Publications by authors named "Christina Giannouli"

Background: Pre-neutrophils, while developing in the bone marrow, transcribe the gene and synthesize Activin-A protein, which they store and release at the earliest stage of their activation in the periphery. However, the role of neutrophil-derived Activin-A is not completely understood.

Methods: To address this issue, we developed a neutrophil-specific Activin-A-deficient animal model ( mice) and analyzed the immune response to Influenza A virus (IAV) infection.

View Article and Find Full Text PDF

Current understanding of Multiple Sclerosis (MS) pathophysiology implicates perturbations in adaptive cellular immune responses, predominantly T cells, in Relapsing-Remitting forms (RRMS). Nevertheless, from a clinical perspective MS is a heterogeneous disease reflecting the heterogeneity of involved biological systems. This complexity requires advanced analysis tools at the single-cell level to discover biomarkers for better patient-group stratification.

View Article and Find Full Text PDF
Article Synopsis
  • NADPH oxidase deficiency worsens lupus conditions in mouse models and humans, but the exact reasons are unclear.
  • Researchers believed that NADPH oxidase helps control autoimmunity by aiding in the cleanup of dead cells, but experiments showed that removing RUBICON, a key protein in this process, led to better outcomes rather than worsening them.
  • The findings suggest that RUBICON plays a unique role in regulating systemic lupus erythematosus (SLE) potentially through B cells, indicating that the expected involvement of the LAP pathway in lupus may not be accurate.
View Article and Find Full Text PDF

Metabolism comprises of two axes in order to serve homeostasis: anabolism and catabolism. Both axes are interbranched with the so-called bioenergetics aspect of metabolism. There is a plethora of analytical biochemical methods to monitor metabolites and reactions in lysates, yet there is a rising need to monitor, quantify and elucidate in real time the spatiotemporal orchestration of complex biochemical reactions in living systems and furthermore to analyze the metabolic effect of chemical compounds that are destined for the clinic.

View Article and Find Full Text PDF

Sphingosine-1-phosphate (S1P) is a bioactive lipid that provides cellular signals through plasma membrane G protein-coupled receptors. The S1P receptor signaling system has a fundamental and widespread function in licensing the exit and release of hematopoietically derived cells from various tissues into the circulation. Although the outlines of the mechanism have been established through genetic and pharmacologic perturbations, the temporal and spatial dynamics of the cellular events involved have been unclear.

View Article and Find Full Text PDF

Ataxia-Telangiectasia and Rad3 related kinase (ATR) is a major gatekeeper of genomic stability and has been the subject of exhaustive study in the context of cell cycle progression and senescence as a DNA damage-induced response. Conditional knockout of the kinase in adult mice results in accelerated aging phenomena, such as such hair graying, alopecia, kyphosis, osteoporosis, thymic involution, fibrosis, and other abnormalities. In addition to that, recent reports strongly implicate signaling mediated by this kinase in the regulation of alternative splicing of certain, mostly cancer-associated transcripts.

View Article and Find Full Text PDF
Article Synopsis
  • Transforming growth factor-beta (TGF-beta) has differing effects on cell proliferation based on cell type, inhibiting epithelial and endothelial cells while stimulating mesenchymal cells like fibroblasts.
  • In fetal fibroblasts, TGF-beta inhibits growth by activating Protein Kinase A (PKA) and increasing cyclin-dependent kinase inhibitors, while in adult fibroblasts it promotes growth through the MEK-ERK pathway without PKA activation.
  • The study highlights how TGF-beta's effects vary between fetal and adult fibroblasts, emphasizing distinct signaling mechanisms that could explain its complex role in cell proliferation overall.
View Article and Find Full Text PDF

Since pronounced differences exist between the fetal and adult repair processes, we studied the proliferative response of skin fibroblasts from these two stages to transforming growth factor-beta (TGF-beta), a cytokine with a broad range of activities in tissue repair. Here, we present evidence that TGF-beta inhibits fetal human skin fibroblasts, while it is stimulatory for adult ones. This proliferative effect of TGF-beta was found to be concentration- dependent, but isoform-independent.

View Article and Find Full Text PDF

Background: The ultimate success of cancer vaccination is primarily dependent upon the generation of tumour-specific CTLs. Protein-based vaccination, while safe, poorly elicits such CTL responses. As fusion of an antigen to the HIV-1 Tat transduction domain was reported to increase MHC class I presentation and CTL responses in vitro, we tested the potency of this approach to augment tumour-directed responses.

View Article and Find Full Text PDF