-
British Journal of Cancer Sep 1991In vitro drug sensitivity of leukaemic cells might be influenced by the contamination of such a sample with non-malignant cells and the sample source. To study this,... (Comparative Study)
Comparative Study
In vitro drug sensitivity of leukaemic cells might be influenced by the contamination of such a sample with non-malignant cells and the sample source. To study this, sensitivity of normal peripheral blood (PB) lymphocytes to a number of cytostatic drugs was assessed with the MTT assay. We compared this sensitivity with the drug sensitivity of leukaemic cells of 38 children with acute lymphoblastic leukaemia. We also studied a possible differential sensitivity of leukaemic cells from bone marrow (BM) and PB. The following drugs were used: Prednisolone, dexamethasone, 6-mercaptopurine, 6-thioguanine, cytosine arabinoside, vincristine, vindesine, daunorubicin, doxorubicin, mafosfamide (Maf), 4-hydroperoxy-ifosfamide, teniposide, mitoxantrone, L-asparaginase, methotrexate and mustine. Normal PB lymphocytes were significantly more resistant to all drugs tested, except to Maf. Leukaemic BM and PB cells from 38 patients (unpaired samples) showed no significant differences in sensitivity to any of the drugs. Moreover, in 11 of 12 children with acute leukaemia of whom we investigated simultaneously obtained BM and PB (paired samples), their leukaemic BM and PB cells showed comparable drug sensitivity profiles. In one patient the BM cells were more sensitive to most drugs than those from the PB, but the actual differences in sensitivity were small. We conclude that the contamination of a leukaemic sample with normal PB lymphocytes will influence the results of the MTT assay. The source of the leukaemic sample, BM or PB, does not significantly influence the assay results.
Topics: Adult; Antineoplastic Agents; Bone Marrow; Cell Survival; Cells, Cultured; Child; Drug Screening Assays, Antitumor; Humans; Leukemia, Myeloid, Acute; Lymphocytes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Reference Values
PubMed: 1911186
DOI: 10.1038/bjc.1991.333 -
Immunology Jul 1991A single systemic dose of cyclophosphamide (CY) has been shown to enhance cellular immunity in a variety of antigen models. The immunoenhancing effects of CY have been...
A single systemic dose of cyclophosphamide (CY) has been shown to enhance cellular immunity in a variety of antigen models. The immunoenhancing effects of CY have been attributed to its ability to selectively abrogate suppressor cell function. Previous studies from our group have demonstrated that local administration of distinct cytostatic drugs at the sensitization site can induce a similar enhancement of delayed-type hypersensitivity as systemic CY, with the obvious advantage of avoiding systemic side-effects. In the present study we investigated the effects of local administration of an optimally immunopotentiating dose of the active CY-derivative Z 7557 and, in selected experiments, of etoposide (VP-16) and systemic CY on mononuclear cells in draining lymph nodes. Whereas CY caused a long-lasting and marked depletion of B-cell areas, locally administered Z 7557 and VP-16 relatively spared B cells and even induced an increase in B- and T-cell numbers in (keyhole limpet haemocyanin-) sensitized mice. At Day 4 the CD4/CD8 ratio was slightly reduced in drug-treated mice. Interestingly, drug treatment reduced the proportion of interdigitating cells staining with the monoclonal antibodies NLDC-145 and MIDC-8. Upon isolation, dendritic cells (DC) from sensitized, Z 7557-treated mice showed longer dendritic protrusions and an enhanced accessory cell function compared to DC from saline-treated controls. These findings suggest that immunoenhancing effects of cytostatic drugs may occur via an effect on DC.
Topics: Adjuvants, Immunologic; Animals; Cyclophosphamide; Dendritic Cells; Female; Flow Cytometry; Injections, Subcutaneous; Lymph Nodes; Lymphocyte Subsets; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL
PubMed: 1879874
DOI: No ID Found -
Clinical and Experimental Immunology Jun 1991In previous work, we have shown that local administration of active cyclophosphamide (CY) derivatives, or other cytostatic drugs, at the sensitization site induced a...
In previous work, we have shown that local administration of active cyclophosphamide (CY) derivatives, or other cytostatic drugs, at the sensitization site induced a similar immunopotentiation to that of systemic CY. Since it is well documented that CY can inhibit suppressor cells, it was proposed that immunoenhancement by locally administered drugs might be based on a similar principle. The objective of the present study was to test this hypothesis, using an experimental model of Ts mediated suppression of delayed type hypersensitivity to sheep erythrocytes. In this model, mice are made tolerant to sheep erythrocytes by i.v. injection of a high dose of sheep erythrocytes. Local treatment of sheep erythrocytes-tolerant mice with the active CY derivative Z7557 at the site of attempted sensitization reversed suppression in a dose-dependent manner. Local treatment with the cytostatic drug etoposide (VP-16) and systemic CY treatment were also effective. In transfer experiments, the function of afferently acting suppressor cells was blocked by local treatment with Z7557 or systemic CY. These data support the concept of anti-suppressor cell activity of locally administered cytostatic drugs. As with CY, the pharmacological basis of this effect remains to be determined.
Topics: Administration, Topical; Animals; Antineoplastic Agents; Cyclophosphamide; Erythrocytes; Hypersensitivity, Delayed; Mice; Mice, Inbred BALB C; Sheep; T-Lymphocytes, Regulatory
PubMed: 1828396
DOI: No ID Found -
Cancer Immunology, Immunotherapy : CII 1991The antineoplastic efficacy of human interleukin-2 (IL-2) in autochthonous methylnitrosourea-induced mammary carcinoma and in acetoxymethyl-methyl-nitrosamine-induced...
The antineoplastic efficacy of human interleukin-2 (IL-2) in autochthonous methylnitrosourea-induced mammary carcinoma and in acetoxymethyl-methyl-nitrosamine-induced colorectal carcinoma of Sprague Dawley rats has been investigated. Under the conditions applied, IL-2 was non-toxic. In the mammary carcinoma IL-2 was therapeutically inactive. In the colorectal carcinoma, 1200 U IL-2/day exhibited significant antitumour activity in established tumours as well as in tumours treated "prophylactically" before their manifestation (P less than 0.05). The effect of IL-2 seemed to be more pronounced when given before manifestation of colorectal tumours (T/C = 8.7% vs 17.8% in established tumours). The differential sensitivity of the autochthonous mammary and colorectal carcinoma may be explained by differences in their proliferation rates and differences in volumes at the beginning of IL-2 therapy. IL-2 seems to be preferentially active in small tumours with a low proliferation rate, a feature typical of colon tumours.
Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinogens; Colorectal Neoplasms; Cyclophosphamide; Dimethylnitrosamine; Female; Interleukin-2; Male; Mammary Neoplasms, Experimental; Methylnitrosourea; Neoplasm Transplantation; Rats; Rats, Inbred Strains
PubMed: 1868493
DOI: 10.1007/BF01756601 -
Blood Dec 1990The knowledge about drug resistance in childhood leukemias and acute lymphoblastic leukemia (ALL) in general is limited. This is because of the lack of a suitable in... (Comparative Study)
Comparative Study
The knowledge about drug resistance in childhood leukemias and acute lymphoblastic leukemia (ALL) in general is limited. This is because of the lack of a suitable in vitro drug sensitivity assay, which is in part due to low in vitro ALL cell survival. We recently adapted the highly efficient 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay to test cells from ALL patients and showed that its results were comparable with those of the DiSC assay, up to now the most valid but laborious assay. In this study, in vitro drug sensitivity was assessed in cells from 82 children with leukemia, 79 of whom had ALL, with the MTT assay. Dose response curves were obtained for 6-mercaptopurine, 6-thioguanine (6-TG), prednisolone (Pred), daunorubicin (DNR), vincristine (VCR), cytosine arabinoside (Ara-C), L-asparaginase (L-Asp), mafosfamide, and mustine. A cytotoxic effect of methotrexate could be detected in only a few cases. Large interindividual differences in drug sensitivity were detected. Compared with leukemia cells from newly diagnosed patients, leukemia cells from relapsed patients were significantly more in vitro resistant to 6-TG, Pred, Ara-C, mafosfamide and mustine but not to DNR, VCR, and L-Asp. Improvements of culture medium and methods to increase MTT reduction were studied. From 10 components tested, addition of insulin and bovine serum albumin to serum-containing medium improved ALL cell survival. Addition of succinate did not increase the amount of MTT reduction. We conclude that the in vitro MTT assay highly facilitates large-scale studies on drug resistance of ALL patients that can lead to rational improvements in existing treatment protocols.
Topics: Asparaginase; Cells, Cultured; Child; Coloring Agents; Culture Media; Cyclophosphamide; Cytarabine; Daunorubicin; Dose-Response Relationship, Drug; Drug Resistance; Drug Screening Assays, Antitumor; Humans; Mechlorethamine; Mercaptopurine; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prednisolone; Tetrazolium Salts; Thiazoles; Thioguanine; Vincristine
PubMed: 2257305
DOI: No ID Found -
Blood Apr 1990We analyzed data from 263 patients with acute myelocytic leukemia (AML) autografted in first remission (CR) during the period from January, 1982 to January, 1987 at one...
We analyzed data from 263 patients with acute myelocytic leukemia (AML) autografted in first remission (CR) during the period from January, 1982 to January, 1987 at one of 34 centers in the European Bone Marrow Transplant Group. The median age of patients was 30 years (range, 1 to 65). The median interval between achieving CR and autografting was 5 months (range, 1 to 23). Of the 263 patients, 131 patients received cytoreductive regimens that included total body irradiation (TBI); the remainder received various combinations of cytotoxic drugs. Sixty-nine patients received autologous marrow purged in vitro with mafosfamide, and 194 received unpurged marrow. The median follow-up was 28 months (range, 12 to 97). For patients with standard risk AML in CR1 autografted after TBI (n = 107), the leukemia-free survival (LFS) was higher, and the probability of relapse was lower in recipients of purged than of unpurged marrow (63% versus 34%, P = .05 and 23% versus 55%, relative risk 0.34, P = .005, respectively). The superior results of purging were most obvious in patients autografted within 6 months of achieving CR (probability of relapse, 20% versus 61%, P = .01). Patients with longer intervals between CR and autografting had higher LFS and lower probability of relapse than those autografted early in CR (intervals greater than 9 months, 7 to 9 months, 4 to 7 months, and less than or equal to 3 months: LFS = 56%, 40%, 35%, 27%, P = .007, probability of relapse = 25%, 56%, 59%, 67%, P = .005; respectively). We conclude that marrow purging with mafosfamide may be valuable for patients autografted early in first CR.
Topics: Adolescent; Adult; Aged; Antineoplastic Agents; Bone Marrow; Bone Marrow Transplantation; Child; Child, Preschool; Cyclophosphamide; Europe; Female; Humans; Infant; Leukemia, Myeloid, Acute; Male; Middle Aged; Recurrence; Remission, Spontaneous; Transplantation, Autologous
PubMed: 2328313
DOI: No ID Found -
Cancer Immunology, Immunotherapy : CII 1990The effectiveness of adoptive immunotherapy in eliminating minimal residual disease in tumour-bearing mice after bone marrow transplantation was tested. This model...
The effectiveness of adoptive immunotherapy in eliminating minimal residual disease in tumour-bearing mice after bone marrow transplantation was tested. This model mimics the human clinical condition when autologous bone marrow was purged ex vivo of leukaemia with mafosfamide or was not purged, and stored in liquid nitrogen before transplantation. Animals with minimal residual disease were prepared with marrow-ablative but leukaemia-noncurative doses of cyclophosphamide (CY) and total body irradiation followed by bone marrow transplantation. The next day after transplantation the recipients were injected with splenocytes immunized against the leukaemia cells (Imm-SPL) or monoclonal antibody (mAb). All the control mice died from leukaemia relapse, but 51% of purged bone marrow recipients, which received Imm-SPL, were cured. In similar conditions mAb did not exert a therapeutic effect. Imm-SPL were not able to eradicate minimal residual disease in the recipients of nonpurged bone marrow. Thus, in an animal model, we demonstrated that purging of bone marrow before grafting seems to be indispensable for successful adoptive immunotherapy of minimal residual disease (MRD) after autologous bone marrow transplantation.
Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; Bone Marrow; Bone Marrow Cells; Bone Marrow Transplantation; Combined Modality Therapy; Cyclophosphamide; Female; Immunotherapy, Adoptive; Leukemia L1210; Male; Mice; Mice, Inbred BALB C
PubMed: 2289201
DOI: 10.1007/BF01741728 -
International Journal of Cell Cloning Jan 1990The results of in vivo studies conducted with colony-stimulating factors (CSFs) in autologous bone marrow transplantation (ABMT) are summarized. Our own data obtained... (Review)
Review
The results of in vivo studies conducted with colony-stimulating factors (CSFs) in autologous bone marrow transplantation (ABMT) are summarized. Our own data obtained from in vitro models dealing with the use and possible applications of CSFs in ABMT are reported. In particular, we show data concerning: 1) the use of interleukin 3, granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 1 to expand hematopoietic progenitor cell growth in the early phase of ABMT; 2) in vitro marrow purging with Mafosfamide and GM-CSF in chronic myelogenous leukemia; and 3) growth requirements of MY10-derived leukemic colony-forming units. The use of CSFs, alone or in combination, may provide us with new strategic approaches for the treatment of acute and chronic leukemias. CSFs in combination with chemotherapeutic agents are very promising agents for purging marrow prior to ABMT.
Topics: Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Colony-Stimulating Factors; Cyclophosphamide; Hematopoiesis; Humans; In Vitro Techniques; Leukemia, Myeloid; Neutropenia; Transplantation, Autologous
PubMed: 2182739
DOI: 10.1002/stem.5530080725 -
Cancer Immunology, Immunotherapy : CII 1990The aim of the present study was to analyze further the immunopotentiating effects of low doses of oxazaphosphorines. We examined 4-hydroperoxycyclophosphamide (4-HC)...
The aim of the present study was to analyze further the immunopotentiating effects of low doses of oxazaphosphorines. We examined 4-hydroperoxycyclophosphamide (4-HC) and mafosfamide, which degrade spontaneously in water without requiring liver enzymes to become active. Both drugs, at concentrations ranging from 0.01 microM to 1 microM, enhanced mitogenic responses of human lymphocytes. Higher concentrations were toxic. Acrolein, which is one of the degradation products of oxazaphosphorines, had similar effects. Immunopotentiation was not monocyte-dependent. Attempts to inactivate released acrolein with human serum reduced toxicity but the immunostimulating property of the drugs remained Similar effects were noted when lymphocytes were exposed to acrolein dissolved in serum. 2-Mercaptoethane-sulfonate (mesna), which is highly reactive with acrolein, reduced the toxicity of solutions of both oxazaphosphorines and acrolein. Immunopotentiation was not clearly demonstrable since mesna itself enhanced the responses. Pretreatment of lymphocytes with 4-HC or mafosfamide did not reduce the capacity of concanavalin A to induce suppressor cells. It is speculated that acrolein may play a role in oxazaphosphorine-induced enhancements of immune responses.
Topics: Acrolein; Aldehydes; Antineoplastic Agents; Concanavalin A; Cyclophosphamide; Humans; Immunity, Cellular; Lymphocytes; Mitogens; Mitosis; T-Lymphocytes; T-Lymphocytes, Regulatory
PubMed: 2143101
DOI: 10.1007/BF01789172 -
Clinical and Experimental Immunology Nov 1989The immunomodulating effects of two locally administered cytostatic drugs, the active cyclophosphamide-derivative Z 7557 and the plant alkaloid VP-16, were compared with...
The immunomodulating effects of two locally administered cytostatic drugs, the active cyclophosphamide-derivative Z 7557 and the plant alkaloid VP-16, were compared with the effects of systemically administered cyclophosphamide and several established adjuvants: Freund's complete adjuvant, dextran sulphate, and dimethyl dioctadecyl ammonium bromide (DDA). All agents tested promoted the development of delayed-type hypersensitivity (DTH) to keyhole limpet haemocyanin (KLH) in mice. Locally administered cytostatic drugs were the most effective immunostimulatory compounds, whereas DDA was the least toxic agent tested. In order to increase the effectiveness and/ or reduce the toxicity of these agents we tested the efficacy of combinations of cytostatic drugs and DDA to enhance DTH. The results show that DDA and suboptimal amounts of locally administered cytostatic drugs act synergistically on DTH.
Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; Cyclophosphamide; Drug Synergism; Etoposide; Hemocyanins; Hypersensitivity, Delayed; Immunization; Male; Mice; Mice, Inbred BALB C; Quaternary Ammonium Compounds; Surface-Active Agents
PubMed: 12412759
DOI: No ID Found