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At least 19 recordsLinked to original sources
PubMed1990

Recent progress in mite allergen immunochemistry.

The successful purification of several mite allergens within the last few years has considerably enhanced our understanding of mite allergen immunochemistry. The role of these glycoproteins in stimulating human IgE ab and their role as immunogens in mice and rabbits has been studied extensively in a number of laboratories worldwide. In particular, purified allergens have facilitated the production of murine IgG Mabs that have been used to purify mite allergens by affinity chromatography; to investigate the diversity of antigenic sites on purified allergens; and to develop Mab based immunoassays for measuring allergen concentrations in dust samples and extracts. Full amino acid sequencing of several mite allergens is now in progress together with efforts to identify antigenically important peptide fragments. Such investigations are aimed to further increase our knowledge of humoral and cellular immune responses at the molecular level. For years, pollen counts have been used to judge airborne pollen allergen levels and to predict, in turn, the severity of symptom days for patients with hay fever. In contrast, simple methods for measuring dust allergens (e.g., mite allergen) have not been available. The development of Mab immunoassays, which can be converted from radiolabeled to enzyme labeled or fluorescence labeled assays, should provide rapid and quantitative measurements of specific mite allergen levels in house dust. Not only can such measurements provide useful clinical information in judging the exposure of patients to mite allergen, but the effectiveness of allergen avoidance regimes can be monitored objectively. By measuring the concentration of specific allergens in extracts, these assays could significantly improve efforts to standardize extracts used for diagnosis and treatment.

Allergens↗
PubMedDate not supplied

The immunochemistry of sandwich ELISAs--V. The capture antibody performance of polyclonal antibody-enriched fractions prepared by various methods.

Studies compare the performance of antibody-enriched serum fractions prepared by various methods, when adsorbed on polystyrene microtiter wells as capture antibodies (CAbs) and tested against multivalent antigens. The criteria of performance in the RIA used included antigen capture capacity (AgCC) and the nmol of functional capture sites per microtiter well (CAbt). Affinity purified polyclonal (pAb) and monoclonal antibodies (mAb) were employed as reference CAbs. AgCC was highest for enriched fractions prepared using caprylic acid and a high-pressure SpG affinity column. The performance of capture antibodies is expressed by an equation which was empirically derived and experimentally tested; CAbt x AgCC/ng adsorbed IgG. In terms of this parameter, CAb-enriched fractions prepared with caprylic acid performed best. The data reported also provide insight into solid-phase ligand immunochemistry. Adsorbed polyclonal CAb performed with remarkable homogeneity in percent bound and in Scatchard plots. Values obtained for CAbt from Steward-Petty plots were directly correlated with the length of the LBR of log-log percent bound plots but indicated that less than 10% of the potential capture sites of polyclonal CAbs remained functional after adsorption; mAb showed a more serious loss of activity. The loss of CAbt was a general phenomenon for all preparations tested although relative to their antibody content, certain antibody-enriched fractions retained a higher proportion of CAbt than their affinity-purified counterparts. Comparative studies in which the activity of adsorbed mAb and pAb was compared to the same antibodies immobilized by a non-adsorptive procedure, indicated that adsorbed CAbs also express lower affinity. The studies we report offer a single parameter criterium for comparatively evaluating CAb performance while simultaneously revealing the need to develop immobilization procedures that can preserve CAbt and antibody affinity so that immunoassays with wide dynamic ranges and high AgCC can be developed without waste of antibody.

Adsorption↗
PubMed1992

[Chemistry and immunochemistry analysis of the soluble antigens of newborn larvae of Trichinella spiralis].

The soluble antigens of newborn larvae of Trichinella spiralis were characterized in terms of molecular weight of protein, glycoprotein and lipoprotein contents, and immunochemistry. After the antigens were separated with SDS-PAGE and then followed by ultrasensitive silver staining, at least 40 bands of proteins were noted. Correspondingly, 28 bands of glycoproteins and 9 bands of lipoproteins were revealed as the similar gels were stained by the hypersensitive periodic acid silver and Nile's blue staining respectively. Six specific bands were recognized using polyclonal antibodies in the serum of rabbits immunized with antigens of newborn larvae by immunoblotting. All of them are glycoproteins. The components of the antigens with molecular weight (MW) 41.5 kd, 40 kd, 29.5 kd, 25 kd, 11 kd and 18 kd were found to be species specific and newborn larva stage-specific target antigen relevantly.

Animals↗
PubMed1990

[The measurement of p30 level in the normal human seminal plasma by the Beckman immunochemistry system using anti-30 serum].

This paper is the first report about the measurement of p30 level in the normal human seminal plasma by the Beckman immunochemistry system (ICS) using anti-p30 serum. The p30 levels of 108 samples of normal human seminal plasma were measured. The range of p30 level was 0.2996-4.3913 mg/ml. The square root transformation statistical analysis indicated that the coefficient of skewness was 0.0237 the coefficient of kurtosis was -0.8854, the p30 level in normal human seminal plasma fitted the square root normal distribution, the mean was 1.6236 mg/ml and the standard deviation was 0.1641 mg/ml.

Humans↗
PubMed1990

Ultrastructural immunochemistry of J chains in chickens.

Using ultrastructural immunochemistry, we have determined subcellular localization of J chain molecules in chicken splenic cells. The majority of J chain positive cells (JPC) were lymphoblast-like cells. The data show that J chains predominantly are localized in cytoplasm with a considerable amount distributed on the cell surface. In the cytoplasm, J chains were diffusely expressed. Furthermore, these J chain molecules were clearly seen as cluster type. In addition to the J chain localization of subcellular organelles as described above, J chains were partly found on perinuclear spaces. As J chains are key protein in B cell differentiation into immunoglobulin (Ig) producing cells, these findings might help for studying regulation of B cell differentiation in addition to revealing the molecular assembly of polymeric Ig.

Animals↗
PubMed1990

Automated immunochemistry.

A prototype immunostainer, featuring totally enclosed slide chambers, a reagent carousel and a microcomputer controlled fluid transfer system, was developed. The machine offers total flexibility in choice of primary and detection reagents for each slide and has been successfully used for the immunochemical demonstration of a variety of antigens in paraffin wax and blood smear preparations. It is considerably cheaper to use than manual immunochemistry and will be even cheaper in a production version currently under development.

Equipment Design↗
PubMed1992

Cytochrome b560 (QPs1) of mitochondrial succinate-ubiquinone reductase. Immunochemistry, cloning, and nucleotide sequencing.

Mitochondrial succinate-ubiquinone reductase is composed of two parts, a water-soluble succinate dehydrogenase and a two-polypeptide membrane-anchoring protein fraction (QPs). The larger polypeptide of QPs is believed to be associated with cytochrome b560 (QPs1). The structure of QPs1 was studied by immunochemistry and molecular cloning and sequencing. Antibodies against QPs1 were raised in rabbits, purified, and characterized by enzyme-linked immunosorbent assay and Western blotting. The purified antibodies inhibited 75% of the reconstitutive activity of QPs and reacted with both submitochondrial particles (SMP) and mitoplasts. The binding of these antibodies to SMP was greatly increased when succinate dehydrogenase was removed from SMP by alkaline treatment, indicating that QPs1 is a transmembranous protein and that some of its specific epitopes are covered by succinate dehydrogenase. Anti-QPs1 antibodies were used to screen one cDNA clone encoding QPs1 from a bovine heart cDNA lambda gt11 expression library. The cDNA insert is 946 base pairs with an open reading frame of 396 base pairs that encodes for 132 amino acid residues. The molecular weight of QPs1, calculated from the deduced amino acid sequence, is 14,320. Although the apparent molecular weight of QPs1, estimated by high resolution SDS-polyacrylamide gel electrophoresis, is approximately 11,000, the existence of a presequence was ruled out by mass spectrometric analysis of protein fragments. QPs1 is a very hydrophobic protein. Three probable membrane-spanning segments were revealed by a hydropathy plot of the sequence. QPs1 has a higher sequence similarity to the sdhC peptide of Escherichia coli than to the sdhC peptide (cytochrome b558) of Bacillus subtilis. Like the bacterial proteins, QPs1 has 2 conserved histidines at positions 34 and 90. The conserved nature and similar location of these 2 histidines, on the matrix-side surface of the membrane, suggest that they are involved in heme ligation of cytochrome b560.

Amino Acid Sequence↗
PubMed1992

Arrhenius vs. Ehrlich on immunochemistry: decisions about scientific progress in the context of the Nobel Prize.

This study forms part of a larger research project examining the election process for the Nobel prizes for Physiology or Medicine at the Karolinska Institute in Stockholm, and the role and function of the prizes in early 20th century Swedish and international medicine. The purpose of the study is to clarify the decision-making process which led to the Nobel prize for Paul Ehrlich in 1908, 'for work on immunity'. His award was preceded by the most dramatic conflict within the prize authority concerning any prizewinner prior to World War I, and thus is apt to illuminate both the implicit and explicit criteria and the strategies used in the prize deliberations. Ehrlich's chemical ideas on the immune response were criticized by the physical chemist Svante Arrhenius who recommended the application of his disciplines's methods and principles on immunological problems. This criticisms were brought into the Nobel prize debate by J.E. Johansson, a physiologist who asserted that Ehrlich's research was of little scientific value and therefore not worthy of a prize. Yet the majority of the Institute, led by its chairman, the chemist K.A.H. Mörner, succeeded in awarding Ehrlich. An analysis of the controversy shows it to be primarily based upon (1) a difference of scientific styles between the antagonists, resulting in incongruous definitions of immunology as a research field, and of the proper aims and methods of immunological studies. Other factors influencing the final decision were (2) the Institute's negative reaction to what was considered an intrusion in medical Nobel prize matters by a chemist, (3) Arrhenius' and Johansson's diverging views on what kind of work should be awarded a prize, and (4) Johansson's position as a non-conformist at the Karolinska.

Decision Making, Organizational↗
PubMed1986

Immunochemistry of the Lewis blood-group system: isolation and structures of Lewis-c active and related glycosphingolipids from the plasma of blood-group O Le(a-b-) nonsecretors.

Five different glycosphingolipid fractions (GL-3, 285 micrograms; GL-5, 1090 micrograms; GL-6, 615 micrograms; GL-7, 555 micrograms; and GL-8, 155 micrograms) have been isolated from 25 liters of plasma of O Le(a-b-) nonsecretors by means of ethanol extraction, several steps of Folch distribution, and reversed-phase, silicic acid, and ion-exchange column chromatography of native or peracetylated substances. Final purification, accomplished by preparative silica gel high-performance thin-layer chromatography, led to chromatographic homogeneity of GL-3 and GL-6. In the hemagglutination inhibition as well as quantitative passive hemagglutination techniques two of these substances (GL-3, GL-5) exhibited distinct, and the other three (GL-6-GL-8) very strong, Lec blood-group activities when tested against two different Lec antisera of human or goat origin. The fragments' structures were elucidated by fast atom bombardment and electron impact mass spectrometry of permethylated derivatives in order to determine molecular weight, sugar sequence, position of branching points, and type of oligosaccharide chains, as well as fatty acid and sphingosine patterns of the ceramide residue. Combined gas-liquid chromatography and mass spectrometry of partially methylated alditol acetates identified sugar composition and glycosidic linkages. Thus, the following structures could be established: (formula; see text) In contrast to the structurally homogeneous GL-3, minor amounts of 4-O-substituted GlcNAc pointed to a small contamination of GL-6 by branched type 2 ceramide nonasaccharide analogs. Glycolipids containing hepta- or nonasaccharides as in GL-3 or GL-6 could also be identified in fractions GL-5 (ceramide heptasaccharide) and GL-7 and GL-8 (ceramide nonasaccharide). These latter fractions revealed, however, distinct heterogeneity due to the presence of a small amount of either a type 2 analog of GL-3 (GL-5) or linear, mainly type 2, ceramide hexa- (GL-5, GL-7) or octasaccharides (GL-8). In addition to previous immunochemical communications the presented Lec active structures of GL-3 and GL-6 provide evidence that 3-fucosyl-N-acetyllactosamine in combination with a type 1 based oligosaccharide sequence and a 3,6-galactosyl branching point are essential parts of the Lec antigenic determinant (as marked in the formula of GL-6).

ABO Blood-Group System↗
PubMed1990

Sparteine metabolism capacity in human liver: structural variants of human P450IID6 as assessed by immunochemistry.

An antibody raised against rat P450dbl was used to examine the heterogeneity of the human enzyme involved in the sparteine/debrisoquine polymorphism. The extent to which the antibody was able to inhibit sparteine metabolism varied in different human livers (10-80%, n = 9) and reflected the amount of sparteine metabolism carried out by the polymorphic P450IID6 in individual liver specimens. The individual sample variation in inhibition by the antibody correlated with the inhibition caused by quinidine, a prototype competitive inhibitor of the P450IID6 enzyme active site. Western immunoblots of the liver microsomes confirmed that the variation in the inhibition of sparteine metabolism by this antibody reflected the amount of P450IID6 protein. In addition, a detailed study of one of the livers (K19) which demonstrated a lack of inhibition by the antibody was performed which confirmed the lack of P450IID6 in this liver specimen and suggested that the nascent sparteine metabolism activity was due to other forms of P450.

Animals↗