Hematopoiesis is orchestrated by interactions between hematopoietic stem/progenitor cells (HSPCs) and stromal cells within bone marrow (BM) niches. Side population (SP) functionality is a major characteristic of HSPCs related to quiescence and resistance to drugs and environmental stresses. At steady state, SP cells are mainly present in the BM and are mostly absent from the circulation except in stress conditions, raising the hypothesis of the versatility of the SP functionality. However, the mechanism of SP phenotype regulation is unclear. Here we show for the first time that the SP functionality can be induced in lin(-) cells from unmobilized peripheral blood after nesting on mesenchymal stromal cells (MSCs). This MSC-induced SP fraction contains HSPCs as demonstrated by their (i) CD34(+) cell percentage, (ii) quiescent status, (iii) in vitro proliferative and clonogenic potential, (iv) engraftment in NSG (NOD SCID gamma chain) mice and (v) stemness gene expression profile. We demonstrate that SP phenotype acquisition/reactivation by circulating lin(-) cells is dependent on interactions with MSCs through VLA-4/α4β1-integrin and CD44. A similar integrin-dependent mechanism of SP phenotype acquisition in acute myeloid leukemia circulating blasts suggests an extrinsic regulation of ATP-binding cassette-transporter activity that could be of importance for a better understanding of adhesion-mediated chemoresistance mechanisms.
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http://dx.doi.org/10.1038/leu.2013.256 | DOI Listing |
PLoS 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 PDFEven though Leydig cell tumor (LCT) represents the most common neoplasia among testicular sex cord-stromal tumors (SCSTs), it is a rare condition, comprising 1-2% of all testicular tumors, with a 10% risk of malignancy most commonly located in retroperitoneal lymph nodes. LCTs may demonstrate various clinical manifestations - from asymptomatic intratesticular swelling through nonspecific symptoms such as loss of libido, impotence or infertility, up to feminizing or virilizing syndromes due to hormonal activity of the tumor. This article presents a case of Leydig cell tumor that was associated with azoospermia what have rarely been reported worldwide.
View Article and Find Full Text PDFRedox Rep
December 2025
Department of Hematology, Shenzhen Qianhai Shekou Pilot Free Trade Zone Hospital, Shenzhen, People's Republic of China.
Background: Regenerative medicine researches have shown that mesenchymal stem cells (MSCs) may be an effective treatment method for premature ovarian insufficiency (POI). However, the efficacy of MSCs is still limited.
Purpose: This study aims to explain whether salidroside and MSCs combination is a therapeutic strategy to POI and to explore salidroside-enhanced MSCs inhibiting ferroptosis via Keap1/Nrf2/GPX4 signaling.
Reproduction
January 2025
H Ka, Biological Science and Technology, Yonsei University - Mirae Campus, Wonju, Korea (the Republic of).
To successfully establish and maintain pregnancy in pigs, a variety of factors must work together at the maternal-conceptus interface to form an immune environment appropriate for both the mother and the conceptus. Our transcriptomics study has shown that cluster of differentiation ligand 40 (CD40L) and its receptor CD40, which are known to play important roles in regulating cell- and antibody-mediated immunity, are expressed in the endometrium during early pregnancy. However, the roles of the CD40L and CD40 signaling system are not well understood.
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