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Biomedical subjects

D Roelcke

Publications and source records attributed to D Roelcke.

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

Persistent cold agglutinins in AIDS and related disorders.

Eighty-one homosexual patients positive for HTLV-III antibody, including 19 with AIDS, 20 with chronic lymphadenopathy syndrome, 10 with AIDS-related complex (ARC) and 32 symptom-free individuals were assessed for the presence of cold agglutinins (CA). In 12 cases, CA were found; 4, 4, 2 and 2, respectively, in each of the above mentioned groups. Seven anti-I, 4 anti-i and 1 anti-Gd CA were identified. In 11 of 12 patients, CA were persistent. There were no differences between CA-negative and CA-positive patients with regard to the presence of other antibodies, anemia, frequency of intercurrent infections or development of lymphoproliferative neoplasia. It can be concluded that persistent synthesis of CA may be associated with the HTLV-III infection.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Saccharide structures of the mouse embryo during the first eight days of development. Inferences from immunocytochemical studies using monoclonal antibodies in conjunction with glycosidases.

Monoclonal anti-carbohydrate antibodies have been used in conjunction with glycosidases in immunofluorescence studies to derive information about the structures and in situ distribution of saccharides of the mouse embryo during the first 8 days of development. The salient findings are as follows: Branched poly-N-acetyllactosamine sequences of I-antigen type are detectable from the first day onwards and are widely distributed in cells of the endoderm, ectoderm and mesoderm. Linear poly-N-acetyllactosamine sequences of i-antigen type are detectable from the fifth day onwards in cells of all three lineages, but have a more restricted distribution than the sequences of I-type. Poly-N-acetyllactosamine sequences that are susceptible to digestion with endo-beta-galactosidase are the main carriers of the SSEA-1, C14 and the blood group B-like antigens, which have the following structures (Formula; see text) and are found in endoderm and ectoderm but not in mesoderm cells. In the trophoblast however, these antigens are borne on saccharides that are resistant to endo-beta-galactosidase. A proportion of the poly-N-acetyllactosamine structures in the endoderm and the ectoderm of the 5- and 6-day embryos may contain the following novel structures: (Formula; see text) in which antigenicities of SSEA-1 and C14 determinants are masked. There are several types of sialyl-oligosaccharides: those reactive with anti-Gd, which has a specificity for NeuAc alpha 2-3Gal beta 1-4GlcNAc sequence in the extraembryonic mesoderm and the heart; those reactive with anti-Pr2 but not with anti-Gd, which may correspond to other N-acetylneuraminic acid containing sequences such as NeuAc alpha 2-3Gal beta 1-3GalNAc or NeuAc alpha 2-6Gal in preimplantation embryos and in the yolk sac, neural ectoderm and mesenchyme of the 8-day embryo; those with other sialic acid forms or linkages that do not react with anti-Gd and Pr2; among these are sialosyl-i sequences in the extraembryonic ectoderm, and sialosyl-I sequences in most cell types during the first 8 days. The latter are the main poly-N-acetyllactosamine structures in the neural ectoderm of the 8-day embryo. The sequence Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc/GlcNAc, or cross-reactive structures, which bind FC10.2 antibody occur in the extraembryonic endoderm and yolk sac. The roles of specific carbohydrate structures as receptors during embryonic development and cell growth are important topics of current research.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1984

The reactivities of human erythrocyte autoantibodies anti-Pr2, anti-Gd, Fl and Sa with gangliosides in a chromatogram binding assay.

The thin layer chromatogram binding assay was used to study the reaction of several natural-monoclonal autoantibodies which recognize sialic acid-dependent antigens of human erythrocytes. Immunostaining of gangliosides derived from human and bovine erythrocytes was achieved with four autoantibodies designated anti-Pr2, anti-Gd, Sa and Fl, each of which has a different haemagglutination pattern with untreated and proteinase-treated erythrocytes and with cells of I and i antigen types. From the chromatogram binding patterns of anti-Pr2 with gangliosides of the neolacto and the ganglio series, it is deduced that this antibody reacts best with N-acetylneuraminic acid when it is alpha 2-3- or alpha 2-6-linked to a terminal Gal(beta 1-4)Glc/GlcNAc GlcNAc sequence and to a lesser extent when it is alpha 2-3-linked to a terminal Gal(beta 1-3)GalNAc sequence or to an internal galactose and when it is alpha 2-8-linked to another, internal N-acetylneuraminic acid residue. The other three antibodies differ from anti-Pr2 in their lack of reaction with glycolipids of the ganglio series. They react with the NeuAc(alpha 2-3)Gal(beta 1-4)Glc/GlcNAc sequence as found in GM3 and in glycolipids of the neolacto series, but show a preference for the latter, longer sequences. Thus all four antibodies react with sialylated oligosaccharides containing i type (linear) and I type (branched) neolacto backbones. Fl antibody differs from the other three in its stronger reaction with branched neolacto sequences in accordance with its stronger agglutination of erythrocytes of I rather than i type. The four antibodies show a specificity for N-acetyl- rather than N-glycolyl-neuraminic acid.

Animals↗
PubMed1984

Autoimmune hemolytic anemia by coexisting anti-I and anti-Fl cold agglutinins.

In association with atypical pneumonia, a patient developed acute severe autoimmune hemolytic anemia. Hemoglobin temporarily was only 7.0 g/100 ml, so that the patient needed red blood cell (RBC) transfusion. Hemolysis was found to be caused by high titer cold agglutinins (CA), which occurred transiently during the acute period of the disease. CA of two different specificities, anti-I and anti-Fl, were demonstrated in the patient's serum. Antibodies of the two specificities were clearly separated by absorption/elution experiments using neuraminidase (RDE)-treated RBC. They were distinguished by serologic means: Both anti-I and anti-Fl react more strongly with adult RBC than with newborn and i adult RBC; in contrast to anti-I, anti-Fl does not agglutinate RDE-treated cells. Inhibition experiments showed that I-active substances prepared from papainized RBC exhibited both I and Fl antigenic activity. By RDE-treatment of I-active substances, Fl-activity was markedly reduced, while I-activity was increased.

Adult↗
PubMed1984

Reaction of anti-Gd, anti-Fl and anti-Sa cold agglutinins with p erythrocytes.

Among four anti-Gd cold agglutinins two showed a slight preferential reaction with p erythrocytes, two did not. Anti-Fl and anti-Sa cold agglutinins, sharing some serologic characteristics with Gd antibodies, showed no preferential reactions with p cells. The findings point to different fine specificities of monoclonal anti-Gd cold agglutinins.

Agglutinins↗
PubMed1984

Simultaneous occurrence of anti-F1 and anti-I cold agglutinins in a patient's serum.

The second example of anti-F1 cold agglutinins recognizing a developmentally regulated antigen like I is described. The antibody occurred transiently and simultaneously together with an anti-I cold agglutinin. Although anti-F1 and anti-I specificities are entirely different, the data on the biochemistry of F1 and I antigenic determinants provide an explanation for the simultaneous occurrence of anti-F1 and anti-I cold agglutinins in connection with a poly- or oligoclonal autoimmune response.

Anemia, Hemolytic, Autoimmune↗
PubMed1984

Cold agglutinin Vo. An IgM lambda monoclonal human antibody recognizing a sialic acid determined antigen fully expressed on newborn erythrocytes.

An IgM lambda cold agglutinin reacted preferentially with newborn (i cord) and i adult erythrocytes. The whole serum of patient Vo and the antibody isolated by warm elution reacted moderately with native and neuraminidase-treated red cells but strongly with papainized red cells. Papainization of erythrocytes enhanced markedly the susceptibility of the corresponding antigen not only to antibody binding but also to the action of neuraminidase, indicating that sialic acid is the immunodominant component of the cryptic antigen. The cold agglutinin Vo is the first example of a human monoclonal antibody recognizing a sialic acid-dependent, developmentally regulated antigen fully expressed on newborn erythrocytes.

Agglutinins↗
PubMed1983

Characterization of an epitope (determinant) structure in a developmentally regulated glycolipid antigen defined by a cold agglutinin Fl, recognition of alpha-sialosyl and alpha-L-fucosyl groups in a branched structure.

The antibody Fl shows preferential reactivity with adult erythrocytes over newborn erythrocytes, and its reactivity is abolished by sialidase treatment of the erythrocyte. The antibody was found to recognize binary determinants linked to the branched lacto-N-isooctaosylceramide (formula; see text) The presence of an N-acetylneuraminyl group at one end and L-fucosyl group at the other end is essential for the reactivity of the antibody. A substitution at the penultimate D-galactosyl residue of one of the chains with an alpha-D-(1 leads to 3)-linked 2-acetamido-2-deoxygalactosyl or galactosyl group did not inhibit the reactivity of the antibody. The new blood group A- and B-active, branched gangliosides are also isolated and characterized.

ABO Blood-Group System↗
PubMed1983

Monoclonal anti-idiotype antibodies against lymphoma-associated cold agglutinins.

Hybridomas secreting monoclonal antibodies against purified cold agglutinins (CA) from lymphoma patients were screened by a cold hemagglutination inhibition test. Supernatants from positive clones were further tested against several purified CA and paraproteins of different immunoglobulin (Ig) classes. It was shown that most monoclonal antibodies raised by immunization with CA had reactivity against the constant region of IgM. However, clone H-1 produced an anti-idiotypic antibody that reacted exclusively with the CA used for immunization. Using this anti-idiotype antibody, the idiotype could be demonstrated on 25% of the patient's peripheral mononuclear cells. So far, the idiotype could not be demonstrated on the patient's T-cells. Monoclonal antibodies against lymphoma idiotypes are powerful tools for studying the immunobiology of these malignancies and may be useful as specific therapeutic reagents.

Aged↗
PubMed1983

A new method for the preparation of anti-idiotypic antibodies against six different human cold agglutinins.

A method based on sequential immunoadsorption for the preparation of a highly specific antibody directed against the idiotypic determinant of human cold agglutinins (CA) is described. In the present study, human cold agglutinins (CA) were used as a model, but the method can easily be adapted for the preparation of anti-idiotypic antibodies against other monoclonal human immunoglobulins. Since regenerable immunoadsorbents were used, the isolation can be accomplished even with rather low amounts of the respective immunoglobulin.

Agglutinins↗
PubMed1983

Glycophorin A inhibits lysis by the complement attack phase.

A glycoprotein from human erythrocyte membranes has been found to inhibit lysis of target cells by the attack-phase components C5-C9 from human complement. The inhibiting molecule was purified and identified as glycophorin A. Thus, glycophorin A may have a regulatory function in the lytic complement attack on isologous cells.

Animals↗
PubMed1983

Influence of Lewis and other blood group systems in kidney transplantation.

In 167 first cadaver kidney recipients and their donors the blood groups ABO, Rhesus, Lewis, MN, Ss, P, Kell and Duffy were determined. The influence of incompatibility in each system as well as of simultaneous presence of several mismatches was analysed. Whereas one-year graft survival of Lewis-compatible grafts was 67 per cent (p = 0.02). The other blood groups showed no significant effect on graft outcome. Cumulative red cell incompatibilities, however, led to decreased survival rates. One-year graft survival in the group with greater than or equal to 4 incompatibilities was only 51 per cent versus 69 per cent in transplants with less than 4 incompatibilities (18% difference, p less than 0.01). When the Lewis system was excluded from analysis, the difference in survival rates was reduced to only six per cent. These data indicate that cumulative incompatibilities of red cell antigens have an unfavourable effect on graft survival. Of the different blood groups, the Lewis system is of major importance.

Blood Group Antigens↗
PubMed1982

Glycosphingolipid receptors for anti-Gd and anti-p cold agglutinins.

Anti-Gd and anti-p cold agglutinins exhibit similar serological properties: neuraminidase treatment of erythrocytes greatly reduces their agglutinability by these antibodies and protease treatment enhances their agglutination. We reported previously that an anti-p cold agglutinin was inhibited by sialosyllactoneotetraosylceramide, NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)Glc-Cer, the most abundant ganglioside of human erythrocytes. We now report that two less abundant gangliosides are more potent inhibitors of this antibody, and of the anti-Gd antibodies, than sialosyllactoneotetraosylceramide. These two gangliosides have the same carbohydrate chain, NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)Glc(SNH), but they differ in their ceramide moiety. The principal fatty acid of SNH-1 is C16:0, whereas SNH-2 contains a predominance of C22:0, C24:0 and C24:1. No inhibition was produced by the ganglioside, NeuAc(alpha 2-6)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)Glc-Cer. Another monoclonal cold agglutinin, Sa, which shares some serological properties with anti-Gd cold agglutinins, was not inhibited by any of these gangliosides.

Agglutinins↗
PubMed1982

A "spontaneous" cold-reactive IgM antibody with anti HLA-B8 specificity in a patient with multiple sclerosis.

A case of a 35-year-old female with multiple sclerosis is reported who developed without apparent prior sensitization a lymphocytotoxic antibody with anti-HLA-B8 specificity. The antibody persisted for several years with the same titer. The cytotoxic activity of the patient's serum was contained within the IgM fraction. The antibody reacted optimally at low temperature, exclusively against lymphocytes homozygous for HLA-B8. In B8-heterozygous cells, cytotoxic reactions were obtained only following enzymatic pretreatment. The antibody's binding avidity was weak; for its complete absorption, many times more B8-positive lymphocytes or platelets were needed than for a "normal" anti-B8 antibody of the same titer. In HLA redistribution and blocking experiments, it was demonstrated that the antigenic determinant recognized by this antibody is carried by the B8 molecule. It is unclear whether "spontaneously" occurring cold-reactive IgM antibodies with HLA specificity are induced by viral agents or whether they reflect "spontaneous" clonal lymphocyte proliferation.

Absorption↗
PubMed1982

Identification of a cold agglutinin with anti-Pr3 specificity.

An apparent monoclonal IgM, kappa-cold agglutinin with anti-Pr specificity was detected in the serum of a 38-year old woman. Haemagglutination inhibition studies disclosed the subspecificity anti-Pr3, since the cold agglutinin was strongly inhibited by carbodiimide-treated erythrocyte glycoproteins. Studies with animal cells showed that the corresponding Pr3 determinant was found only on human red cells. This is in contrast to earlier findings and indicates that distinct fine specificities within anti-Pr3 antibodies might well exist.

Adult↗