Name: bone marrow transplantation procedures in mice to study clonal hematopoiesis
Uploaded: 2021-05-26T13:00:00
Description: Watch this Scientific Journal Video about Bone Marrow Transplantation Procedures in Mice to Study Clonal Hematopoiesis at JoVE.com

This work was supported by US National Institutes of Health grants to K. Walsh (HL131006, HL138014, and HL132564), to S. Sano (HL152174), American Heart Association grant to M. A. Evans (20POST35210098), and a Japan Heart Foundation grant to H. Ogawa.

All procedures involving animal subjects have been approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Virginia.
1. Prior to preconditioning
<ol>
	<li>Place the recipient mice on antibiotic-supplemented water (5 mM sulfamethoxazole, 0.86 mM trimethoprim) ~24 h prior to irradiation. This is necessary to prevent infection, as the immune system will be suppressed following irradiation, and maintained for 2 weeks following irradiation. At this point, suppleme...

<ol>
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S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+origin+and+evolution+of+mutations+in+acute+myeloid+leukemia.">The origin and evolution of mutations in acute myeloid leukemia.</a> Cell. 150 (2), 264-278 (2012).</li><li>Jaiswal, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-related+clonal+hematopoiesis+associated+with+adverse+outcomes.">Age-related clonal hematopoiesis associated with adverse outcomes.</a> New England Journal of Medicine. 371 (26), 2488-2498 (2014).</li><li>Dorsheimer, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Association+of+mutations+contributing+to+conal+hematopoiesis+with+prognosis+in+chronic+ischemic+heart+failure.">Association of mutations contributing to conal hematopoiesis with prognosis in chronic ischemic heart failure.</a> JAMA Cardiology. 4 (1), 25 (2019).</li><li>Genovese, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+hematopoiesis+and+blood-cancer+risk+inferred+from+blood+DNA+sequence.">Clonal hematopoiesis and blood-cancer risk inferred from blood DNA sequence.</a> New England Journal of Medicine. 371 (26), 2477-2487 (2014).</li><li>Jaiswal, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+hematopoiesis+and+risk+of+atherosclerotic+cardiovascular+disease.">Clonal hematopoiesis and risk of atherosclerotic cardiovascular disease.</a> New England Journal of Medicine. 377 (2), 111-121 (2017).</li><li>Bick, A. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+interleukin+6+signaling+deficiency+attenuates+cardiovascular+risk+in+clonal+hematopoiesis.">Genetic interleukin 6 signaling deficiency attenuates cardiovascular risk in clonal hematopoiesis.</a> Circulation. 141 (2), 124-131 (2020).</li><li>Fuster, J. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+hematopoiesis+associated+with+TET2+deficiency+accelerates+atherosclerosis+development+in+mice.">Clonal hematopoiesis associated with TET2 deficiency accelerates atherosclerosis development in mice.</a> Science. 355 (6327), 842-847 (2017).</li><li>Wang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tet2-mediated+clonal+hematopoiesis+in+nonconditioned+mice+accelerates+age-associated+cardiac+dysfunction.">Tet2-mediated clonal hematopoiesis in nonconditioned mice accelerates age-associated cardiac dysfunction.</a> JCI Insight. 5 (6), 135204 (2020).</li><li>Sano, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tet2-mediated+clonal+hematopoiesis+accelerates+heart+failure+through+a+mechanism+involving+the+IL-1&#946;/NLRP3+inflammasome.">Tet2-mediated clonal hematopoiesis accelerates heart failure through a mechanism involving the IL-1&#946;/NLRP3 inflammasome.</a> Journal of the American College of Cardiology. 71 (8), 875-886 (2018).</li><li>Sano, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=JAK2-mediated+clonal+hematopoiesis+accelerates+pathological+remodeling+in+murine+heart+failure.">JAK2-mediated clonal hematopoiesis accelerates pathological remodeling in murine heart failure.</a> JACC: Basic to Translational Science. 4 (6), 684-697 (2019).</li><li>Yu, K. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+aging+on+primate+hematopoiesis+as+interrogated+by+clonal+tracking.">The impact of aging on primate hematopoiesis as interrogated by clonal tracking.</a> Blood. 131 (11), 1195-1205 (2018).</li><li>Sano, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CRISPR-mediated+gene+editing+to+assess+the+roles+of+Tet2+and+Dnmt3a+in+clonal+hematopoiesis+and+cardiovascular+disease.">CRISPR-mediated gene editing to assess the roles of Tet2 and Dnmt3a in clonal hematopoiesis and cardiovascular disease.</a> Circulation Research. 123 (3), 335-341 (2018).</li><li>Stachura, D. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+analysis+of+hematopoietic+progenitor+cells+in+the+zebrafish.">Clonal analysis of hematopoietic progenitor cells in the zebrafish.</a> Blood. 118 (5), 1274-1282 (2011).</li><li>Gyurkocza, B., Sandmaier, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conditioning+regimens+for+hematopoietic+cell+transplantation:+one+size+does+not+fit+all.">Conditioning regimens for hematopoietic cell transplantation: one size does not fit all.</a> Blood. 124 (3), 344-353 (2014).</li><li>Bacigalupo, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defining+the+intensity+of+conditioning+regimens:+working+definitions.">Defining the intensity of conditioning regimens: working definitions.</a> Biology of Blood and Marrow Transplantation. 15 (12), 1628-1633 (2009).</li><li>Abbuehl, J. P., Tatarova, Z., Held, W., Huelsken, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+engraftment+of+primary+bone+marrow+stromal+cells+repairs+niche+damage+and+improves+hematopoietic+stem+cell+transplantation.">Long-term engraftment of primary bone marrow stromal cells repairs niche damage and improves hematopoietic stem cell transplantation.</a> Cell Stem Cell. 21 (2), 241-255 (2017).</li><li>Shao, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+body+irradiation+causes+long-term+mouse+BM+injury+via+induction+of+HSC+premature+senescence+in+an+Ink4a-+and+Arf-independent+manner.">Total body irradiation causes long-term mouse BM injury via induction of HSC premature senescence in an Ink4a- and Arf-independent manner.</a> Blood. 123 (20), 3105-3115 (2014).</li><li>Cui, Y. Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+protocol+for+total+body+irradiation+for+allogeneic+bone+marrow+transplantation+in+mice.">Optimal protocol for total body irradiation for allogeneic bone marrow transplantation in mice.</a> Bone Marrow Transplantation. 30 (12), 843-849 (2002).</li><li>Koch, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+of+early+endpoints+in+mouse+total-body+irradiation+model.">Establishment of early endpoints in mouse total-body irradiation model.</a> PLOS One. 11 (8), 0161079 (2016).</li><li>Ismaiel, A., Dumitra&#351;cu, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+risk+in+fatty+liver+disease:+the+liver-heart+axis-literature+review.">Cardiovascular risk in fatty liver disease: the liver-heart axis-literature review.</a> Frontiers in Medicine. 6, 202 (2019).</li><li>Amann, K., Wanner, C., Ritz, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cross-talk+between+the+kidney+and+the+cardiovascular+system.">Cross-talk between the kidney and the cardiovascular system.</a> Journal of the American Society of Nephrology. 17 (8), 2112-2119 (2006).</li><li>Liao, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+roles+of+resident+and+nonresident+macrophages+in+nonischemic+cardiomyopathy.">Distinct roles of resident and nonresident macrophages in nonischemic cardiomyopathy.</a> Proceedings of the National Academy of Sciences. 115 (20), 4661-4669 (2018).</li><li>Honold, L., Nahrendorf, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resident+and+monocyte-derived+macrophages+in+cardiovascular+disease.">Resident and monocyte-derived macrophages in cardiovascular disease.</a> Circulation Research. 122 (1), 113-127 (2018).</li><li>Lavine, K. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+macrophage+in+cardiac+homeostasis+and+disease.">The macrophage in cardiac homeostasis and disease.</a> Journal of the American College of Cardiology. 72 (18), 2213-2230 (2018).</li><li>Ginhoux, F., Guilliams, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue-resident+macrophage+ontogeny+and+homeostasis.">Tissue-resident macrophage ontogeny and homeostasis.</a> Immunity. 44 (3), 439-449 (2016).</li><li>Mildner, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microglia+in+the+adult+brain+arise+from+Ly-6C+hi+CCR2++monocytes+only+under+defined+host+conditions.">Microglia in the adult brain arise from Ly-6C hi CCR2+ monocytes only under defined host conditions.</a> Nature Neuroscience. 10 (12), 1544-1553 (2007).</li><li>Cronk, J. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peripherally+derived+macrophages+can+engraft+the+brain+independent+of+irradiation+and+maintain+an+identity+distinct+from+microglia.">Peripherally derived macrophages can engraft the brain independent of irradiation and maintain an identity distinct from microglia.</a> Journal of Experimental Medicine. 215 (6), 1627-1647 (2018).</li><li>Lu, R., Czechowicz, A., Seita, J., Jiang, D., Weissman, I. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal-level+lineage+commitment+pathways+of+hematopoietic+stem+cells+in+vivo.">Clonal-level lineage commitment pathways of hematopoietic stem cells in vivo.</a> Proceedings of the National Academy of Sciences. 116 (4), 1447-1456 (2019).</li><li>Gibson, B. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+cesium-137+and+X-ray+irradiators+by+using+bone+marrow+transplant+reconstitution+in+C57BL/6J+mice.">Comparison of cesium-137 and X-ray irradiators by using bone marrow transplant reconstitution in C57BL/6J mice.</a> Comparative Medicine. 65 (3), 165-172 (2015).</li><li>Cui, Y. Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+protocol+for+total+body+irradiation+for+allogeneic+bone+marrow+transplantation+in+mice.">Optimal protocol for total body irradiation for allogeneic bone marrow transplantation in mice.</a> Bone Marrow Transplantation. 30 (12), 843-849 (2002).</li><li>Kim, C. K., Yang, V. W., Bialkowska, A. 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For studies of clonal hematopoiesis, we described three methods of BMT: BMT with total-body irradiation, BMT with irradiation with partial shielding, and a less commonly used BMT method that involves no pre-conditioning (adoptive BMT). These methods have been used to assess the impact of clonal hematopoiesis on cardiovascular disease. Researchers can modify these methods accordingly to suit the specific purpose of their study.
Clonal hematopoiesis models 
Clonal hematopoi...

Clonal hematopoiesis (CH) is a condition which is frequently observed in elderly individuals and occurs as a result of an expanded hematopoietic stem and progenitor cell (HSPC) clone carrying a genetic mutation1. It has been suggested that by the age of 50, most individuals will have acquired an average of five exonic mutations in each HSPC2, but most of these mutations will result in little or no phenotypic consequences to the individual. However, if by chance one of these mutations confers a competitive advantage to the HSPC&#8212;such as by promoting it&#8217;s proliferation, self-renewal, survival, or some combination of these&#8212;this may lead to the preferential expansion of the mutant clone relative to the other HSPCs. As a result, the mutation will increasingly spread through the hematopoietic system as the mutated HSPC gives rise to mature blood cells, leading to a distinct population of mutated cells within the peripheral blood. While mutations in dozens of different candidate driver genes have been associated with clonal events within the hematopoietic system, among these, mutations in DNA methyltransferase 3 alpha (DNMT3A) and ten eleven translocation 2 (TET2) are the most prevalent3. Several epidemiological studies have found that individuals who carry these genetic mutations have a significantly higher risk of cardiovascular disease (CVD), stroke, and all-causal mortality3,4,5,6,7. While these studies have identified that an association exists between CH and increased incidence of CVD and stroke, we do not know whether this relationship is causal or a shared epiphenomenon with the aging process. To gain a better understanding of this association, proper animal models that correctly recapitulate the human condition of CH are required.
Several CH animal models have been established by our group and others using zebrafish, mice, and non-human primates8,9,10,11,12,13,14. These models often use hematopoietic reconstitution methods by transplantation of genetically modified cells, sometimes using Cre-lox recombination or the CRISPR system. This approach allows for the analysis of a specific gene mutation in hematopoietic cells to assess how it contributes to disease development. In addition, these models often employ congenic or reporter cells to distinguish the effects of mutant cells from normal or wild-type cells. In many cases, a pre-conditioning regimen is required to successfully engraft donor hematopoietic stem cells.
Currently, the transplantation of bone marrow to recipient mice can be divided into two main categories: 1) myeloablative conditioning and 2) non-conditioned transplantation. Myeloablative conditioning can be achieved by one of two methods, namely, total body irradiation (TBI) or chemotherapy15. TBI is carried out by subjecting the recipient to a lethal dose of gamma or X-ray irradiation, generating DNA breaks or cross-links within rapidly dividing cells, rendering them irreparable16. Busulfan and cyclophosphamide are two commonly used chemotherapy drugs that disrupt the hematopoietic niche and similarly cause DNA damage to rapidly dividing cells. The net result of myeloablative preconditioning is apoptosis of hematopoietic cells, which destroys the recipient&#8217;s hematopoietic system. This strategy not only allows for the successful engraftment of the donor HSPCs, but can also prevent graft rejection by suppressing the recipient&#8217;s immune system. However, myeloablative preconditioning has severe side effects such as damage to tissues and organs and their resident immune cells as well as destruction of the native bone marrow niche17. Therefore, alternative methods have been proposed to overcome these undesirable side effects, particularly in regard to damage to the organs of interest. These methods include shielded irradiation of recipient mice and the adoptive BMT to non-conditioned mice9,17. Shielding the thorax, abdominal cavity, head or other regions from irradiation by the placement of a lead barriers keeps tissues of interest protected from the damaging effects of irradiation and maintains their resident immune cell population. On the other hand, the adoptive BMT of HSPCs to non-conditioned mice has an additional advantage because it preserves the native hematopoietic niche. In this manuscript, we describe the protocols and results of HSPC engraftment after several transplantation regimens in mice, specifically the delivery of HSPC to TBI mice, to mice partially shielded from irradiation, and to non-conditioned mice. The overall goal is to help researchers understand the different physiological effects of each method as well as how they affect experimental outcomes in the setting of CH and cardiovascular disease.

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bone marrow transplantation procedures in mice to study clonal hematopoiesis

Clonal hematopoiesis is a prevalent age-associated condition that results from the accumulation of somatic mutations in hematopoietic stem and progenitor cells (HSPCs). Mutations in driver genes, that confer cellular fitness, can lead to the development of expanding HSPC clones that increasingly give rise to progeny leukocytes harboring the somatic mutation. Because clonal hematopoiesis has been associated with heart disease, stroke, and mortality, the development of experimental systems that model these processes is key to understanding the mechanisms that underly this new risk factor. Bone marrow transplantation procedures involving myeloablative conditioning in mice, such as total-body irradiation (TBI), are commonly employed to study the role of immune cells in cardiovascular diseases. However, simultaneous damage to the bone marrow niche and other sites of interest, such as the heart and brain, is unavoidable with these procedures. Thus, our lab has developed two alternative methods to minimize or avoid possible side effects caused by TBI: 1) bone marrow transplantation with irradiation shielding and 2) adoptive BMT to non-conditioned mice. In shielded organs, the local environment is preserved allowing for the analysis of clonal hematopoiesis while the function of resident immune cells is unperturbed. In contrast, the adoptive BMT to non-conditioned mice has the additional advantage that both the local environments of the organs and the hematopoietic niche are preserved. Here, we compare three different hematopoietic cell reconstitution approaches and discuss their strengths and limitations for studies of clonal hematopoiesis in cardiovascular disease.

To compare the effect of three BMT/pre-conditioning methods on donor cell engraftment, the fractions of donor cells in peripheral blood and heart tissue were analyzed by flow cytometry at 1-month post-BMT. Isolated cells were stained for specific leukocyte markers to identify the different subsets of leukocytes. In these experiments, wild-type (WT) C57BL/6 (CD45.2) donor bone marrow cells were delivered to WT B6.SJL-PtprcaPrpcb/BoyJ (CD45.1) reci...

Watch this Scientific Journal Video about Bone Marrow Transplantation Procedures in Mice to Study Clonal Hematopoiesis at JoVE.com

Bone Marrow Transplantation Procedures in Mice to Study Clonal Hematopoiesis

We describe three methods of bone marrow transplantation (BMT): BMT with total-body irradiation, BMT with shielded irradiation, and BMT method with no pre-conditioning (adoptive BMT) for the study of clonal hematopoiesis in mouse models.

Clonal hematopoiesis is a prevalent age-associated condition that results from the accumulation of somatic mutations in hematopoietic stem and progenitor ...

Our protocol will help researchers understand the physiological effects of three different bone marrow transplantation methods and how they affect experimental outcomes in clonal hematopoiesis setting. Total body radiation bone marrow transplantation can negatively impact cardiovascular organs and alter disease pathogenesis. Thus, our lab has developed two alternative methods to minimize or avoid possible side-effects.Demonstrating the procedures will be Eunbee Park a graduate student, and Megan Evans a postdoctoral fellow, both from my laboratory For thorax and abdomen shielding, place the adjustable tray and the x-ray irradiator at the correct distance to achieve uniform irradiation. And place the anesthetized mice on a flat led plate inverted to each other in the supine position. Secure the paws to the plate with tape, and place the led shielding so that the lower end aligns with the xiphisternum bone and the upper end of the lead shield sits near the thymus.After shielding, place the mice into the irradiator and expose the animals to two, 5.5 gray fractions of irradiation separated by a four to 24 hour interval. For head shielding, carefully tape the four paws of the mouse to the abdomen. Place the mouse in a conical restrainer and slide the restrainer into the slot within the lead shield so that the mouse's head and ears are completely covered, leaving the rest of the mouse's body exposed for a radiation.After shielding place the mice into the irradiator and expose the animals to, to 5.5 gray fractions of a radiation separated by a four to 24 hour interval. After each radiation treatment, place the anesthetized mice in a cage on a heated mat with monitoring until fully recovered. To isolate the bones, disinfect the skin of the donor mouse with 70%ethanol and make a small transverse skin incision below the rib cage.Holding the skin tightly at either side of the incision, tear in opposite directions towards the head and feet and peel the skin from all of the limbs. Cut over the shoulders and elbow joints, and use a lab wipe to remove the attached muscles and connective tissues from the humeri. Carefully dislocate the joints between the femur and hip bones.And use blunt scissors to cut along the femoral heads to detach the legs. Cut over the knee joint, to separate the femur and tibia. And use lab wipes to carefully remove the attached muscles and connective tissues from the bones.Then pull the bones from mice of the same genotype into individual 50 milliliter conical tubes containing 20 milliliters of ice cold sterile PBS on ice. To isolate the bone marrow cells in a bio-safety class two cabinet, use an 18 gauge needle to make a small hole in the bottom of a sterile 500 microliter micro tube. And place the tube into an individual sterile 1.5 milliliter micro centrifuge tube containing 100 microliters of ice cold sterile PBS.When all of the tubes have been prepared, remove the PBS from the tube containing the isolated bones and transfer the bones onto a sterile 100 millimeter cell culture dish. Use fine forceps and small scissors to carefully remove the epiphysis from the ends of each bone, and place up to six bones into each 500 microliter tube. When all of the bones have been cut, extract the bone marrow cells by centrifugation.If all the marrow contents have been removed, the bones should appear white and translucent with a relatively large red pellet at the bottom of the 1.5 milliliter micro centrifuge tube. For bone marrow cell transplant, dilute the isolated bone marrow cells in serum free RPMI media, and load 200 microliters of the cell suspension into one 0.5 milliliter insulin syringe per mouse to be injected. After confirming a lack of response to pedal reflex, slowly inject the entire volume of cells into the retro orbital vein of each anesthetized recipient animal.Then place a drop of proparacaine onto the eye for pain relief. And allow the mouse to regain consciousness while being monitored. To compare the effect of three BMT preconditioning methods on donor cell engraftment.The fractions of donor cells in peripheral blood and heart tissue were analyzed by flow cytometry at one month post BMT. In this representative analysis, in the peripheral blood of recipient mice that received total body irradiation, monocytes, neutrophils and B cells were largely ablated and replaced by the progeny of donor bone marrow derived cells. In addition, the resident recipient cardiac monocyte and neutrophil populations were almost completely replaced by donor derived cells.In the partially shielded irradiation group, the donor derived cardiac immune cell replacement was modest. The recipient mouse bone marrow cells within the shielded regions likely contributed to the lower level of peripheral blood reconstitution compared to mice that received total body irradiation. In the group without BMT preconditioning, donor derived cells were detectable in the peripheral blood and hearts of recipient mice at four weeks post BMT.In addition, Tet2 deficient donor cells gradually expanded over time. In comparison, recipient mice engrafted with wild type donor cells showed minimal clonal expansion of donor cells. They optimization of these experimental models will enable more rigorous studies of the clonal hematopoiesis driver genes that contribute to all cause mortality such as cardio-metabolic disease and cancer.We hope that our protocols will allow researchers to study clonal hematopoiesis to investigate how it contributes to cardiovascular disease and other disease states.

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SCIENTISTS IN ACTION

Differentiating Functional Roles of Gene Expression from Immune and Non-immune Cells in Mouse Colitis by Bone Marrow Transplantation

To understand the role of a gene in the development of colitis, we compared the responses of wild-type mice and gene-of-interest deficient knockout mice ...

Investigation of Macrophage Polarization Using Bone Marrow Derived Macrophages

The article describes a readily easy adaptive in vitro model to investigate macrophage polarization. In the presence of GM-CSF/M-CSF, hematopoietic ...

Bone Marrow-derived Macrophage Production

Macrophages are critical components of the innate and adaptive immune responses, and they are the first line of defense against foreign invaders because ...

Transplantation of Tail Skin to Study Allogeneic CD4 T Cell Responses in Mice

The study of T cell responses and their consequences during allo-antigen recognition requires a model that enables one to distinguish between donor and ...

Isolation and Intravenous Injection of Murine Bone Marrow Derived Monocytes

As a subtype of leukocytes and progenitors of macrophages, monocytes are involved in many important processes of organisms and are often the subject of ...

Tracking Mouse Bone Marrow Monocytes In Vivo

Tracking Mouse Bone Marrow Monocytes In Vivo

Real time multiphoton imaging provides a great opportunity to study cell trafficking and cell-to-cell interactions in their physiological 3-dimensionnal ...

Murine Hind Limb Long Bone Dissection and Bone Marrow Isolation

Investigation of the bone and the bone marrow is critical in many research fields including basic bone biology, immunology, hematology, cancer metastasis, ...

Retroviral Transduction of Bone Marrow Progenitor Cells to Generate T-cell Receptor Retrogenic Mice

T cell receptor (TCR) signaling is essential in the development and differentiation of T cells in the thymus and periphery, respectively.  The vast array ...

Isolation of Lamina Propria Mononuclear Cells from Murine Colon Using Collagenase E

The intestine is the home to the largest number of immune cells in the body. The small and large intestinal immune systems police exposure to exogenous ...

Bone Marrow Transplantation Platform to Investigate the Role of Dendritic Cells in Graft-versus-Host Disease

Allogeneic bone marrow transplantation (BMT) is an effective therapy for hematological malignancies due to the graft-versus-leukemia (GVL) effect to ...