To gain insight into the clonal organization of lymphoid organs, we studied the distribution in situ of donor-derived cells in near-physiological chimeras. We introduced RT7b fetal liver cells into nonirradiated congenic RT7a neonatal rats. The chimerism 6-20 wk after injection ranged from 0.3 to 20%. The numbers of cell clones simultaneously contributing to cell generation in a particular histological feature were deduced from the variance in donor cell distribution. In bone marrow and thymus, donor-derived lymphoid cells were found scattered among host cells, indicating a high mobility of cells. In bone marrow, donor cells were evenly distributed over the entire marrow, even at low chimerism. This indicates that leukopoiesis is maintained by the proliferation of many clones. In the thymus, the various lobules showed different quantities of donor-derived lymphoid cells. Mathematical analysis of these differences indicated that 17-18 cell division cycles occur in the cortex. In spleen, the distribution of donor-derived cells over the germinal centers indicated that 5 d after antigenic stimulation, germinal centers develop oligoclonally. The main conclusions of this work are that (a) bone marrow and thymus are highly polyclonal; (b) 17-18 divisions occur between prothymocyte and mature T cell; and (c) lymphoid cells disperse rapidly while proliferating and differentiating.
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http://dx.doi.org/10.1084/jem.175.5.1255 | DOI Listing |
Blood Adv
January 2025
Univeristy of Alabama at Birmingham, Birmingham, Alabama, United States.
Hepatosplenic T-cell lymphoma (HSTCL) is an aggressive mature T-cell lymphoma characterized by significant hepatosplenomegaly, bone marrow involvement, and minimal or no lymphadenopathy. Primarily affecting young adults, it is exceptionally rare in children and adolescents. This makes diagnosis and treatment particularly challenging for pathologists and pediatric oncologists.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Pharmacology & Toxicology, The University of Texas Medical Branch, Galveston, Texas, United States of America.
Severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1) and -2 (SARS-CoV-2) are beta-coronaviruses (β-CoVs) that have caused significant morbidity and mortality worldwide. Therefore, a better understanding of host responses to β-CoVs would provide insights into the pathogenesis of these viruses to identify potential targets for medical countermeasures. In this study, our objective is to use a systems biology approach to explore the magnitude and scope of innate immune responses triggered by SARS-CoV-1 and -2 infection over time in pathologically relevant human lung epithelial cells (Calu-3/2B4 cells).
View Article and Find Full Text PDFPLoS One
January 2025
Division of Pharmacology, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
Toll-like receptor (TLRs) activation in multiple myeloma (MM) cells induces heterogeneous functional responses including cell growth and proliferation, survival or apoptosis. These effects have been suggested to be partly due to increase in secretion of cytokines such as IL-6 or IFNα among others from MM cells following TLR activation. However, whether triggering of these receptors also modulates production of immunoglobulin free light chains (FLCs), which largely contribute to MM pathology, has not been investigated in MM cells before.
View Article and Find Full Text PDFAnn Rheum Dis
January 2025
Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA. Electronic address: https://twitter.com/david_felson.
Background: Preventing worsening osteoarthritis (OA) in persons with early OA is a major treatment goal. We evaluated if different early OA definitions yielded enough cases of worsening OA within 2-5 years to make trial testing treatments feasible.
Methods: We assessed different definitions of early OA using data from Multicenter Osteoarthritis (MOST) Study participants who were followed up longitudinally.
Cell Transplant
January 2025
Division of Rheumatology, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
To assess the impact of a single intra-articular (IA) injection of bone marrow-derived mesenchymal stem cells (BM-MSCs) in patients with knee osteoarthritis (OA), a randomized, double-blind, placebo-controlled study was conducted. The study included 24 patients with knee OA who were randomly assigned to receive either a single IA injection of BM-MSCs or normal saline. Changes in the visual analog scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee Injury and Osteoarthritis Outcome Score (KOOS) after IA injection were assessed at 3, 6, 9, and 12 months.
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