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R L Raison

Publications and source records attributed to R L Raison.

At least 55 records · Page 3Linked to original sources
PubMed1985

Structural analysis of the myeloma-associated membrane antigen KMA.

kappa-Myeloma antigen (KMA) was immunoprecipitated from lactoperoxidase-radioiodinated HMy2 lymphoblastoid cells by using monoclonal antibody K-1-21 and was analyzed by SDS-PAGE. Under reducing conditions, two major subunits of Mr approximately 26,000 and Mr approximately 42,000, and minor components of Mr approximately 28,000, 31,000, and 36,000 were observed. The Mr approximately 26,000 subunit was identical to kappa-light chains from HMy2 surface IgG in apparent m.w., isoelectric point, and staphylococcal V-8 protease peptide map, but was not precipitated in association with Ig heavy chain. The Mr approximately 42,000 component was homologous to rabbit skeletal muscle actin by peptide mapping with staphylococcal V-8 protease. The cell surface origin of the immunoprecipitated antigen was confirmed by demonstrating lactoperoxidase dependence of iodination and complete removal from the cell surface after pronase treatment of viable cells. Thus, cell surface expression of KMA is the result of membrane association of non-heavy chain-linked kappa-light chains, possibly in noncovalent association with actin.

Actins↗
PubMed1984

The surface expression of a tumor-associated antigen on human kappa myeloma cells.

The monoclonal antibody K-1-21 defines an antigen, KMA (kappa myeloma antigen) on the surface of human kappa myeloma cells. K-1-21 also recognizes human kappa light chains in free form but not when covalently bonded to heavy chains. To examine the relationship between KMA and this determinant on free kappa chains, the surface expression of KMA was examined on the IgG, kappa myeloma line LICR LON/HMy2 (HMy2). No patching or capping was observed in the presence of K-1-21 alone, but KMA could be capped if the cells were incubated with K-1-21 followed by fluorescein isothiocyanate-conjugated sheep F(ab')2 anti-mouse immunoglobulin. Capping was not affected by the inhibitors calcium ionophore or dibucaine. When IgG molecules were removed from the cell surface by capping with anti-IgG antiserum both KMA and free kappa light chains could still be detected with K-1-21 and a polyvalent anti-kappa antiserum, respectively. By contrast, after removal of all surface kappa chains with the polyvalent anti-kappa serum, no staining was observed with K-1-21 indicating that KMA may be an epitope on free kappa chains inserted in the membrane of kappa myeloma cells but absent from normal cells. KMA cell surface expression varied with the stage of the cell cycle. Flow cytometric analysis of K-1-21-stained HMy2 cells from either continuous cultures or from elutriated fractions enriched for various cell cycle phases showed that, within the cycling population, cells in G2 + M expressed KMA at a higher frequency and density than did cells in G1.

Antibodies, Monoclonal↗
PubMed1984

Immunoglobulin-bearing blood leucocytes in the Pacific hagfish.

The occurrence of immunoglobulin (Ig) bearing leucocytes in the blood of the Pacific hagfish, Eptatretus stoutii , was examined using a murine monoclonal antibody (45.3) and a rabbit antiserum specific for hagfish serum Ig. Binding of antibody 45.3 to hagfish leucocytes assessed by radioimmunoassay was inhibited by preincubation of antibody with purified serum Ig thus verifying the presence of cell surface Ig cross reactive with serum Ig. The monoclonal antibody identified approximately 65% of blood leucocytes as Ig+ve while the rabbit antiserum indicated 81% Ig+ve cells. Both antibody preparations failed to react specifically with cells from mouse, horned shark, tunicate or sea star; this indicates the distinctive nature of hagfish Ig. The high percentage of blood cells bearing surface Ig in the hagfish raises the possibility that lymphocyte divergence to separate B and T pathways may not have occurred in this most primitive vertebrate. Alternatively, an Ig-like specificity characteristic of both "T" and "B" lymphocytes may have been detected. In any event, a subset of Ig negative leucocytes is evident in hagfish.

Animals↗
PubMed1983

A tumor-associated antigen specific for human kappa myeloma cells.

A monoclonal antibody (K-1-21) raised against a kappa Bence Jones protein exhibits unique binding properties to malignant plasma cells. K-1-21 is an IgG1 kappa antibody that reacts with human kappa light chains in free form, but shows no reactivity with heavy chain-associated kappa light chains. By immunofluorescence, K-1-21 binds to the surface of LICR LON/HMy2 (HMy2) kappa myeloma cells and to plasma cells from a majority (8/11) of patients with various types of kappa myeloma; it did not bind to the surface of normal cells, nor to malignant cells of non-kappa myeloma origin. Flow cytometry analysis of K-1-21 binding to HMy2 cells indicated that the surface reactivity of K-1-21 could be completely inhibited by preincubation of the antibody with purified kappa light chains, whereas no inhibition occurred after preincubation with lambda chains or intact human IgG. Thus, the epitope recognized by K-1-21 on the cell surface may be similar, if not identical, to the determinant recognized on soluble free kappa light chains, and constitutes a tumor-associated antigen with selectivity for kappa myeloma cells. K-1-21 may therefore have clinical potential in patients with kappa myeloma.

Animals↗
PubMed1983

Standardization of antigen E in ragweed pollen extracts using a monoclonal antibody-based enzyme immunoassay.

A hybridoma-derived monoclonal IgG antibody specific for ragweed AgE was used to develop a competitive binding enzyme immunoassay suitable for quantitation of antigen E levels in ragweed pollen extracts. The assay was capable of detecting as little as 30 ng/ml AgE in crude pollen extracts. The monoclonal antibody was shown to react with AgE present in commercial pooled pollen extracts from a number of ragweed species as well as a laboratory extract from a single species. In contrast to previous conventional xenoantisera, it could distinguish true ragweed (Ambrosia sp) from false ragweed (Franseria sp). The use of monoclonal antibodies in assay systems such as this offers a reproducible and widely applicable method for allergen standardization.

Allergens↗
PubMed1983

Monoclonal antibodies directed against skeletal muscle actin.

The development of a monoclonal antibody directed against rabbit skeletal muscle monomeric actin is described. The production of the monoclonal antibody followed a standard hybridoma technique, the antibody being purified by affinity chromatography. It was found to be of the IgM class. Antibody specificity for rabbit skeletal actin was demonstrated by radioimmunoassay. The antibody failed to bind to actin in Western Blot experiments, presumably due to modification of the antigenic determinant on actin during the Western Blot procedure. The antibody was also shown to bind to two other isotypes of actin, i.e. actin from squid mantle muscle and bovine myocardium.

Actins↗
PubMed1982

Loss of secretion in mouse-human hybrids need not be due to the loss of a structural gene.

Three cloned mouse-human lines (B1-29, E2-42, and A2-31) secreting human immunoglobulin (Ig) were obtained from a fusion between the mouse myeloma line NS-1 and human tonsillar lymphocytes stimulated in vitro with pokeweed mitogen. One line, B1-29, has continued to secrete human IgG for a period of 2 yr in culture. This line was recloned three times to give a panel of secreting and nonsecreting subclones. Most of the nonsecreting subclones had also lost surface Ig. The structural genes for human Ig heavy chains have been provisionally assigned to chromosome 14, which also encodes the enzyme nucleoside phosphorylase. Human nucleoside phosphorylase was detected in all secreting and nonsecreting B1-29 subclones, indicating the presence of human chromosome 14. The retention of chromosome 14 in nonsecreting clones implied that the structural genes for human Ig were A2-31 and E2-42, which had stopped secreting, an attempt was made to restimulate the secreting of human Ig with mitogens A2-31 was unique among the cell lines examined, in that chromosome 14 could not be detected by an isoenzyme marker. Lipopolysaccharide, at an optimum dose of 10 micrograms/ml, restimulated these nonsecreting hybrid lines to secrete human IgG in levels up to 0.7 micrograms/ml. Loss of Ig secretion may not therefore be caused by loss of Ig structural genes.

Animals↗
PubMed1982

A comparison of two anti-neuraminidase monoclonal antibodies by complement activation.

The specificities of two anti-neuraminidase monoclonal antibodies have been compared by their ability to fix complement. They were found to differ to some extent in their reactivity with a range of N2 influenza virus. Thus, as in the case of anti-hemagglutinin antibodies, anti-neuraminidase monoclonal antibodies are able to detect subtle structural changes in the vital antigen. Although both monoclonal antibodies fixed complement with intact virus, neither one fixed complement when complexed with isolated neuraminidase "heads".

Animals↗
PubMed1982

Effect of monoclonal anti-neuraminidase antibodies on the kinetic behavior of influenza virus neuraminidase.

Neuraminidase from the recombinant influenza virus A/NWSHA-Tokyo/3/67NA HON2 has been shown to exhibit non-Michaelis-Menten kinetics. The multiphasic behaviour was demonstrated for both the isolated neuraminidase heads and for the intact virus. Interaction of the enzyme with two monoclonal anti-neuraminidase antibodies (WANA 1 and RANA 1), which recognize separate antigenic determinants on the molecule, resulted in hyperbolic kinetic behaviour. While both antibodies abolished the multiphasic kinetics of the enzymic reaction, only WANA 1 altered the Vmax and Km values, indicating that it may in some way inhibit the interaction of enzyme and substrate.

Antibodies, Monoclonal↗
PubMed1982

Monoclonal antibody against human somatomedin-C/insulin-like growth factor-I.

A monoclonal IgG3 antibody produced by mouse hybridoma shows high specificity for human somatomedin-C (SM-C) and insulin-like growth factor-I (IGF-I). The apparent Ka for SM-C is 1.7 x 10(10) M-1. At 1:2000 final dilution, culture medium from antibody-producing cells binds 35-40% of radioiodinated SM and IGF-I tracers, while similar binding is seen with ascites fluid from tumor-bearing mice at 1:200,000 dilution. Rat SM, multiplication stimulating activity, IGF-I C-peptide and human insulin show little or no crossreactivity, while IGF-II has 7%, and IGF-I 70%, of the potency of SM-C. Of a variety of species tested, acid-ethanol extracted guinea pig serum has the greatest immunoreactivity, and extracts of rabbit, rat and mouse serum have the lowest activity. Human plasma extracts give displacement curves parallel to purified SM, and vary in potency depending upon the GH status of the donor. These results suggest that this antibody will be of value for SM-C/IGF-I radioimmunoassay.

Acromegaly↗
PubMed1978

Characterization of immunoglobulin from the Pacific hagfish, a primitive vertebrate.

Antibodies to group A streptococcal carbohydrate, demonstrable by radioimmunoassay, were elicited in Pacific hagfish, Eptatretus stoutii, after prolonged immunization with whole cell vaccine. This hagfish antibody, isolated by ion-exchange chromatography of immune serum, exhibited a single precipitin line after immunoelectrophoresis against rabbit antiserum to hagfish serum. The isolated antibodies retained high binding activity for the streptococcal carbohydrate, but lacked the natural hemagglutinating activity found in both nonimmune and immune sera. Analysis by gel filtration in neutral and dissociating buffers and by sodium dodecyl sulfate/polyacrylamide gel electrophoresis under nonreducing conditions indicated an intact molecule of molecular weight approximately 160,000 that may be noncovalently associated in a polymer of higher molecular weight. Heavy chains of mobility identical to that of murine mu chains and light chains of mobility significantly slower than murine lambda chains were obtained after sodium dodecyl sulfate gel electrophoresis under reducing conditions. Instability of the tertiary structure of the antibody molecule was indicated by partial dissociation in buffers containing sodium dodecyl sulfate and by dissociation at low concentrations of reducing agent. In contrast to its well-developed system of cell-mediated immunity, only a minimal system of circulating antibody production is evident in this primitive fish. No evidence for divergence of cyclostome lymphocytes into separate T- and B-cell systems has yet been discerned.

Animals↗
PubMed1977

Immunological specificity and memory in a scleractinian coral.

Tissue transplantation immunity with a specific memory component is demonstrated in populations of Montipora. This highly discriminating immunoreactivity derives from extensive allogeneic polymorphism of histocompatibility (H) markers. An H system of immunorecognition is postulated to have originated in multicellular invertebrates probably beginning with coelenterates.

Animals↗
PubMed1977

Structural restriction and similarities of the light chains of antibodies to group B streptococcal carbohydrate produced in a single rabbit.

Comparison of the amino acid compositions, N-terminal amino acids and tryptic peptide maps of two L chains (145 LI and 145 LII) derived from antibodies produced in a single rabbit to group B streptococci indicates a high degree of sequence homology of the two chains. Furthermore, comparison of these data with similar analysis of L chains prepared from pooled antibodies to group B streptococci indicates a high degree of V region restriction in the L chains of antibodies elicited by hyperimmunization with streptococci.

Amino Acids↗
PubMedDate not supplied

IgM expressed by leukemic CD5(+) B cells binds mouse immunoglobulin light chain.

Mouse immunoglobulin (Ig) molecules have previously been shown to bind to the surface of CD5(+) B cells from patients with B-cell chronic lymphocytic leukemia (B-CLL). The results indicated that surface IgM was involved in the interaction and suggested the phenomenon was an example of the polyreactive binding capacity of the surface Ig (sIg) expressed by these malignant cells. This article describes the further characterization of the interaction between human IgM and mouse Ig molecules and subunits. Mouse Ig molecules of both kappa and lambda light chain classes bound to the B-CLL cell surface. The dissociation constant for the interaction of mouse IgG1 (K121) with the B-CLL cell surface was 3.6 x 10(-7) M. To confirm the involvement of the human IgM expressed by the B-CLL cells in the interaction, the malignant cells were stimulated in vitro to induce secretion of human IgM. Enzyme immunoassay was used to show that secreted human IgM bound to intact mouse Ig, as occurred with the cell surface analysis. The mouse Ig epitope recognized by the purified secreted human IgM was shown by Western blot analysis to be located on the light chain of the mouse Ig molecule and to be conformationally dependent. K121 light chain was cloned and expressed in E. coli and the recombinant light chain bound to the surface of CLL B cells. The results confirm that human IgM is the reactive ligand in the interaction with mouse Ig and indicate that the interaction of polyreactive IgM with mouse IgG occurs via the light chain component of IgG.

Animals↗
PubMedDate not supplied

Chemotactic responses of hagfish (Vertebrata, Agnatha) leucocytes.

The chemotactic responses of hagfish leucocytes were tested using a variety of chemoattractants. Leucocyte migration was significantly enhanced by purified mammalian complement anaphylotoxin (C5a) and LPS-activated hagfish plasma. Checkerboard analyses confirmed that the responses of leucocytes to both of these chemoattractants were directed along concentration gradients (chemotaxis) and did not result from accelerated random movement (chemokinesis). Chemotaxis was undertaken by leucocyte fractions that were enriched in granulocytes, the predominant phagocytic cells of hagfish. The data suggest that chemotactic mechanisms may have been conserved during evolution to such a degree that mammalian chemoattractants can bind and activate chemotactic receptors on hagfish leucocytes. Moreover, hagfish appear to express plasma proteins that are structurally and functionally homologous to mammalian complement anaphylotoxins.

Animals↗