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Berghe, W. V.

Publications and source records attributed to Berghe, W. V..

3 recordsLinked to original sources

The T cell receptor repertoire captures healthy aging and CMV independently from epigenetic clocks

Human aging is the process through which numerous biological changes occur during life, affecting various processes. In some elderly individuals, this functional decline becomes more pronounced, leading to frailty, a condition characterised by reduced physiological reserves and increased vulnerability to stress. With the global rise of life expectancy, identification of biomarkers for healthspan and frailty are becoming more important. In this study, we directly compare two molecular readouts, namely the T cell receptor (TCR) repertoire and epigenetic clocks, on their ability to discern healthy aging. On blood samples from sixteen individuals, across age-matched healthy elderly and frail individuals, both TCR sequencing and epigenetic profiling were performed. A significantly higher TCR repertoire diversity in the CD4+ T cells differentiated the healthy elderly individuals from the frailty ones. Epigenetic clock signatures of biological relative to chronological ageing rate, did not show a clear difference between both groups. However, when taking into account the CMV-serostatus, a significant increase in epigenetic aging could be observed in the CMV-seropositive individuals. Our results support a clear hypothesis on the role of CMV infection in the healthy aging of the immune system. In healthy elderly, CMV is typically controlled by CD4+ T cells, however, in the frail elderly, the burden of managing the infection shifts to the CD8+ T cells. This change is marked by two key changes: a decrease in TCR diversity for seropositive individuals compared to seronegative individuals, as well as an increase in the fraction of CMV-associated TCRs within the CD8+ T cells. These findings contribute to our understanding of aging and provide insight into how CMV-infection may affect healthy aging and frailty. They also underline the crucial role of the immune system in healthy aging and the value of further investigating ageing-related health/disease patterns in the TCR repertoire to determine healthspan/lifespan.

immunology↗

Investigating the Role of Chromatin Remodeler FOXA1 in Ferroptotic Cell Death

Ferroptosis is a lipid peroxidation-dependent mechanism of regulated cell death known to suppress tumor proliferation and progression. Although several genetic and protein hallmarks have been identified in ferroptotic cell death, it remains challenging to fully characterize ferroptosis signaling pathways and to find suitable biomarkers. Moreover, changes taking place in the epigenome of ferroptotic cells remain poorly studied. In this context, we aimed to investigate the role of chromatin remodeler forkhead box protein A1 (FOXA1) in RSL3-treated multiple myeloma cells because, similar to ferroptosis, this transcription factor has been associated with changes in the lipid metabolism, DNA damage, and epithelial-to-mesenchymal transition (EMT). RNA sequencing and Western blot analysis revealed that FOXA1 expression is consistently upregulated upon ferroptosis induction in different in vitro and in vivo disease models. In silico motif analysis and transcription factor enrichment analysis further suggested that ferroptosis-mediated FOXA1 expression is orchestrated by specificity protein 1 (Sp1), a transcription factor known to be influenced by lipid peroxidation. Remarkably, FOXA1 upregulation in ferroptotic myeloma cells did not alter hormone signaling or EMT, two key downstream signaling pathways of FOXA1. CUT&RUN genome-wide transcriptional binding site profiling showed that GPX4-inhibition by RSL3 triggered loss of binding of FOXA1 to pericentromeric regions in multiple myeloma cells, suggesting that this transcription factor is possibly involved in genomic instability, DNA damage, or cellular senescence under ferroptotic conditions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=152 SRC="FIGDIR/small/461056v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@1fe44acorg.highwire.dtl.DTLVardef@4ea970org.highwire.dtl.DTLVardef@560fd0org.highwire.dtl.DTLVardef@283874_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Withaferin A inhibits LFA-1-stimulated ZAP70 activity and T-cell motility

Here we report that a steroidal lactone withaferin A (WFA) can inhibit T-cell motility, which is crucial for adaptive immune responses as well as autoimmune reactions. Tandem mass spectrometry identified WFA-interactome in human T-cells that were stimulated to migrate via cross-linking of the lymphocyte function-associated antigen-1 (LFA-1) integrin with the ligand intercellular adhesion receptor 1 (ICAM-1). Data revealed significant enrichment of the zeta-chain-associated protein kinase 70 (ZAP70) and cytoskeletal actin protein interaction networks. Phospho-peptide mapping and kinome analysis substantiated kinase signaling downstream of ZAP70 and cytoskeletal kinase pathways as key WFA targets, which was further confirmed by in silico analysis and molecular assays. The WFA-ZAP70 complex was disrupted by a redox agent dithiothreitol, suggesting a covalent binding interface. Moreover, WFA ablated the phosphorylation of the myosin light chain, further constraining T-cell motility. These studies identify a mechanism whereby WFA can impact T-cell motility. WFA can therefore be exploited to pharmacologically controlling host immune responses and preventing autoimmune-mediated pathologies.

immunology↗