The orphan steroid receptor, Nur77, is thought to be a central participant in events leading to TCR-mediated clonal deletion of immature thymocytes. Interestingly, although both immature and mature murine T cell populations rapidly up-regulate Nur77 after TCR stimulation, immature CD4+CD8+ thymocytes respond by undergoing apoptosis, whereas their mature descendants respond by dividing. To understand these developmental differences in susceptibility to the proapoptotic potential of Nur77, we compared its regulation and compartmentalization and show that mature, but not immature, T cells hyperphosphorylate Nur77 in response to TCR signals. Nur77 resides in the nucleus of immature CD4+CD8+ thymocytes throughout the course of its expression and is not found in either the organellar or cytoplasmic fractions. However, hyperphosphorylation of Nur77 in mature T cells, which is mediated by both the MAPK and PI3K/Akt pathways, shifts its localization from the nucleus to the cytoplasm. The failure of immature CD4+CD8+ thymocytes to hyperphosphorylate Nur77 in response to TCR stimulation may be due in part to decreased Akt activity at this developmental stage.

Download full-text PDF

Source
http://dx.doi.org/10.4049/jimmunol.177.10.6660DOI Listing

Publication Analysis

Top Keywords

immature cd4+cd8+
16
cd4+cd8+ thymocytes
16
response tcr
12
tcr stimulation
12
mature cells
8
nur77
8
hyperphosphorylate nur77
8
nur77 response
8
immature
7
thymocytes
5

Similar Publications

Dendritic cells (DCs) are specialized immune cells that play a crucial role in presenting antigens and activating cytotoxic T lymphocytes to combat tumors. The immune checkpoint receptor programmed cell death-1 (PD-1) can bind to its ligand programmed cell death-ligand 1 (PD-L1), which is expressed on the surface of cancer cells. This interaction suppresses T-cell activation and promotes immune tolerance.

View Article and Find Full Text PDF

During thymic development, most γδ T cells acquire innate-like characteristics that are critical for their function in tumor surveillance, infectious disease, and tissue repair. The mechanisms, however, that regulate γδ T cell developmental programming remain unclear. Recently, we demonstrated that the SLAM/SAP signaling pathway regulates the development and function of multiple innate-like γδ T cell subsets.

View Article and Find Full Text PDF

Background: While the prognostic role of tertiary lymphoid structures (TLS) has been well studied in solid cancers, the prevalence and impact of immature precursor lymphoid structures known as lymphoid aggregates (LA) remain unresolved in relation to the disease process. In this study, we examined characteristics and the prognostic utility of LA and TLS status in histological samples from patients with melanoma.

Methods: We assessed The Cancer Genomic Atlas-skin cutaneous melanoma digital slides and melanoma specimens from the University of Pittsburgh for the presence of LA and TLS using H&E staining, multiplex immunofluorescence (mIF) and transcriptomic analyses.

View Article and Find Full Text PDF

In situ endoscopic photodynamic therapy combined with immature DC vaccination induces a robust T cell response against peritoneal carcinomatosis.

J Immunother Cancer

November 2024

Institut de Recherche Expérimentale et Clinique (IREC), Pole of Pharmacology and Therapeutics (FATH), Cancer Translational Research laboratory, UCLouvain, Brussels, Belgium

Background: Immunogenic cell death (ICD) and ferroptosis have recently emerged as key factors in the anticancer immune response. Among the treatments able to induce ICD and the associated release of danger signals is photodynamic therapy (PDT). Ferroptosis for its part results from lipid peroxidation and is induced by CD8 T cells to kill nearby cancer cells on IFN-γ production.

View Article and Find Full Text PDF

Background/objectives: The impact of virion maturation on neutralizing antibody responses in HIV treatment is not fully understood. This study examines whether antiretroviral regimens (ART) with boosted protease inhibitors (b-PI), which increase exposure to immature virions, affect neutralization capacity compared to Non-b-PI regimens.

Methods: Neutralization activity was assessed in 45 HIV-infected individuals on b-PI regimens and 56 on Non-b-PI regimens, adjusting for factors like infection duration, ART initiation, and immune markers.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!