Synthetic oligodeoxynucleotides containing unmethylated CpG motifs activate Toll-Like Receptor 9 (TLR9). Our previous studies have shown the role of hydrogen-bond donor and acceptor groups of cytosine and guanine in the CpG motif and identified synthetic immunostimulatory motifs. In the present study to elucidate the significance of N3-position of cytosine and N1-position of guanine in the CpG motif, we substituted C or G of a CpG dinucleotide with N3-Me-cytosine or N1-Me-guanine, respectively, in immunomodulatory oligodeoxynucleotides (IMOs). IMOs containing N-Me-cytosine or N-Me-guanine in C- or G-position, respectively, of the CpG dinucleotide showed activation of HEK293 cells expressing TLR9, but not TLR3, 7 or 8. IMOs containing N-Me-cytosine or N-Me-guanine modification showed activity in mouse spleen cell cultures, in vivo in mice, and in human cell cultures. In addition, IMOs containing N-Me-substitutions reversed antigen-induced Th2 immune responses towards a Th1-type in OVA-sensitized mouse spleen cell cultures. These studies suggest that TLR9 tolerates a methyl group at N1-position of G and a methyl group at N3-position of C may interfere with TLR9 activation to some extent. These are the first studies elucidating the role of N3-position of cytosine and N1-position of guanine in a CpG motif for TLR9 activation and immune stimulation.
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http://dx.doi.org/10.1093/nar/gkl430 | DOI Listing |
J Thromb Haemost
January 2025
Dalla Lana School of Public Health, University of Toronto, Toronto, Canada; Office of the Vice-Principal of Research and Innovation, University of Toronto Mississauga, Mississauga, Canada. Electronic address:
Background: Whether to stop oral anticoagulants after a first unprovoked venous thromboembolism (VTE) is challenging, partially due to an intriguingly higher risk of VTE recurrence (rVTE) in men after therapy discontinuation. DNA methylation (DNAm) differences between men and women might underly this sex-biased rVTE risk difference.
Aim: To investigate sex-specific associations between DNAm at cytosine-phosphate-guanine (CpG) sites and rVTE.
J Transl Med
January 2025
Department of Epidemiology and Health Statistics, The School of Public Health of Qingdao University, 308 Ningxia Road, Qingdao, 266071, Shandong, People's Republic of China.
Background: DNA methylation (DNAm) has been shown in multiple studies to be associated with the estimated glomerular filtration rate (eGFR). However, studies focusing on Chinese populations are lacking. We conducted an epigenome-wide association study to investigate the association between DNAm and eGFR in Chinese monozygotic twins.
View Article and Find Full Text PDFAdv Mater
January 2025
State Key Laboratory of Systems Medicine for Cancer, Shanghai Cancer Institute. Ren Ji Hospital School of Medicine, Shanghai Jiao Tong University, Shanghai, 200032, P. R. China.
Hypoxia severely limits the antitumor immunotherapy for breast cancer. Although efforts to alleviate tumor hypoxia and drug delivery using diverse nanostructures achieve promising results, the creation of a versatile controllable oxygen-releasing nano-platform for co-delivery with immunostimulatory molecules remains a persistent challenge. To address this problem, a versatile oxygen controllable releasing vehicle PFOB@F127@PDA (PFPNPs) is developed, which effectively co-delivered either protein drug lactate oxidase (LOX) or nucleic acids drug unmethylated cytosine-phosphate-guanine oligonucleotide (CpG ODNs).
View Article and Find Full Text PDFEpigenomics
January 2025
NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
Aim: We aim to assess association of DNA methylation (DNAm) at birth with total immunoglobulin E (IgE) trajectories from birth to late adolescence and whether such association is ethnicity-specific.
Methods: We examined the association of total IgE trajectories from birth to late adolescence with DNAm at birth in two independent birth cohorts, the Isle of wight birth cohort (IOWBC) in UK ( = 796; White) and the maternal and infant cohort study (MICS) in Taiwan ( = 60; Asian). Biological pathways and methylation quantitative trait loci (methQTL) for associated Cytosine-phosphate-Guanine sites were studied.
Mater Today Bio
February 2025
Hebei Key Laboratory of Applied Chemistry, Hebei Key Laboratory of Nanobiotechnology, Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Yanshan University, Qinhuangdao, 066004, China.
Immunotherapy is a cornerstone in cancer treatment, celebrated for its precision, ability to eliminate residual cancer cells, and potential to avert tumor recurrence. Nonetheless, its effectiveness is frequently undermined by the immunosuppressive milieu created by tumors. This study presents a novel nanogel-based drug delivery system, DOX-4PI@CpG@Lipo@Gel (DPCLG), engineered to respond to Matrix Metallopeptidase-2 (MMP-2)-a protease abundant in the tumor microenvironment (TME).
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