Background/purpose: Dendritic cell (DC) migration from tumors to T-cell priming sites is critical in developing antitumor cytotoxicity. Cysteine cysteine receptor 7 (CCR7), a promigratory chemokine receptor, regulates DC recruitment to secondary lymphoid organs. Tumors may inhibit CCR7 expression to evade immunodetection. Previous work implicates impaired DC migration as a critical defect in immunity to neuroblastoma (NB). However, the mechanism has yet to be defined. We hypothesize that NB abrogates DC CCR7 expression and signaling, leading to decreased antitumor immunity.
Methods: A/J mice (N = 36) were injected with saline (control) or murine NB (TBJ) and bone marrow-derived DC were isolated at 7, 14, and 28 days. CCR7 expression was analyzed by polymerase chain reaction, Western blot, and flow cytometry. Cytometry data were analyzed using the paired Student's t test.
Results: Dendritic cells isolated from mice with NB had a 60% increase in CCR7 protein expression by flow cytometry compared with control mice at day 7. However, there was a 43% downregulation of CCR7 expression by DC from tumor-bearing mice compared with controls 2 weeks postinoculation (P < .005). These observations were confirmed by polymerase chain reaction and Western blot analysis.
Conclusion: Neuroblastoma initially upregulates CCR7 expression by DC. However, with tumor progression, this chemokine is downregulated, likely leading to impaired DC migration. Immunotherapeutic strategies to bypass or augment CCR7-dependent DC trafficking may improve survival for patients with aggressive disease.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jpedsurg.2005.03.042 | DOI Listing |
Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection, with resistance to antimalarial drugs, including artemisinin-based combination therapies(ACTs), posing a significant threat. CD4+ naive cells expressing CCR7 are known to play a protective role, as they readily migrate to secondary lymphoid tissues activated by CCL19 chemokines. In an effort to address this challenge, we investigated the impact of Annona muricata, an herbaceous and immunomodulatory plant, on CCL19 concentration.
View Article and Find Full Text PDFBiomedicines
December 2024
Center of Virology Research, Faculty of Human Medicine, University of San Martín de Porres, Lima 15011, Peru.
Background: Chronic kidney disease (CKD) patients often experience dysregulated inflammation, particularly when compounded by comorbidities such as type 2 diabetes (T2D).
Objective: The aim of this study was to determine whether T2D influences the profile of memory T lymphocytes, regulatory T cells (Tregs), and the gene expression of transcription factors such as , , , and in CKD patients.
Methods: Twenty-two CKD patients undergoing hemodialysis were selected for the study.
Int J Parasitol
January 2025
The helminth Trichinella spiralis, through its excretory-secretory (ES L1) products, induces immune regulatory mechanisms that modulate the host's immune response not only to itself, but also to bystander antigens, foreign or self in origin, which can result in the alleviation of inflammatory diseases. Under the influence of ES L1, dendritic cells (DCs) acquire a tolerogenic phenotype and the capacity to induce Th2 and regulatory responses. Since ES L1 products represent a complex mixture of proteins and extracellular vesicles (TsEVs) the aim of this study was to investigate the impact of TsEVs, isolated from ES L1 products, on phenotypic and functional characteristics of DCs and to elucidate whether TsEVs could reproduce the immunomodulatory effects of the complete ES L1 product.
View Article and Find Full Text PDFArthritis Rheumatol
January 2025
Department of Biology and Biotechnologies "Charles Darwin", Sapienza University of Rome, Rome, Italy.
Objective: A pathogenetic role of CD8+ T lymphocytes in radiographic axial spondyloarthritis (r-axSpA) and other spondyloarthritis (SpA) is sustained by genome-wide association studies (GWAS) and by the expansion of public T cell clonotypes in the target tissues. This study investigates the migration of CD8+ T cells, along with their phenotype and functions in patients with r-axSpA and psoriatic arthritis (PsA).
Methods: Peripheral blood CD8+ and CD4+ T cells were isolated from r-axSpA (n= 128), PsA (n= 60) and rheumatoid arthritis (RA, n= 74) patients and healthy donors (HD, n= 79).
Emerg Microbes Infect
January 2025
HIV/AIDS Unit, National Institute for Infectious Diseases "Lazzaro Spallanzani" IRCCS, Rome, Italy.
The first evidence that Orthopoxvirus induced the expansion and the recall of effector innate Vδ2T-cells was described in a macaque model. Although, an engagement of αβ T-cells specific response in patients infected with human monkeypox (Mpox) was demonstrated, little is known about the role of γδ T-cells during Mpox infection. IFN-γ-producing γδ T-cells in the resistance to poxviruses may a key role in inducing a protective type 1 memory immunity.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!