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N H Axelsen

Publications and source records attributed to N H Axelsen.

At least 37 records · Page 2Linked to original sources
PubMed1981

Antigenic analysis of Treponema pallidum: cross-reactions between individual antigens of T. pallidum and T. Reiter.

Seven antigens were demonstrated in the Nichols pathogenic strain of Treponema pallidum when tested by cross immunoelectrophoresis against rabbit antibodies raised by immunization with T. pallidum sonicate. Indirect evidence was obtained for the presence of two more T. pallidum antigens. Of the nine antigens six reacted with antibodies in a human syphilitic serum pool. Cross-reactions between individual T. Reiter antigens and the seven directly demonstrated T. pallidum antigens were studied by different immunoelectrophoretic techniques, using rabbit anti-T. Reiter Ig, rabbit anti-T. pallidum Ig, and human syphilitic serum pool. Of the seven T. pallidum antigens three were found in T. Reiter, three had epitopes identical to corresponding antigens in T. Reiter, and one had both cross-reacting and T. pallidum-specific epitopes. Human syphilitic serum had antibodies against two of the T. pallidum-specific antigens and against four T. pallidum antigens cross-reacting with antigens of T. Reiter.

Animals↗
PubMed1981

Isolation of a heat-stable antigen from Treponema Reiter, using an immunoadsorbent with antibodies from syphilitic patients.

It was attempted to isolate antigens from Treponema Reiter, relevant to syphilis serology, by immunoadsorption with patients' antibodies coupled to CNBr--Sepharose 4B. One antigen was desorbed by 2 M KSCN in 0.05 M Tris--barbital buffer, pH 8.6. The recovery was 3% and 7% in two experiments. A small amount of human antibodies in the isolate was removed on an immunoadsorbent column with insolubilized rabbit antibodies against normal human serum proteins. The antigen thus obtained was immunologically pure when analysed by crossed immunoelectrophoresis. By electron microscopy of immunoprecipitates and by tandem crossed immunoelectrophoresis it was shown that the antigen differed from the flagellar antigen of T. Reiter, but was identical to antigen d previously described in T. Reiter. Antigen d could also be isolated from supernatants of T. Reiter cultures. The d antigen was not denatured at pH 2.8, by 8 M urea or by 3 M KSCN, and it resisted heating to 100 degrees C for 30 min. No protein could be detected in a concentrated preparation, and the antigen might be a polysaccharide. Antigen d is probably present in the sorbent used in the fluorescence treponemal antibody absorption (FTA-ABS) test and may constitute the active substance of this reagent.

Animals↗
PubMed1981

Isolation and characterization of TR-c, an antigen of the Reiter treponeme precipitating with antibodies in syphilis.

TR-c is a Reiter treponemal antigen that cross-reacts with an antigen in Treponema pallidum (Nichols pathogenic strain). Sera from patients with secondary syphilis contain precipitating antibodies against TR-c. The isolation of TR-c from a crude bacterial sonicate involves five fractionation steps: anion exchange chromatography (DE-52 Whatman), gel filtration (Ac-A-22, Ultrogel), and affinity chromatography respectively on phenyl-Sepharose CL 4B, iminodiacetic acid-Sepharose CL 4B, and lysine-Sepharose 4B. The purified TR-c was enriched 320 times compared with the starting material, and the recovery was 22%. TR-c was shown to be a protein, it did not bind to a series of lectins, and by gel filtration and polyacrylamide gel electrophoresis (PAGE) and mol. wt was determined to be in the range of 630,000-730,000. It was found by SDS-PAGE to be composed of identical subunits, each having a mol. wt of 48,000. The isolated TR-c was immunochemically pure when tested in crossed immunoelectrophoresis against polyspecific anti-Reiter Ig. The purified TR-c antigen was used for production of a monospecific rabbit antiserum. Monospecific rabbit anti-TR-c gave strong fluorescence with both the Reiter treponeme and T. pallidum.

Antibodies, Bacterial↗
PubMed1981

General paralysis of the insane associated with HLA-Aw32.

HLA-A, -B, and -C locus antigens were determined in 35 unrelated patients with general paralysis of the insane (GPI), and in 13 neurosyphilis patients without dementia. HLA-Aw32 was found more frequently (corrected p = 4.9 x 10(-2) in the GPI patients than in 1009 controls. None of the patients having neurosyphilis without dementia had HLA-Aw32. These findings indicate that genetically determined mechanisms may play a role in development of GPI. Further studies of such rare patients should be initiated to investigate whether these observations reflects a true association or whether they are due to chance. If possible other well defined groups of tertiary syphilis should also be studied.

Adult↗
PubMed1981

A simple method for the isolation of flagella from Treponema Reiter.

Flagella from Treponema Reiter were purified from a sonicate of the bacteria by diethylaminoethyl-cellulose chromatography followed by gel filtration on Sepharose CL-2B. The yield (0.8 mg flagellar protein per 8 g wet weight of treponemes) was identical to that obtained by previously described more time consuming methods. Crossed immunoelectrophoresis of the chromatographically isolated flagella against rabbit anti-T. Reiter immunoglobulin, monospecific anti-T. Reiter flagellar antibodies or human syphilitic serum in the upper gel showed two parallel but closely apposed precipitates. No contaminating material was found by electron microscopy of suspensions of flagella isolated by the new method. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of dissociated flagella showed three major and one minor band. It is concluded that the new method is quantitatively and qualitatively equal to earlier described purification procedures, but simpler to use.

Antigens, Bacterial↗
PubMed1980

Antibodies in secondary syphilis against five of forty Reiter treponeme antigens.

More than forty water-soluble antigens were found in the Reiter treponeme by crossed immunoelectrophoresis, using isolated and concentrated Ig from immunized rabbits. Five antigens reacted with antibodies in sera from selected patients with secondary syphilis, all having strong reactions in traditional tests for syphilis. No antibodies were found in selected healthy controls nonreactive in traditional syphilis tests. The five antigens represent available and potentially valuable antigens for development of new diagnostic syphilis tests. One of the antigens probably represents the axial filament. The findings open new possibilities for precise immunochemical studies of treponemes and of the immunology of syphilis.

Antibodies, Bacterial↗
PubMed1980

The antigens of Mycobacterium bovis, strain BCG, studied by crossed immunoelectrophoresis: a reference system.

A reference system for the soluble antigens of Mycobacterium bovis, strain BCG is described. The system is based on crossed immunoelectrophoresis with intermediate gel. A commercially available immunoglobulin preparation made from rabbit anti-BCG hyperimmune serum was used as reference antibodies, while a concentrated BCG culture filtrate was used as reference antigen. The pattern obtained was highly reproducible, and most of the components were stable when the fiftyfold-concentrated culture filtrate was stored at -20 degrees C. About thirty different antigenic components were selected as reference antigens and numbered. The majority of the reference antigens were present in extracts prepared from BCG by ultrasonication or bacterial press extraction. Use of the system for studies of antigenic relationship between mycobacteria, identification and quantification of antigens, and characterization of antimycobacterial antibodies are illustrated by examples. The antigens of two preparations of tuberculin purified protein derivative (PPD) were identified. The antigen designated BCG60 was found to be a najor constituent of tuberculin PPD. Evidence is presented that this antigen is cell wall associated.

Absorption↗
PubMed1980

Antigens and antibodies in Plasmodium falciparum malaria studied by immunoelectrophoretic methods.

Soluble plasma antigens in 53 Liberian patients with P. falciparum malaria were analyzed in double diffusion using plasma from 27 immune adults. One immune plasma reacted with 17% of the plasma samples and was used in subsequent quantitative immunoelectrophoretic (IE) studies as antiserum. By fused rocket IE 2 antigens were found in samples with parasitaemia (P) above 0.6% and above 4.5% P the antigens had grossly increasing concentration. In 22 samples of 0.6% P or more, 7 antigens were demonstrated by crossed IE. Two electrophoretically heterogeneous antigens. Ag-1 and Ag-2, were found most frequently. Ag-1 was partly heat-stable and was in some samples amphiphilic as shown by charge shift crossed IE. Ag-1 and Ag-2 did not contain integral erythrocyte membrane proteins, and Ag-1 is suggested to be a structural protein of P. falciparum. Twenty-six immune plasma samples were screened for antibodies against 4 antigens in crossed IE with intermediate gel. It is suggested that an index for protective immunity may be obtained by summation of semiquantitative titers obtained by crossed IE with intermediate gel using an antigen pool representing e.g. 20--30 soluble antigens.

Animals↗
PubMed1979

Detection of M-components by an easy immunofixation procedure: comparison with agarose gel electrophoresis and classical immunoelectrophoresis.

Commercial anti-gamma-alpha-mu and anti-kappa-lambda (mixture of commercial anti-kappa and anti-lambda) were used for immunofixation after agarose gel electrophoresis of 100 serum samples diluted 1 : 5. This simple screening method detected M-components in 39 sera. M-components were detected in 33 sera by agarose gel electrophoresis, and in 30 sera by classical immunoelectrophoresis. More than one band was detected in 15 sera by the screening method, in 3 sera by agarose gel electrophoresis, and in 2 sera by immunoelectrophoresis. The screening method was superior to the combined use of agarose gel electrophoresis and classical immunoelectrophoresis for detection of M-components, and easier to perform and interpret.

Animals↗
PubMed1979

Cross-reactions between mycobacteria. II. Crossed immunoelectrophoretic analysis of soluble antigens of BCG and comparison with other mycobacteria.

Cross-reactions between Mycobacterium bovis BCG and various other mycobacteria, Nocardia asteroides, Corynebacterium pyogenes and Listeria monocytogenes were studied by incorporating antibodies against these bacteria in the intermediate gel of a crossed immunoelectrophoretic system with BCG antigen and anti-BCG antibodies. In the BCG reference system forty-four distinct antigenic components were recorded, of which thiryt-three cross-reacted with Mycobacterium tuberculosis, twenty-five with M. avium, twenty-one with M. suvalii, eighteen with M. smegmatis, Fifteen with M. nonchromogenicum, twelve with M. phlei, eight with N. anteroides and two with C. pyogenes, whereas no cross-reaction was detected with L. monocytogenes. The value of the method for characterization of mycobacterial antigens is discussed. A taxonomic system based on this method appears particularly valuable for studies of non-cultivativable mycobacteria such as M. leprae. A majority of twenty-one patients with lepromatous leprosy had anti-BCG antibodies of restricted specificity, affecting only four or five BCG antigens, although one patient had twelve anti-BCG specificities. Most of these antibodies reacted with those BCG antigens that cross-react extensively with other mycobacteria.

Antibodies, Bacterial↗
PubMed1978

Demonstration of chymosin (EC 3.4.23.4) in the stomach of newborn pig.

The stomach of newborn pig contains a proteinase that is immunologically closely related to calf chymosin (rennin) (EC 3.4.23.4.). None of the pepsins from the stomach of adult pig is present in the newborn pig. Pig chymosin has optimal general proteolytic activity around pH 3.5. The ratio of milk-clotting activity to general proteolytic activity is about 30--70 times higher than that of pyloric and fundic pepsins.

Animals↗
PubMed1978

Mycobacterium leprae specific antibodies detected by radioimmunoassay.

A radioimmunoassay was developed for demonstration of antibodies against M. leprae specific antigenic determinants. The specificity of the assay was tested with hyperimmune rabbit antisera against other mycobacteria and shown to be very high. The titre of M. leprae specific antibodies in a lepromatous serum pool was 10(5). Sixty-one of sixty-two lepromatous sera, all of twelve borderline sera and twenty of forty-eight tuberculoid sera were positive in the assay, whereas all of thirty-eight control sera from tuberculin positive individuals from a leprosy non-endemic area were negative. Aplication as a diagnostic test for subclinical infection with M. leprae is discussed. The principle of the test appears promising for serological distinction between pulmonary infection with M. tuberculosis and other mycobacteria.

Antibodies, Bacterial↗
PubMed1977

Antigens in human glioblastomas and meningiomas: Search for tumour and onco-foetal antigens. Estimation of S-100 and GFA protein.

Extracts of glioblastomas and meningiomas were analysed by quantitative immunoelectrophoresis for the presence of foetal brain antigens and tumour-associated antigens, and levels of 2 normal brain-specific proteins were also determined. The following antibodies were used: monospecific anti-S-100 (glia specific); monospecific anti-GFA (glial fibrillary acidic protein), (astroglia specific); polyspecific anti-foetal brain (12-16th week of gestation); a polyspecific anti-glioblastoma antiserum, absorbed with insolubilized serum, haemolysate and normal brain extract; polyspecific anti-alpha-foetoprotein; and monospecific anti-ferritin. Using the antibodies raised against the tumours, several antigens not present in foetal or adult normal brain were found in the glioblastomas and the meningiomas. These antigens cross-reacted with antigens present in normal liver and were therefore not tumour-associated. S-100 was found in glioblastomas in approximately one tenth the amount in whole brain homogenate, whereas GFA was found 2-4 times enriched. The 2 proteins were absent in meningiomas. The possible use of the GFA protein as a marker for astroglial neoplasia is discussed. Five foetal antigens were found in foetal brain, but none in the tumours. alpha-Foetoprotein could only be demonstrated in foetal tissue extracts, including foetal brain, but not in tumours. Ferritin was detected in all tumour extracts, although the amounts determined were unrelated to histological tumour type.

Antigens, Neoplasm↗
PubMed1977

Antibody response in rabbits to immunization with Mycobacterium leprae.

Mycobacterium leprae purified from liver tissue of an infected armadillo (the A/10 preparation) was tested for antigenic composition by immunization of rabbits and characterization of the antibody response by crossed immunoelectrophoresis. The rabbit antisera detected seven distinct components in the M. leprae preparation. This number is far lower than in similar experiments with other mycobacteria. The M. leprae sonic extract gave far fewer lines after polyacrylamide gel electrophoresis and staining with Coomassie brillant blue than sonic extracts prepared from BCG, M. smegmatis, and M. phlei adjusted to the same protein concentration based on the Folin assay. The seven components detected in M. leprae cross-reacted extensively with M. avium, BCG, M. lepraemurium, M. smegmatis, and Nocardia asteroides. The seven components are involved in immune reactions in leprosy; antibodies against all of them were demonstrated in sera from patients with lepromatous leprosy, but the specificity of the antibodies varied from patient to patient. The reason for the demonstration of so few antigenic components and some of the implications of these findings for the use of armadillo-grown M. leprae to develop specific skin test reagents and in other aspects of leprosy research are discussed.

Animals↗
PubMed1976

Alpha-fetoprotein-like activity in sera from patients with malignant and non-malignant disease and healthy individuals.

A new method, radio-crossed immunoelectrophoresis, demonstrates alpha-fetoprotein (AFP) in sera with a sensitivity of 1 mug/1. By this method AFP with alpha mobility was not found in sera from healthy individuals, patients with chronic active hepatitis and cirrhosis, primary biliary cirrhosis, secondary liver cancer and cystic fibrosis. In some of the sera, AFP was elevated when measured by conventional radioimmunoassay method and the sera contained an AFP-like substance with gamma mobility when analyzed by radio-crossed immunoelectrophoresis. The nature of this gamma substance is still obscure and needs further investigation.

Cystic Fibrosis↗
PubMed1976

Immunochemical, chromatographic, and milk-clotting activity measurements for quantification of milk-clotting enzymes in bovine rennets.

Monospecific rabbit antibodies were produced against bovine chymosin (rennin) and bovine pepsin A and used for quantitative measurements of these enzymes by rocket immunoelectrophoresis. Bovine pepsin B was identified and measured quantitatively in tandem crossed immunoelectrophoresis, using a polyspecific antibody preparation. Chromatographically purified chymosin B and bovine pepsins A and B were used as standards. The contents of chymosin and bovine pepsin A were also determined by 2 forms of DEAE chromatography, and by an assay utilizing the ratio of milk-clotting activity at pH 6-0 and 6-5. Results obtained by measurements on 3 bovine rennets (calf rennet, adult bovine rennet, and a mixture of such types) by the different methods of analysis were in good agreement. The advantages of the immunochemical methods are direct and simultaneous identification and quantitation of enzymes.

Age Factors↗