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V Combaret

Publications and source records attributed to V Combaret.

At least 55 records · Page 3Linked to original sources
PubMed1990

Lymphokine-activated killer cell expansion for clinical trials of adoptive immunotherapy with interleukin-2: optimization of the culture technique.

On leukopheresis products obtained from patients included in a protocol interleukin-2/lymphokine-activated killer (IL-2/LAK) cell therapy, we analyzed, in parallel with the standard culture and on large volumes of these products, different parameters which could either improve LAK cell enhancement or simplify the procedure. We demonstrated first that purification of the mononuclear cells from the leukopheresis product before its culture is not required. An excess of red blood cells and granulocytes (up to 50%) in nonpurified samples improved both the mononuclear cell recovery in short-term culture (4 days) and the activation of LAK cells when the total nuclear cell concentration did not exceed 3 X 10(6)/ml. Different factors can contribute to this enhancing effect: the presence of red blood cells, the liberation of cytokines by granulocytes, or the loss of a population of activated lymphocytes, with liberation of cytokines by granulocytes, or the loss of a population of activated lymphocytes, with larger size and density than resting lymphocytes, during the separation. Supplementation of the medium with 2% heat-inactivated autologous plasma obtained before any treatment rather than with 2% pooled human AB serum does not modify the mononuclear cell recovery in 4-day culture, but it does enhance LAK activity. The inhibitory effect of heat-inactivated autologous plasma on proliferation and activation of LAK cells was never observed, suggesting the absence of suppressive factors in the plasma of the 23 analyzed patients. Similarly, autologous plasma did not modify natural killer and LAK cell functions when added during the cytotoxic assay.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Evaluation of a modified immunomagnetic procedure for the purging of neuroblastoma cells from bone marrow].

The immunomagnetic depletion method for removing tumor cells from bone marrow, previously refined using a Burkitt lymphoma model, was tested with neuroblastoma cells. The efficiency of depletion was quantified by immunofluorescence with a detection limit of 3.3 log of cell depletion corresponding to the elimination of 99.84% of an initial tumor cell content of 10%. A panel of five monoclonal antibodies (UJ13A; UJ127.11; UJ181.4; alpha-Thy1; H11) purged 2.8 log of SKNBE and LAN-1 cells, while two of these antibodies as single agents allowed only for a 1.7 log (UJ13A) and a 1.7 to 2.0 log (alpha-Thy1) depletion. This underlines the advantage of an antibody panel for neuroblastoma purging. The new antibody S-L 11.14, an IgG2a against small cell lung cancer which recognizes 90% of neuroblastoma cells purged 2.8 log.

Antibodies, Monoclonal↗
PubMed1990

[Adoptive immunotherapy with interleukin 2 in oncology].

Forty-seven patients with renal carcinoma were included in first line or rescue protocols of immunotherapy including IL2 alone or in association with LAK cells, INF alpha or TNF. The toxicity was mild and the mortality was 2% (1 patient). The response rate was 26%. Nineteen children with neuroblastoma received IL2 either alone or in combination with LAK cells. The morbidity and mortality were higher in patients with end stage disease who had previously received high dose and prolonged chemotherapy. In contrast, the toxicity was mild and transient in patients treated in the months following autologous bone marrow transplantation. The only complete response observed was in 1 child treated with IL2, 4 months after high dose chemotherapy and ABMT. Immunological analysis showed that the immunomodulatory effect of IL2 is very different depending on whether IL2 is used alone or in combination with other cytokines; moreover, the biological effect of IL2 is dependent on the immunological status of the patients prior to IL2 therapy.

Adenocarcinoma↗
PubMed1989

Clinical value of N-myc oncogene amplification in 52 patients with neuroblastoma included in recent therapeutic protocols.

Southern blot analysis of neuroblastoma (NB) cell DNA from 52 patients (58 samples) allowed the detection of an N-myc amplification on three of the 13 BM samples and three of 13 tumor samples at diagnosis, on two of 17 tumor samples taken after induction therapy, on three of seven BM samples and two of the five local tumor samples taken after relapse. N-myc was amplified in two of the 15 patients with stage I to III NB and in 10 of the 36 patients with stage IV neuroblastoma over 1 year of age. Conclusions from the analysis are as follows: first tumor samples obtained on previously treated patients are histologically modified and detection of N-myc amplification is not accurate; consequently N-myc amplification must be defined at diagnosis. Surgical biopsies of the primary tumors can, however, be delayed and malignant cells obtained by ultrasound-guided punctures or analyzed on bone marrow samples if they represent more than 50% of the total population. Second, any attempt to define the prognostic value must be performed on a group of patients treated with a new aggressive protocol of chemotherapy; it will require a multiparametric analysis including, in particular, results of an extensive clinical staging at diagnosis and histological criteria.

Child↗
PubMed1989

Interleukin-2 with and without LAK cells in metastatic renal cell carcinoma: the Lyon first-year experience in 20 patients.

Thirty-one patients with metastatic renal cell carcinoma were seen at the Centre Léon Bérard from October 1987 to October 1988. According to our protocol, 11 were excluded leaving 20 in the study. The median age was 55 years (range 36 to 79 years). The median number of metastases was 9 (range 2 to 29) and the median number of metastatic sites was 3 (range 1 to 4). Seventeen patients received a continuous infusion of recombinant interleukin-2 (rIL-2) of 3 x 10(6) U/m2/day, on days 1 to 5, with lymphapheresis on days 7 to 10 and IL-2 + LAK on days 11 to 15. Three patients received IL-2 alone. The clinical toxicity of IL-2 was as expected (100% fever, 88% erythema, 88% vomiting, 87% weight gain, 76% oliguria, 76% diarrhoea, 70% pruritus, 70% weakness, 41% severe hypotension, 41% acute renal failure, 33% disorientation, 23% respiratory distress, 12% ventilation and 5% coma) with no toxic deaths. Other toxicity was mild (median platelet nadir was 93,000 and median nadir of Hb 8.1 g/dl) except for the creatinine level which was found to be between 200 and 400 mumol/l in 45% of the courses and over 400 mumol/l in 24% of the courses. Eight capillary leak syndromes were observed. Among the three patients receiving IL-2 alone, one PD, one SD and one early toxicity were recorded. Among 15 evaluable patients receiving IL-2 + LAK, three had PR (20%) and two mixed response (PR and progression before 2 months); two had stable disease and eight had progression. No clinical or biological factor was able to predict response. However, the five objective responses were observed among the eight patients with a capillary leak syndrome. Lymphocyte peaks or platelet nadir were not related to response in this group of patients. The median number of harvested mononuclear cells was 9.8 x 10(10) and the median number of mononucleated cells reinjected was 5.9 x 10(10).

Carcinoma, Renal Cell↗
PubMed1989

Immunological detection of neuroblastoma cells in bone marrow harvested for autologous transplantation.

In about 50% of patients with stage IV neuroblastoma, micrometastases are present in the bone marrow when it is harvested for an autograft to follow induction therapy, and the risk of graft contamination by neuroblastoma cells has been the rationale for the use of a purging procedure. However, bone marrow metastases are detected with trephine biopsies which only explore the sites biopsied and do not reflect potential contamination of the pooled marrow harvested for autograft. A two-colour fluorochrome labelling method is described which permits as few as 1 neuroblastoma cell in 100,000 normal bone marrow cells from the autograft to be detected. Three monoclonal antibodies (UJ13A, H11 and 11.14) which react with neuroblastoma cells are used as single reagent in combination with a fourth anti-panleucocyte antibody. This method requires only 2 h for the analysis of three million marrow cells from the autograft, and is more effective than alkaline phosphatase staining with the same monoclonal antibodies. Results were compared with conventional techniques (four biopsies and four aspirates) carried out at the same time in 34 consecutive patients. Of 18 cases with negative aspirates and biopsies, neuroblastoma cells were detected in two autografts by the immunological method. Of 16 cases with positive aspirates and/or biopsies, 10 autografts were positive by the immunological method and six were negative. Thus, marrow micrometastases were detected in 16 of the 34 patients, but the autograft contained malignant cells in only 12 of these patients and the immunological analysis demonstrated that the use of a purging procedure allowed the elimination of neuroblastoma cells from the autograft before its reinjection to the patients.

Antibodies, Monoclonal↗
PubMed1989

Bone marrow metastases in small cell lung cancer: detection with magnetic resonance imaging and monoclonal antibodies.

The detection of bone marrow involvement might be of prognostic value and may influence therapeutic decisions in small cell lung cancer. By unilateral bone marrow aspiration and biopsy, evidence of bone marrow metastases is seen in 15-30% of patients with this disease. Since magnetic resonance imaging of the lower body and immunostaining with monoclonal antibodies have recently been shown to be very sensitive detection methods, we investigated the value of these two techniques in detecting bone marrow involvement in 35 consecutive patients with small cell lung cancer. The results were compared to those obtained with conventional cytohistological analysis. In all cases when cytology and/or bone marrow biopsy were positive, monoclonal antibodies immunostaining and magnetic resonance imaging also detected malignant cells. Furthermore, evidence of bone marrow involvement was shown with magnetic resonance imaging and/or immunostaining in 10 of 26 cases (38%) where routine procedures were unable to detect malignant cells. In one of these 26 patients, magnetic resonance imaging and immunostaining provided the only evidence of metastatic disease. These data suggest that the rate of bone marrow metastases is underestimated by routine procedures. Further investigation is needed to determine whether or not these new non-invasive methods have prognostic value or affect therapeutic choices in small cell lung carcinoma.

Antibodies, Monoclonal↗
PubMed1989

Immunomagnetic depletion of malignant cells from autologous bone marrow graft: from experimental models to clinical trials.

Using experimental modes with normal allogeneic bone marrow (BM) contaminated with Burkitt or neuroblastoma cell lines, and a liquid culture assay, we demonstrated that, when used in optimal conditions, the immunomagnetic depletion technique permitted a reproducible elimination of 3-4 log malignant cells. Results were very similar to those obtained with the complement lysis procedure in Burkitt lymphoma. This immunomagnetic procedure was used in 123 cases of autologous bone marrow transplantation (ABMT) in children with neuroblastoma. The analysis of the cases demonstrated, first, that the procedure induced a significant loss of mononuclear cells but was not toxic for BM precursors. Delays to engraftment observed in a few patients were probably due to the combination of pejorative factors, especially the damage caused to the micro-environment by previous heavy and prolonged chemotherapy or the double ABMT programme. Second, patients presented with profound T-cell defect with undetectable IL2 secretion up to 1 year post-graft but they all had normal NK functions from the first month post-graft, these functions exceeding normal values on the second and third months post-graft. Finally, in 20 cases, dual-immunofluorescence staining permitted the demonstration that the autograft contained malignant cells before purging that were eliminated by the immunomagnetic depletion.

Bone Marrow↗
PubMed1989

[Cytokines and their receptors networks: biology and therapeutic possibilities].

Cytokinins are biological proteins which permit the transmission of signals from one cell to another. These proteins are secreted by groups of specialized cells and are fixed on specific receptors on the surface of responding cells. However, since receptors may be widely distributed, and since the activation of a cell usually permits the release of other cytokinins and a succession of reactions, cytokinins have pleiotropic effects. Cloning of the genes encoding for these cytokinins and their obtention on a large scale by genetic recombination techniques have allowed a better understanding of their biological characteristics and their use in therapy. This cytokinin network is particularly wide in the hematopoietic and in the immune systems. In the present study, we describe the biological properties of the main interleukins and hematopoietic cell growth factors, together with their therapeutic applications, particularly in hemato-oncology.

Biological Factors↗
PubMed1989

Analysis of parameters for maximal in vitro proliferation and activation of lymphokine-activated killer cells (LAK).

In 15 patients (11 adults, 4 children) who received IL-2 and LAK cell therapy, we analyzed the different culture conditions which could either improve LAK cell activation and proliferation or which could simplify the procedure. Each parameter was assayed on a large scale and compared to standard culture conditions. Indomethacin had no effects, either positive or negative, on proliferation and activation of the cells. Culturing with 10% AB serum increased proliferation but did not modify total lytic activity compared to 2% AB serum. When cells were cultured in a medium with 2% autologous plasma obtained before any treatment, their proliferation was similar to that obtained in medium supplemented with 2% AB serum but the LAK activity was significantly higher. Autologous plasma obtained at day 8 of treatment (48 h after the first cycle of IL-2 and the day of the first cytapheresis) gave similar results to 2% AB serum. None of the 12 patients showed negative effects suggesting the presence of suppressive factors in the sera. Culturing with autologous plasma in clinical trials will lead to a 25% decrease in the total cost of culture and suppress the risk of viral contamination. Excess of granulocytes in the culture (greater than 30%), if the total nuclear cell concentration did not exceed 3 . 10(6) per ml, induced a better proliferation of mononuclear cells without modification of the activation. These results could be due to the liberation of factors by polynuclear cells, or to the loss during elimination of the granulocytes by the Ficoll separation of cells with similar density supporting LAK activity.

Adult↗
PubMed1988

S-L 11.14: a monoclonal antibody recognizing neuroectodermal tumors with possible value for bone marrow purging before autograft.

A new monoclonal antibody (S-L 11.14) raised against small cell lung cancer reacted with all but one neuroblastoma tumor cell sample tested and was relatively specific for such cells within the bone marrow. The ability of S-L 11.14 to eliminate neuroblastoma cells from the bone marrow with an immunomagnetic purging method was evaluated in an experimental model using the LAN.1 and SKNBE neuroblastoma cell lines as targets. Residual malignant cells after the purging procedure were quantified by the Hoechst staining method. The use of S-L 11.14 as a single reagent resulted in a 3-log elimination of malignant cells, a depletion equal to that obtained with a cocktail of five monoclonal antibodies currently used in clinical trials. The addition of the S-L 11.14 antibody to this cocktail did not enhance depletion.

Antibodies, Monoclonal↗
PubMed1988

[Value of immunological analysis for the detection of residual neuroblasts in the bone marrow].

Immunological analysis is complementary of morphological analyses in the detection of neuroblastoma BM metastases. It attests the neuroblastic nature of rare pseudolymphocytic isolated cells. The combination of immunocytochemical technique (alkaline phosphate) and double-immunofluorescence technique allows the detection of as few as 10(-5) residual neuroblastoma cells. At the time of bone marrow harvest, it permits a precise evaluation of malignant cells in the graft.

Bone Marrow↗