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Biomedical subjects

C Jasmin

Publications and source records attributed to C Jasmin.

At least 127 records · Page 7Linked to original sources

Prognostic value of blood and bone marrow T-colony-forming cells (T-CFC) in patients with lymphadenopathy syndrome (LAS).

The in vitro proliferation capacity of peripheral blood committed T-cell precursors (T-CFC) from LAS patients was studied in order to define whether this parameter could be associated with transition to AIDS. In all patients a significantly (P less than 0.0001) decreased plating efficiency was detected. However, the lowest T-cell colony growth (less than 50 colonies/5 x 10(4) cells) was observed in the 23 patients who subsequently developed the full-blown disease within 150-570 days. Conversely, only one patient (n = 107) whose T-CFC generated greater than 50 colonies/5 x 10(4) cells developed AIDS after a mean follow-up of 867 days (range 120-1260 days). T-CFC from these patients displayed an impaired in vitro differentiation and self-renewal capacity which was independent of the clinical evolution of the disease. In 5 out of 12 AIDS patients, adherent cell-depletion of peripheral blood mononuclear cells (PBMC) enhanced the plating efficiency. Moreover, patients' but not normal adherent cells could inhibit normal T-cell colony growth in a dose-dependent manner. Media conditioned by patients' unstimulated adherent cells (LCM-A+p) also inhibited normal T-cell colony formation. In addition, LCM-A+p were capable of inhibiting interleukin 2-receptor (IL 2-R) expression and interleukin 2 (IL 2) production by normal mitogen-stimulated T-cells. These findings suggest that adherent cell-derived inhibitory activity(ies) could be responsible for the low T-cell colony formation observed in some AIDS patients.

AIDS-Related Complex↗

Importance of age and methotrexate dosage: prognosis in children and young adults with high-grade osteosarcomas.

The disease-free survival (DFS) in 87 patients with high-grade non-metastatic osteosarcoma of the limbs treated in 3 consecutive pilot studies was compared. From 1978-1982 (Group 1), 41 patients were treated after surgery by adjuvant chemotherapy alternating 2 non-cross resistant cyclic combinations each month for 1 year and early prophylactic lung irradiation. From 1982-1984 (Group 2), preoperative chemotherapy 2-drug combination: adriamycin-cisplatinum (ADR-CDDP) was tested in 20 patients. Surgery was followed by 3 treatment periods of the same combination. From 1984-1987 (Group 3), 26 patients were treated according to modified T-10 protocol with high-dose methotrexate (HDMTX) adapted to age and individual pharmacokinetics. In Group 1, the overall 5 yr DFS was 63% (average follow-up 60.6 months). The worst prognostic factor was low age: 5 yr, DFS under 15 yr was 30%; greater than 15.5 yr, DFS was 85%. The second negative prognostic factor was failure to give sufficient MTX in patients greater than 15 yr. In Group 2, the actuarial 3 yr DFS was only 35% and a low age was still a negative prognostic factor. In Group 3, the 2 yr DFS was 90%, confirming Rosen's results. With HDMTX adapted to age and individual pharmacokinetics, age was no longer a negative prognostic factor. We concluded that HDMTX has a positive effect in the treatment of osteosarcomas in young people; furthermore, in very high doses, as determined by individual pharmacokinetics. In adults, postoperative chemotherapy eventually including moderate doses of MTX, can be effective and may be better tolerated.

Adolescent↗

Interleukin 2 responsiveness of immature T-cell colony-forming cells (T-CFC) from patients with acute T-cell lymphoblastic leukemias.

T-cell colony-forming cells (T-CFC) from 13 of 17 patients with T-ALL generated colonies in methylcellulose in the absence of added growth factors or mitogenic stimulation. As previously described, these colonies were composed of immature T cells displaying the same karyotypic abnormalities as fresh leukemic cells. Biochemically purified (bIL-2) and recombinant IL-2 (rIL-2) without any mitogen enhanced colony growth from both unfractionated and blast-enriched cell fractions in patients with a relatively low (less than 50 colonies/5 X 10(4) cells) plating efficiency. However, dose-response experiments revealed that the optimal dose of rIL-2 needed to enhance colony growth varied from patient to patient. Anti-IL-2 (DMS1) and anti-IL-2 receptor (anti-Tac) moAbs inhibited both spontaneous and rIL-2-induced colony formation in a dose-dependent manner. Direct staining of fresh leukemic cells with anti-Tac revealed less than 10% positive cells in all but two patients. However, cell incubation in the absence of growth factors or mitogens for 2-48 hr resulted in an increase of Tac+ cells. These observations indicate that a subset of immature T-CFC from T-ALL patients display functional IL-2-receptors. In addition, our findings strongly suggest that the IL-2/IL-2-R system could be involved in the spontaneous proliferation of some immature T-CFC of T-ALL patients.

Acute Disease↗

Peripheral blood adherent cells from AIDS patients inhibit normal T-colony growth through decreased expression of interleukin 2-receptors and production of interleukin 2.

Adherent cells display an important accessory role on normal T-cell colony formation. Since the in-vitro proliferation of T colony-forming cells (T-CFC) from AIDS patients is extremely impaired we studied the effect of patients' adherent cells on T-CFC growth. Patients' peripheral blood mononuclear cells (PBMC) were fractionated on the basis of rosette formation with sheep red blood cells and complement-mediated cytotoxicity with OKT3 monoclonal antibody (E-T3-). Both mature (E+) T cells and E-OKT3- cell fractions failed to generate T-cell colonies although colony growth could be obtained from unfractionated PBMC. In five out of 12 AIDS patients, adherent cell-depletion of PBMC enhanced the plating efficiency. Moreover, patients' but not normal adherent cells could inhibit normal T-cell colony growth in a dose-dependent manner. Media conditioned by patients' unstimulated adherent cells (LCM-A+p) also inhibit normal T-cell colony formation. In addition, LCM-A+p were capable of inhibiting interleukin 2-receptor (IL2-R) expression and interleukin 2 (IL2) production by normal mitogen-stimulated T cells. These LCM-A+p did not contain detectable reverse transcriptase activity nor could they infect the CEM T-cell line which is permissive to human immunodeficiency virus (HIV). Conversely, this adherent cell-derived inhibitory activity could be abrogated by heating or treatment with proteolytic enzymes. These findings indicate that the low T-cell colony formation in some AIDS patients could be due to adherent cell-derived inhibitory activity(ies).

Acquired Immunodeficiency Syndrome↗

Abnormal splenic megakaryopoiesis in MPSV-induced myeloproliferative disease.

The myeloproliferative sarcoma virus (MPSV) induces a murine myeloproliferative syndrome characterized by an erythromyelemia, an anemia, a thrombocytopenia associated with a myeloproliferation in the spleen and a splenic and medullar fibrosis. We have used the in-vitro plasma clot technique to measure megakaryocytic precursors in the spleen and bone-marrow of MPSV-infected mice. We report that megakaryocytic colonies are increased, in number (X75), in concentration (X9) and in size, in the spleen but not in the bone-marrow of neoplastic mice. Furthermore, these splenic precursors are hypersensitive to growth factors present in the anemic mouse serum used in the culture system. These data show that the thrombocytopenia observed in the MPSV-induced neoplasia does not result from a lack of megakaryocyte precursors, but rather from an excess of megakaryocyte destruction. This ineffective splenic megakaryopoiesis associated with the presence of a massive splenic fibrosis make the MPS-induced neoplasia a suitable model for studying the perturbation of megakaryopoiesis in myeloproliferative syndrome associated with fibrosis.

Animals↗

Abnormal proliferation of T-colony-forming cells from peripheral blood of patients with T-cell acute lymphoblastic leukaemias and lymphomas in complete remission: potential prognostic value.

Peripheral blood T-colony-forming cells (T-CFC) from most patients with T-cell acute lymphoblastic leukaemias (T-ALL) and T-cell non-Hodgkin's lymphomas (T-NHL), can proliferate in vitro in methylcellulose in the absence of added growth factors or mitogens. We now report that spontaneous T-cell colonies could also be obtained during complete remission of 13 out of 21 patients with T-ALL and T-NHL, but none of eight patients with common (pre-B) ALL (cALL). Colony cells were mainly E+T3+, with a variable expression of other T cell markers. Spontaneous T-CFC did not possess self-renewal capacity in the absence of added growth factors. Moreover, incubation of spontaneous colonies with colchicine yielded mitoses in only two out of seven patients, with one normal and one abnormal karyotype. In five patients tested, recombinant interleukin 2 (IL2) could also induce the proliferation of some T-CFC. Both spontaneous and IL2-induced colonies were inhibited by an anti-IL2 receptor monoclonal antibody, suggesting that interaction of IL2 with its receptor may be involved in the proliferation of some T-CFC from these patients. A study of 14 T-ALL patients tested during their first remission indicated that patients who developed no or few spontaneous colonies during their first remission (less than 20 colonies/10(5) mononuclear cells) seemed to relapse later and to have a significantly longer survival than patients with a high number of spontaneous colonies. These data suggest that the spontaneous proliferation capacity of T-CFC might be of prognostic value in the clinical evaluation of T-ALL.

Adolescent↗

Inhibition of rat natural killer cell function by carcinogenic nickel compounds: preventive action of manganese.

The effects of carcinogenic nickel [(Ni) CAS: 7440-02-0] and Ni compounds on the natural killer (NK) cell activity of rat peripheral blood mononuclear cells (PBMCs) were studied. Rhabdomyosarcomas were locally induced by one im injection of Ni or Ni subsulfide [(Ni3S2) CAS: 12035-72-2] dust in the hind leg of WAG rats. A weakly tumorigenic dose of 5 mg Ni3S2 (tumor incidence, 2%) induced a transient decrease of PBMC NK activity against YAC-1 cells in vitro (from the 17th to the 23d wk after Ni3S2 inoculation), which could be restored by in vivo injections of partially purified rat fibroblastic interferon (IFN). Injection of 20 mg Ni (tumor incidence, 47.5%) produced a long-lasting depression of NK cell activity (from the 8th to the 23d wk). In vivo chronic IFN treatment of the Ni-injected rats neither restored NK cell activity nor affected the tumor incidence. However, NK cells of Ni-treated animals responded normally to IFN in vitro. Prospective analysis of individual NK cell responses showed that a persistent depression of basal NK cell activity was restricted to rats that subsequently developed a tumor. In these animals the time between carcinogen treatment and clinical detection of the primary tumor was positively correlated with the mean level of NK cell activity (3-4 determinations/rat). Admixture of manganese to Ni inhibited the development of tumors and also prevented the depression of NK cell activity produced by Ni alone. Noncarcinogenic Ni oxide stimulated NK cell activity. These results point out the possible involvement of NK cells in resistance to Ni-induced carcinogenesis.

Animals↗

Characterization of interleukin-2 receptors expressed on acute leukemic B cells.

More than 90% of both unfractionated and blast-enriched T cell-depleted mononuclear cells (MNC) from a patient with a morphologically and phenotypically unclassified acute leukemia expressed interleukin 2 receptors (IL2-R), whereas 50% unfractionated MNC displayed monocyte/myeloid- (My7, My9, and OKM1) and B cell-restricted (B4) antigens. Two-color fluorescence studies showed that 80% of the My9+ cells expressed the B4 antigen and 63% of the B4+ cells were IL2-R+. Cell incubation with phorbol myristate acetate (PMA) increased the expression of B4 antigen and significantly decreased the proportion of My9+ and IL2-R-bearing cells. Southern analysis of DNA from leukemic cells revealed monoclonal rearranged heavy and k light-chain immunoglobulin genes. Immunoprecipitation of leukemic cell membrane proteins with a monoclonal antibody recognizing the IL2-R (anti-Tac) revealed a protein with the same molecular weight (55 kilodaltons) as that of the IL2-R present on PHA-stimulated normal T cells. Fresh leukemic cells did not express high-affinity IL2-R and did not proliferate in liquid culture or in a colony assay in the presence of recombinant IL2 (rIL2). PMA-treated blast cells, however, generated B cell colonies in the presence of rIL2, thus suggesting that PMA could induce functional IL2-R on immature leukemic B cells.

Acute Disease↗

AIDS and lymphadenopathy syndrome (LAS) patients display similar abnormal in vitro proliferation and differentiation of T-colony forming cells (T-CFC).

T-cell colonies were generated from the peripheral blood and bone marrow of 61 patients with acquired immunodeficiency syndrome (AIDS), 54 patients with persistent lymphadenopathy syndrome (LAS), 14 clinically normal male homosexuals, and 17 healthy heterosexuals. Mononuclear cells were cultured in methylcellulose in the presence of IL2-containing conditioned medium. The number of T-cell forming cells (T-CFC) from healthy male homosexuals and AIDS and LAS patients was significantly (P less than 0.01) reduced compared to T-CFC from healthy heterosexuals. In AIDS patients, the low colony growth capacity of T-CFC was independent of the presence of either opportunistic infections or Kaposi sarcoma. Twelve LAS patients who subsequently developed AIDS showed the lowest capacity of peripheral blood and bone marrow T-CFC to proliferate. Pooled induced colonies from AIDS and LAS patients and normal homosexuals were composed of immature cells bearing the T3+, T4+, T6+, and T8+ surface phenotype, unlike colonies from normal heterosexuals, which displayed mature cells bearing the T3+, T4+, T6-, and T3+, T8+, T6- surface phenotype. Moreover, most T-CFC from primary colonies had lost their self-renewal capacity. In some AIDS and LAS patients but not healthy homosexuals peripheral blood and bone marrow T-CFC were capable of generating colonies with recombinant IL2 (rIL2) without any other mitogenic stimulation. The rIL2-induced colony growth was abrogated by a monoclonal antibody against the IL2 receptor. These results suggest that early impairment of T-CFC plays a predominant role in the pathogenesis of AIDS.

AIDS-Related Complex↗

Media conditioned by human leukemic T-cells induce expression of IL2 receptors and proliferation of normal T lymphocytes.

Peripheral blood T-colony-forming cells (T-CFC) from patients with T-cell acute lymphoblastic leukemias (T-ALL) and T-cell non-Hodgkin lymphomas (T-NHL) can generate colonies in methylcellulose in the absence of added growth factors and/or mitogenic stimulation. In the present study, we show that media conditioned (LCM) by unstimulated mononuclear cells (MNC) from these patients can induce proliferation (proliferating inducing activity; PIA) and promote colony growth (T-cell colony promoting activity; T-CPA) of normal T lymphocytes in the absence of any other mitogenic stimulation. Preincubation of normal E+ lymphocytes with some TCPA+, PIA(-)-LCM for 48 hr leads to IL2-induced cell proliferation in the absence of any other stimulation. Moreover, staining of the cells with anti-Tac monoclonal antibody (Mab) reveal 9%-26% Tac+ cells. Both PIA and IL2 receptor-inducing activities were abrogated by treatment of LCM with proteolytic enzymes or by heating at 47 degrees C for 30 min. Modulation of the T3 molecule by OKT3 MAb on normal E+ cells did not abrogate the capacity of LCM to induce expression of IL2-receptors, suggesting that this activity was not mediated by triggering the Ti-T3 molecular complex. These activities were detected in media conditioned by both unfractionated MNC and blast-enriched cell fractions, and their production required DNA and RNA synthesis by actively dividing cells. Taken together, these findings indicate that human leukemic T cells spontaneously release activities which can activate normal resting T lymphocytes.

Antibodies, Monoclonal↗

T-cell colony formation in patients with T-cell malignancies: growth factor requirements for in-vitro proliferation of peripheral blood T-cell colony-forming cells.

Peripheral blood T colony-forming cells (T-CFC) from patients with T-cell malignancies are capable of proliferation in methylcellulose, in the absence of added growth factors or mitogenic stimulation. We show here that based on the spontaneous plating efficiencies of their T-CFC, two groups of patients can be established: Group A (10 patients) with a high colony number (more than 100 colonies/10(5) seeded cells), and group B (12 patients) with less than 100 colonies/10(5) cells. The addition of interleukin 2-(IL2) containing PHA-leukocyte conditioned medium enhanced colony growth from group B but not group A patients. Moreover, both biochemically purified and recombinant IL2 induced the colony growth from group B but not group A patients without any other stimulation. In addition, a monoclonal antibody (moAb) against the IL2 receptor (IL2-R; anti-Tac) inhibited the spontaneous colony formation from T-CFC of both groups of patients. These observations strongly suggest that IL2-R are involved in the spontaneous colony growth of T-CFC. To determine whether IL2 is also involved in the spontaneous colony formation, media conditioned (LCM) by unstimulated leukemic cells were tested for IL2 activity. A constitutive release of IL2 was detected in LCM from only 2 out of 10 patients tested, and some of them were capable to inhibit thymidine incorporation by IL2-dependent cells cultured in the presence of highly purified IL2. However, most of these LCM contained a T-cell colony-promoting activity (TCPA) inducing colony formation from both normal resting and PHA-stimulated E+ clonogenic cells without added IL2 or mitogenic stimulation. TCPA-containing LCM induced the expression of functional IL2-R and IL2 release by normal resting lymphocytes. TCPA was constitutively released by blast-enriched cell fractions suggesting that it is released by the leukemic cells.

Antibodies, Monoclonal↗

Isolation from the spleen of myeloproliferative sarcoma virus-infected mice of a myelomonocytic tumor cell line secreting hematopoietic colony stimulating factors.

Clonogenic tumor cells were detected in the spleen of DBA/2 mice infected with the myeloproliferative sarcoma virus (MPSV). These cells could be isolated because of their ability to proliferate on the greater omentum of sublethally irradiated isogenic recipient mice. We have established a permanent suspension myelomonocytic cell line in vitro (TE8), from a tumor obtained after subcutaneous transplantation of the omental tumor masses. The TE8 cells are clonogenic in semi-solid medium containing agarose. The colonies thus obtained gave rise to myelomonocytic cell lines growing in suspension in liquid medium. One of those cloned cell lines, C1(1011) was studied in details. It is exclusively composed of initial donor cells, it is tumorigenic in vivo, clonogenic in vitro and produces MPSV. It also secretes a colony stimulating activity (CSA), and an activity termed mixed colony promoting activity (MPA), which enables pluripotent hematopoietic stem cells to proliferate and differentiate. It differentiates through the granulomacrophage cell line independently of exogenous factors other than those which may be present in the serum.

Animals↗

[Tumor stem cells and implications for the immunotherapy of cancer].

Passive, active and adoptive immunotherapy of human cancers and leukemias raise a renewed interest strengthened by the availability of purified biological substances such as IL2, interferon, thymic hormones and by some recent favourable therapeutic results which have demonstrated the possibility of obtaining objective tumor regressions by immunotherapy. Analysis of results of chemotherapy shows that only 8 human cancers and malignant hemopathies are curable at an advanced diffuse stage of disease. These cancers are characterized by the rarity or absence of late metastases (more than 3-4 years after initial diagnosis). Cure may be considered as complete with a high probability if disease free status is maintained for 3 years. This finding suggests the absence of tumor stem cells capable to produce late metastases. Other cancers are not chemocurable at an advanced systemic stage. In most of them late metastases (greater than 4 years after diagnosis) are observed. A model of organization of malignant tumors based on the distinction between primitive tumor stem cells which are rarely or exceptionally in cycle and protected by a specific microenvironment and committed tumor stem cells is proposed. According to this model, only cancers and/or metastases and malignant hemopathies containing but committed tumor stem cells would be chemocurable. Analysis of a trial of adjuvant therapy of breast cancer with poly A: poly U shows the possibility of immunotherapy to prevent the development of late metastases, independently of hormonal status in contrast with standard adjuvant chemotherapy which is only active on early micrometastases in premenopausal women.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗

CNS-side effects induced by Ifosfamide-Mesna in children with osteosarcomas.

The authors have had the opportunity to see two cases of CNS side effects of Ifosfamide-Mesna association in children. Data in the medical literature about this subject remains poor. Only a few observations are available. In the referred cases, CNS side effects (lethargy, apathy and mutism) appeared a few hours after the second day of treatment and were spontaneously reversible in a few days. After reviewing possible mechanisms of this toxicity the authors pointed out the necessity to keep this type of side effects of Ifosfamide-Mesna association in mind, and to avoid it in susceptible patients.

Adolescent↗