Role of inflammation in NRAS-G12D+ acute myeloid leukemia (transfer to Tromsø)
The aim of this project is to study the contribution of the anti-inflammatory properties of the hematopoietic system to acute myeloid leukemia (AML). We will use C57BL/6J WT mice as recipient of bone marrow cells from polyinosinic polycytidylic acid (pI:pC) induced IL-1rn KO x Mx1-Cre NRASG12D/+ and control mice. Prior to transplantation, recipient mice need to be myeloablated through whole body irradiation. Total whole body irradiation is used in the field of blood stem cell function and cancer. It allows to kill proliferating blood cells without significant damage of resting tissues, and simultaneously promotes proliferation of transplanted cells. The irradiation (12Gy) will be performed in two half doses, 3-4 hours apart,to reduce the adverse effects Mice might not feel well for the first 7-14 days and may lose up to 26% of their body weight, which after transplant, will be mostly regained by Day 14-21 post-irradiation. Animals should be on their way to recovery at day 21 (cut-off weight loss 15%), and recovered at day 30 (cut-off weight loss 10%). All mice will be transplanted after irradiation. We aim to further investigate the contribution of IL-1rn deletion together with NRASG12D/+ mutation using a transgenic mouse model, IL-1rn KO x Mx1-Cre NRASG12D/+. This will give a more comprehensive picture of the role of Il-1rn deficiency in AML. Using the therapeutic approach bortezomib, we aim to rescue Nras G12D/+ mice phenotype, providing new insights into the treatment of leukemia. Total Numbers of mice will be 521 in AKM Tromsø, and 459 in KPM Oslo; including additional experiments deleting IL-1B.
It is not the goal of this study to analyse terminal stages. Mice will be used in the most efficient way and numbers kept to minimum.
It is not the goal of this study to analyse terminal stages. Mice will be used in the most efficient way and numbers kept to minimum.
Etterevaluering
The Norwegian Food Safety Authority must retrospectively assess all severe experiments.
Begrunnelse for etterevalueringen
We have published that imbalance towards pro-inflammatory IL-1ß at the expense of anti-inflammatory IL-1 receptor antagonist is associated with apoptosis of the bone marrow niche cells and progression of myeloid malignancy in Nras-G12D pre-leukemic mice. Targeting of this imbalance towards physiological level is beneficial, and is a promising therapeutic strategy to investigate in human.
We have now complemented these studies under this FOTS, which has allowed us to harvest material to provide further insights into the cellular origin of inflammation in a pre-leukemic mouse model driven by Nras-G12D .
Animals with actual severity were animals terminated because of humane endpoint or found dead for unknown reasons. Severity as expected.
We always use in vitro and ex vivo experiments when appropriate, before performing in vivo experiments; transplantation is only performed by experienced researchers; and animals are followed up closely with use of score sheets. As a recent improvement, the conditions are kept sterile starting one week before performing the transplant in this and all our current FOTS.
We have now complemented these studies under this FOTS, which has allowed us to harvest material to provide further insights into the cellular origin of inflammation in a pre-leukemic mouse model driven by Nras-G12D .
Animals with actual severity were animals terminated because of humane endpoint or found dead for unknown reasons. Severity as expected.
We always use in vitro and ex vivo experiments when appropriate, before performing in vivo experiments; transplantation is only performed by experienced researchers; and animals are followed up closely with use of score sheets. As a recent improvement, the conditions are kept sterile starting one week before performing the transplant in this and all our current FOTS.