Cytogenetic Studies on Goat Blood Lymphocytes:Cell Cycling

Peripheral blood lymphocytes from goats (local breed) were cultivated in RPMI-1640 medium containing 15µg/ml of BudR 20 µg/ml of PHA for different times (12, 24, 36, 48, 60, 72 and 96( hrs. to determination the cell cycle duration. Blastogenesis was appeared post first 12hr of cultivation followed by first mitoses post 24 hrs. of culture initiation. The second and third cell cycling lasted 22 and 21 hrs, respectively. Effects of 6-thioguanine, methotrexate , colchicine and tamoxifen on cell cycle progression were investigated. Goat cells were found to be resistant to tamoxifen and MTX and sensitive to 6 TG and colchicine, which could be use as genetic markers to chick cellular genome integrity. Priming of goat blood lymphocytes was achieved by treating the blood with PHA for 24hr. Such treatment increased the in vitro growing period of derived lymphoblasts with short cycling time. However, PHA was found to be a promoting factor for initiation of blastogenesis and cell divisions in goat blood lymphoblasts. These techniques: Genetic markers, cytogenetic analysis cell cycling and lymphoblast explantation are crucial processes for nuclear transplantation processes.

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Cytogenetic Analysis of Goat Blood Lymphocytes cultured in Vitro

Journal of Biotechnology Research Center ◽

10.24126/jobrc.2010.4.1.101 ◽

2010 ◽

Vol 4 (1) ◽

pp. 85-91

Author(s):

Shubber E. K ◽

Z. M. T. JAAFER ◽

A. A. Tawfeek ◽

M. I. Sebbah

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Peripheral Blood Lymphocytes ◽

Sister Chromatid Exchanges ◽

Lymphocyte Culture ◽

Cycle Duration ◽

Cycle Progression ◽

Blood Lymphocytes ◽

Lymphocyte Blastogenesis

The aim of this work is to determine the duration of goat cell cycling in vitro.Goat peripheral blood lymphocytes were grown in RPMI-1640 medium containing bromodeoxyuridine (BrdU 10 μg/ml) for 72 h. Blastogenic index (BI), mitotic index (MI), cell cycle progression (CCP) and sister chromatid exchanges (SCE) were determined. Cultured lymphocytes from, whole blood or from leukocyte rich plasma in RPMI-1640 medium containing BrdU showed little differences in BI, MI, but significant differences were seen in cell cycle progression. BI, MI, and CCP from different goat breed were compared. Also, the percentage of lymphocyte blastogenesis, mitoses and cell cycle progression from goat, were compared to those from sheep, and human whichgrown under similar conditions. On successive incubation periods, the cell cycle duration of blood lymphocytes was determined through the mitotic activity. The cells reached first, second and third mitoses after 25, 40 and 48 h, post incubation respectively. Sub culturing of growing lymphocytes was performed from 3 to 45 days to obtain a lymphoblastoid cells. The characterization of their differentiation is required Establishment of goat blood lymphocyte culture will help in gene marker’s detection in their somatic cells.

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Applications of Human Peripheral Blood Lymphocytes in Genotoxicity and Cytotoxicity

Alternatives to Laboratory Animals ◽

10.1177/026119299001800123.1 ◽

1990 ◽

Vol 18 (1_part_1) ◽

pp. 231-241

Author(s):

Lucia Celotti ◽

Vera Bianchi

Keyword(s):

Cell Cycle ◽

Peripheral Blood ◽

Mammalian Cells ◽

Cell Cycle Progression ◽

Human Peripheral Blood ◽

Quantitative Difference ◽

Peripheral Blood Lymphocytes ◽

Blood Lymphocytes

A number of features make peripheral blood lymphocytes an excellent system for studying both genotoxicity and cytotoxicity in humans. They are an abundant and readily accessible source of somatic cells, mostly in a non-proliferative state, but able to be stimulated by mitogens to enter the cell cycle. The blastocyte transformation of lymphocytes is a useful model for investigating the mechanisms which regulate cell-cycle progression in mammalian cells. By stimulating lymphocytes in vitro, it is possible to detect the genetic damages they have sustained in vivo, which become manifest as chromosomal aberrations, sister-chromatid exchanges or gene mutations. The metabolic properties of lymphocytes have been extensively studied, especially with reference to their characteristic collection of enzymes involved in nucleotide turnover, which makes them exquisitely sensitive to changes in intracellular levels of DNA precursors. The data collected on the ability of lymphocytes to metabolise xenobiotics show a marked quantitative difference between resting and proliferating lymphocytes, and minor qualitative differences between lymphocytes and other cell types, e.g. hepatocytes. An indirect approach to detect the metabolism of genotoxic xenobiotics by lymphocytes is the analysis of DNA adducts in their chromatin after in vivo or in vitro exposure. Lymphocytes can be employed to identify the (cyto)genetic consequences of in vivo genotoxic exposure and inter-individual variation in sensitivity to genotoxic agents. The analysis of mutations at the hgprt locus in lymphocytes is a promising approach for the study of somatic-cell mutations in humans and of the possible mechanisms of in vivo selection against mutants. In the field of cytotoxicity, the applications of lymphocytes are, as yet, still few: the main effect measured is the impairment of the proliferative response to mitogens. But lymphocytes can be employed as primary human cells to be treated in vitro with mutagenic or toxic chemicals in standard genotoxicity and cytotoxicity assays, and offer the advantage of avoiding the problems of inter-species extrapolation of results by testing in a human system. Moreover, the (geno)toxic effects detected in lymphocytes after treatments in vitro may give information on the spontaneous or environmentally-determined susceptibility of the individual donors to xenobiotics.

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The Novel Vascular Disrupting Agent ANG501 Induces Cell Cycle Arrest and Enhances Endothelial Cell Sensitivity to Radiation

Cancer Growth and Metastasis ◽

10.4137/cgm.s2596 ◽

2009 ◽

Vol 2 ◽

pp. CGM.S2596 ◽

Cited By ~ 2

Author(s):

Shona T. Dougherty ◽

Sean E. Walker ◽

Peter D. Davis ◽

Graeme J. Dougherty

Keyword(s):

Cell Cycle ◽

Endothelial Cells ◽

Normal Cell ◽

Cell Cycle Progression ◽

Stress Proteins ◽

Vascular Disrupting Agent ◽

Heat Shock Stress ◽

Cell Cycling ◽

Vascular Disrupting

The efficacy of approaches in which vascular disrupting agents (VDA) are used in combination with conventional chemotherapy and/or radiation therapy in the treatment of cancer might be improved if there were a better understanding of the cellular and molecular changes induced in normal and malignant cells as a result of VD A exposure. Toward this goal, murine endothelial cells were treated in vitro with ANG501, a novel stilbene VDA developed in our laboratory, and alterations in gene expression determined by genome-wide microarray analysis and subsequently confirmed by Western blot analysis. Among the genes that were shown to be induced upon brief exposure to non-cytotoxic doses of ANG501 were several involved in the control of cell cycle progression and apoptosis, including p21Wafl and the heat shock/stress proteins hsp25, hsp70 and anti-B-crystallin. Reflecting such induction, functional studies confirmed that normal cell cycling is temporarily inhibited following treatment with ANG501 such that the majority of cells accumulate at the radiation-sensitive G2/M phase of the cell cycle at 6 hr. The effects were transient and by 24 hr normal cell cycling had largely resumed. Combination experiments confirmed that endothelial cells treated 6 hr previously with ANG501 were more readily killed by radiation. Importantly, significant effects were evident at clinically relevant radiation doses. Taken together these findings emphasize the need to consider the radiosensitizing activity of VD As when developing therapies in which these promising compounds are used in combination with radiation.

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