc) greater than I/II (Gal beta 1----3/4GlcNAc).

The combining site of the nontoxic carbohydrate binding protein (Abrus precatorius agglutinin, APA) purified from the needs of Abrus precatorius (Jequirity bean), was studied by quantitative precipitin and precipitin-inhibition assays. Of 26 glycoproteins and polysaccharides tested, all, except sialic acid-containing glycoproteins and desialized ovine salivary glycoproteins, reacted strongly with the lectin, and precipitated over 70% of the lectin added, indicating that APA has a broad range of affinity and recognizes (internal) Gal beta 1----sequences of carbohydrate chains. The strong reaction with desialized porcine and rat salivary glycoproteins as well as pneumococcus type XIV polysaccharide suggests that APA has affinity for one or more of the following carbohydrate sequences: Thomsen-Friedenreich (T, Gal beta 1----3GalNAc), blood group precursor type I and/or type II (Gal beta 1----3/4GlcNAc) disaccharide determinants of complex carbohydrates. Among the oligosaccharides tested, the T structure was the best inhibitor; it was 2.4 and 3.2 times more active than type II and type I sequences, respectively. The blood group I Ma-active trisaccharide, Gal beta 1----4GlcNAc beta 1----6Gal, was about as active as the corresponding disaccharide (II). From the above results, we conclude that the size of the combining site of the A. precatorius agglutinin is probably as large as a disaccharide and most strongly complementary to the Gal beta 1----3GalNAc (T determinant) sequence. The carbohydrate specificities of this lectin will be further investigated once the related oligosaccharide structures become available.

Binding, Competitive↗

Health effects of inhalation exposure to organic dust in hops farmers.

Medical examinations were performed in a group of 23 hops farmers exposed to organic dust from hop (Humulus lupulus). The examinations took place in individual farms during harvesting, sorting and transporting of hop cones. As a reference group, 50 urban dwellers not exposed to organic dust were examined. There were conducted physical examinations, interviews concerning the occurrence of respiratory disorders and work-related symptoms, lung function tests, determination of cytokines concentrations, and allergological tests comprising skin prick test with 4 microbial antigens associated with organic dust, precipitin test with 12 microbial antigens, and a test for inhibition of leukocyte migration. Five farmers (21.7%) reported occurrence of work-related symptoms, including dry cough and dyspnoea. Eight farmers (34.8%) reported symptoms of chronic bronchitis. Mean spirometric values were within normal ranges. The farmers showed positive responses in precipitin test and test for inhibition of leukocyte migration to antigens of environmental microbes, mainly to the antigen of Gram-negative bacterium Pantoea agglomerans. The results showed a potential risk of occupational respiratory diseases in the population of hops farmers.

Adult↗

Biological and molecular characterization of lettuce mosaic virus from Tehran province in Iran.

In this study, lettuce samples having LMV infection symptoms were collected from Tehran fields during 2003. Samples tested for LMV infection by immuno printing. Three positive samples in immuno printing collected and their characteristics were determined. In mechanical inoculation, these Isolates produced symptoms on Chenopodium quinoa, C. amaranticolor, Gomphrena globosa, Nicotiana benthamiana, Lactuca sativa cv. Mantilia and cv. Terocadero (which contains the mol1 resistance gene and susceptible respectively), but not cv. Salinas 88 (which contains the mol2 resistance gene). LMV was purified and LMV polyclonal antiserum was produced in rabbit by a series of intravenous and intramuscular injections, the precipitin titre of this antiserum was 1:1024. Gel double diffusion test (GDDT) was performed, and precipitin bands appeared. SDS-PAGE and western blotting showed the presence of coat protein 29 kDa. In IC-RT-PCR with on LMV specific primer pair, an approximately 1300 bp fragment was amplified.

Geography↗