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1.
Summary We have previously shown that, as a consequence of low-dose melphalan (l-phenylalanine mustard) treatment, thymocytes from mice bearing a large, day-10 MOPC-315 tumor, but not thymocytes from normal mice, acquire the ability to generate an enhanced level of antitumor cytotoxicity upon in vitro stimulation with MOPC-315 tumor cells plus low concentrations (9.0–90 IU/ml) of exogenous interleukin-2 (IL-2) [23]. Here we show that the time interval between tumor inoculation and low-dose melphalan therapy as well as the magnitude of tumor burden at the time of the chemotherapy are important for the ability of the drug to render thymocytes more responsive to in vitro stimulation with MOPC-315 tumor cells plus low concentrations of recombinant IL-2 (rIL-2). Specifically, the chemotherapy was found to be effective in enhancing the thymic antitumor reactivity only if the mice bore a large, late-stage tumor. Comparison of thymocytes from untreated mice bearing a large, late-stage tumor to thymocytes from normal mice revealed that tumor-bearer thymocytes contained approximately a three-fold higher frequency of cytotoxic T lymphocyte precursors (CTLp) for MOPC-315-associated antigens. Following curative low-dose melphalan therapy of mice bearing a large, latestage MOPC-315 tumor, the frequency of CTLp for MOPC-315-associated antigens increased further, reaching a level approximately tenfold higher than that found among thymocytes of normal mice. At the same time, the frequency of CTLp for an antigenically unrelated allogeneic tumor (EL4) as well as the overall percentage of mature cells was not increased. The cells responsible for the exertion of the enhanced antitumor cytotoxicity following in vitro stimulation of thymocytes from mice treated with low-dose melphalan when they have a large, latestage MOPC-315 tumor are of the CD8+/CD4 phenotype. Thus, the enhanced level of antitumor cytotoxicity generated by thymocytes from mice that are treated with low-dose melphalan when they have a large, late-stage MOPC-315 tumor is due, at least in part, to the presence of an enlarged pool of CTLp specific for MOPC-315-associated antigens, which mature into CD8+/CD4 effector cells upon stimulation with MOPC-315 tumor cells plus low concentrations of rIL-2.supported by Research Grant CA-35761 from the National Cancer Institute and Research Grant EY-05945 from the National Eye Institute. This work is in partial fulfillment of the requirements for the Doctor of Philosophy degree of M. M. B. M. B. M. was supported by a Career Development Award CA-01350 from the National Cancer Institute.  相似文献   

2.
Summary A method is described whereby the differential staining of viable and nonviable unfixed cells, as observed by the dye-exclusion method, can be reproduced in glutaraldehyde-fixed preparations by staining with alcian blue. The results suggest that the differential staining is due, at least in part, to structural differences that are retained following aldehyde fixation. This work was supported by grants from the National Cancer Institute of Canada and the National Research Council of Canada. Recipient of a Research Studentship from the National Cancer Institute of Canada.  相似文献   

3.
Summary During methotrexate-induced differentiation of cultured human choriocarcinoma (BeWo) cells, proliferation is inhibited, morphologic and biochemical changes occur, and giant, often multinucleated, cells form. We have used the increase in cell volume as a marker of the mature syncytiotrophoblastlike phenotype. Uninduced and differentiated BeWo cells are not spherical, and theoretical considerations suggested that deviations in shape could result in significant errors in Coulter volume. To determine if the values obtained by electrical pulse sizing reflected the actual mass of BeWo cells, we have evaluated the relationship between Coulter volumes and intracellular water volumes obtained using a shape-independent estimate for eight cell types. A close correlation (r 2=0.97) was found, indicating that cell volume changes in populations of irregularly shaped cells can be accurately measured using a Coulter instrument. Supported by an operating grant from the National Cancer Institute of Canada. N.S.B. was a recipient of a studentship award from the Alberta Heritage Foundation for Medical Research. C.E.C. is a Senior Research Scientist of the National Cancer Institute of Canada. The McEachern Laboratory is a research facility of the Faculty of Medicine, University of Alberta, and the Cross Cancer Institute, Edmonton, Alberta.  相似文献   

4.
5.
A synthetic peptide (RS-83277) derived from the structure of human C-reactive protein (CRP) was previously shown to have antitumor activity in three different murine tumor models when administered in multilamellar vesicles (MLV). The therapeutic effects were comparable to those seen with MLV-encapsulated native CRP. The present study evaluated the therapeutic and immunomodulatory effects of administering CRP peptide RS-83277 MLV simultaneously with low-dose recombinant interleukin-2 (IL-2) to C57B1/6 mice bearing established pulmonary metastases of fibrosarcoma T241. Results demonstrated that the capacity of RS-83277 MLV to inhibit tumor metastases and prolong survival was significantly augmented by combination with 10 000 U/day IL-2 i.p. Treated animals showed no evidence of toxicity. By immunohistochemistry, increased Thy 1.2+ cells were detectable in lungs of RS-83277 MLV/IL-2-treated animals compared to those receiving RS-83277 MLV alone. Circulating tumor necrosis factor (TNF) and interferon (IFN) were not detectable in animals receiving RS-83277 MLV alone, but TNF was significantly elevated in animals receiving IL-2. In the presence of combination therapy, however, circulating TNF was not detectable. Results suggest that the combination of synthetic CRP peptide RS-83277 MLV and low-dose IL-2 offers a therapeutic advantage over either agent alone.This work was supported in part by grant CA49950 from the National Cancer Institute (B.P.B.), and grant 43618 from the National American Cancer Society (S.D.D.)  相似文献   

6.
Summary We compared the effects of defined medium, fetal bovine serum (FBS) and human serum (HuS) on the growth and responses to chemotherapeutic agents of human breast cancer cells in primary culture. Normal and tumor tissues were dissociated to small aggregates and single cells and seeded onto collagen-gel-coated wells in defined medium or medium supplemented with 5% FBS or 5% HuS. In all cases examined, defined medium and medium containing HuS were superior to medium containing FBS in supporting growth of both normal and tumor cell cultures. However, cultures in defined medium showed an initial cell loss. Cells from the same tumor cultured in different media varied in their responses to chemotherapeutic agents. In light of these results, medium supplemented with HuS, which promoted attachment of these cells in culture and stimulated their growth, should be the most appropriate nutrient environment for determining the effects of therapeutic agents on cells as it most closely resembles the in vivo situation. Because there were also variations in growth rates and chemosensitivities of tumor cells cultured in different human serum samples, we suggest that optimal conditions in which to culture these cells include the serum of the patient whose tumor is removed. This serum may provide host factors that influence cell growth and interact with exogenous factors. This work was supported by a grant from the National Cancer Institute of Canada and funds contributed by Mr. B. T. Wharton in memory of his wife, Nadia. J. T. Emerman is a research scholar of the National Cancer Institute of Canada.  相似文献   

7.
In the present study we demonstrate the ability of allogeneic M3 tumor cells to induce an antitumor response against the syngeneic tumor, when injected locally together with syngeneic B16 melanoma cells. The replacement of the allogeneic tumor cells with either syngeneic or allogeneic splenocytes had no effect on the growth of the syngeneic tumor. Systemic administration of both interleukin-2 (IL-2) and IL-6 did not affect the antitumor response induced by allogeneic tumor cells. When mice, previously injected with B16 and M3 cells, were rechallenged subcutaneously with B16 tumor cells at a different anatomical site, an inhibitory effect in some, but not all, experiments was observed. Systemic injections of either IL-2 or IL-6 did not alter the antitumor effects of the allogeneic and syngeneic tumor-cell mixtures. The significance of our results in developing immunotherapy modalities based on active immunization with allogeneic tumor cells and selected cytokines is discussed.This study was supported by a grant from the Israeli Cancer Association  相似文献   

8.
We evaluated the antitumor effect of an interleukin 2 (IL-2) slow delivery system, the IL-2 mini-pellet, in two murine solid tumor models, and also investigated the enhancement of its therapeutic effect by serial administration. The IL-2 mini-pellet contains 1 × 106 units of IL-2 and releases it slowlyin vivo. In our experiment, the IL-2 mini-pellet was administered subcutaneously near the tumor site in combination with the intravenous injection of lymphokine-activated killer (LAK) cells. When this regimen was given on days 8 and 11 after the subcutaneous inoculation of Meth A fibrosarcoma into BALB/c mice, tumor growth was significantly inhibited (p < 0.05) compared to tumor growth in untreated controls. Moreover, the IL-2 mini-pellet alone was also effective in inhibiting tumor growth. In another experiment, MH134 hepatoma was inoculated into C3H/He mice. Both administration of the IL-2 minipellet alone and in combination with LAK cells resulted in complete tumor regression in four of five mice. In a third experiment, serial administration of the IL-2 mini-pellet at 3- or 5-day intervals prolonged the suppression of Meth A fibrosarcoma growth in BALB/c mice. These results suggested that the IL-2 mini-pellet could be applied to cancer immunotherapy and that its antitumor effect could be prolonged by serial administration.  相似文献   

9.
Summary A multicellular tumor spheroid (MTS) model for head and neck cancers has been used to examine the immune function of fresh and 6-day interleukin-2(IL-2)-activated peripheral blood lymphocytes (PBL). MTS are individually cultured in the presence of effector cells, and the spheroids' growth is monitored by sizing them under an inverted microscope. Dose/response studies for IL-2 (0–100 U/ml) alone and for fresh unstimulated PBL (0–105 cells/MTS) showed no effects on MTS growth. IL-2-activated PBL (0–105 cells/MTS), in contrast, modulated MTS growth in a multiphasic pattern: MTS growth was unperturbed for the first 3 days and then growth inhibition occurred, followed by MTS disintegration. Histological analysis showed that intact MTS histoarchitecture correlated with unperturbed growth, and increasing cell sloughing and MTS dissolution and replacement by activated PBL correlated with growth inhibition and disintegration. Flow-cytometric sorting of lymphocyte subset populations indicated that it was the Leu19+CD3 cells that produced these growth-modulatory effects. In contrast to the initial LAK cell resistance of MTS, single-cell suspensions demonstrated significant lysis in standard 4-h chromium-release assays. Differences between single cells and MTS suggest a potential for tissue-like organization as a factor in lymphokine-activated killing.Supported in part by the First Independent Investigator Award (R29 CA46 251-01) (S. P. S.) of the National Cancer Institute. The Cancer Information Systems Core Facility used in this study was funded under the National Cancer Institute grant CA 16672  相似文献   

10.
Phenotypic stability of mouse mammary tumor cells cultured on collagen gels   总被引:1,自引:0,他引:1  
Summary This study demonstrates that phenotypic characteristics of androgen-responsive (AR) Shionogi mouse mammary tumors and androgen-independent (AI) derivatives can be maintained in culture. Cells were seeded onto collagen gels in medium containing 2% dextran-characoal-treated fetal bovine serum with or without 0.01 μg/ml dihydrotestosterone (DHT). Androgen-responsive tumors grew more rapidly than AI tumors in vivo and consequently, cells from AR tumors cultured in DHT-containing medium grew faster than cells in DHT-deprived medium and cells from AI tumors. Androgen-responsive tumors had a sheetlike growth pattern; AI tumors formed clumps or irregular cords of cells. Cells from AR tumors cultured in the presence of DHT formed confluent pavements, whereas cells maintained in the absence of DHT and cells from AI tumors formed clusters or cords of cells. Ultrastructurally, cells of AR tumors were elongated; cells of AI tumors were smaller and rounder. These cellular morphologies persisted in culture. Tumorigenicity of cells was assayed by injecting cells s.c. into host mice. Tumors arising from cells of freshly dissociated AR tumors and cells of AR tumors cultured in the presence of DHT appeared more rapidly and grew faster in intact males than in castrated males and intact females. Tumors arising from cells cultured in the absence of DHT and from freshly dissociated or cultured cells of AI tumors had identical rates of appearance and growth in all hosts. This culture system permits these cells to retain their state of malignant progression in vitro and should be a useful model for studying the origin of heterogeneity within tumors and its role in tumor behavior. This work was supported by a grant from the National Cancer Institute of Canada. J. T. E. is a Research Scholar of the National Cancer Institute of Canada.  相似文献   

11.
Summary Infusion of normal recipient mice with suppressor T cells from donors bearing a progressive Meth A fibrosarcoma results in a diminished capacity of the recipients to generate concomitant and postexcision antitumor immunity. The passive transfer of suppressor cells which prevented the generation of immunity to the Meth A fibrosarcoma did not affect the capacity of the recipients to reject an allogeneic tumor. The data provides direct evidence in support of the hypothesis that suppressor T cells, generated at later stages of growth of Meth A fibrosarcoma, function to down-regulate an already acquired mechanism of concomitant immunity.This work was supported by Grants CA-16642 and CA-17794 from the National Cancer Institute, Grant RR-05705 from the Division of Research Resources, NIH, and a grant from R. J. Reynolds Industries, Inc  相似文献   

12.
This work was supported by a grant and research associateship to N.A. from the Medical Research Council of Canada and the National Cancer Institute of Canada.  相似文献   

13.
Introduction We and others previously observed immunosurveillance against transplantable tumors in mice, and enhancement thereof by blockade of negative regulation by T reg cells or the NKT-IL-13-myeloid cell-TGF-β regulatory circuit. However, it was unknown whether natural immunosurveillance inhibits growth of completely spontaneous autochthonous tumors, and whether it can be improved by inhibition of negative regulation. Materials and methods To examine the existence of T cell-mediated immunosurveillance against spontaneous tumors, BALB-neuT mice were treated with anti-CD4 and/or anti-CD8. A role for IL-13 in the suppression of immunosurveillance was investigated by treating mice with IL-13 inhibitor. Results We show that even spontaneous autochthonous breast carcinomas arising in Her-2/neu transgenic mice appear more quickly when the mice are depleted of T cells, evidence for T-cell mediated immunosurveillance slowing tumor growth. This immunosurveillance could be further enhanced by blockade of IL-13 (but not IL-4) which slowed the appearance of these autologous tumors compared to control antibody-treated mice. Conclusion Thus, even completely spontaneous, autochthonous breast cancers can be controlled in part by natural immunosurveillance, and blockade of negative regulation can improve this control. This work was in part supported by the Intramural Research Program of the NIH, National Cancer Institute, Center for Cancer Research.  相似文献   

14.
Summary A method is described whereby the differential staining of viable and nonviable unfixed cells, as observed by the dye-exclusion method, can be reproduced in glutaraldehyde-fixed preparations by staining with alcian blue. The results suggest that the differential staining is due, at least in part, to structural differneces that are retained following aldehyde fixation. This work was supported by grants from the National Cancer Institute of Canada and the National Research Council of Canada.  相似文献   

15.
Summary This paper describes some current work pertaining to transformation of cells by oncogenic viruses. Part I includes: (1) the effect of a deoxyribonucleic acid (DNA) tumor virus (SV40) on the antigenic characteristics of transformed cells; (2) in vitro and in vivo methods of detecting virus-specific surface antigens; (3) the role that the host cell may play in the expression of virus-coded antigens; and (4) the presence of virus-induced antigens as a possible mechanism of the apparent nononcogenicity of certain virus variants. Part II discusses (1) the physicochemical properties of the nucleic acid of a ribonucleic acid (RNA) tumor virus-the Moloney sarcoma-leukemia virus (MSV-MLV) complex —(2) a preliminary analysis of viral RNA replication in cells transformed by MSV-MLV, and (3) application to human tumors. Supported in part by Research Grant CA 04600 and by Research Contract PH 43-68-678 within the Special Virus-Cancer Program, National Cancer Institute, National Institutes of Health. Recipient of Research Career Development Award 5-K3-CA 38,614 from the National Cancer Institute, National Institutes of Health  相似文献   

16.
Direct intratumoral injection of interleukin-2 (IL-2) was evaluated in a murine model. Balb/c mice received 5 × 104 Line 1 alveolar carcinoma cells (L1C2) by subcutaneous injection. On the third day following tumor implantation, mice received injections of IL-2 (5 × 103–5 × 104 units) or diluent twice daily, either by i. p. or intratumoral injection, 5 days/week for 3 weeks. Intratumoral injection of 5 × 104 units IL-2 significantly reduced tumor volume (P <0.05 versus control), increased median survival time (P = 0.0001), and resulted in a 23.5% cure rate (P = 0.008). There were no long-term survivors in the other treatment groups. Both tumor-infiltrating lymphocytes (TIL) and splenic lymphocytes isolated directly from IL-2-treated mice demonstrated enhanced cytolytic activity compared to diluent-treated controls. To determine whether non-T-cell-mediated antitumor responses were active in our model, intratumoral immunotherapy was evaluated in athymic Balb/cnu/nu mice. In order to decrease the recruitment of lymphocyte precursors, nude mice were splenectomized and received cyclophosphamide prior to tumor injection and IL-2 therapy. Intratumoral IL-2 immunotherapy also significantly decreased tumor volume in these immunodeficient mice (P <0.02), but did not lead to long-term survival. We conclude that both TIL and splenic lymphocytes are activated in vivo in response to intratumoral IL-2 immunotherapy, suggesting that intratumoral therapy with IL-2 activates both local and systemic antitumor responses.Supported by the Tobacco-Related Disease Research Program of the University of California, the Cancer Research Coordinating Committee, the Jonsson Cancer Center Foundation, and Veterans Administration Medical Research Funds  相似文献   

17.
Interferon-γ-inducing factor/interleukin-18 is a novel cytokine that reportedly augments natural killer (NK) activity in human and mouse peripheral blood mononuclear cell cultures in vitro and has recently been designated IL-18. In this study, IL-18 exhibited significant antitumor effects in BALB/c mice challenged intraperitoneally (i.p.) with syngeneic Meth A sarcoma when administered i.p. on days 1, 2 and 3 after challenge. Intravenous (i.v.) administration also induced antitumor effects in the tumor-bearing mice; however, subcutaneous (s.c.) administration did not. When mice were twice pretreated with 1 μg IL-18 3 days and 6 h before tumor challenge, all mice survived whereas control mice died within 3 weeks of challenge. Inhibitory effects on Meth A cell growth in vitro were not observed with either IL-18 or interferon γ. The effects of IL-18 pretreatment were abrogated by abolition of NK activity after mice had been injected with anti-asialo GM1 antibody 48 h before and, 24 h and 72 h after tumor challenge. Mice pretreated with IL-18 and surviving tumor challenge resisted rechallenge with Meth A cells but could not reject Ehrlich ascites carcinoma, and spleen cells from the resistant mice, but not control mice, exhibited cytotoxic activity against Meth A cells in vitro after restimulation with mitomycin C-treated Meth A cells for 5 days. The effector cells in the spleen cell preparations from resistant mice appear to be CD4+ cells because cytolytic activity was significantly inhibited after depletion of this subset by monoclonal antibodies and complement. In conclusion, IL-18 exhibits in vivo immunologically (primarily NK) mediated antitumor effects in mice challenged with syngeneic Meth A sarcoma and induces immunological memory and the generation of cytotoxic CD4+ cells. Received: 17 September 1996 / Accepted: 8 November 1996  相似文献   

18.
Previous studies have shown inhibition of cervical cancer cell growth by treatment with high concentrations of IL-2. In the present study, we evaluated the in vitro and in vivo effects of recombinant human IL-2 on HPV-associated tumor cells (3T3-16). Treatment of 3T3-16 cells with rhIL-2 for 72 h inhibited cell growth in a dose-dependent manner and this effect was evidenced at nanomolar concentrations. These tumor cells expressed mRNA for beta and gamma subunits of the IL-2 receptor, which are required for signal transduction. In experiments to explore the effect of IL-2 on the growth of the HPV-associated tumor, mice received rhIL-2 through different routes: (i) intraperitoneal; (ii) subcutaneous, at the tumor inoculation site; or (iii) subcutaneous, distant from the tumor inoculation site. An effective antitumor response was observed only in those animals that received IL-2 at the tumor site (P<0.01). These results indicate the potential adequacy of therapeutic strategies based on local administration of rhIL-2 for cervical carcinoma, not only based on the ability of this cytokine to stimulate cellular-mediated immunity but also because of its direct effects on tumor cells.  相似文献   

19.
Tumors exhibit a variety of strategies to dampen antitumor immune responses. With an aim to identify factors that are secreted from tumor cells, we performed an unbiased mass spectrometry-based secretome analysis in lung cancer cells. Interleukin-6 (IL-6) has been identified as a prominent factor secreted by tumor cells and cancer-associated fibroblasts isolated from cancer patients. Incubation of dendritic cell (DC) cultures with tumor cell supernatants inhibited the production of IL-12p70 in DCs but not the surface expression of other activation markers which is reversed by treatment with IL-6 antibody. Defects in IL-12p70 production in the DCs inhibited the differentiation of Th1 but not Th2 and Th17 cells from naïve CD4+ T cells. We also demonstrate that the classical mitogen-activated protein kinase, ERK5/MAPK7, is required for IL-6 production in tumor cells. Inhibition of ERK5 activity or depletion of ERK5 prevented IL-6 production in tumor cells, which could be exploited for enhancing antitumor immune responses.Subject terms: Cancer microenvironment, Extracellular signalling molecules  相似文献   

20.
The current studies demonstrate that MOPC-315 tumor cells secrete large amounts of interleukin-10 (IL-10), which contributes to the inhibitory activity of MOPC-315 culture supernatants for the in vitro generation of antitumor cytotoxicity by MOPC-315-immune spleen cells. Moreover, addition of neutralizing monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of cells from the tumor infiltrated spleens of mice bearing a large MOPC-315 tumor resulted in the generation of enhanced anti-MOPC-315 cytotoxicity. In contrast, addition of monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of splenic cells from mice that are in the final stages of immune-mediated tumor eradication as a consequence of low-dose melphalan (l-phenylalanine mustard; L-PAM) therapy (and whose spleens no longer contain metastatic tumor cells) did not lead to enhancement in the in vitro generation of antitumor cytotoxicity. The cessation of IL-10 secretion as a consequence of low-dose L-PAM therapy of MOPC-315 tumor bearers was found to be accompanied by the acquisition of the ability to secrete interferon (IFN) by the splenic cells. In addition, by day 2 after low-dose L-PAM therapy a drastic decrease in the amount of IL-10 secreted by the s.c. tumor nodules was noted, which preceded the accumulation of tumor-infiltrating lymphocytes capable of secreting IFN. Thus, low-dose L-PAM therapy of mice bearing a large MOPC-315 tumor leads to a shift in cytokine production from a Th2-type cytokine to a Th1-type cytokine, and it is conceivable that this shift in cytokine production plays an important role in the low-dose L-PAM-induced acquisition of antitumor immunity by hitherto immunosuppressed mice bearing a large MOPC-315 tumor.Supported by research grant IM-435 from the American Cancer Society and CA54413 from the National Cancer InstituteIn partial fulfillment of the requirements for the Doctor of Philosophy DegreeRecipient of career development award CA-01350 from the National Cancer Institute  相似文献   

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