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Biology subjects

Gonzalez-Romero, D.

Publications and source records attributed to Gonzalez-Romero, D..

2 recordsLinked to original sources

Differential proteomic and metabolic remodelling of CD4⁺ and CD8⁺ T cells in mesenteric lymph nodes during colitis-associated colorectal cancer

Patients with colitis are at elevated risk of developing colitis-associated colorectal cancer (CAC), yet the molecular and metabolic adaptations of T cells during this process remain unclear. Using quantitative mass spectrometry in the AOM/DSS mouse model we mapped proteomic networks of CD4+ and CD8+ T cells in mesenteric lymph nodes across healthy, colitis, and cancer stages. CD4 T cells expanded during CAC progression and underwent extensive proteomic remodelling, including upregulation of DNA replication, cell cycle, ribosome biogenesis, and translation. These changes were accompanied by enhanced glycolysis, TCA activity, mitochondrial mass, and oxidative phosphorylation, indicating a highly metabolically active state. In contrast, CD8 T cells showed minimal changes in cell number, protein content and in metabolic and proteomic remodelling. CD4 T cells progressively acquire inflammatory Th1 and regulatory features, whereas CD8 T cells remained poorly activated. Together, these findings reveal distinct T cell adaptations shaped by CAC and identify potential immunometabolic targets.

immunology↗

p38γ and p38δ modulate innate immune response by regulating MEF2D activation

Evidence implicating p38{gamma} and p38{delta} (p38{gamma}/p38{delta}) in inflammation are mainly based on experiments using p38{gamma}/p38{delta} deficient (p38{gamma}/{delta}-/-) mice, which show low levels of TPL2, the kinase upstream of MKK1-ERK1/2 in myeloid cells. This could obscure p38{gamma}/p38{delta} roles, since TPL2 is essential for regulating inflammation. Here we generated a p38{gamma}D171A/D171A/p38{delta}-/- (p38{gamma}/{delta}KIKO) mouse, expressing kinase-inactive p38{gamma} and lacking p38{delta}. This mouse exhibited normal TPL2 levels, making it an excellent tool to elucidate specific p38{gamma}/p38{delta} functions. p38{gamma}/{delta}KIKO mice showed a reduced inflammatory response and less susceptibility to LPS-induced septic shock and Candida albicans infection than wild-type mice. Gene expression analyses in LPS-activated WT and p38{gamma}/{delta}KIKO macrophages revealed that p38{gamma}/p38{delta} regulated numerous genes implicated in innate immune response. Additionally, phospho-proteomic analyses and in vitro kinase assays showed that the transcription factor myocyte enhancer factor-2D (MEF2D) was phosphorylated at Ser444 via p38{gamma}/p38{delta}. Mutation of MEF2D Ser444 to the non-phosphorylatable residue Ala increased its transcriptional activity and the expression of iNOS and IL-1{beta} mRNA. These results suggest that p38{gamma}/p38{delta} govern innate immune responses by regulating MEF2D phosphorylation and transcriptional activity.

molecular biology↗