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B Teisner

Publications and source records attributed to B Teisner.

At least 73 records · Page 4Linked to original sources
PubMed1986

Measurement of C3 conversion by ELISA estimation of neo-determinants on the C3d moiety.

An ELISA assay estimating neo-determinants on the C3d moiety is described. The C3d neo-determinants were detected by incubating the sample on F(ab')2 anti-C3d-coated plates followed by development with biotin-labelled anti-C3d and enzyme-labelled avidin. The assay was compared with rocket immunoelectrophoresis (IE) and crossed IE. Serum from a factor I deficient patient showed no detectable C3d when analysed by rocket IE, but activation was evident when analysing by crossed IE or ELISA. The results suggest that the neo-determinants detected by ELISA become exposed when C3 is split into C3a and C3b and this interpretation was supported by kinetic analysis of C3 activation by the three methods.

Complement Activation↗
PubMed1986

Immunohistochemical aspects of immunological cross-reaction and masking of epitopes for localization studies on pregnancy-associated plasma protein A.

The influence of antibody absorption procedures and proteolytic pre-treatment of formaldehyde-fixed placental tissue on the localization of pregnancy-associated plasma protein A by immunoperoxidase technique was examined. Apparently monospecific IgG fraction of the anti-plasma protein applied directly on fixed tissue resulted in staining of connective tissue and a thin apical rim of the syncytiotrophoblast. Further absorption of the antibody with foetal connective tissue abolished this staining reaction. Pre-treatment of the fixed placental tissue with trypsin prior to application of the antibody, which had been absorbed with connective tissue, resulted in staining within the cytoplasm of the syncytiotrophoblast exclusively. Identical staining was seen when this IgG preparation was used directly on frozen placental tissue. The results point to the importance of the specificity of the antibody preparations and of proteolytic unmasking of epitopes when fixed tissues are used for localization studies of pregnancy-associated plasma protein A by immunoperoxidase technique.

Epitopes↗
PubMed1986

A family with complement factor I deficiency.

A family with inherited factor I deficiency is described. The proband was a 19-year-old Caucasian female with one episode of meningococcal meningitis and one episode of suspected septicaemia of unknown cause. Two obligate and two probable heterozygotes with factor I levels below the lower limit of the reference range were identified. None of these exhibited increased susceptibility to infectious diseases. The inheritance was autosomal codominant. In addition, molecular heterogeneity of factor H in plasma from the proband but not from any other family members was demonstrated by crossed immunoelectrophoresis. The migration of factor H component of fast electrophoretic mobility was retarded by antibodies to C3c and C3d, suggesting the presence of a fluid-phase complex between factor H and excess C3b generated by the uncontrolled activity of the amplification loop.

Adult↗
PubMed1986

Comparison of different antibody preparations against pregnancy-associated plasma protein-A (PAPP-A) for use in localization and immunoassay studies.

Four antibody preparations against pregnancy-associated plasma protein (PAPP-A) were compared in order to find an explanation for the contradictory results published on tissue localization, clinical usefulness and biological function of PAPP-A. One of the preparations studied was a rabbit anti-PAPP-A antiserum which has been offered for general scientific use (Bischof et al. 1979). Only the IgG fraction of anti-PAPP-A antisera which appeared to be monospecific and had been further absorbed with fetal connective tissue gave specific uniform staining of the cytoplasm of the syncytiotrophoblast exclusively. Circulating PAPP-A could not be detected by RIA employing this IgG preparation in the non-pregnant state, or before 18 days after conception. Circulating PAPP-A could be detected in all seven pregnant women studied within 4 weeks after conception. Identical results were obtained with a commercially available IgG fraction against PAPP-A.

Animals↗
PubMed1986

Relationship between levels of rheumatoid factor isotypes and complement component C3 conversion in blood from patients with rheumatoid arthritis.

Conversion of complement component C3 in plasma from rheumatoid arthritis patients was measured by two different methods. One of the methods gives an estimation of C3 conversion by ELISA measurement of neodeterminants present on the C3d moiety; the other method measures C3 split products expressing D, but not C, epitopes by rocket immunoelectrophoresis (RIE) with intermediate anti-C3c gel. Results from 20 RA patients obtained by the two methods did not correlate significantly (R = 0.52, 0.02 less than p less than 0.05). The results were compared to the level of rheumatoid factors (RFs) of IgG, IgM, and IgA class in serum. A significant correlation was found between the concentration of C3d measured by RIE and level of IgG RFs, whereas neither IgM nor IgA RFs showed correlation to complement activation. The results of the ELISA estimation of C3 activation showed no correlation with the RF level.

Arthritis, Rheumatoid↗
PubMed1986

Quantitative comparison of circulating immune complexes in normal pregnancy and pregnancy related hypertension.

Using two different Clq-dependent assays for quantification of circulating immune complexes (CIC), the levels were compared in sera from 32 women with pregnancy-related hypertension and in sera of 32 matched controls. No difference in the CIC levels was observed. The levels of CIC in the hypertensive patients were not correlated to placental weight, fetal weight, or diastolic blood pressure.

Antigen-Antibody Complex↗
PubMed1986

Circadian and diurnal variation of circulating immune complexes, complement-mediated solubilization, and the complement split product C3d in rheumatoid arthritis.

Nine patients with active classical rheumatoid arthritis (ARA criteria) were studied with reference to circadian variation of immunological and clinical parameters. Complement-mediated solubilization (CMS) of immune complexes (IC) and the level of circulating IC were found to be inversely related with low CMS and increased IC levels in the morning, and vice versa in the afternoon. Bed rest and exercise did not influence these fluctuations. The C3d concentration in plasma was increased but showed no diurnal or circadian periodic fluctuations when the levels were corrected for fluctuations in plasma albumin concentration. Clinical assessment by means of pain score exhibited marked variations, with high scores in the morning, and lower in the daytime, whereas measurements of Ritchie's joint index showed no consistent pattern. The circadian variations in CMS, serum IC and clinical parameters indicate the need to collect blood specimens and perform clinical examinations of patients at a fixed time of day.

Adult↗
PubMed1985

The selection of antibodies with defined desorption properties from precipitated immune complexes for use in immunoadsorption procedures.

A general method for preparing immunosorbents with preselected antibody avidity is described. The method, which is a modification of a method described previously, also includes immunospecific purification of the ligand prior to coupling on the gel matrix. Polyclonal anti-alpha-1-fetoprotein antibodies in precipitated immune complexes were separated according to their avidity (low, intermediate and high) by dissociation with agents of increasing efficiency. After solid-phase coupling the antigen binding activity of the separated antibody preparations was examined according to recovery, capacity and binding strength. Antibodies of intermediate avidity derived from the immune complexes demonstrated optimal properties for preparative affinity chromatography.

Antibody Affinity↗
PubMed1985

Placental protein and hormone measurements in twin pregnancy.

Maternal serum levels of human placental lactogen (hPL), schwangerschaftsprotein 1 (SP1), pregnancy-associated plasma protein A (PAPP-A), placental protein 5 (PP5) and total oestriol (E3) were measured serially in 35 twin pregnancies during the third trimester. Eighteen pregnancies had major complications including dysmaturity of one or both fetuses in nine, premature labour in six, and placental abruption in three. Serum levels of all five variables were higher than in singletons, this distinction being greatest for hPL and lowest for SP1 and E3. The levels of hPL, PP5 and E3 just before delivery were significantly correlated with the total birthweight, a correlation with placental weight being evident only for hPL and PP5. A significant correlation between the five biochemical variables at 33-34 weeks was only seen between hPL and PAPP-A. Protein and hormone levels in the abnormal twin pregnancies were not apparently different from those in the normal twin pregnancies. These data suggest that only hPL levels biochemically reflect this extreme of fetal and placental growth, but that neither the levels of hPL nor any of the other biochemical indices examined are altered in abnormalities in twin pregnancy.

Birth Weight↗
PubMed1985

Does ultrasound examination render biochemical tests obsolete in the prediction of early pregnancy failure?

Serum levels of fetal, placental and maternal hormones and proteins [alpha-fetoprotein (AFP), human chorionic gonadotrophin, human placental lactogen, schwangerschaftsprotein 1, pregnancy associated plasma protein-A (PAPP-A), oestradiol-17 beta, progesterone, pregnancy zone protein] were measured in 108 women with bleeding during the first half of pregnancy. Ultrasound examination at the time of each blood sampling revealed a fetal heart action on at least one occasion in 77 women. Spontaneous abortion occurred in 42 pregnancies, 31 of these showed no ultrasound sign of fetal life, whilst the fetal heart action was observed repeatedly until abortion in the remaining 11 women. Abnormally low levels of PAPP-A were most likely to indicate pregnancy failure, in particular if the fetal heart action was seen at the time of blood sampling. The predictive value, sensitivity and relative risk of a single depressed PAPP-A level were respectively 49, 89 and 41%, the predictive value of a normal result being 99%. With the exception of AFP, all other biochemical indices examined were consistently in the normal range in this group of women. If ultrasound findings were not considered, the biochemical indices were of comparable value in the prediction of spontaneous abortion. PAPP-A levels were uniformly depressed in all patients who spontaneously aborted, frequently weeks before this event, in the presence of a live fetus.

Abortion, Threatened↗
PubMed1985

Humoral immunity to dietary antigens in healthy adults. Occurrence, isotype and IgG subclass distribution of serum antibodies to protein antigens.

The occurrence of antibodies to five dietary protein antigens in the sera from 21 healthy adults was investigated by a modified Farr assay. Antibody to ovalbumin (OA) occurred most frequently (90%) whereas only 24% had antibodies to alpha-lactalbumin (ALA). No correlation was noted between the titer of antibodies against bovine serum albumin (BSA) and OA in the single individual. The avidity constants (10(8)-10(9) l/mol) and cross-reactivities against other albumins of anti-BSA antibodies in two human sera were comparable to that of the antibodies in pooled hyperimmune rabbit antiserum. Crossed radioimmunoelectrophoresis showed serum anti-BSA and anti-OA antibodies to be predominantly of the IgG class (13/13, 10/10), occasionally of the IgA- (6/13, 1/10) and rarely of the IgM class (1/13, 0/10). Analysis by radioelectroimmunoassay (rocket immunoelectrophoresis) of the IgG subclass distribution of anti-BSA and anti-OA antibodies showed total absence of IgG3. In contrast, antibodies of the IgG4 subclass were frequently present even in sera with very low levels of total IgG4.

Adult↗
PubMed1985

Immunoelectrophoretic analysis of C4 split products expressing D but not C epitopes: influence of storage, Ca2+ and Ca2+-chelating agents.

Based on immunoelectrophoretic methods a heterogeneity in the electrophoretic mobility of C4d was observed. C4d was defined immunochemically as C4 molecules expressing D but lacking C epitopes. A beta-mobile form was observed when EDTA or heparin was not added to the sample prior to electrophoretic analysis. This component was generated during electrophoresis. Another C4d component migrating to the post-albumin region probably represented an in vivo generated split product. However, this C4d form was also produced during storage of serum or plasma at room temperature and its formation was enhanced in the presence of EDTA. Based on these findings standard conditions for collection and storage of clinical samples for quantification of C4d by electroimmunoassay are suggested.

Calcium↗
PubMed1985

Seminal plasma levels of PAPP-A in normospermic and oligospermic men and tissue localization of PAPP-A in the male genital tract.

Radioimmunoassay, gel filtration, isoelectric focusing, and immunoperoxidase methods were used to study the levels, properties, and localization of pregnancy-associated plasma protein A (PAPP-A) in the human seminal plasma and male genital tract. Seminal plasma specimens from 20 normospermic and 20 oligospermic men were studied. PAPP-A was found in 30 of 40 samples, the levels ranging from undetectable to 135 micrograms/liter (median 35 micrograms/liter) in the normospermic group and from undetectable to 111 micrograms/liter (median 21 micrograms/liter) in the oligospermic group. There was no significant difference in the PAPP-A levels between the two groups, and no correlation was observed between the seminal plasma PAPP-A levels and the volume of seminal plasma or the sperm count or the viability of spermatozoa. Serial dilutions of seminal plasma and PAPP-A standard yielded parallel dose-response curves, and incubation with seminal plasma did not result in any change in the elution pattern of [125I]PAPP-A in gel filtration. PAPP-A-immunoreactive material from seminal plasma eluted as two peaks, the major one corresponding to the elution volume of purified PAPP-A and the minor eluting more slowly. The isoelectric point of seminal plasma PAPP-A was 4.3-4.7 and that of term pregnancy serum was 4.2-4.6. In the immunoperoxidase staining, PAPP-A was seen in the epithelium of the prostate, seminal vesicle, and the ampullar part of the vas deferens but not in the testis, epididymis, proximal parts of vas deferens or urethra. The results confirm the occurrence of PAPP-A in the seminal plasma but do not suggest any clinical utility for seminal plasma PAPP-A measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗