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Biomedical subjects

G Mathé

Publications and source records attributed to G Mathé.

At least 163 records · Page 9Linked to original sources

Effects of three new nitrosourea analogs (CNCC, RFCNU and chlorozotocin) on in vivo destruction of L 1210 leukemia cells and on the immune response.

Three new nitrosourea analogs (CNCC, RFCNU, and chlorozotocin) had comparable activities in vivo against L1210 leukemia cells. In addition to the antileukemia effect, these drugs also decreased both the humoral immune response to sheep red blood cells and the delayed hypersensitivity reaction to oxazolone. The immunodepression induced by these agents lasted at least 25 days, and could not be reversed by the transplantation of normal syngenic bone marrow cells into treated animals.

Animals↗

Enhancement of NK-cell activity in normal and tumor-bearing mice after administration of aclacinomycin.

Aclacinomycin (ACM) a new cytotoxic antibiotic employed in cancer chemotherapy, can either enhance or inhibit the NK-cell activity of the immune system, depending on the dose administered. A single intraperitoneal injection of 2-4 mg/kg of ACM augments the cytolytic activity by spleen and peritoneal exudate cells of normal mice and spleen cells depleted of nylon-adherent cells and peritoneal exudate cells of tumor-bearing mice. In contrast to the stimulatory effect of NK-cell activity by low doses of ACM, a single injection of 8 mg/kg of this agent leads to depression in the level of NK-cell activity in both normal and tumor-bearing animals. We suggest that the mechanism through which the ACM enhances NK-cell activity may be through the deletion of a suppressor cell population acting on the NK cells.

Aclarubicin↗

Interindividual differences in the circadian hematologic time structure of cancer patients.

The complete hematologic blood cell count of 11 patients with advanced cancer were determined on 14 occasions, every 4 hr over 36-48 hr. Oral temperature was also measured at the same times as blood sampling. Five patients had breast cancer, five had ovarian cancer and one a leiomyosarcoma. Circadian rhythms were detected by the cosinor method for seven hematologic variables (red blood cells, hemoglobin, hematocrit, white blood cells, neutrophils, lymphocytes, platelets) and for oral temperature in the whole group of patients. All acrophases were located between 1300 and 1700 hr, except for lymphocytes (2100 hr). A rhythm with a period of 8 hr was validated for lymphocytes and monocytes. Validated or estimated amplitudes and acrophases were closely similar in both breast and ovarian cancer subgroups. Individual cosinor analyses documented large differences from patient to patient, which were accounted for by differences in performance status. Thus, subjects with poor performance status and rapidly progressive disease had very few validated rhythms as compared to those patients with good performance status. As a result a statistically significant correlation was found between the number of validated hematologic circadian rhythms and the performance status (r = -0.88; P less than 0.01).

Adult↗

In vivo immunopharmacological properties of tuftsin (Thr-Lys-Pro-Arg) and some analogues.

Tuftsin (Thr-Lys-Pro-Arg) is part of the Fc fragment of a leukophilic IgG and is a stimulator of the phagocytic activity of macrophages and polymorphonuclear cells (PMN) when cleaved from its carrier molecule. Tuftsin was shown to stimulate in vitro all PMN and macrophage functions examined through binding to specific cell surface receptors. In the present work, we provide further evidence that synthetic tuftsin administered to mice may act as an immunomodulator and that its effects on immune functions may result from a primary action on macrophages. After i.v. injection at a dosage of 25 micrograms/mouse, tuftsin stimulated effector (phagocytosis) and regulatory (IL1 production) functions of macrophages and potentiated DTH reaction. Lymphocyte functions (proliferative response to mitogens, T cell-mediated cytotoxicity, IL2 and gamma IFN production) were depressed at times at which macrophage activities were maximally enhanced, suggesting that negative regulatory functions of these latter cells were also stimulated. Tuftsin analogues were synthetized representing substitution or derivatization of the threonyl residue. The relative potencies of these analogues in augmenting phagocytosis-induced chemiluminescence of macrophages were tuftsin greater than or equal to (Gly1)-tuftsin greater than for-tuftsin greater than (for-Met1)-tuftsin greater than (Met1)-tuftsin. Concerning potentiation of DTH reaction the order was (Gly1)-tuftsin greater than or equal to (for-Met1)tuftsin greater than tuftsin greater than (Met1)-tuftsin greater than for-tuftsin. In contrast to tuftsin, none of the analogues induced depression of spleen cell reactivity to mitogens. In addition, (for Met1)-tuftsin administration resulted in an increased production of IL2 and IFN by ConA-stimulated spleen cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗

T lymphocytic subpopulations of normal human peripheral blood defined by monoclonal antibodies: an ultrastructural study using immunogold staining method.

Submicroscopic findings of T lymphocytic subpopulations of normal human peripheral blood defined by OKT monoclonal antibodies were studied using ultrastructural immunocytochemistry (immunogold staining). The results show that OKT4-and OKT8-positive lymphocytic subpopulations have a distinct morphological pattern, although some variations in the ultrastructural details of cells in each subset are evident. The most representative features of OKT8-positive cells are regular or slightly indented nucleus with condensed chromatin, abundant cytoplasm, prominent Golgi apparatus, several granules frequently localized in the Golgi area, and numerous mitochondria, often in cluster disposition. OKT4-positive cells show generally less condensed chromatin, scanty cytoplasm and poor organule pattern. Furthermore, positive lymphocytes with prominent nuclear irregularities are found in both lymphocytic subpopulations. Ultrastructural similarities between the T cell subsets phenotypically characterized by monoclonal antibodies and other immunological criteria are also discussed.

Antibodies, Monoclonal↗

[Advanced cancer of the prostate. Treatment with an LH-RH agonist, D-Trp-6-LH-RH].

D-Trp-6-LH-RH, a long acting LH-RH agonist was given in a phase II trial to 85 patients aged 52 to 88 (mean 69) with advanced prostatic carcinoma, stage B (8 pts), C (9 pts) and D (68 pts). Twenty-five patients were previously untreated, 40 had received previous hormonal therapy but none was considered has having hormone resistant tumor; 20 patients had received surgery or radiotherapy or both. D-Trp-6-LH-RH was given s.c. at a daily dose of 500 micrograms during the first seven days, followed by 100 micrograms daily. Antitumor activity was assessed after 90 days and treatment was continued in responders. The results were the following: plasmatic levels of LH were sharply decreased and those of testosterone were in all cases under 1 ng/ml by the 90th day of treatment; urinary symptoms and bone pain disappeared or were greatly improved in almost all patients; the volume of the prostate measured by ultrasonography and/or computerized tomography regressed by more than 50% of initial volume in 44% of the 34 patients for which this parameter was evaluable; bone scintiscans were improved in 18% of evaluable patients; plasmatic levels of prostatic acid phosphatases determined by radio immuno-assay were elevated in 28 patients, 61% of which presented a decrease superior to 50% or normalisation of this parameter. No disease flare up was observed on initiation of therapy. Impotence was constant but reversible on discontinuation of therapy. No other side effect could be attributed to therapy.

Acid Phosphatase↗

Human thymocyte differentiation: an ultrastructural study using monoclonal antibodies and immunogold staining method.

The ultrastructural features of normal human thymocytes were analyzed at various stages of immunologic differentiation as defined by a panel of OKT monoclonal antibodies visualized by colloidal gold labelled antimouse IgG. The study shows that first stage thymocytes (OKT10+, OKT9+) have a typical morphology not found in more mature stages and describes the critical ultrastructural change which they undergo in becoming second stage thymocytes (OKT10+, OKT6+, OKT8+, OKT4+). No change in thymocyte fine morphology has been found in the progression from second to third stage (OKT10+, OKT3+, OKT8+ or OKT10+, OKT3+, OKT4+). Cells with ultrastructural features intermediate between those of the first and second stage have been found to react with monoclonal antibodies characterizing the first and the second stage. Ultrastructural similarity and homogeneity found in OKT8+ and OKT4+ thymic subpopulations suggests the acquisition by T lymphocytes of morphologic structures correlate with immunologic features previously found in peripheral blood T cell subpopulations to be a post-thymic process.

Antibodies, Monoclonal↗

[Circadian and seasonal changes of the inducer:suppressor ratio (OKT4+:OKT8+) in venous blood of healthy adults].

Circadian and seasonal variations in the T helper: T suppressor-cytotoxic ratio were investigated in peripheral blood from five healthy young men. Mononuclear cells were isolated on Ficoll-Paque gradient, then incubated with OKT4 and OKT8 monoclonal antibodies. Plasma cortisol was determined in four of these seven time series. Large interindividual differences were documented and statistically validated for the 24-hr.-means of total lymphocytes, OKT4+:OKT8+ ratio, and of plasma cortisol (both total and free). For a pooled data, a circadian rhythm was demonstrated by cosinor (p less than 0.001) for total lymphocytes (acrophase at 1.00 hr.), total plasma cortisol (acrophase at 10.30 hrs.) and free plasma cortisol (acrophase at 9.50 hrs.), but not for OKT4+:OKT8+ ratio. This index however exhibited a statistically significant circadian rhythm in April and August, but not in November. Its double-amplitude exceeded 80% of the 24-hour-mean and its acrophase was localized at 6.40 hrs. in April and at 22.30 hrs. in August. Its 24-hr-mean was higher in August as compared to April and November. The circadian rhythm in the OKT4+:OKT8+ ratio did not seem to be related to that of plasma cortisol. Both circadian and seasonal variations need to be taken into account when investigating the regulations of immune variables such as T helper: T suppressor-cytotoxic ratio.

Adult↗

Abnormal in vitro differentiation of peripheral blood clonogenic B cells in common acute lymphoblastic leukemia during complete remission.

An in vitro B cell colony assay system was used to evaluate B cell growth from peripheral blood precursors in common acute lymphoblastic leukemia (CALL) patients in remission during maintenance therapy and in normal controls. Major differences between the two groups were found in the phenotypic and morphologic features of pooled colony cells. In both cases, the cells were E-. Controls' cells were surface immunoglobulin (sIg)-positive, and some (mean, 25%) expressed la determinants. By Wright-Giemsa staining, they appeared as plasmacytoid cells. In contrast, patients' cells had predominantly a lymphoblastoid appearance, fewer cells had developed sIg, and a large fraction (mean, 43%) were Ia-positive. Moreover, the CALL antigen (CALLA) was expressed by a mean of 18% (range, 2% to 72%) of the patients' colony cells, whereas CALLA was never found in control colonies. Thus, cells with immature features persist in the colonies of CALL patients. Secondary colonies could be generated from the patients' cultured cells, indicating their self-renewal capacity. CALLA + cells were also present in the secondary colonies. Finally, cytogenetic studies showed that a fraction of the patients' colony cells had karyotypic abnormalities similar to that of the original lymphoblasts. It is believed that in CALL patients this B cell assay permits the clonal expansion of residual circulating cells linked to malignant clones that are not detectable by classic hematologic and cytologic methods.

Adolescent↗

Leukopenic chronic T cell leukemia mimicking hairy cell leukemia: association with human retroviruses.

We report two cases of a T cell lymphoproliferative disease not previously described, with cytologic and clinical features similar to those associated with Galton's "prolymphocytic" leukemia (PL). Our patients, like those with Galton's PL, had massive splenomegaly and minimal or absent hepatomegaly and lymphadenopathy. In contrast, however, our patients had leukopenia, as well as low percentages of leukemic cells in the peripheral blood and in the bone marrow. In splenic imprints, the nuclear chromatin pattern of most of the leukemic cells was intermediate between those of mature lymphocytes and those of lymphoblasts, and the nuclei contained single, centrally located, conspicuous nucleoli. In sections of the spleen, the leukemic cells diffusely infiltrated the red pulp in a pattern strikingly similar to that of hairy cell leukemia; however, when the leukemic cells were studied cytochemically, the cytoplasmic acid phosphatase positivity was punctate and tartrate-sensitive. The leukemic cells were sheep erythrocyte rosette-positive and expressed T cell-associated antigens. Initially, both patients responded well to therapeutic splenectomy. One patient received combination chemotherapy after splenectomy and is alive and well 24 months after diagnosis. The other patient was in complete clinical remission for one year after splenectomy and received chemotherapy at relapse. He died, however, 23 months after splenectomy, with disseminated disease. IgG antibody titers against human T lymphotropic virus type I (HTLV-I) were detected in one patient and against HTLV-II in the other. The leukemia in these patients represents a distinct clinicopathologic entity within the spectrum of peripheral T cell lymphoproliferative diseases that includes Galton's PL of T cell derivation, T cell chronic lymphocytic leukemia, T cell hairy cell leukemia, and adult T cell leukemia/lymphoma.

Adult↗

[Experiences and perspectives on adjuvant chemotherapy in osteogenic osteosarcoma].

This article analyses the relevance of the published results of adjuvant chemotherapy in osteogenic osteosarcomas. It discusses the causation and prospects for treatment particularly the details of the chemotherapy, with reference to mono- or poly-chemotherapy, the influence of the dose and of the interval of administration, and also the value of pre- and post-operative chemotherapy. It is apparent that intensive pre-operative chemotherapy limited to 4 weeks is a reasonable mean of distinguishing the good responders. The problem of the choice of therapy for bad responders is also discussed.

Antineoplastic Combined Chemotherapy Protocols↗

A monoclonal antibody reactive with human eosinophils.

EO-1, an IgGl murine monoclonal antibody raised against human eosinophilic leukemia cells, reacts with eosinophils, basophils, platelets, and a few (2%) mononuclear cells but not with neutrophils. In the bone marrow, mature and immature eosinophils and basophils express the EO-1 antigen, whereas immature myeloid cells do not. The distribution of EO-1 antigen on leukemic cells is concordant with this finding, ie, typical myeloid lines (HL-60, KG-1, and ML-1) and fresh acute myelogenous leukemia cells are all unreactive with EO-1. Immunoprecipitation of an extract from surface-131I-labeled platelets with EO-1 and sodium dodecyl sulfate polyacrylamide gel electrophoresis, under reducing or nonreducing conditions, yielded a specific band of molecular weight 23,000. Previously described monoclonal antibodies reacting with eosinophils also recognize neutrophils. EO-1 is a unique antibody with specificity restricted to eosinophils, basophils, and platelets and might therefore be a valuable reagent for the study of their function and differentiation.

Animals↗

Excess of lympho-reticular cell complexes in the bone marrow linked to T cell mediated dysmyelopoiesis.

The term dysmyelopoietic syndrome (DMPS) covers a variety of closely related disorders with various etiological factors, and characterized by chronic (pan) cytopenias whose prognosis and treatment are still controversial. Despite the recent efforts to identify pathogens, effector cells and soluble cell products involved in the development of this syndrome only a few comprehensive experimental data are available, useful for elaboration of therapeutic regimens. We describe here a patient with DMPS who was refractory to inductive chemotherapy. Initial agar gel culture studies revealed the activity of hematopoiesis inhibitory T cells within the bone marrow that could be suppressed by prednisone both in vitro and in vivo. However another pathological cell features, the excess of an unusual lympho-reticular cell complexes was identified in long-term liquid cultures. These symbiotic cell complexes persisted throughout the disease, despite the prednisone induced hematological remission, suggesting their causative role in the disease, that more recently progressed towards acute myeloid leukemia.

Adult↗

Immunomodulating properties of bestatin in cancer patients. A phase II trial.

Thirty-four patients with cancer (30) or ARC (4) with severe T cell defect or imbalance persisting a long time after completion of any cytostatic treatment were treated by bestatin 30 mg/day 3 days per week during three weeks. The drug has no toxicity of any kind. Reassessment of T cell subsets after completion of bestatin therapy showed a significant improvement of the absolute number of CD4 cells in peripheral blood. CD8 subsets wether initially increased or decreased were modified towards normalisation but the modification reached statistical significance only in the subgroup with initial absolute defect of CD8 cells. CD4/CD8 ratio was significantly increased whether considering all cycles of therapy, or all those given to patients with initially high or normal CD8 subsets. Bestatin appears to have immunomodulating properties which might be useful in cancer patients.

Adjuvants, Immunologic↗

A phase II trial of immunorestoration with zinc gluconate in immunodepressed cancer patients.

Zinc is an trace metal necessary for T cell differentiation and maturation. Forty-two patients, with Aids Related Complex or malignancy in remission and with severe and stable CD4 lymphoid cells cytopenia were submitted to zinc gluconate, 125 mg twice daily orally for three weeks. Reevaluation of T cell subsets one week after the end of zinc intake showed non significant modification of total lymphocyte counts nor of CD4 subsets. CD8 cells however were significantly increased in absolute number in those patients with initially low counts of the cells while they were significantly reduced in those patients with initially normal or high CD8 cells counts. Zinc gluconate in short courses appear to act as a regulator of CD8 lymphoid cells subsets.

AIDS-Related Complex↗