Publications by authors named "Abidin B"

Preserving the balance of metabolic processes in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), is crucial for optimal vascular function and integrity. ECs are metabolically active and depend on aerobic glycolysis to efficiently produce energy for their essential functions, which include regulating vascular tone. Impaired EC metabolism is linked to endothelial damage, increased permeability and inflammation.

View Article and Find Full Text PDF

In the context of inflammation, T cell activation occurs by the concerted signals of the T cell receptor (TCR), co-stimulatory receptors ligation, and a pro-inflammatory cytokine microenvironment. Fine-tuning these signals is crucial to maintain T cell homeostasis and prevent self-reactivity while offering protection against infectious diseases and cancer. Recent developments in understanding the complex crosstalk between the molecular events controlling T cell activation and the balancing regulatory cues offer novel approaches for the development of T cell-based immunotherapies.

View Article and Find Full Text PDF

Thousand-and-one-amino acid kinase 3 (TAOK3) is a serine and threonine kinase that belongs to the STE-20 family of kinases. Its absence reduces T cell receptor (TCR) signaling and increases the interaction of the tyrosine phosphatase SHP-1, a major negative regulator of proximal TCR signaling, with the kinase LCK, a component of the core TCR signaling complex. Here, we used mouse models and human cell lines to investigate the mechanism by which TAOK3 limits the interaction of SHP-1 with LCK.

View Article and Find Full Text PDF

Background: Human aging is characterized by a state of chronic inflammation, termed inflammaging, for which the causes are incompletely understood. It is known, however, that macrophages play a driving role in establishing inflammaging by promoting pro-inflammatory rather than anti-inflammatory responses. Numerous genetic and environmental risk factors have been implicated with inflammaging, most of which are directly linked to pro-inflammatory mediators IL-6, IL1Ra, and TNFα.

View Article and Find Full Text PDF

Emergency hematopoiesis involves the activation of bone marrow hematopoietic stem/progenitor cells (HSPCs) in response to systemic inflammation by a combination of cell-autonomous and stroma-dependent signals and leads to their release from bone marrow and migration to periphery. We have previously shown that FZD6 plays a pivotal role in regulating HSPC expansion and long-term maintenance. Now we sought to better understand the underlying mechanisms.

View Article and Find Full Text PDF

Although intracellular Wnt signaling pathways need to be tightly regulated to promote hematopoietic stem cell self-renewal, the source and identity of important Wnt ligands in the bone marrow is still largely unknown. The noncanonical ligand Wnt4 is expressed in the bone marrow as well as in the stroma, and its overexpression in fetal liver cells facilitates thymic recovery; however, its impact on adult hematopoietic stem cell function remains unclear. Here, we report that the deletion of Wnt4 from hematopoietic cells in mice (Wnt4 ) resulted in decreased lymphopoiesis at steady state.

View Article and Find Full Text PDF
Article Synopsis
  • Inflammation plays a dual role by fighting infections and contributing to chronic diseases, as seen with Leishmania donovani, which causes visceral leishmaniasis and triggers strong inflammatory responses leading to immune suppression.
  • HIF-1α, activated in low-oxygen inflamed tissues, inhibits IL-12 production in dendritic cells, which limits the development of protective Th1 responses against Leishmania.
  • Deleting HIF-1α in specific immune cells enhances IL-12 levels and Th1 cell activity, resulting in lower parasite loads, suggesting that targeting HIF-1α might be a promising treatment strategy for persistent Leishmania infections.
View Article and Find Full Text PDF

Leishmania donovani is known to induce myelopoiesis and to dramatically increase extramedullary myelopoiesis. This results in splenomegaly, which is then accompanied by disruption of the splenic microarchitecture, a chronic inflammatory environment, and immunosuppression. Chronically inflamed tissues are typically hypoxic.

View Article and Find Full Text PDF

Cells of the immune system are derived from hematopoietic stem cells (HSCs) residing in the bone marrow. HSCs become activated in response to stress, such as acute infections, which adapt the bone marrow output to the needs of the immune response. However, the impact of infection-adapted HSC activation and differentiation on the persistence of chronic infections is poorly understood.

View Article and Find Full Text PDF

Adult hematopoietic stem/progenitor cell (HSPC) numbers remain stable in the absence of external stressors. After bone marrow (BM) transplant, HSPCs need to expand substantially to repopulate the BM and replenish the peripheral blood cell pool. In this study, we show that a noncanonical Wnt receptor, Frizzled-6 (Fzd6), regulates HSPC expansion and survival in a hematopoietic cell-intrinsic manner.

View Article and Find Full Text PDF

Purpose: The presence of hypoxic cells in solid tumors is generally considered as a limiting factor for the complete control of tumors by radiation therapy. Pentoxifylline is a methylxanthine derivative that produces hemorrheologic effects which increase tissue oxygen levels. In this study we aimed to determine whether pentoxifylline would enhance the radiation response of Ehlrich mammary carcinoma in mice.

View Article and Find Full Text PDF

Thirty-day experiments on white male rats were carried out to determine the combined effect of carbon monoxide and hyperoxic atmosphere on the animal body. The two factors showed an antagonistic biological effect, the influence of hyperoxic atmosphere prevailing over that of carbon monoxide. It is suggested that during a combined exposure of animals to the two factors maximally allowable concentrations of each can be used without any corrections.

View Article and Find Full Text PDF

It has been shown experimentally that a 30-day exposure of white rats to hypokinesia and moderate hyperoxia decreases elimination of ammonia and increases the formation and release into an enclosed atmosphere of carbon monoxide, aldehydes and ketones. The level of metabolism of prophyrin and nitrogen containing compounds as well as of fats and carbohydrates is higher during a combined effect of hypokinesia and moderate hyperoxia than during their separate influences.

View Article and Find Full Text PDF