Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA, United States.
Published: August 2021
AI Article Synopsis
Article Abstract
Hematopoietic stem cells (HSCs) are defined by their self-renewal, multipotency, and bone marrow (BM) engraftment abilities. How HSCs emerge during embryonic development remains unclear, but are thought to arise from hemogenic endothelium through an intermediate precursor called "pre-HSCs." Pre-HSCs have self-renewal and multipotent activity, but lack BM engraftability. They can be identified functionally by transplantation into neonatal recipients, or by co-culture with cytokines and stroma followed by transplantation into adult recipients. While pre-HSCs express markers such as Kit and CD144, a precise surface marker identity for pre-HSCs has remained elusive due to the fluctuating expression of common HSC markers during embryonic development. We have previously determined that the lack of CD11a expression distinguishes HSCs in adults as well as multipotent progenitors in the embryo. Here, we use a neonatal transplantation assay to identify pre-HSC populations in the mouse embryo. We establish CD11a as a critical marker for the identification and enrichment of pre-HSCs in day 10.5 and 11.5 mouse embryos. Our proposed pre-HSC population, termed "11a- eKLS" (CD11a- Ter119- CD43+ Kit+ Sca1+ CD144+), contains all long-term engrafting embryonic progenitors. This population also displays a cell-cycle status expected of embryonic HSC precursors. Furthermore, we identify the neonatal liver as the likely source of signals that can mature pre-HSCs into BM-engraftable HSCs.
The immune system undergoes profound dysregulation in sepsis, characterized by hyperinflammation in the acute phase followed by long-lasting immunosuppression. T-cell exhaustion has been proposed as one facet of sepsis-related immunosuppression, which is characterized by impaired effector function and continuous expression of PD1. However, the current analysis of T-cell exhaustion in the post-sepsis is inadequate.
Follicular lymphoma (FL) is the most common low-grade lymphoma. Despite its indolent nature, FL carries an inherent risk of histological transformation (HT) to a more aggressive lymphoma. Existing biomarkers are insufficient to predict HT, indicating the need for more robust biological predictors.
Cluster of Differentiation 54 (CD54), also known as intracellular adhesion molecule-1 (ICAM-1), is a transmembrane glycoprotein belonging to the immunoglobulin superfamily. Although CD54 has been shown to be involved in cell-to-cell adhesion and proliferation of B-cell lymphoma cell lines, the clinical significance of its expression has not yet been elucidated. We analyzed Ki-67 indices, the expression status of CD54 and its receptor (CD11a), and the intercellular distance of tumor cells in 40 diffuse large B-cell lymphoma (DLBCL) cases with vascular invasion to analyze the association of cell adhesion and proliferation status.
* Prolonged stress leads to decreased NK cell numbers and functions across various species, with particular age and stress exposure impacting effectiveness; rehabilitation strategies have shown limited success.
* Differences in stress response are noted between genders, with females showing greater NK cell suppression, and research indicates mice are not ideal models for studying stress effects on NK cells, pointing to the need for further investigation into the mechanisms behind NK cell dysfunction.
Aseptic loosening is a major complication of joint replacement surgery, characterized by periprosthetic osteolysis and chronic inflammation at the bone‑implant interface. Cells release chemokines, cytokines and other pro‑inflammatory substances that perpetuate inflammation reactions, while other particle‑stimulated macrophages promote osteoclastic bone resorption and impair bone formation. The present study investigated integrin and inflammatory cytokine expression patterns in RAW 264.
