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H Rumpold

Publications and source records attributed to H Rumpold.

At least 91 records · Page 5Linked to original sources
PubMed1985

Patients with a deficiency of natural killer cell activity lack the VEP13-positive lymphocyte subpopulation.

Many patients with B-type chronic lymphocytic leukemia (CLL) exhibit a profound defect in their natural killer (NK) cell activity, the basis of which is still obscure. Hence, we analyzed the NK cells from peripheral blood samples from 11 patients with CLL for phenotype and function, after removal of the leukemic cells with a monoclonal antibody (BA-1) plus complement. Phenotypic analysis of these nonleukemic cells with monoclonal antibodies (MoAbs) against NK cells revealed that the CLL patients had higher percentages of HNK-1-positive cells (23.5% compared to controls with 14.7%). In contrast, VEP13-positive cells were absent or low in seven patients (0.8% compared to controls with 11.2%) and normal in four patients (10.5%). When testing NK cell activities against K562 or MOLT 4 target cells, patients with no or minimal numbers of VEP13-positive cells were found to be deficient, while patients with normal percentages of VEP13-positive cells had NK cell activity comparable to controls. Isolation by fluorescence-activated cell sorter of HNK-1-positive cells from patients lacking VEP13-positive cells and NK cell activity indicated that the majority of the HNK-1-positive cells in these patients had the large granular lymphocyte morphology that is characteristic of NK cells. Thus, the deficiency of NK cell activity in CLL patients appears to result from the absence of cells carrying the VEP13 marker.

Antibodies, Monoclonal↗
PubMed1985

Expansion of a minor subpopulation of peripheral blood lymphocytes (T8+/Leu 7+) in patients with haemophilia.

Immunological analysis of peripheral blood mononuclear cells (PBM) was performed in 20 patients with haemophilia A or B. One of the patients had never received clotting factor substitution in his life. Six different sources of lyophilized clotting factor were used for the other patients, but every given patient received factor from one source, exclusively. None of the patients exhibited lymphadenopathy and only one suffered from local bacterial infection. Mononuclear cell counts were within the normal range and mitogen stimulation with phythaemagglutinin (PHA) and concanavalin A (Con A) was found normal in all but two patients. Ratios of helper and suppressor cells (T4/T8) were below 1.0 in 10 of the patients. Some of these patients had a relative increase of T8+ cells and at the same time of Leu 7+ (natural killer (NK)/suppressor) cells. Double-marker analysis revealed that the subpopulation of cells expressing both the T8 and the Leu 7 antigen, which on the average accounted for 2.1% of the mononuclear cells in controls, was increased 4.5 fold (9.1%) in haemophilia patients. One patient exhibited 37.8% T8+/Leu 7+ double-marker cells. VEP13+ cells (active NK cells) were decreased below the normal range in 11 of the patients. Abnormal values for lymphocyte subsets were found in every treatment group. The patient who had never received any clotting factor exhibited normal values in all respects. In an additional set of patients, those with increased percentage of T8+/Leu 7+ cells exhibited decreased NK cell activity indicating that the T8+/Leu 7+ cells are not active NK cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1984

Selective inhibition of natural killer activity by the monoclonal antibodies OKT10 and VEP10 at the single cell level.

The monoclonal antibodies, VEP10 and OKT10, which have been shown to recognize determinants on human natural killer (NK) cells, inhibit large granular lymphocyte (LGL) NK activity against K562, MOLT4, and CEM tumor target cells in the single cell conjugate agarose assay. Inhibition of NK activity by monoclonal antibodies was expressed independently of effector-target cell binding, as inhibitory activity could be demonstrated when the monoclonal antibodies VEP10 and OKT10 were added to preformed conjugates or to the LGLs and targets prior to the binding event. In addition, this inhibition was exerted on the effector cell and not the target cell since VEP10 and OKT10 did not react with determinants on K562 target cells. Furthermore, the 4F2 monoclonal antibody, which reacted with determinants on the LGL and all of the targets used, effected no inhibition of NK activity. Inhibition of killing by OKT10 and VEP10 was specific to endogenous NK activity since the same antibodies did not inhibit antibody-dependent cellular cytotoxicity (ADCC), mixed lymphocyte-generated NK, or cytotoxic T lymphocyte (CTL) activities.

Antibodies, Monoclonal↗
PubMed1984

The Fc receptor for IgG on human natural killer cells: phenotypic, functional, and comparative studies with monoclonal antibodies.

We compare five monoclonal antibodies ( B73 .1, 3G8 , Leu- 11a , Leu- 11b , and VEP13 ) that react with natural killer (NK) cells and polymorphonuclear cells (PMN). We show that all of these antibodies are directed against and inhibit the functional properties of the receptor for the Fc portion of IgG (FcR). Modulation of the FcR on NK cells after reaction with immune complexes induces the disappearance of the antigen(s) recognized by each of the five antibodies. Conversely, the antibodies block binding of IgG-sensitized erythrocytes to the NK cells and PMN and inhibit their ability to mediate cytotoxicity against antibody-sensitized tumor target cells. By using two-color immunofluorescence techniques, we characterize directly the lymphocyte population recognized by these antibodies and show that it is a homogeneous subset that does not bear markers of either B or T cells, with the exception of the 33,000 dalton antigen characteristic of suppressor/cytotoxic T cells present in 20 to 50% of the cells, and the 45,000 dalton receptor for sheep erythrocytes present on 80 to 90% of the cells. The phenotype of the cells reacting with the monoclonal antibodies corresponds to that of NK cells. Cross-competition experiments indicate that these antibodies detect at least two distinct epitopes on FcR, one ( B73 .1) preferentially expressed on NK cells and one or more ( 3G8 /Leu- 11a /Leu- 11b / VEP13 ) preferentially expressed on PMN. The lack of reactivity of these antibodies with B cells suggests that human B cells bear a different FcR from that on NK cells and PMN.

Antibodies, Monoclonal↗
PubMed1984

The use of VEP13 monoclonal antibody for definition of natural killer cells: spontaneous killer cells directed against fresh human leukaemia cells carry the VEP13 antigen.

VEP13, an IgM monoclonal antibody (MoAb), produced against human large granular lymphocytes, is able to deplete natural killer (NK) cell activity in complement-dependent lysis. Here we report that VEP13 also reacts with the majority of interferon (IFN) activated NK cells. By contrast cytotoxic activity of unstimulated monocytes and cytotoxic T cells directed against allogeneic lymphocytes were unaffected by VEP13 plus complement treatment. Thus among the major types of cytotoxic cells VEP13 selectively reacts with NK cells and hence can be employed to identify these cells. We therefore used VEP13 in complement-dependent lysis and FACS separation to analyse NK cells involved in enhanced killing of fresh leukaemia cells. Spontaneous cell-mediated lysis of human leukaemia cells was enhanced in two ways: (a) effector cells were pre-treated with beta-IFN and (b) leukaemia cells were pre-treated with a pulse of actinomycin D. In complement-dependent lysis VEP13 removed all NK cell activity of IFN activated PBM against untreated and against ActD pre-treated leukaemia cells. FACS separation of VEP13 positive cells further supported this finding, in that all activity of IFN activated NK cells against actinomycin D pre-treated targets was found in the VEP13 positive fraction. Thus enhanced killing of fresh human leukaemia cells appears to be mediated VEP13 positive NK cells which are distinct from cytotoxic T cells and cytotoxic monocytes.

Antibodies, Monoclonal↗
PubMed1984

The relationship of HNK-1 (Leu 7) and VEP13 antigens on human cells mediating natural killing.

The NK cell associated antigens defined by the two monoclonal antibodies, HNK-1 (anti-Leu 7) and VEP13, were investigated for their mutual expression on peripheral blood lymphocytes of healthy donors. In double labelling experiments only 6 +/- 3.9% of peripheral blood lymphocytes (PBL) were found to carry both markers. When VEP13+ cells were enriched by rosette formation using VEP13 coated ox red blood cells all the NK activity was recovered in the VEP13+ cell preparation, whereas the VEP13- subset was devoid of it, despite of the fact that there was a remainder (7-13%) of HNK-1+ cells. These VEP13- HNK-1+ cells were found to also bear the T3 antigen but lack the M1 antigen. Thirty-eight to sixty-eight per cent of VEP13+ enriched cell population expressed the HNK-1 antigen too. When these cells were further separated into HNK-1+ and HNK-1- cells by means of the FACS thus yielding the VEP13+ HNK-1+ and VEP13+HNK-1- subsets, it could be demonstrated that both populations were able to mediate natural killing against K-562 target cells thus indicating existence of an HNK-1- natural killer cell population. Investigating lymphocytes from a patient suffering from a leukaemia in which 75% of cells were of LGL morphology, 32% of cells were found to be HNK-1+ while 76% of cells were shown to bear the VEP13 antigen, thus revealing a similar phenotype as observed in normal individuals. Our results indicate the existence of a HNK-1- VEP13+ natural killer cell population.

Antibodies, Monoclonal↗
PubMed1983

[Extrinsic allergic alveolitis: comparison of 2 methods (Ouchterlony gel precipitation and ELISA) for antibody detection in routine diagnosis].

Sera from 58 patients with suspected extrinsic allergic alveolitis (EAA) were tested in parallel by the double diffusion test and the "enzyme-linked immunosorbent assay (ELISA)" using 10 different antigen solutions (extracts from thermophilic actinomycetes, various mycetes, pigeon serum, pigeon droppings and the wheat weevil sitophilus granarius). The ELISA technique was more sensitive than the double diffusion test in detecting antibodies to the panel of antigens used. However, by using several antigen dilutions the number of sera positive sera with the double diffusion test increased and an overall correlation of 93.1% with the ELISA was achieved. The results of the study are discussed with regard to the advantages and disadvantages of both test systems for the in vitro diagnosis of EAA.

Adult↗
PubMed1983

Marker of peripheral blood granulocytes and monocytes of man recognized by two monoclonal antibodies VEP8 and VEP9 involves the trisaccharide 3-fucosyl-N-acetyllactosamine.

Two hybridoma antibodies (VEP8 and VEP9) raised against the promyelomonocytic leukemia cell line HL60 have previously been shown to distinguish human granulocytes and monocytes from other cells of the peripheral blood. We report here that both antibodies recognize the carbohydrate structure 3-fucosyl-N-acetyllactosamine with the following sequence: (formula; see text) This structure is the same as that recognized by a hybridoma antibody against mouse teratocarcinoma cells (anti-SSEA-1) which recognizes an early embryonic antigen in the mouse. Until recently this carbohydrate structure was considered to be rare among glycoproteins and glycosphingolipids. However, there is a growing list of human and animal glycoproteins in which this sequence has been detected by chemical and immunochemical methods. In this article we survey this information and discuss how this and other carbohydrate structures behave as differentiation- or tumor-associated antigens.

Animals↗
PubMed1983

Regulation of purine uptake in normal and neoplastic cells.

Purine bases and purine nucleosides pass the cell membrane by facilitated diffusion. For purine bases two different carrier proteins seem to exist. Purine bases are trapped intracellularly immediately after passage of the cell membrane by the action of purine phosphoribosyltransferases (PRTs). Comparison of kinetic data of transport and intracellular enzyme reactions shows that intracellular metabolism is rate limiting for the whole uptake process. Since phosphate stimulates the uptake of bases, limited availability of phosphoribosylpyrophosphate (PRPP) might play a regulatory role. Purine nucleosides apparently enter cells via a common carrier. Of the nucleosides under investigation, only adenosine was taken up in significant amounts. Uptake of adenosine is mainly determined by the ratio of adenosine deaminase (ADA) and adenosine kinase (AK) activities. For uptake of purine nucleotides sequential action of ecto-5'-nucleotidase (ecto-5'-NT), nucleoside carrier and intracellular metabolism is necessary. Cells without ecto-5'-NT activity did not accumulate radioactivity from nucleotides. Proliferating neoplastic cells (K 562 and HL 60 cells) showed enhanced uptake of purine bases and nucleosides, when compared to quiescent cells (erythrocytes and granulocytes). From initial rates of uptake and intracellular enzyme activities it could be concluded that this enhanced uptake was due to alterations of enzyme pattern in the neoplastic cells.

5'-Nucleotidase↗
PubMed1983

Phenotypes of human large granular lymphocytes as defined by monoclonal antibodies.

Four monoclonal antibodies VEP8, VEP9, VIM-D5, VIB-C5 against antigens expressed on human mature myeloid cells (polymorphonuclear leukocytes [PMNL] and/or monocytes) as well as on immature cells in the bone marrow were tested for reactivity with cell preparations highly enriched for large granular lymphocytes (LGL). These cells are known to be the main effector cells responsible for natural killer (NK) cell activity in human peripheral blood. Using indirect membrane immunofluorescence (IMF), none of these antibodies showed any reactivity at all. In addition, LGL-enriched cell preparations were tested with the anti-lymphocyte monoclonal antibodies OKT6, anti-Leu1, anti-Leu2a, anti-Leu3a, and anti-human Lyt3, and also with OKM1 antibody. Significant reactivity was found with anti-Leu2a (59 +/- 8%), anti-Lyt3 (55 +/- 4%) and OKM1 (81 +/- 11%) antibodies, whereas T6, Leu1, and Leu3a antigens were less pronounced or missing on LGL. As a further approach, another monoclonal antibody, VEP13, which reacts with LGL, granulocytes but not monocytes and is therefore different in its specificity from OKM1 and OKT10, was used for identification of LGL. The coexpression of antigens as defined by the above-mentioned antibodies and OKT10 on VEP13+ cells was studied. Again, phenotypes similar to those observed on LGL enriched by Percoll gradient centrifugation were found: of VEP13+ cells 84 +/- 6% reacted with OKM1, 82 +/- 5% with OKT10, 52 +/- 17% with anti-human Lyt3, and 48 +/- 14% with anti-Leu2a, whereas VEP8, VEP9, VIM-D5, VIB-C5, T6, Leu1, Leu3a antigens were not expressed on VEP13+ cells. Taken together as an overall evaluation of phenotypic characteristics, our data indicate that LGL cannot be integrated into one of the known lymphocytic or myelomonocytic lineages. LGL show an intermediate phenotype depending possibly on varying differentiation or activation stages of haemopoietic cells. However, the possibility also exists that LGL belong to a separate, yet undefined cell lineage.

Antibodies, Monoclonal↗
PubMed1983

Target-effector-cell interactions in the human natural-killer(NK)-system: isolation of target structures.

The existence of structures on NK-sensitive target cells selectively recognized by the effector cells have been postulated. To test this hypothesis, four selected human cell lines were investigated for target-cell proteins which could serve as specific ligands for the putative NK-cell receptor(s). NP-40 extracts from two highly NK-sensitive (K 562 and Molt-4) and two rather insensitive cell lines (HL-60 and Reh-6) were fractionated on SDS-polyacrylamide gels and tested for their ability to inhibit binding of effector to target cells as well as NK cytotoxicity. Three fractions with molecular weights (MW) of 200, 120 and 80 +/- 10 KD isolated from K 562 cells were able to inhibit binding of large granular lymphocytes (LGL) to K 562. Of the other cell lines, Molt-4 and HL-60, both which were able to inhibit lysis of K 562 in a cold target inhibition assay, showed also two inhibitory fractions with MW 120 and 80 KD, whereas Reh-6, which is not able to compete with 51Cr-labelled K 562 in a cytotoxicity assay, lacked these structures. The 200, 120 and 80 KD fractions isolated from K 562 and the 120 and 80 KD fractions from Molt-4 and HL-60 were able to inhibit lysis of K 562 cells when added to the cytotoxicity assay. By adsorption/elution of radiolabelled K 562 extracts to/from LGL it was possible to detect an 80 KD target-cell surface protein which became preferentially bound by LGL-enriched but not by LGL-depleted lymphocyte preparations. Our results indicate the existence of target-cell proteins in NK-sensitive cell lines which serve as specific ligands for binding of NK cells. These target-cell structures of human cell lines differed from NK target structures described for mouse-NK-sensitive cell lines.

Binding, Competitive↗
PubMed1983

A monoclonal antibody (VEP10) against an antigen shared by human large granular lymphocytes, thymocytes and activated T cells.

In an attempt to produce monoclonal antibodies against human large granular lymphocytes (LGL), the effector cells of natural killer (NK) and killer (K) activity, a monoclonal IgM antibody (VEP10) has been obtained. This antibody is reactive by indirect membrane immunofluorescence (IMF) with 14.7 +/- 8.5% peripheral blood lymphocytes (PBL), with greater than 95% thymocytes and with 25.0 +/- 5.0% bone marrow (BM) cells; a stronger expression of VEP10 antigen was found on thymocytes than on PBL and BM cells. Compared to unseparated lymphocytes a higher percentage (58.5 +/- 10.2) of VEP10+ cells could be detected in LGL-enriched cell preparations obtained by Percoll gradient centrifugation. Evidence that the VEP10 antigen is expressed on NK and K cells was provided by depletion of NK/K activity by antibody plus complement treatment of PBL. In addition, VEP10 antigen could be detected on certain human cell lines (Raji, Daudi, Molt4, Yurkat, KG1). The expression of VEP10 antigen on leucocytes could be increased by interferon-alpha treatment and was also observed on concanavalin A (Con A)- and phytohaemagglutinin (PHA)-activated cells. The IMF distribution of VEP10 antigen on various cell types and successful blocking experiments with OKT10 revealed that both antibodies seem to recognize the same or closely related epitopes on cell membranes. In addition to IMF, a more sensitive assay, rosette formation with VEP10-coated ox red blood cells, was employed to study VEP10 antigen expression on cells. Rosette formation experiments indicate that this antigen is also present although in lower amounts on IMF-negative cells, e.g. most T, B cells and monocytes. The finding that the expression of the VEP10 antigen increases under the influence of the thymic environment, mitogens or interferon suggests that VEP10 antibody recognizes a molecule involved in the proliferation and differentiation of haemopoietic cells.

Animals↗
PubMed1982

Immunoglobulin class and subclass distribution of dextran-reactive antibodies in human reactors and non reactors to clinical dextran.

The red cell-linked antigen-antiglobulin reaction (RCLAAR) with stearoyldextran-coated erythrocytes was used to characterize the immunoglobulin (Ig) classes and IgG subclasses of dextran reactive antibodies (DRA) in 27 dextran reactors (DR) and 96 on reactors (DNR). High titres of dextran reactive IgG were regularly found in sera of patients with severe dextran-induced anaphylactoid/anaphylactic reactions (DIAR) prior to the infusion. In four lethal cases IgG antibodies were found to be in the highest titre range of 16,384 to 32,768. In addition, high IgA and IgM titres were also in severe DIAR. DNR had much lower titres of dextran reactive antibodies of IgG, IgM and IgA classes and IgD antibody was absent in both groups. Dextran reactive IgE antibodies were not demonstrable in DR. Dextran reactive IgG2, IgG3, IgG4 and IgG1 (indirect measurement) were demonstrated in both DR and FNR. Dextran infusion caused variable neutralization in all Ig classes and IgG subclasses, but the contribution of IgG2 was considered most important because of its high titres and most pronounced neutralization in severe DIAR. It is concluded that DRA mainly of the IgG class, play a critical pathogenic role in the induction of severe DIAR, which accordingly is classified as immune complex (Type III) anaphylaxis. The method of RCLAAR allows to delineate a risk group of about 2% of potential reactors.

Adolescent↗
PubMed1982

A monoclonal antibody against a surface antigen shared by human large granular lymphocytes and granulocytes.

A monoclonal IgM antibody VEP13 was raised against a cell membrane antigen by immunizing BALB/c mice with a cell preparation enriched for human large granular lymphocytes (LGL). These cells are known to include the effector cells responsible for natural killer (NK) and killer (K) cell activity. By indirect immunofluorescence, VEP13 antibody reacted with 21.4 +/- 7.9% of peripheral blood lymphocytes (PBL) and more than 95% granulocytes but not with B lymphocytes, monocytes, erythrocytes, thrombocytes, thymocytes, and immature bone marrow cells. Cell suspensions enriched for T cells by means of E-rosetting using neuraminidase-treated sheep red blood cells contained 14.7 +/- 5.5% of VEP13+ cells. When PBL were treated with VEP13 antibody and complement, NK activity against a variety of target cells was greatly reduced and K cell activity was also strongly affected. Enrichment experiments of VEP13+ cells by means of the fluorescence-activated cell sorter revealed that all the NK activity resides in the VEP13+ fraction. This cell fraction was a homogeneous population of LGL. Studying the coexpression of various other antigens as defined by monoclonal antibodies, 84.6 +/- 4.6% of VEP13+ cells also expressed M1, 81.6 +/- 5.5% T10, 47.9 +/- 14.4% Leu 2a, 51.6 +/- 17.0% human Lyt-3, and 6.0 +/- 4.0% HLA-DR antigens. Leu 1, Leu 3a, and T6 antigens were found to be absent from VEP13+ cells. We conclude that VEP13 antibody should be helpful in determining LGL in peripheral blood as well as in tissue sections of tumor patients.

Antibodies, Monoclonal↗
PubMed1982

Antigenic heterogeneity of rat macrophages. A monoclonal antibody reacting only with alveolar but not with other types of macrophages.

Hybridoma antibodies were produced by fusing spleen cells from mice immunized with rat alveolar macrophages (AM) with P3 x 63Ag8/653 myeloma cells. Some of the hybridomas were processed to achieve monoclonality. Reactivity was tested in an indirect membrane immunofluorescence assay. One of the monoclonal antibodies, called VEP6 antibody, reacted with rat AM but not with peritoneal or splenic macrophages and not with peripheral blood monocytes of this species. It was also unreactive with cells from thymus, bone marrow, non-adherent spleen cells, granulocytes and erythrocytes, but it reacted with thrombocytes. Corynebacterium parvum activated AM were slightly less reactive then 'resident' AM, as determined in a fluorescence activated cell sorter. The VEP6 antigen was studied in polyacrylamide gel electrophoresis after immunoprecipitation from 125I-surface-labelled-macrophage NP40-lysates. Four specific radioactive bands were seen in the precipitates corresponding to molecular weights of 31, 33, 35 and 37,000. A slurred band was seen in this molecular weight range when immunoprecipitates of surface labelled thrombocytes were analysed. This study confirms the heterogeneity of macrophages by showing that certain antigens may be expressed only on a subpopulation of macrophages.

Absorption↗