Animal Model Of Leukemia Research Articles

Comparative cytogenetic analysis between cyclophosphamide‐sensitive and ‐resistant lines of acute myeloid leukemia in the lewis brown norway hybrid rat

An animal model of acute myeloid leukemia (AML) has been developed in the Brown Norway (BN) rat and has successfully been introduced into the Lewis x BN F1 hybrid (LBN) and designated LBN AML. The original LBN AML is sensitive to the chemotherapeutic agent cyclophosphamide (CY). Recently, a CY-resistant cell line of LBN AML has been established. To characterize this animal model of human leukemia better, we analyzed and compared the chromosomal makeup of both the CY-sensitive and CY-resistant LBN AML lines. The CY-sensitive LBN AML cultures contained two cell lines--line I (88%): 41,XX,-1,-2,-9,del(12)(q16), + der(1)t(1;?8)(p13;q31), + der(2)t(2;9)(p11;q11); and line II (12%): 41,XX,-1,-2,-9,del(12),del(20)(q13) + der(1)t(1;?8)(p13;q31), + der(2)t(2;9)(p11;q11). The recently developed CY-resistant AML cells contained two cell lines--line I (88%): 41,XX,-1,-2,-9,del(3)(q36q42.1),del(4) (q42.2),?t(5;?)(q35;?),?t(8;?)(q24;?),del(12)(q16), + der(1)t(1;?8)(p13;q31), + der(2)t(2;9)(p11;q11); and line II (12%): 42,XX (probably represents host contamination). The new chromosomal aberrations in the CY-resistant line I [del(3)(q36q42.1),del(4)(q42.2),?t(5;?)(q35;?), and ?t(8;?)(q24;?)] suggest a possible interrelationship between these secondary karyotypic abnormalities and acquisition of resistance to the chemotherapeutic agent.

Experimental inoculation of monkeys with autologous lymphoid cell lines immortalized by and producing human T-cell leukemia virus type-I.

Cynomolgus monkeys and squirrel monkeys were inoculated with autologous lymphoid cell lines immortalized by and producing human T-cell leukemia virus type-I (HTLV-I) in order to serve as an animal model of adult T-cell leukemia (ATL). The autologous cell lines were established from peripheral blood mononuclear cells (PBMC) from each monkey by co-cultivation with lethally irradiated MT-2 cells producing HTLV-I. All of these cell lines, which had monkey karyotypes, grew continuously without addition of interleukin-2 (IL-2) and expressed virus-specific proteins of HTLV-I and IL-2 receptor. After inoculation with the autologous cell lines, specific antibodies against HTLV-I proteins could be detected in their plasma, and transformed HTLV-I-infected cells could be recovered from their peripheral blood for at least 6 months. However, no signs of ATL have been observed to data, i.e. 2 years after inoculation.

Metabolic stability of experimental chemotherapeutic agents in hepatocyte:tumor cell co-cultures.

A U.S. National Cancer Institute screening program for new anticancer drugs, based on the growth of primary human tumor cells in an in vitro soft agar colony formation assay, has resulted in the identification of a number of compounds that have cytotoxic activity against primary human tumor cells in vitro but are inactive in the conventional in vivo murine P388 leukemia animal model pre-screen. To investigate whether metabolic inactivation ov the compounds might be a factor in the lack of in vivo cytotoxicity we have co-cultured rat hepatocytes with A204 rhabdomyosarcoma and murine P388 leukemia cell lines in the soft agarose colony formation assay for 24 h during exposure to the compounds. Twenty compounds with a range of in vitro activities were studied. Thirteen compounds exhibited cytotoxicity against A204 cells in culture; nine of them were less active when co-cultured with hepatocytes, two were activated by hepatocyte co-culture, and two showed no effect of hepatocyte co-culture. P388 cells were more sensitive to the antiproliferative effects of the compounds than A204 cells. Two compounds that were not active against A204 cells exhibited cytotoxicity against P388 cells. One compound was inactivated by hepatocyte co-culture and one showed no effect. Five compounds showed no cytotoxicity toward either A204 cells or P388 cells. Two of the compounds showing hepatocyte inactivation in vitro possess activity in one or more in vivo tumor models. Thus, evidence for metabolic inactivation in hepatocyte co-culture is not always an indication for lack of in vivo antitumor activity. Hepatocyte co-culture methodology provides a simple and objective means, amenable to large-scale screening, of distinguishing metabolic activation or inactivation of a given compound from other pharmacokinetic and pharmacodynamic factors with a minimum of material.