| 1. |
- Adolfsson, Jörgen, et al.
(författare)
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Identification of Flt3(+) lympho-myeloid stem cells lacking erythro-megakaryocytic potential: A revised road map for adult blood lineage commitment
- 2005
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Ingår i: Cell. - : Elsevier (Cell Press). - 0092-8674 .- 1097-4172. ; 121:2, s. 295-306
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Tidskriftsartikel (refereegranskat)abstract
- All blood cell lineages derive from a common hematopoietic stem cell (HSC). The current model implicates that the first lineage commitment step of adult pluripotent HSCs results in a strict separation into common lymphoid and common myeloid precursors. We present evidence for a population of cells which, although sustaining a high proliferative and combined lympho-myeloid differentiation potential, have lost the ability to adopt erythroid and megakaryocyte lineage fates. Cells in the Lin-Sca-1+c-kit+ HSC compartment coexpressing high levels of the tyrosine kinase receptor Flt3 sustain granulocyte, monocyte, and B and T cell potentials but in contrast to Lin-Sca-1(+)ckit(+)Flt3(-) HSCs fail to produce significant erythroid and megakaryocytic progeny. This distinct lineage restriction site is accompanied by downregulation of genes for regulators of erythroid and megakaryocyte development. In agreement with representing a lymphoid primed progenitor, Lin(-)Sca-l(+)c-kit(+)CD34(+)Flt3(+) cells display upregulated IL-7 receptor gene expression. Based on these observations, we propose a revised road map for adult blood lineage development.
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| 2. |
- Asp, Mihaela, et al.
(författare)
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Tru-Cut Biopsy in Gynecological Cancer: Adequacy, Accuracy, Safety and Clinical Applicability
- 2023
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Ingår i: Journal of Multidisciplinary Healthcare. - 1178-2390. ; 16, s. 1367-1377
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Tru-cut biopsy is a minimally invasive technique used to obtain tissue samples for the diagnosis of tumors, especially in patients where primary surgery is not indicated. The aim of this study was to assess the adequacy, accuracy and safety of the tru-cut biopsy for diagnosis in gynecological cancer.Methods: A retrospective population-based review of 328 biopsies was conducted. The indications for tru-cut biopsies were diagnosis of primary tumors, metastases of gynecological and non-gynecological tumors, and suspected recurrences. A tissue sample was considered adequate when the quality/quality was sufficient to identify the subtype/origin of the tumor. Potential factors affecting adequacy were analyzed using logistic regressions analyses. Accuracy was defined as agreement between the diagnosis of the tru-cut biopsy and the postoperative histology. The therapy plan was registered, and the clinical applicability of the tru-cut biopsy was investigated. Complications within 30 days after the biopsy procedure were registered.Results: In total, 300 biopsies were identified as tru-cut biopsies. The overall adequacy was 86.3%, varying between 80.8% and 93.5%, respectively, when performed by a gynecological oncologist or a gynecologist with a subspecialty in ultrasound diagnosis. Sampling of a pelvic mass had a lower adequacy (81.6%) compared with sampling of the omentum (93.9%) or carcinomatosis (91.5%). The accuracy was 97.5%, and the complication rate was 1.3%.Conclusion: The tru-cut biopsy is a safe and reliable diagnostic method with a high accuracy and a good adequacy, depending on the site of the tissue sample, indications for the biopsy and the experience of the operator.
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| 3. |
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| 4. |
- Hernandez-Andrade, Edgar, et al.
(författare)
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Perinatal adaptive response of the adrenal and carotid blood flow in sheep fetuses subjected to total cord occlusion
- 2005
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Ingår i: Journal of Maternal-Fetal & Neonatal Medicine. - 1476-7058. ; 17:2, s. 101-109
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To investigate the perinatal adaptive response of the adrenal blood flow/adrenal fractional moving blood volume (AFMBV) and carotid blood flow (CBF), in sheep fetuses subjected to severe acute intrauterine hypoxia/asphyxia induced by total cord occlusion.Methods. Adrenal blood flow velocity, AFMBV and CBF were measured in 13 exteriorized fetal sheep; eight of them underwent total umbilical cord occlusion to induce severe acute hypoxia/asphyxia. Five lambs were used as sham controls. Middle adrenal artery pulsatility index (MAAPI) and mean velocity (MAAMV) were recorded with pulsed Doppler ultrasound. AFMBV was estimated using power Doppler ultrasound. CBF was recorded with a transonic flowmeter. In the neonatal period, after resuscitation all lambs were followed for a 4-hour period and AFMBV and CBF were recorded. Mean arterial blood pressure (MABP) and fetal heart rate were recorded continuously. Arterial cortisol levels were measured at the beginning and at the end of the fetal and neonatal periods.Results. Following the total cord occlusion, there was a significant reduction in the CBF, MABP, and heart rate and adrenal flow/AFMBV after 2, 4 and 5?min, respectively. Cortisol levels in the asphyctic lambs at the end of the cord occlusion were significantly lower than those in controls. After resuscitation, the asphyctic lambs showed increased AFMBV and cortisol levels, and reduced MABP as compared to control lambs. No differences were found in CBF, MAAPI and MAAMV. Thereafter, no differences were observed between the two groups in any of the studied parameters. At the end of the cord occlusion period, there was a significant correlation between AFMBV and MABP (r?=?0.69), between AFMBV and CBF (r?=?0.65) and between CBF and MABP (r?=?0.89).Conclusion. During severe acute intrauterine hypoxia, the fetal lamb is able to maintain the blood flow to the brain and the adrenal gland for 3-5?min. Changes in the AFMBV and the CBF were highly correlated to the changes in MABP. Adrenal FMBV and cortisol levels were higher in lamb neonates exposed to severe intrauterine asphyxia.
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| 5. |
- Jensen, Christina, et al.
(författare)
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TSLP-mediated fetal B lymphopoiesis?
- 2007
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Ingår i: Nature Immunology. - : Springer Science and Business Media LLC. - 1529-2908 .- 1529-2916. ; 8:9, s. 897-897
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Tidskriftsartikel (refereegranskat)
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| 6. |
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| 7. |
- Liuba, Karina
(författare)
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Hematopoietic stem and progenitor cells and potentials for application in fetal cell replacement therapy
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Fetal cell replacement therapy or in utero hematopoietic cell transplantation (IUHCT) is proposed as a non-myeloablative alternative to bone marrow transplantation (BMT) for a number of inborn immunologic, hematologic and metabolic disorders. IUHCT represents the method through which variable amounts of natural or genetically modified hematopoietic cells can be transferred to the fetal recipient in hope of correcting the disorder and preventing postnatal permanent organ damage. Although proof-of-principle has been achieved by succesful correction of X linked severe combined immune deficiency (X-SCID), in the majority of target diseases treated with IUHCT engraftment was insufficient for clinical benefit. Thus, the therapeutical promise of IUHCT remains unfullfilled and many challenges stand. In the present thesis we investigate the optimal cell population for IUHCT by first identifying a novel commitment/differentiation step of hematopoietic stem cells (HSCs) in adult murine hematopoiesis and then evaluating the therapeutical potential of the lymphoid primed multipotent progenitors (LMPPs) for immune reconstitution in a model of fetal X-SCID transplantation. We find that LMPPs generate rapid and sustained lymphoid reconstitution with polyclonal T cells, but that HSCs are most likely required for long term engraftment. We also find that the fetal microenvironment is apparently more receptive to donor HSCs (but also LMPPs) as it allows higher levels of chimerism after IUHCT then after BMT in neonatal or adult age. In the last part we investigate in adult and fetal animal models the proposed plasticity of HSCs, a feature that holds promise for clinical BMT (or IUHCT) to non-hematopoietic disorders. We find that HSCs plasticity is a result of heterotypic cell fusion, probably induced by inflammation/injury in the target tissue. We also show that heterotypic cell fusion is not a physiological frequently occuring event during development and we demonstrate that not only myeloid, but also lymphoid cells are efficient fusogenic partners to non-hematopoietic tissues.
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| 8. |
- Liuba, Karina, et al.
(författare)
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Polyclonal T-cell reconstitution of X-SCID recipients after in utero transplantation of lymphoid-primed multipotent progenitors
- 2009
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 113:19, s. 4790-4798
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Tidskriftsartikel (refereegranskat)abstract
- Although successful in utero hematopoietic cell transplantation (IUHCT) of X-linked severe combined immune deficiency (X-SCID) with enriched stem and progenitor cells was achieved more than a decade ago, it remains applied only in rare cases. Although this in part reflects that postnatal transplantations have overall given good results, there are no direct comparisons between IUHCT and postnatal transplantations of X-SCID. The proposed tolerance of the fetal immune system to foreign human leukocyte antigen early in gestation, a main rationale behind IUHCT, has recently been challenged by evidence for a considerable immune barrier against in utero transplanted allogeneic bone marrow cells. Consequently, there is need for further exploring the application of purified stem and progenitor cells to overcome this barrier also in IUHCT. Herein, we demonstrate in a congenic setting that recently identified lymphoid-primed multipotent progenitors are superior to hematopoietic stem cells in providing rapid lymphoid reconstitution after IUHCT of X-SCID recipients, and sustain in the long-term B cells, polyclonal T cells, as well as short-lived B-cell progenitors and thymic T-cell precursors. We further provide evidence for IUHCT of hematopoietic stem cells giving superior B- and T-cell reconstitution in fetal X-SCID recipients compared with neonatal and adolescent recipients. (Blood. 2009;113:4790-4798)
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| 9. |
- Månsson, Robert, et al.
(författare)
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Molecular evidence for hierarchical transcriptional lineage priming in fetal and adult stem cells and multipotent progenitors
- 2007
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Ingår i: Immunity. - : Elsevier BV. - 1074-7613 .- 1097-4180. ; 26:4, s. 407-419
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies implicated the existence of adult lymphoid-primed multipotent progenitors (LMPPs) with little or no megakaryocyte-erythroid potential, questioning common myeloid and lymphoid progenitors as obligate intermediates in hematopoietic stem cell (HSC) lineage commitment. However, the existence of LMPPs remains contentious. Herein, global and single-cell analyses revealed a hierarchical organization of transcriptional lineage programs, with downregulation of megakaryocyte-erythroid genes from HSCs to LMPPs, sustained granulocyte-monocyte priming, and upregulation of common lymphoid (but not B and T cell-specific) genes. These biological and molecular relationships, implicating almost mutual exclusion of megakaryocyte-erythroid and lymphoid pathways, are established already in fetal hematopoiesis, as evidenced by existence of LMPPs in fetal liver. The identification of LMPPs and hierarchically ordered transcriptional activation and downregulation of distinct lineage programs is compatible with a model for HSC lineage commitment in which the probability for undergoing different lineage commitment fates changes gradually when progressing from HSCs to LMPPs.
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| 10. |
- Nygren, Jens Martin, 1976-, et al.
(författare)
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Myeloid and lymphoid contribution to non-haematopoietic lineages through irradiation-induced heterotypic cell fusion
- 2008
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Ingår i: Nature Cell Biology. - London : Nature Publishing Group. - 1465-7392 .- 1476-4679. ; 10:5, s. 584-92
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have suggested that regeneration of non-haematopoietic cell lineages can occur through heterotypic cell fusion with haematopoietic cells of the myeloid lineage. Here we show that lymphocytes also form heterotypic-fusion hybrids with cardiomyocytes, skeletal muscle, hepatocytes and Purkinje neurons. However, through lineage fate-mapping we demonstrate that such in vivo fusion of lymphoid and myeloid blood cells does not occur to an appreciable extent in steady-state adult tissues or during normal development. Rather, fusion of blood cells with different non-haematopoietic cell types is induced by organ-specific injuries or whole-body irradiation, which has been used in previous studies to condition recipients of bone marrow transplants. Our findings demonstrate that blood cells of the lymphoid and myeloid lineages contribute to various non-haematopoietic tissues by forming rare fusion hybrids, but almost exclusively in response to injuries or inflammation.
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