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Biomedical subjects

S Thierfelder

Publications and source records attributed to S Thierfelder.

At least 109 records · Page 6Linked to original sources
PubMed1983

Analysis with monoclonal antibodies of human lymphoid cells forming rosettes with rabbit red blood cells.

Rabbit red blood cells have previously been shown to rosette with a subpopulation of thymocytes and with mitogen activated peripheral lymphocytes but not with unstimulated lymphocytes. Using monoclonal antibodies and double marker assays we studied the phenotype of these cells. In thymus, over 90% of rosetting cells express antigens of immature thymocytes (HTA1, OKT6). A proportion of the rosetting cells shows in addition antigens of mature thymocytes (OKT3, UCHT1). These cells probably correspond to a stage of intrathymic maturation between common and mature thymocytes. Virtually all rosetting cells are T cells and express an antigen related to T cell activation (TAC) when lymphocytes are activated by mitogens like PHA or Con A. Few rosetting cells are Ia positive. Two other antigens (OKT9, OKT10) known to be associated with proliferating and immature cells, are found in variable proportions on rosetting cells. After stimulation with allogeneic lymphocytes, fewer rosettes are detected than after stimulation by mitogens. Cells activated by a soluble antigen (PPD) and forming rosettes with rabbit red blood cells have a helper phenotype (Leu3a positive). Screening of leukaemia cell samples revealed that only cells from patients with T-ALL form rosettes with rabbit red blood cells. Rosette formation is almost totally inhibited by a polyclonal anti-thymocyte serum and two monoclonal antibodies (OKT11A,Lyt3) which have been shown to block rosettes with sheep erythrocytes.

Animals↗
PubMed1982

Auer-rod positive myelocytic leukemia cells in diffusion chambers: differentiation along the eosinophilic pathway.

Auer-rod positive acute myelocytic leukemia (AML) blasts from a 33-year-old patient were cultured in diffusion chambers (DC) in order to test their differentiation potential. The cells were labeled with anti-human granulocyte anti-serum known to be negative for eosinophils, and evaluated using the unlabeled peroxidase-antiperoxidase (PAP) method. Parallel to a decline in the number of leukemic blasts there was an increase of up to 86% in the number of granulocytic cells belonging to the eosinophilic series. Auer-rod bodies were found in the eosinophilic cells even after 20 days in culture. Staining with anti-granulocyte antiserum failed to demonstrate positive cells at any time during DC culture. Based on the negative reaction with the anti-granulocytic antibodies already at an early stage of development evidence is provided for the existence of a progenitor cell exclusively committed to the eosinophilic pathway.

Adult↗
PubMed1982

Comparison of currently available monoclonal antibodies with conventional markers for phenotyping of one hundred acute leukemias.

One hundred acute leukemia cell samples (89 ALL, 11 AMML) derived from children's bone marrow at diagnosis were typed for the reaction with 15 monoclonal antibodies (mAbs). Subdivision in ALL-subgroups was performed according to conventional markers. Only some mAbs like VIL-Al which is directed against the cALL-antigen, can substitute polyclonal rabbit antisera. Additional subclassifications became evident by the use of mAbs for T-cell differentiated ALL forms. However, unexpected negative reactions must be taken into account as observed for all T-directed mAbs with individual T-cell ALL samples.

Acute Disease↗
PubMed1982

Monoclonal antibodies against T-cell antigens studied by immunohistochemistry.

Fifteen monoclonal antibodies against different T-cell antigens were studied by immunohistochemistry in thymus, fetal thymus, fetal liver, palatine tonsils, and a few T-cell lymphomas. OKT 9 was identified as reacting with hemopoietic stem or precursor cells in fetal liver as well as with early B-determined lymphocytes in tonsillar germinal centres. OKT 10 labelled lymphocytes in thymus and surprisingly also the cytoplasm of some tonsillar cells with plasma-cell like appearance. OKT 6 and MAS 036 b reacted only with thymic cells. OKT 4, OKT 5, OKT 8,8-11, labelled thymic cells- and portions of interfollicular cells in tonsils. OKT 3, NEI 016, NEI 015, and T 28 stained a majority of thymic cells and of tonsillar interfollicular lymphocytes. IFH-M 203, NEI 012 and 4-11 were positive with the majority of T-lymphocytes in tonsils but labelled only a few thymic cells.

Animals↗
PubMed1982

Anatomical distribution of call antigen expressing cells in normal lymphatic tissue and in lymphomas.

Anatomical distribution of common acute lymphoblastic leukemia antigen (CALLA) was studied in lymphomas as well as in normal lymphatic organs using the monoclonal antibody VIL-A1. Twelve lymphomas were labelled by VIL-A1. Three of the 12 tumours also had T-cell marker, six lymphomas also showed immunoglobulin staining and only three tumours were pure CALLA lymphomas. Tonsils showed a distinct CALLA labelling of many germinal centre cells and of singular cells in interfollicular T-cell regions. Children's thymuses showed rare distinctly labelled cells in the cortex and medulla and slightly more cortical cells stained faintly by VIL-A1. Foetal thymuses of about the twelfth week of gestation contained many heavily labelled cells. The findings are discussed as evidence for the presence of CALLA on immature B as well as T lymphocytes. They favour the idea of CALLA as a common lymphocyte differentiation antigen although other possibilities of interpretation are also discussed.

Antigens, Neoplasm↗
PubMed1982

Characterization of autologous rosette-forming cells with a series of monoclonal antibodies.

The phenomenon of autorosette formation was investigated by incubating the peripheral blood mononuclear cells of 5 normal persons with a series of monoclonal antibodies and an FITC-labelled second layer before allowing them to bind to autologous red blood cells. The antibodies used were OKT3, OKT4, OKT5, OKM1 and OKIa1, defining mature T cells, the inducer and suppressor subsets of T cells, monocytes and Ia antigen bearing cells, respectively. By this procedure the percentage of autorosette-forming cells was only slightly decreased. With this double marker analysis, the percentage of fluorescent cells among cells forming autologous rosettes was approximately the same as in the total mononuclear cell population before rosetting. In conclusion we could demonstrate that autologous rosettes in man may be formed by T and probably B lymphocytes as well as by monocytes and that there is no preference for the inducer and suppressor subsets of T lymphocytes.

Antibodies, Monoclonal↗
PubMed1981

Immunohistochemical identification of T- and B-lymphocytes delineated by the unlabelled antibody enzyme method. III. Topographical and quantitative distribution of T- and B-cells in human palatine tonsils.

T-lymphocytes and B-lymphocytes are identified in tissue sections of human tonsils by applying the unlabelled antibody enzyme method. The epithelium of the tonsils contains a majority of immunoglobulin-positive cells and fewer T-lymphocytes. In the subepithelial zones, areas composed of B-cells predominate, however, regions containing T-lymphocytes are also present. The latter are mainly arranged in the lamina propria around high-endothelial venules and often include plasma cells containing immunoglobulin. Follicles containing germinal centres display a complex structure which changes during development. The lymphocytic cap consists of densely packed lymphocytes, labelled heavily by anti-IgM and anti-IGD, and of individual T-lymphocytes. Germinal centres show a framework of immunoglobulin-positive dendritic reticular cells; they contain some heavily labelled lymphoid cells and several cells weakly labelled by anti-IgM and anti-IgA, as well as a small number of T-lymphocytes. Furthermore, the total areas of T- and B-lymphocytes measured by planimetry may differ considerably between different tonsils. Especially total areas of germinal centres vary to a great extent. The quantitative data on amounts of T- and B-cells achieved by planimetry are comparable to those reported in cellular suspensions of tonsils.

B-Lymphocytes↗
PubMed1981

[Bone marrow transplantation in acute leukemias: antibody treatment for suppression of graft-versus-host disease (author's transl)].

Anti-human-thymocyte globulin (AHTZG) was applied to prevent GvHD in clinical bone marrow transplantation. AHTZG produced by absorption with several cell preparations reacted specifically with T-lymphocyte populations and was no longer inhibitory to human CFUc and bone marrow growth in diffusion chambers. Marrow grafts of 14 patients with ALL were incubated in vitro with AHTZG and transferred to the recipients conditioned with antileukemic chemotherapy and total body irradiation of 1000 rad. Ten patients were transplanted after relapse, four patients during remission. The patients tolerated the marrow without side effects and a hemopoietic engraftment was seen in 12 cases. Three patients showed signs of GvHD on the skin, two of them showed later on also manifestations in the liver. In the other cases no GvHD could be detected. Five out of 14 patients are still alive between 144 and 964 days post transplantation in remission.

Acute Disease↗
PubMed1981

Suppressive activity of cell-free ascites obtained from murine tumors. Soluble Fc receptor as a possible active agent.

It has been shown that cell-free ascites (CFA) from Ehrlich carcinoma, AKR leukemia, and CBA thymoma, which all had strong suppressive activity in vivo, inhibit EA-rosette formation, complement-dependent hemolysis, and agglutinate EA-complexes. Since these are the characteristics of soluble FcR the data suggest the presence of FcR in CFA tested. To test whether the suppressive activity observed in vivo was due to the soluble FcR and FcR-like fraction was absorbed out from CFA or Ehrlich carcinoma by means of antigen-antibody complexes. The isolated FcR-like fraction was strongly suppressive in vivo. Additional support for the proposition that soluble FcR might be one of the mediators of suppression in vivo was gained by testing cell-free supernatants (CFS) of cell-line cells known to shed off FcR into the medium. It could be shown that CFS of highly FcR positive K-562 cells inhibited PFC stronger than did the CFS of weakly FcR positive Raji cells.

Animals↗
PubMed1981

Tritium radiolabeling of antibodies to high specific activity with N-succinimidyl [2,3-3H] propionate: use in detecting monoclonal antibodies.

A simple method has been established for tritium labeling immunoglobulins. This label avoids certain disadvantages of 125iodine such as high radiation hazard and requirement for frequent labeling owing to the short half-life of this isotope. High specific activities (range 1.8-9.0 cpm/mu g protein) were obtained with no loss of functional activity as demonstrated by passive hemagglutination. The labeled conjugate is especially suitable for detection of activity in hybridoma supernatants by indirect binding assay. Adapted to microtiter plates, the method is suitable for large numbers of samples, e.g. up to 800 supernatants may be examined daily. The utility and advantages of the binding assay with respect to reproducibility, sensitivity, binding kinetics, easy and rapid performance are described.

Animals↗
PubMed1980

Immunological conditioning of bone marrow for autotransplantation in childhood acute lymphoblastic leukaemia.

Samples of bone marrow from 32 leukaemic children were removed during remission and stored in liquid nitrogen for retransplantation during relapse. Subsequently two children in advanced stages of common acute lymphoblastic leukaemia (cALL) were transplanted with their own cryopreserved marrow cells, after intensive combination chemotherapy and high doses of radiation therapy. Before grafting, the marrow cells were treated with purified heterologous antibodies prepared against cALL antigens, to remove any residual tumour cells. The antibodies showed high cytotoxic activity against leukaemic cells of cALL type without interfering with normal haemopoietic stem cells. Evidence of take was obtained in one patient, who died on day 7 with cardiac failure. In the other patient the dose of nucleated marrow cells grafted was 1.9 x 10(8)/kg (86 000 CFU-C/kg). The patient achieved complete haematological recovery on day 27 and a normal platelet count after day 50 and is now in complete remission. Marrow cells collected during remission and treated with antileukaemic antibodies can repopulate bone marrow after conditioning of the recipient with high doses of radiation.

Antibodies, Neoplasm↗
PubMed1980

T cell-mediated cytotoxic immune responsiveness of chimeric mice bearing a thymus graft fully allogeneic to the graft of lymphoid stem cells.

Fully allogeneic, chimeric mice were established by adult thymectomy of (A x B) F1 animals, grafting parental A-type thymus under the kidney capsula, followed by lethal (900 rd) irradiation and reconstitution with B parental-type bone marrow cells treated with xenogeneic anti-T cell antiserum plus complement. Following in vivo sensitization with inactivated Sendai virus (SV) suspensions, no virus-specific T cells could be detected within the spleen cells of the mice. Upon stimulation with third-party allogenic cells in a primary mixed lymphocyte culture, spleen cells of all animals generated alloreactive cytotoxic T lymphocytes (CLT). More interestingly, upon secondary in vitro stimulation with inactivated SV-conjugated B-type stimulator cells, B-type-restricted, virus-specific CTL were inducible in each case. Upon restimulation with SV-conjugated A-type stimulator cells, A being the H-2 type of the grafted thymus, T cells of some but no all mice generated A-type-restricted, virus-specific CTL. The data suggest that in allogeneic, chimeric mice virus-specific CTL can be induced. Moreover, virus-specific CTL, restricted to the H-2 type of the lymphoid stem cell inoculum, are more readily inducible than those restricted to the H-2 type of the allogeneic thymus.

Animals↗
PubMed1980

T cell mediated cytotoxic immune reactivity of bone marrow reconstituted chimeric mice.

The capacity of bone marrow reconstituted chimeric mice to mount sendai virus specific H-2 restricted as well as alloreactive cytotoxic T-cell responses has been investigated. Chimeras of the type a leads to (a x b)F1 and (a x b)F1 leads to a were used. In addition chimeras produced with (a x b)F1 mice grafted under the kidney capsula with a type parental thymus, thymectomised, lethally irradiated and reconstituted with either a, (a x b)F1 or b type bone marrow cells were tested. In agreement with the data of Zinkernagel and Bevan it was noted that virus specific T cells of semi-allogeneic chimeric mice are able to recognise virus antigens in the context of the MHC of the thymus in which they have maturated. The unexpected finding was that fully allogeneic chimeras were able to mount both alloreactive CTL and H-2 restricted, virus specific CTL. The H-2 restricted CTL detected were preferentially restricted to their own MHC type. In some animals also virus specific CTL restricted to the allogeneic thymus MHC type were observed. Data are also presented to indicate that longterm cultured bone marrow cells have the potential to repopulate lethally irradiated mice.

Animals↗