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N Odartchenko

Publications and source records attributed to N Odartchenko.

At least 37 records · Page 2Linked to original sources
PubMed1986

[Comparative prognostic study of the in vitro and in vivo development of colorectal tumors. Preliminary communication].

In vitro clonal growth of tumour cells may reflect biological properties of cancer and thus have prognostic value. This study seeks to establish correlations between the clinical outcome in patients after surgery for colorectal cancer and clonal growth of their tumours. History, status and follow-up data are collected. Tumour samples taken at operation under sterile conditions are plated immediately in our methylcellulose clonal assay system. Out of 65 consecutive samples, 3 did not yield sufficient cells for culture. Thirty-four (55%) grew more than 0.3 colonies/10(5) cells seeded; cloning efficiency was greater than 10 colonies/10(5) cells in 19. The 28 (45%) failures included 3 benign polyps cultured; 7 samples had visible bacterial or fungal contamination. The other 18 negative cultures may be due to cytotoxicity of the antibiotics or heterogeneity of tumour cells. These preliminary results show that colorectal cancers grow well in vitro in the absence of restricting factors, but they do not confirm the hypothesis that proliferative potential and differentiation are opposing processes. Location of the tumour may play a role, since best growth was seen in tumours of the caecum and terminal colon.

Cell Division↗
PubMed1985

Colony formation by primitive hemopoietic progenitor cells in serum-free medium.

A serum-free medium has been developed for clonal growth of murine hemopoietic progenitor cells. In this medium, the number of nonerythroid colonies induced by factors produced by cloned T lymphocytes was 90 +/- 10% of the number generated in serum-containing medium. Erythroid colony number in serum-free cultures containing the T-cell factors but no exogenous erythropoietin was significantly higher than that in cultures with serum, and the cloning efficiency was independent of cell concentration. Further addition of erythropoietin increased erythroid colony number approximately equal to 4-fold. Pure erythropoietin alone stimulated erythroid colony formation, but the cloning efficiency was highly dependent on cell concentration. Analysis of individual colonies generated in serum-free cultures containing the T-cell factors indicated that some contained cells of several hemopoietic lineages, demonstrating that multipotential progenitors can give rise to colonies in this system.

Animals↗
PubMed1985

Early hemopoietic progenitor cells: direct measurement of cell cycle status.

We have investigated the cell cycle status of murine hemopoietic progenitors using vital DNA staining and flow sorting. Suspended Balb/c bone marrow cells were stained with Hoechst 33342 dye and separated first on light scattering properties; this procedure allowed a 5-fold enrichment in progenitor cells. A second sorting based on DNA content indicated that 80% of these cells were in G0/G1 and 20% in S-G2 + M. When G0/G1 and S-G2 + M cells were assayed separately in methylcellulose cultures, or with the in vivo colony forming assay, the G0/G1 cells were shown to be markedly enriched in CFU-S, BFU-E, and GM-CFU as compared to S-G2 + M cells with the final recovery increased 20-fold. Comparison of different strains or age groups yielded results identical to those obtained with Balb/c with the exception of C57B1/6. In the latter strain only a 3-fold enrichment could be observed in the G0/G1 fraction. These results demonstrate that the majority of early hemopoietic progenitors are in the G0/G1 phase of the cell cycle.

Animals↗
PubMed1984

Improving techniques for clonogenic assays.

A serum-free medium has been developed which supports colony formation by cells from several human tumor cell lines, one colon adenocarcinoma (WiDr) and four melanoma (Me43, Me85, MP6, MeIuso). This medium consists of a 1:1 mixture of an enriched Dulbecco's modified Eagle's medium (EMED) and a modified Ham's F-12 nutrient mixture (FMED) supplemented with 0.9% methylcellulose, 1% bovine serum albumin, 80 micrograms/ml human transferrin, 3 micrograms/ml insulin, 2.8 micrograms/ml linoleic acid, 2.6 micrograms/ml cholesterol, 20 microM ethanolamine, and trace elements. Colony formation by WiDr cells is linear with the numbers of cells plated, having a plating efficiency (PE) of 34%, as compared to 26% in serum-containing medium. Two of the melanoma cell lines. MP6 and MeIuso, exhibit linear relationships between colony numbers and cell concentration with PEs of 21% and 70% respectively. Colony formation by the other two melanoma cell lines appears to be nonlinear. This work represents a step toward standardizing culture conditions for human tumor clonogenic cell assays.

Adenocarcinoma↗
PubMed1983

Macromolecules stimulating human granulocytic colony-forming cells, precursors of these cells, and primitive erythroid progenitors: some apparent nonidentities.

The relationship between molecules having granulocyte colony-stimulating activity (G-CSA), erythroid burst-promoting activity (E-BPA), and activity promoting increase in the number of granulocytic progenitors in liquid culture (delta GPA) was explored in conditioned medium from human leukocytes (HLCM) and human placenta (HPCM). As tested on human hemopoietic progenitors in culture, G-CSA eluted from Sephadex G100 as a single peak with apparent molecular weight of 25,000, separating partially from E-BPA and delta GPA, which both had an apparent molecular weight of 45,000. All three activities eluted together from hydroxyapatite at low molarity phosphate. Their charge properties were also similar and all three electrofocused in flat gel beds in the pH range near 5.4. On both hydroxyapatite and isoelectric focusing, delta GPA sometimes separated partially from the other two activities but not consistently. The gel filtration result shows that in conditioned medium of human origin, molecules having G-CSA are not the same as those having delta GPA, suggesting a dual factor requirement in the granulocytic lineage reminiscent of that in the erythroid pathway. The results suggesting that delta GPA might differ from E-BPA, on the other hand, were not consistent enough to establish their nonidentity. Single micromanipulated cells proved capable of forming erythroid or granulocytic colonies in the presence of either crude or partially purified activity. The results establish that human colony-forming cells are direct primary targets of growth factors in HLCM and HPCM.

Chromatography↗
PubMed1981

Agar extract induces release of granulocyte colony-stimulating activity from human peripheral leukocytes.

Water-soluble components of crude bacto-agar are known to be mitogenic for mouse B lymphocytes. We examined the effects of aqueous agar extract in liquid cultures of human peripheral leukocytes. In comparison with phytohemagglutinin (PHA), agar extract had only weak mitogenic activity. However, it was almost as effective as PHA in promoting the release of granulocyte colony-stimulating activity (G-CSA) into the supernatant medium. This activity was assayed in methyl cellulose cultures of non-plastic-adherent human bone marrow cells. The results provide information on the mechanism of G-CSA release in cultures of agar-immobilized human leukocytes, and serve as a reminder that crude agar is not a completely inert culture constituent.

Agar↗
PubMed1977

[Post-partum survival of fetal lymphocytes in the maternal blood].

Cells of fetal origin have been searched for in the peripheral blood of mothers following delivery of a boy, using mepacrine fluorescence of the Y chromosome. In a series of 62 women such cells have been found for approximately two years in more than half of cases. Their number decreases thereafter but in some instances Y chromosome-bearing cells have been observed 5 years after delivery.

Cell Survival↗
PubMed1975

[Characterization of megakaryocyte colonies in vitro].

Agar cultures of mouse bone marrow cells can be stimulated by medium conditioned by activated mouse lymphoid cells to produce pure or mixed colonies containing up to 80 megakaryocytes. These have been characterized on the basis of their morphology, polyploid mitoses and DNA content and high cytoplasmic content of acetylcholinesterase.

Acetylcholinesterase↗
PubMed1975

Kinetic studies on glial, Schwann and capsular cells labelled with [3H] thymidine in cerebrospinal tissue of young mice.

Neuroglia, capsular and Schwann cell renewal and turnover in the cerebellum, the spinal cord and spinal ganglia have been evaluated in 2-months-old mice. The animals received intraperitoneal injections of [3H] thymidine at 8 hr intervals starting on the 28th day of postnatal life for a period of 30 days and were killed 1 hr after the last injection. Substantial numbers of labelled neuroglial cells but no labelled neurons were observed. Oligodendrocytes of the cerebellum and the spinal cord showed higher labelling indices (19.8% and 18.0%, respectively) than astrocytes (10.0%) and Bergmann's supporting cells (7.2%). The labelling indices of capsular cells in the spinal ganglia and Schwann cells in the spinal roots were 35.8% and 25.8%, respectively. The experiments failed to provide evidence for matrix cell layers in the cerebellum, the spinal cord and spinal ganglia. It may be concluded therefore that glial and Schwann cells in these parts of the nervous system proliferate in situ.

Animals↗
PubMed1975

Growth of mouse megakaryocyte colonies in vitro.

Mouse bone marrow and spleen cells formed pure or mixed colonies of up to 80 megakaryocytes in agar cultures after stimulation by medium conditioned by activated mouse lymphoid cells. Megakaryocytes were identified on the basis of their morphology, polyploid mitoses and DNA content, and high cytoplasmic content of acetylcholinesterase. Megakaryocyte colony-forming cells were relatively small with a peak sedimentation velocity of 4.2 mm/hr. Spleen, lymph node, and thymus cells produced the factor stimulating megakaryocyte proliferation after culture in medium containing 2-mercaptoethanol, with or without added mitogens or allogeneic spleen cells. Peak activity in conditioning medium was associated with the small lymphocyte fractions in mouse spleen.

Animals↗