Showing papers on "Cytotoxic T cell published in 1970"

Specific in vitro Cytotoxicity of Thymus-derived Lymphocytes sensitized to Alloantigens

Abstract: THE immune response to a specific antigen is characterized by the development of antibody-producing cells and of sensitized lymphocytes active in cell-mediated immunity. Although there is good evidence that antibody-producing cells are bone marrow-derived cells1–2, the role of thymus-derived cells is less well understood. Development of cell-mediated immunity is impaired in neonatally thymectomized animals3, and it is therefore likely that sensitized lymphocytes are thymus-derived cells. Spleen cell populations of mice immunized with allogeneic cells contain lymphocytes able to destroy in vitro appropriate target cells bearing the sensitizing alloantigens4–5. Earlier studies demonstrating the in vitro cytotoxic activity of sensitized thymus cells6 suggested that cytotoxic cells found in immune spleen cell populations were thymus-derived. As shown recently7–8 mouse thymus-derived cells in the peripheral lymphoid organs carry a surface marker, the θ alloantigen9, and are lysed when incubated in the presence of anti-θ serum and complement. This study was undertaken to test the effect of anti-θ serum on the cytotoxic activity of spleen cells sensitized to alloantigens. Its effect on alloantibody-producing cells present in the same spleen cell populations was tested in parallel.

Cellular and humoral immune responses to human urinary bladder carcinomas.

Abstract: Leukocytes from 17 of 19 patients with urinary bladder carcinomas were cytotoxic for autochthonous as well as allogeneic bladder carcinoma cells in vitro. The cells from all 11 individual bladder carcinomas studied were susceptible to this cytotoxic action of patients' leukocytes. In contrast, no cytotoxicity was observed when cells from unrelated tumours or various normal tissues were used as target cells. Purified blood lymphocytes from patients whose leukocytes were active, were also cytotoxic. Sera of 8 out of 13 patients with bladder carcinomas contained complement-dependent antibodies which were cytotoxic for autochthonous and allogeneic bladder tumour cells. When serum was taken from the same patient on different occasions over a period of 8 months cytotoxicity was found in some samples but not in others. Sera from 4 out of 9 patients exhibited a blocking activity, which completely abolished the cytotoxic effects of patients' leukocytes. The serum of one out of 9 patients contained antibodies which were not cytotoxic without leukocytes but which conferred a cytotoxic activity onto leukocytes from control subjects. This opsonizing antibody was complement-dependent and probably of IgM nature. The effect of hydrostatic pressure therapy on the immune state of the patients was followed by examination of the leukocytes from 16 patients with bladder carcinoma. Leukocytes from 10 patients were cytotoxic before as well as after the pressure treatment. Leukocytes from six patients did not react before the treatment while those from four became active after treatment. A more detailed study of three individual cases indicated that cytotoxicity of the leukocytes appeared after pressure treatment and was of relatively short duration (approximately 1 month). In one case, the development of cytotoxic antibodies was similar. The patient who had opsonizing antibodies had no cytotoxic antibodies. The opsonizing antibodies appeared when the cytotoxicity of the leukocytes decreased.

Studies of allograft immunity in mice. I. Induction, development and in vitro assay of cellular immunity.

Abstract: Cellular immunity induced by tumour allografts in inbred mice was studied with the help of an in vitro assay system measuring the cytotoxic effect of sensitized lymphocytes on 51Cr-labelled target cells. It is shown that lymphoid cells from spleen, lymph nodes and blood of the allograft recipients reach a peak of cytotoxic activity on days 10–11 after immunization. Incubated with labelled target cells at a ratio of 100:1, the sensitized lymphocytes caused the specific release of up to 70 per cent of the radioactivity within 1 hour. A second population of target cells added to the same cell suspension was destroyed at a slightly accelerated rate, suggesting stimulation of the effector cells by the first interaction. The cytotoxic activity of circulating lymphocytes was found to reach a plateau between days 20 and 60 after immunization, while the activity of spleen cells dropped to low levels in the same time period. The specificity of target cell destruction by sensitized lymphocytes is demonstrated by the lack of lytic activity for syngeneic target cells, and by the selective destruction of target cells carrying a tumour specific antigen. Tumour cells, lymphocytes and embryonic fibroblasts of the donor strain are shown to differ considerably in their sensitivity to lysis by immune lymphocytes.

In vitro Cytotoxic Activity of Thymus Cells sensitized to Alloantigens

Abstract: THE thymus plays an important part in the development of certain immune reactions. Neonatally thymectomized mice showed an impaired antibody response to heterologous erythrocytes and serum proteins1. Recent studies, have demonstrated that collaboration between thymus-derived cells and bone marrow-derived cells was essential for mice to respond to sheep red blood cells (SRBC) by producing haemolysin-forming cells2–4. Thymus-derived cells, although undergoing mitosis in response to the antigenic stimulus5, did not produce antibody6, but influenced bone marrow-derived precursor cells to differentiate into antibody-producing cells4.

G (Gross) and H-2 Cell-Surface Antigens: Location on Gross Leukemia Cells by Electron Microscopy with Visually Labeled Antibody

Abstract: The hybrid-antibody method of locating cell-surface antigens in electron micrographs, with either ferritin or southern bean mosaic virus as the visual marker, was applied to the cells of a transplanted murine leukemia induced by Gross virus. The two antigens studied were (a) G (Gross) cell-surface antigen, which is a specific component of cells infected with Gross virus and is identified by cytotoxic hyperimmune C57BL/6 antiserum, and (b) H-2 antigen, which is the major histocompatibility determinant of the mouse. Both antigens were represented on the cell surface in discrete circumscribed areas. Neither antigen was present on free Gross virions or on virions in the process of budding from the cell surface. Thus G cell-surface antigen identified by C57BL mouse cytotoxic antiserum is not a constituent of the viral envelope, which accounts for the poor virus-neutralizing capacity of such antibody. Virus maturation may take place preferentially at regions of the cell surface where H-2 and G antigens are absent, for budding was seldom seen in H-2+ sectors and never convincingly in G+ sectors. In other experiments, serum from an untreated NZB mice aged 16 months gave labeling of the virion only, showing that this mouse strain, in contrast to C57BL and other strains, forms antibody to envelope antigen of Gross virus.

Studies of allograft immunity in mice: II. Mechanism of target cell inactivation in vitro by sensitized lymphocytes

Abstract: The mechanisms of the in vitro interaction of sensitized lymphocytes and allogeneic target cells has been studied in a tumour allograft system in inbred mice The cytotoxic effect of sensitized lymphocytes is shown to require the presence of Ca+ + and Mg+ + Pretreatment of the lymphocytes with trypsin led to inhibition of cytotoxicity, followed by spontaneous reversal after 1–3 hours incubation Reactivation was found to be blocked by an inhibitor of protein synthesis (cycloheximide) Cortisone was not found to inhibit the lytic interaction significantly; an occasional effect is thought to be due to toxicity of cortisone for lymphocytes as revealed by dye exclusion test Inhibition of DNA-synthesis with FUdR (an inhibitor of the enzyme thymidine synthetase) did not reduce the lytic activity of sensitized lymphocytes Isologous anti-target cell sera induced in various strains of inbred mice were found to be ineffective in blocking the cellular immune reaction in vitro when directed against a minor part of the antigenic complex, but strongly inhibitory when reactive against a major part or the whole complex Similarly, target cells lacking several of the sensitizing H-2 antigens were not lysed An isologous anti-lymphocytic serum induced in the graft donor strain and directed against the recipient strain (lymphocyte donor) did not inhibit the cytotoxic reaction In a heterologous system on the other hand, the lytic effect of guinea-pig lymphocytes sensitized against mouse target cells was effectively blocked by an anti-lymphocytic serum induced in mice of the graft donor strain by injection of recipient (guinea-pig) spleen cells

Age Responses of Cultured Mammalian Cells to Cytotoxic Drugs

Abstract: Summary A number of cytotoxic drugs (mitotic poisons, chemical mutagens, bifunctional alkylating agents, inhibitors of DNA, RNA, or protein synthesis, for a total of 18 agents) have been tested for differences in their lethal effects through the generation cycle of HeLa and Chinese hamster cells in culture. The patterns of age response of cells to each group of agents show some features in common: mitotic poisons, chemical mutagens, and inhibitors of DNA synthesis appear to be most effective on cells in S phase, alkylating agents in M and G 1 , and inhibitors of protein synthesis at the G 1 /S transition, whereas inhibitors of RNA synthesis elicit an X-ray-like age response, i.e. , show grestest activity on cells in M and at the G 1 /S transition. Further differences in lethal action have been defined by microscopic observations of the treated cells; these permit additional distinctions to be made between groups of agents. In the case of asynchronous cell populations, all the agents but 3 give rise to sigmoidal concentration-survival curves (an initial shoulder followed by an exponential decline). The exceptions are nitrogen mustard, which elicits an exponential curve, and hydroxyurea and pederine, which give rise to exponential curves followed by a plateau at about 45% survival level.

Relationship Between Growth Rate, Cell Volume, Cell Cycle Kinetics, and Antigenic Properties of Cultured Murine Lymphoma Cells

Abstract: The expression of H-2 and Moloney leukemia virus (MLV)-determined surface antigens of MLV-induced mouse lymphoma cells (YCAB) was studied during growth in vitro by indirect membrane immunofluorescence and complement-dependent, antibody-mediated cytotoxic sensitivity. In a growing cell population, the degree of antigenic expression was inversely related to the growth rate and cell volume. These findings suggest that the antigenic properties of YCAB cells are maximally expressed during the early interphase, presumably a part of the G1 period, and that the fast-growing cells pass relatively quickly through G1. The life cycle analysis of the same cells at varying intervals during the growth cycle revealed that the prolongation of population doubling time was mainly due to an extension of the G1 period, whereas the duration of S, G2, and mitosis was much less affected. The cell volume per se did not appreciably influence the expression of surface antigens. Populations of large cells were more rapidly growing, since they were in the late stage of their cycle.

Microcytotoxicity Test: Detection in Sarcoma Patients of Antibody Cytotoxic to Human Sarcoma Cells

Abstract: A microcytotoxicity test has been used to detect a factor cytotoxic for human sarcoma cells; the factor was found in serums from 70 percent of sarcoma patients, 58 percent of their family members, and 8 percent of serums from normal blood donors. This cytotoxin is an antibody against a common cell surface sarcoma antigen since it is specific for sarcoma cells, is complement dependent, and is extractable with the globulin fraction of serum.

Cell Interaction in an Immune Response in vitro: Requirement for Theta-Carrying Cells

Abstract: Cytotoxic antiserum to theta antigen reduces the capacity of mouse spleen cells to generate direct and indirect plaque-forming cells to sheep erythrocytes in vitro but does not affect plaque-forming cells, their precursors, or hemopoietic stem cells. The response of spleen cells treated with antiserum to theta antigen is restored by thymus cells incubated in vivo with sheep erythrocytes.

Anti-theta antibodies for detecting thymus-dependent lymphocytes in the immune response of mice to SRBC.

Abstract: MOUSE thymus cells possess a high concentration of the theta (θ)1 and Ly2 antigens Several approaches have demonstrated that the sensitivity of peripheral muriiie lymphocytes to the cytotoxic effect of θ and Ly antibodies is a thymus-dependent property The population of cells sensitive to the cytotoxic effect of θ antibodies disappears from lymph nodes3 and spleen4 after neonatal thymectomy Similarly, following neonatal thymectomy, the population of cells sensitive to Ly antibodies disappears from lymph nodes (unpublished results of M S and Yron) Following administration of heterologous anti-lymphocyte serum, a procedure resulting in elimination of thymus-dependent lymphocytes5,6, cells sensitive to θ antibodies disappear transiently from the lymph nodes7 and spleen4

The occurrence of two types of cytotoxic lymphoid cells in mice immunised with allogeneic tumour cells.

Abstract: Summary: Spleen cells from C57BL mice immunised once with L5178Y lymphoma cells, which are of DBA/2 genotype, were assayed for cytotoxicity by measuring their effect on the growth of L5178Y cells in vitro. Two populations of cytotoxic spleen cells were distinguished: (1) those found predominantly 6-12 days following immunisation; and (2) those found 14 days and later following immunisation. The cytotoxic activity of the “early” cells was relatively radioresistant and was not affected by drugs which inhibit nucleic acid synthesis. These early cells resemble those found in lymph from draining nodes, which are cytotoxic only 4-8 days after immunisation. Spleen cells taken from mice and rats 21 days after immunisation lost cytotoxic activity by exposure to 500 R of X-rays and to Mitomycin C, actinomycin D, and potassium cyanide. Removal of macrophages did not reduce the cytotoxicity of either class of spleen cell. Cytotoxicity was unaffected by the addition of a source of complement, but this does not exclude the participation of some complement components (which are synthesised by spleen cells). By following the release of 61Cr, it was shown that the L5178Y cells lysed sooner after the addition of spleen cells taken at 7 days, as compared to 21 days, after immunisation. The 21-day spleen cells acquired some of the properties of 7-day spleen cells (such as radioresistance) after exposure to target cells for 10 hr. The hypothesis is advanced that the cells responsible for cytotoxicity in spleens at 7 days after immunisation are immunoblasts (i.e., large pyroninophilic cells), as had earlier been shown to be the case for cells in the lymph from immunised donors. These cells, it is postulated, are directly cytotoxic, possibly because they already possess the machinery for the synthesis of antibody. The cells found in spleen 21 days after immunisation are only potentially cytotoxic and become transformed—hence their radiosensitivity—by contact with target cell antigen into the actual cytotoxic cells, which are presumably immunoblasts

Serologic Demonstration of a Thymus-Dependent Population of Lymph-Node Cells

Abstract: The aim of the present study was to determine whether the sensitivity of murine lymph-node cells to isoantibodies against the ϑ and Ly-antigens depends on the presence of the thymus. Neonatal and adult mice of various strains were thymectomized and their lymph-node cells tested at various intervals after thymectomy. Following either neonatal or adult thymectomy, the lymph-node cells of RIII/Jem mice lost their sensitivity to the cytotoxic effect of ϑ-AKR antibodies. The lymph-node cells of neonatally thymectomized C57BL/6 mice became refractory to the cytotoxic effect of ϑ-C 3 H antibodies, whereas the cells of neonatally thymectomized DBA/1 mice became refractory to ϑ-C 3 H and Ly-antibodies. In C 3 H/An mice, neonatal thymectomy resulted in an almost complete loss of the sensitivity of lymph-node cells to ϑ-C 3 H and Ly-antibodies. Some neonatally thymectomized RIII mice were grafted with allogeneic thymuses, and their lymph nodes were examined 2 to 3 weeks later. The lymph nodes of such reconstituted animals contained cells displaying the ϑ isoantigenicity distinctive for the thymic graft. In addition, these lymph nodes contained a slightly greater number of host cells sensitive to ϑ antibodies than did the lymph nodes of thymectomized littermates which did not receive thymus grafts. These results indicate that the lymph-node cells which are sensitive to the cytotoxic effect of ϑ and Ly-isoantibodies are thymus-dependent, and that at least some of them are thymus-derived. Moreover, the thymus may possibly affect the expression of the ϑ and Ly-antigens in lymph-node cells by an indirect control mechanism.

Antigenic Study of Unfertilized Mouse Eggs: Cross Reactivity with SV40-Induced Antigens

Abstract: Serum obtained from guinea pigs immunized with unfertilized C57BL/6 mouse eggs was found to be cytotoxic in the presence of complement for eggs obtained from syngeneic and allogeneic mice. The anti-egg serum was not cytotoxic for rat eggs, lymph node cells, methylcholanthrene-induced tumor cells, or 3T3 cells obtained either from syngeneic or allogeneic mice. The anti-egg serum was, however, cytotoxic for SV40-transformed 3T3 cells and C57BL/6 cells. After absorption with SV40-transformed cells, anti-egg serum lost its cytotoxicity for mouse eggs.

The role of immunoglobulins in lymphocyte-mediated cell damage, in vitro. II. The mechanism of target cell damage by lymphoid cells from immunized rats.

Abstract: Lymph node cells from Black Hooded (BH) rats immunized with Freund's complete adjuvant (CFA) are only poorly cytotoxic to target cells treated with target cell specific antibody. Normal spleen cells are highly cytotoxic to antibody coated target cells. When 106 lymph node cells, from rats immunized with Chang cells in CFA, are mixed with 107 spleen cells from unimmunized rats, the mixture is 8.6 times more cytotoxic than the sum of the cytotoxicities of the two lymphoid cell populations alone. Immune lymph node cells were no more cytotoxic in the presence of 5 per cent fresh guinea-pig serum than in the presence of heat inactivated guinea-pig serum. Immune spleen cells are prevented from damaging target cells by antagonists of protein synthesis such as Puromycin. Puromycin, however, does not alter the cytotoxic effect of either immune or non-immune spleen cells on antibody coated target cells. From these experiments it is tentatively suggested that lymphoid cells from immunized animals mediate target cell damage by a reaction involving firstly immunologically specific responder cells which synthesise antibody and secondly non-specific effector cells which damage the antibody coated target cells. Evidence is presented which suggests that stable soluble factors may not be responsible for mediating target cell damage in this system.

Failure of certain cytotoxic lymphocytes to respond mitotically to phytohaemagglutinin.

Abstract: CYTOTOXIC activity by lymphocytes has attracted considerable interest because of its possible role in the rejection of grafted tissues and neoplastic cells. Damage to target cell caused by lymphoid cells was first demonstrated in 1960 by Govaerts1, and there were several subsequent reports of immunologically specific cytotoxicity towards target cells by lymphoid cells from sensitized donors. These have recently been reviewed extensively2. The situation was complicated when cytotoxic activity by lymphocytes from apparently unsensitized donors was demonstrated in 1964 by Holm et al.3, in cultures of lymphoid cells and target cells when phytohaemagglutmin (PHA) was incorporated into the medium. Holm and Perlmann5 later showed that several other circumstances could lead to immunologically non-specific cytotoxic activity by lymphocytes. The induction of cytotoxicity in all these systems seemed to correlate well with increased mitogenic activity in the lymphocyte population tested. Recently it has been shown that immunologically nonspecific cytotoxic activity can be evoked from lymphocytes when the target cell antigens are complexed with certain antibody5–7. This effect has been demonstrated in a wide variety of species including man8, and does not seem to require the participation of complement components. We have previously reported that much of the immunologically specific target cell damage by lymphocytes in rats is dependent on immunoglobulin sensitization of target cells9. The sensitizing antibody, in this case, is synthesized by lymphocytes which are not themselves cytotoxic. Bubenik, Perlmann and Hasek10 have provided evidence that this mechanism brings about homograft rejection in donors made tolerant to graft antigens. Although there has been no report of antibody-induced cytotoxicity being associated with blast transformation, transformation in response to antigen-antibody complexes has been described11,12.

On the reactions of human synovial cells exposed to homologous leucocytes in vitro.

Abstract: Human synovial cells were exposed in culture to leucocytes from unrelated donors and to hyaluronidase, separately and together. Polymorphonuclear leucocytes rapidly lowered pH and severely damaged the synovial cells. Lymphocytes carefully freed from PMN-stimulated synovial cell growth or, at the worst, depressed it slightly. Hyaluronidase alone tended to stimulate cell growth whereas lymphocytes and hyaluronidase together were often cytotoxic after latent periods of 48–72 hr. The stimulating and inhibitory effects of lymphocytes upon synovial cells depended on the ratios and on the particular pairings of the two cell types. Lymphocytes did not show blast transformation during the cytotoxic reactions. The inhibitory effects of lymphocytes combined with hyaluronidase were partially blocked by small amounts of heparin, and completely blocked by hydrocortisone. It is suggested that the potentiating action of hyaluronidase is attributable to removal of pericellular gels which thus allows the close contact necessary for cytotoxic effects of lymphocytes. Cytotoxic reactions between lymphocytes and synovial cells were incidentally found to be associated with increased glucose consumption.

HL-A Antigens from a Continuous Lymphoid Cell Line Derived from a Normal Donor: I. Solubilization and Serologic Characterization

Abstract: Water soluble HL-A antigens isolated from a cultured human lymphocyte cell line derived from the peripheral blood of a normal donor inhibited cytotoxic reactions of monospecific anti-HL-A antisera in a pattern identical to that found upon direct and absorption typing of the donor's peripheral lymphocytes. The possibility of obtaining large quantities of cells from mass cultures now makes the chemical and biologic characterization of HL-A antigens a reality.

Antigenic Expression of a Murine Lymphoma during Growth in vitro

Abstract: WHILE studying a Moloney virus (MV) induced lymphoma in culture, we were puzzled by the disappearance of the antibody-mediated cytotoxic sensitivity of the cells several days after explantation. After a longer time in culture, however, these cells regained sensitivity to the same sera with complement. The experiments have been repeated in better controlled conditions, and some of the results obtained are reported here.

Effect of cell surface antigen density on immunological enhancement.

Abstract: The density of antigens on the surface of allograft target cells seems to determine whether IgG antibody manifests predominantly its cytotoxic action or whether immunologicol enhancement can operate.

Antitumour effect of lymphoid cells activated by interferon.

Abstract: INTERFERON induces a cytotoxic effect in normal mouse spleen cells against allogeneic tumour target cells in tissue culture1,2. We here present evidence that syngeneic lymphoid cells may be similarly activated by interferon and that syngeneic lymphoid cells plus interferon suppress the growth of tumour cells in vivo.

Antigenic Analysis of L Strain Cells: A New Murine Leukemia-associated Antigen, “L”

Abstract: Summary Analysis of a normal tissue culture cell line (L strain) by serological methods and by induction of transplantation immunity revealed three antigens associated with murine leukemias present in these nonleukemic cells: ( a ) the group-specific antigen of murine leukemia viruses; ( b ) an antigen common to Friend, Moloney, Rauscher, and Graffi leukemias (FMRGi) The group-specific and FMRGi antigens are probably related to the nonleukemogenic type C virus present in L cells The nature of this agent is briefly discussed; ( c ) a new antigen which is also present in various virus-induced leukemias of several strains and in the dimethylbenzanthracene-induced EL4 leukemia It was called L antigen L antigen was shown to be different from other already described murine leukemia antigens No tumor rejection of L + tumors was observed in hyperimmune mice despite the presence of cytotoxic antibodies in the blood Enhancement of tumor growth was frequently observed in this situation The origin of L antigen and its role in tumor immunity are briefly discussed

E Antigen: A Cell-Surface Antigen of C57BL Leukemias

Abstract: SUMMARY Antisera were prepared in (C3H/An X !)F! mice against a transplanted leukemia (E9SL2) that had arisen spontaneously in C57BL/6 mice. After removal of cytotoxic antibodies to normal alloantigens by absorption in vivo in C57BL/6 mice, the antisera detected an antigen, designated E, which is distinct from the four previously recognized cell-surface antigens (G, FMR, TL, and ML) associated with mouse leukemias. E antigen was detected on two other spontaneous leukemias of C57BL/6 origin and on the long-transplanted chemically induced leukemia, EL4. It was not found on any normal C57BL/6 tissues nor on radiation-induced or on virus-induced (Gross, Moloney, Rauscher) C57BL/6 leukemias. Thirty-nine solid tumors and leukemias from strains other than C57BL/6 lack E antigen. By the indirect immunoferritin technique, E antigen was seen to occupy discrete patches on the surface of E+ leukemia cells. Murine leukemia virus (type C or enveloped A) was not observed in E+ leukemias. Intracisternal A particles were present, but, as these are found also in E—leukemias and solid tumors, it is unlikely that they are related to E antigen. Thus, the origin of E antigen, whether from cellular genes or from viral genes, is unknown.

Reduction of colony-forming cell sensitivity to arabinosylcytosine by halothane anesthesia.

Abstract: Light anesthesia for 24 hr with either halothane or nitrous oxide significantly reduced the destruction of normal murine hematopoietic stem cells by arabinosylcytosine, as judged by results with the spleen colony-forming unit assay. Neither anesthetic affected the extent of reduction of lymphoma colony-forming units by arabinosylcytosine. Halothane, in combination with vinblastine, similarly protected normal hematopoietic cells but not lymphoma cells. Halothane alone had no significant effect on either normal or lymphoma colony-forming cells, whereas nitrous oxide by itself reduced lymphoma colony-forming cells to 9% of the number found in control mice. Since protection of normal cells was seen with combinations of different anesthetics and different phase-specific chemotherapeutic agents, these results may indicate a general phenomenon whereby anesthetics increase the selectivity of cytotoxic drugs by protecting normal cells against them.