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P Perlmann

Publications and source records attributed to P Perlmann.

At least 199 records · Page 11Linked to original sources
PubMed1982

Regulation of IgG-IgM interplay by antibody specificity in human K-cell-mediated cytotoxicity.

IgM antibodies, by themselves unable to induce human K-cell-mediated cytotoxicity, enhanced the lysis of TNP-coated bovine erythrocytes (TNP-Eb) induced by suboptimal concentrations of IgG antibodies. The antibodies used were directed against either TNP or intrinsic Eb antigens. The best enhancement of antibody-dependent cell-mediated cytotoxicity (ADCC) was obtained when IgG and IgM antibodies had different specificities. IgM antibodies with specificity similar to that of the IgG antibodies often inhibited rather than enhanced cytolysis. By using 125I-labelled anti-DNP IgG, the number of IgG/TNP-Eb was determined. Under the present conditions, at least 9000 IgG molecules/TNP-Eb were required for K-cell-mediated lysis in the absence of IgM. In the presence of IgM antibody concentrations optimal for enhancement of ADCC, the minimal number of IgG molecules required for induction of ADCC was 30-100 times lower. No enhancement of cytotoxicity was seen with more than the optimal concentration of IgM even when IgG binding to the target cells was not reduced by IgM. This suggested that induction of ADCC was dependent on contiguous IgG-Fc receptor interactions, which were inhibited owing to steric hindrance by excessive amounts of IgM in the critical contact areas between effector cells and target cells.

Animals↗
PubMed1982

Localization of T-lymphocyte areas in human lymphoid tissues by fluorochrome-labelled Helix pomatia A haemagglutinin.

Fluorochrome-labelled Helix pomatia A haemagglutinin (HP) stained T-dependent areas in cryostat tissue sections of human lymph node, tonsil, and spleen and thymocytes within thymic medulla but not within thymic cortex. Neuraminidase treatment of the tissue section was a prerequisite for the positive cell staining. The staining was cell-membrane-associated, and the histological pattern was essentially the same as that observed in parallel sections treated with monoclonal antibodies to T cells (OKT3, Leu-1). In addition, blood vessel walls and connective tissue were also stained by HP conjugates. The latter staining was independent of neuraminidase treatment, resistant to alpha-galactosidase treatment and was not blocked by pretreatment with anti-fibronectin antibody. Body types of staining reaction were specific inasmuch as unlabelled HP and the competitive sugar hapten N-acetyl-D-galactosamine blocked the reaction, Frozen, formalin-fixed tissue sections showed the same stainability and reaction pattern as unfixed sections.

Animals↗
PubMed1982

Transferrin receptors on mitogen-stimulated human thymus-derived lymphocytes.

The appearance of transferrin receptors on mitogen-stimulated human thymus-derived (T) lymphocytes was studied. When indirect immunofluorescence with immunoadsorbent-purified antitransferrin antibodies was used, approximately 10% of resting T cells were stained. This proportion increased to 50-80% of the cells 3-4 days after stimulation with the mitogenic lectins concanavalin A (Con A) and leucoagglutinin (La) from Phaseolus vulgaris. Almost all blast cells (greater than or equal to 90%) were positive. Cell binding experiments with 125I-labelled transferrin indicated the presence of 1-5 x 10(5) transferrin receptor molecules/cell with high avidity for transferrin (K = 2 - 12 x 10(8) l/mol). Analysis by sodium dodecyl sulphate polyacrylamide gel electrophoresis and autoradiography of cell lysates containing 125I-labelled T-cell surface components revealed two surface peptides (90 kdaltons and 80 kdaltons, reducing conditions), which selectively bound to insolubilized antitransferrin antibodies. The 90-kdalton peptide also bound to insolubilized transferrin. The 80-kdalton peptide is most probably transferrin and the 90-kdalton peptide the transferrin receptor. Unreduced transferrin receptor had a molecular weight of 180 kdalton. It is probably a glycoprotein, since it reacted with wheat germ agglutinin, La, and probably also Con A. The properties of the lymphocyte transferrin receptor are similar to those described for transferrin receptors on various in-vitro-grown transformed cells. This speaks in favour of a common receptor present on all proliferating human cells.

Concanavalin A↗
PubMed1981

Interaction of target cell-bound C3bi and C3d with human lymphocyte receptors. Enhancement of antibody-mediated cellular cytotoxicity.

The occurrence and distribution of distinct receptors for three C3 fragments on purified human blood lymphocytes were studied by rosette formation. Indicator cells were bovine, chicken, or sheep erythrocytes (E) bearing up to 100,000 molecules of human C3b (EC3b) without antibody. EC3b was converted to C3bi-bearing-E (EC3bi) with purified C3b inactivator (factor I) and beta1H (factor H), and to C3d-bearing E (EC3d) by treatment of EC3bi with trypsin. Using bovine E (Eb) as indicators, approximately 11% of the lymphocytes bound EbC3b, 6% bound EbC3bi and 2% bound EbC3d. Fractionation of the lymphocytes by adsorption to monolayers of C3-fragment-bearing Eb or by rosetting indicated that most of the cells with receptors for C3b were distinct from those having receptors for C3bi and/or C3d. Cells from two lymphoblastoid cell lines (Raji and Daudi) formed strong rosettes with EC3b, which were weak. 51Cr-labeled E was used as a target in antibody, C3-fragment-bearing E was not lysed by the lymphocytes. However, at suboptimal concentrations of IgG enhancing capacity of the fragments occurred in the order of C3bi greater than C3d greater than C3b. In addition, C3-fragment-bearing cells inhibited the lysis of antibody-coated cells not concluded that target cell bound C3 fragments enhance ADCC by improving contact between target cells and those effector cells which have C3 receptors. Cell-bound C3 effector cells. It is proposed that certain lymphocytes are capable of interacting with C3bi in addition to C3b and C3d and that C3bi and C3d have a greater regulatory effect on their cytolytic function than C3b.

Animals↗
PubMed1981

Tumour-associated antigens reacting with cytotoxic antibodies in serum of hepatoma-bearing rats.

3M-KCl extracts of the hepatoma D23 contain antigens that inhibit the complement-dependent cytotoxicity for D23 hepatoma cells of serum from D23 tumour-bearing rats (D23 TBS). Inhibition was not due to a general anticomplementary activity of the extracts. Although a minor part (25%) of the protein of D23-KCl extract was insoluble in PBS, this part contained most of the inhibitory activity. Fractionation of the PBS-soluble material of the extract on Concanavalin A-Sepharose showed that the inhibitory activity did not bind to the lectin. Analysis of D23-KCl extracts on a Sepharose CL-4B column showed that the antigens involved in the cytotoxicity were heterogeneously distributed in the high-mol. wt region (greater than 200,000). Precipitation with 10% trichloroacetic acid (TCA) of D23 KCl extracts revealed that most of the antigenicity was insoluble in TCA. Heating of D23 KCl extracts at 100 degrees C did not affect the antigenicity. Enzyme treatment of D23 extra nuclear membranes (D23 ENP) revealed that the inhibitory activity was not sensitive to proteolytic digestion, while treatment with phospholipase A2, C or D abrogated partly the inhibitory activity. The lipid nature of the antigenicity was indicated by its solubility in organic solvents as chloroform or n-butanol.

Animals↗
PubMed1981

Electrophoretic mobility of mouse T-cell hybrids.

The hybrid cell line BH2 was derived by fusion between an AKR thymoma BW5147 (HGPRT-) and C57BL thymoma EL-4R (TK-). The hybrid cells showed a near-tetraploid modal number of chromosomes, in contrast to the near-diploid stem-lines of both parental cell populations; most of the BH2 hybrid cells acquired marker chromosomes from both parental cell lines. Inoculation of the parental and hybrid cells into C57BL and AKR mice revealed that the possible admixture of revertant parental cells in the hybrid cell population was less than 10(-4). Anodic electrophoretic mobilities (AEM) of the mouse thymoma lines and their hybrids were compared with each other and with normal mouse lymphoid cells. The AEM of the parental and hybrid T-cell lines was slower than that of mouse T LNC and comparable with AEM of some thymocyte subsets. The mean AEM of parental and hybrid cell lines was 0.69 micrometers/sec/V/cm for BW5147 cells, 0.96 for EL-4R cells and 0.83 for BH2 cells, the mean AEM of the hybrid cell population being identical with the mean of the parental AEM values. The mean AEM was found to be a relatively stable characteristic of each cell line.

Animals↗
PubMed1981

Regulation of effector functions of human K-cells and monocytes by antigen density of the target cells.

Antibody-dependent cytolysis and phagocytosis mediated by human K-cells or monocytes against chicken erythrocytes (ChRBC) were studied. The antigen density of the target cells was varied by coating the cells with different amounts of 3H-labelled dinitrophenyl (DNP) hapten. The degree of antigenicity thus acquired by the target cells was assessed on the basis of their uptake of the isotope. Anti-DNP serum was used to induce lysis or phagocytosis. Below 500 antigenic determinants per ChRBC the target cells were not affected. However, at the density, lysis and/or phagocytosis was seen when the antibody concentration was high (2 X 10(-9) M). With less antibody present (2 X 10(-11) M) only monocyte-mediated phagocytosis was induced. The estimated lowest number of target-cell-bound antibodies required for K-cell-mediated lysis was approximately 50. The corresponding number for monocyte-mediated phagocytosis was approximately 20 IgG per ChRBC. The result suggests that interaction of several Fc receptors on the effector cells with IgG molecules bound to adjacent sites on the target cell membrane is an important factor in the regulation of these antibody-dependent cell-mediated effector functions.

Animals↗
PubMed1981

Regulation of IgG antibody-dependent cellular cytotoxicity in vitro by IgM antibodies.

IgM antibodies have previously been reported to either inhibit or induce antibody-dependent lymphocyte cytotoxicity (ADCC). Here we show that human lymphocytes lyse bovine erythrocytes (Eb) in the presence of either IgM of IgG anti-Eb from rabbits. Seven out of 20 IgM preparations (Sephadex G-200) were ADCC-active. IgG-dependent ADCC was inhibited by human IgG but not by IgM. In contrast, IgM ADCC was inhibited by both IgG and IgM. The effector cells in IgM ADCC were a subpopulation of lymphocytes with distinct Fc receptors for both IgG and IgM. Most of them also had sheep erythrocyte receptors. Extensive purification of the ADCC-active IgM antibody preparations indicated that very small amounts of contaminating IgG anti-Eb were responsible for ADCC induction. When purified and ADCC-inactive IgM antibodies were mixed with suboptimal concentrations of IgG antibodies, a strong enhancement of ADCC was found. To achieve enhancement, the two antibody isotypes had to be present on the surface of the same target cells, and the IgM effect was not due to the release of soluble ADCC-enhancing factors. Thus, in this system, IgM antibodies are not capable of inducing ADCC on their own. However, they enhance ADCC by improving the contactual interaction between target cells and a special subset of effector cells.

Animals↗
PubMed1980

Cytotoxicity in vitro of blood lymphocytes from bladder cancer patients and controls to allogeneic or autologous tumor cells derived from established cell lines or short-term cultures.

Blood lymphocytes from small groups of patients with transitional-cell carcinoma of the urinary bladder (TCC), clinical controls (CC) or healthy donors (HD) were tested for cytotoxicity in vitro by a 51Cr-release assay. The target cells were either from TCC or control tissue (long-term cultures) or were from short-term TCC cultures, kept in vitro for 10-20 transfer generations. When tested with allogeneic target cells from long-term cultures, TCC patients' lymphocytes tended to be more cytotoxic to TCC targets than to control targets. For the control lymphocytes this was not seen. A large proportion but not all of the cytotoxicity to these target cells was due to immunoglobulin-dependent cellular reactions, probably mediated by natural and disease-related antibodies of the lymphocyte donors, since it was significantly inhibited by Fab-fragments of rabbit antibodies to human immunoglobulin. Moreover, it was, to a large extent, mediated by lymphocytes with Fc-receptors for IgG. For seven of the TCC target cell cultures (two long-term and five short-term) autologous lymphocytes were also available for testing. While two patients were non-reactive to their own tumor cells, five reacted strongly in the autologous combinations. These autologous reactions were immunoglobulin-independent and were mediated by Fc-receptor-negative effector cells. In some instances, autologous cytotoxicity was accompanied by similar reactions to some of the allogeneic TCC targets but not to the allogeneic non-TCC control targets. On the basis of available information on HLA antigens in this material, the pattern of cross-reactions suggests that the cytotoxicity encountered in the autologous and in some of the allogeneic TCC-combinations may be the expression of antibody-independnet but specific CTL-mediated reactions, regulated by HLA. However, at the present stage of the investigation, other mechanisms must also be considered since the target cells from short-term TCC cultures were sometimes lysed by control lymphocytes in immunoglobulin-independent reactions. Whatever the explanation, the results show that the cytotoxicity observed in the in vitro systems is usually the net result of several different types of reaction. Which effector cell types and which mechanism of recognition will predominate in a given lymphocyte/target cell combination is greatly influenced by the nature and origin of the target cells used.

Aged↗
PubMed1980

Lymphocyte-mediated lysis of tumor cells in vitro (ADCC), induced by serum antibodies from patients with urinary bladder carcinoma or from controls.

IgG fractions from serum of patients with transitional-cell carcinoma of the urinary bladder (TCC), patients with carcinoma of the prostate (CC) and healthy donors (HD) were tested for their capacity to induce antibody-dependent lymphocyte-mediated cytotoxicity (ADCC) to tumor cells in vitro. Lymphocytes from healthy donors were selected for low natural cytotoxicity to the target cells from established cell lines of TCC or other origins. IgG was prepared by adsorption of serum to Sepharose-bound protein A from Staphylococcus aureus and subsequent acid elution. When tested against a panel of six different target cells, most individual IgG preparations from all three donor groups contained antibodies inducing ADCC to some of the target cells. When IgG preparations from II untreated TCC patients were studied for ADCC induction to the TCC target T24 and the colon carcinoma HT29, cytotoxicity to T24 was, on an average, significantly higher than that to HT29. For IgG preparations from 18 TCC patients, treated with radiotherapy, a similar difference was seen but was not statistically significant. IgG preparations from II patients with carcinoma of the prostate and from 12 healthy donors did not show this differences. Moreover, while individual IgG preparations from untreated TCC patients were, on the average, significantly more cytotoxic to T24 than those from either of the two control groups, no such differences were seen when HT29 was the target. On the contrary, IgG preparations from patients with prostatic carcinoma were significantly more cytotoxic to HT29 than those from healthy donors. The results suggest that TCC patients develop a disease-related humoral immune response, superimposed on a "natural" immunity to a variety of antigens on the target cells used. The nature of the antigens involved in these reactions remains to be established. However, the results are compatible with previous findings, in these patients, of a bladder-tumor-related cellular cytotoxicity, to a large extent caused by the patients' own antibodies.

Aged↗
PubMed1980

Membrane-associated antigens on tumor cells from transitional-cell carcinoma of the human urinary bladder. I. Immunological characterization by xenogeneic antisera.

An antiserum was raised in rabbits by immunization with a human tumor cell line, T-24, derived from transitional cell carcinoma (TCC) of the urinary bladder. The specificity of the IgG fraction was assessed by antibody-dependent cellular cytotoxicity (ADCC), using purified blood lymphocytes from healthy human donors as effector cells and seven human cell lines as target cells (T-24 and two additional TCC-lines, two normal urothelial lines, one colon carcinoma and one malignant melanoma). The IgG induced strong lysis of all seven target cell types. However, lysis of the five urothelial lines was significantly stronger than that of the control tumors. Conversely, antisera to either of the control tumors induced a significantly stronger lysis of the homologous tumors than of the urothelial cells. All antisera contained antibodies to fetal bovine serum but removal of these by absorption did not change the specificity of the ADCC reactions. When the anti T-24 serum was exhaustively absorbed with glutaraldehyde-fixed spleen homogenate, the cytotoxicity to the control tumor targets was abolished. Although absorption reduced the antibody titer of the IgG preparation, ADCC to the TCC targets remained at a high level. There was no difference in the degree of lysis of the three TCC targets. Lysis of the two target lines from normal urothelium was slightly lower than that of the tumor cells. The results indicate that the anti-TCC serum contained antibodies to one or several antigens shared by five urothelial cell lines but not by the control tumors. Whether or not it also contained antibodies to TCC-associated antigens remains to be established. The molecular basis for these findings will be given in the accompanying paper.

Animals↗
PubMed1980

Plasma membrane-associated antigens on tumor cells derived from transitional-cell carcinoma of the human urinary bladder. II. Identification at the molecular level of plasma membrane-associated antigens.

The surface proteins of seven human cell lines (three bladder carcinomas (TCC), two normal urothelial lines, one colon carcinoma, and one malignant melanoma) were labelled with 125I by the glucose oxidase-lactoperoxidase technique. Plasma membranes of the cells were isolated and analysed by sodium dodecyl sulphate electrophoresis (SDS-PAGE). When analysed under reducing conditions by staining with protein stain, approximately 45 distinct membrane polypeptides were detected in all membrane preparations. Although the banding patterns for all cell lines were very similar, a 23 K and a 110 K band were only seen in the five unrothelial lines. When the same gels were analysed by autoradiography, between 13 and 17 bands were detected for each of the cell lines. However, in this case, analysis revealed individual and stable banding profiles for each. One 180 K band and one 100 K band were only seen in the autoradiographs of the two normal lines but not in those of the tumor membranes. Analysis under non-reducing conditions gave similar results. The antigenicity of these surface components was analysed by incubating detergent extracts of surface-iodinated cells with IgG from a rabbit anti-TCC serum, absorbed with fetal bovine serum and bound to protein A (from Staphylococcus aureus) on a matrix of Sepharose 4B. Analysis of the eluates by autoradiography after SDS-PAGE under reducing conditions showed that many of the labelled polypeptides were antigenic and shared by all seven cell lines. Analysis of eluates from IgG preparations, exhaustively absorbed with human spleen, revealed the presence of at least one antigenic 110 K polypeptide confined to the membrane of the urothelial cells. Preparation of a rabbit antiserum to this 110 K component, isolated from one of the TCC-lines and tested by ADCC, indicated that this polypeptide constitutes an important surface antigen, present on urothelial cells of both TCC- and normal origin but absent from the colon carcinoma and malignant melanoma used for control.

Antibody Specificity↗
PubMed1980

The role of viral glycoproteins in mumps-virus-dependent lymphocyte-mediated cytotoxicity in vitro.

Human peripheral blood lymphocytes (PBL) from healthy donors express enhanced natural cytotoxicity to target cells after a brief exposure to mumps virus in vitro. We describe here experiments aiming at elucidating the mechanism of this virus-dependent cytotoxicity. Treatment with proteolytic enzymes resulted in virus particles depleted of one or both kinds of their glycoproteins spikes. Removal of both of these components frrom the virion abrogated their ability to enhance cytotoxicity. This virus-dependent cytotoxicity was significantly but not completely reduced when one of the spike glycoproteins (gp 75, HANA) was removed selectively. Similarly, nucleic-acid-free preparations of the spikes, obtained by detergent treatment of mumps virions, also elicited enhanced cytotoxicity. However, the activity of these preparations was lower than that of untreated virions. Further evidence for the importance of HANA was provided by the use of (F(ab')2 fragments of anti-HANA-specific rabbit antibodies. When these fragments were allowed to react with virus before addition of the virus to PBL, no augmentation of cytolysis was observed. Antibody fragments specific for the other spike protein (gp 61, F) failed to inhibit the virus-dependent enhancement of PBL-mediated cytotoxicity. However, anti-HANA and anti-F blocked this reaction when added directly to the mixture of virus-treated PBL and target cells. The results are compatible with the hypothesis that virus-dependent cytotoxicity requires HANA for anchoring the virus to PBL receptors (and perhaps to bring effector and target cells into closer contact), whereas F may be involved in subsequent events increasing effector cell function.

Antigens, Viral↗
PubMed1980

Mitogenic responsiveness of human T-lymphocyte subpopulations: regulation by suppressive Fc-receptor-bearing T cells and influence of fractionation procedures.

The proliferative response induced by leucoagglutinin (La) in different subpopulations of human T lymphocytes was studied. Subpopulations enriched in cells with either high- or low-avidity receptors for sheep erythrocytes (SRBC) (EH +, EL +) were prepared by sequential E-rosetting. In addition, T lymphocytes prepared by E-rosetting under optimal conditions (E + TOT) were fractionated on wheat germ agglutin (WGA)-Sepharose columns, rendering fractions enriched in lymphocytes with either low- or high-avidity receptors for WGA. The T lymphocytes were found to comprise at least three functionally distinct subpopulations, differing with respect to mitogen responsiveness. Cells characterized by high-avidity receptors for WGA and SRBC were highly responsive to La stimulation, regardless of the method used for purification. In contrast, cells with low-avidity receptors for WGA and probably also for SRBC but lacking Fc receptors for IgG responded only marginally but were conditioned to respond when subjected to E-rosetting under optimal conditions. This response was suppressed by lymphocytes with Fc receptors for IgG, which probably also had low-avidity receptors for WGA and SRBC. The lymphocytes with high-avidity receptors for WGA ans SRBC did not appear to be susceptible to suppression by Fc gamma + cells.

Cell Separation↗
PubMed1980

Proliferative and cytolytic reactivities of human lymphocytes fractionated on wheat germ agglutinin-Sepharose columns before or after alloactivation in mixed lymphocyte culture.

Human T-lymphocyte preparations from peripheral blood with either high- or low-avidity receptors for wheat germ agglutinin (WGA) were obtained by fractioned on WGA--Sepharose columns. Both fractions contained progenitors of alloreactive T cells, proliferating in mixed lymphocyte culture (MLC) and acting as effector cells in cell-mediated lympholysis (CML). Proliferation and CML activity of the two fractions were equal and similar to those of the unfractionated cells. However, when the lymphocytes were fractionated after 5 days' MLC, most of the proliferating and cytolytic cells were found in the lymphocyte fraction enriched in cells with high-avidity receptors for WGA. The reactivity of the fractions was correlated to their content of blast-transformed cells. The binding of MLC-activated lymphocytes to WGA was specific, since it was inhibited by the competitive hapten D-GlcNAc and no cells were retained on control columns charged with human serum albumin-Sepharose. B cells and monocytic cells were enriched in the fraction with low-avidity receptors for WGA. As indicated by experiments in which cells were mixed in different proportions, the low MLC-CML activity of the lymphocytes in the fraction with low-avidity WGA receptors was not caused by suppressor cells present in that fraction.

Agglutinins↗