A C-type CpG ODN accelerates wound healing via regulating fibroblasts and immune response

Insight into the role of IRF7 in skin and connective tissue diseases

Interferons (IFNs) are signalling proteins primarily involved in initiating innate immune responses against pathogens and promoting the maturation of immune cells. Interferon Regulatory Factor 7 (IRF7) plays a pivotal role in the IFNs signalling pathway. The activation process of IRF7 is incited by exogenous or abnormal nucleic acids, which is followed by the identification via pattern recognition receptors (PRRs) and the ensuing signalling cascades. Upon activation, IRF7 modulates the expression of both IFNs and inflammatory gene regulation. As a multifunctional transcription factor, IRF7 is mainly expressed in immune cells, yet its presence is also detected in keratinocytes, fibroblasts, and various dermal cell types. In these cells, IRF7 is critical for skin immunity, inflammation, and fibrosis. IRF7 dysregulation may lead to autoimmune and inflammatory skin conditions, including systemic scleroderma (SSc), systemic lupus erythematosus (SLE), Atopic dermatitis (AD) and Psoriasis. This comprehensive review aims to extensively elucidate the role of IRF7 and its signalling pathways in immune cells and keratinocytes, highlighting its significance in skin-related and connective tissue diseases.

Toll-like receptor 9 agonists and combination therapies: strategies to modulate the tumour immune microenvironment for systemic anti-tumour immunity

Over the past decade, tremendous progress has taken place in tumour immunotherapy, relying on the fast development of combination therapy strategies that target multiple immunosuppressive signaling pathways in the immune system of cancer patients to achieve a high response rate in clinical practice. Toll-like receptor 9 (TLR9) agonists have been extensively investigated as therapeutics in monotherapy or combination therapies for the treatment of cancer, infectious diseases and allergies. TLR9 agonists monotherapy shows limited efficacy in cancer patients; whereas, in combination with other therapies including antigen vaccines, radiotherapies, chemotherapies and immunotherapies exhibit great potential. Synthetic unmethylated CpG oligodeoxynucleotide (ODN), a commonly used agonist for TLR9, stimulate various antigen-presenting cells in the tumour microenvironment, which can initiate innate and adaptive immune responses. Novel combination therapy approaches, which co-deliver immunostimulatory CpG-ODN with other therapeutics, have been tested in animal models and early human clinical trials to induce anti-tumour immune responses. In this review, we describe the basic understanding of TLR9 signaling pathway; the delivery methods in most studies; discuss the key challenges of each of the above mentioned TLR9 agonist-based combination immunotherapies and provide an overview of the ongoing clinical trial results from CpG-ODN based combination therapies in cancer patients.

Topical Administration of Heat-Killed Enterococcus faecalis Strain KH2 Promotes Re-Epithelialization and Granulation Tissue Formation during Skin Wound-Healing

Lactic acid bacteria (LAB) are known to have beneficial effects on immune responses when they are orally administered as bacterial products. Although the beneficial effects of LAB have been reported for the genera Lactobacillus and Lactococcus, little has been uncovered on the effects of the genus Enterococcus on skin wound-healing. In this study, we aimed to clarify the effect of heat-killed Enterococcus faecalis KH2 (heat-killed KH2) strain on the wound-healing process and to evaluate the therapeutic potential in chronic skin wounds. We analyzed percent wound closure, re-epithelialization, and granulation area, and cytokine and growth factor production. We found that heat-killed KH2 contributed to the acceleration of re-epithelialization and the formation of granulation tissue by inducing tumor necrosis factor-α, interleukin-6, basic fibroblast growth factor, transforming growth factor (TGF)-β1, and vascular endothelial growth factor production. In addition, heat-killed KH2 also improved wound closure, which was accompanied by the increased production of TGF-β1 in diabetic mice. Topical administration of heat-killed KH2 might have therapeutic potential for the treatment of chronic skin wounds in diabetes mellitus. In the present study, we concluded that heat-killed KH2 promoted skin wound-healing through the formation of granulation tissues and the production of inflammatory cytokines and growth factors.

CpG-Based Nanovaccines for Cancer Immunotherapy

Cancer has been a serious health hazard to the people all over the world with its high incidence and horrible mortality. In recent years, tumor vaccines in immunotherapy have become a hotspot in cancer therapy due to their many practical advantages and good therapeutic potentials. Among the various vaccines, nanovaccine utilized nanoparticles (NPs) as the carrier and/or adjuvant has presented significant therapeutic effect in cancer treatment. For tumor nanovaccines, unmethylated cytosine-phosphate-guanine oligodeoxynucleotide (CpG ODN) is a commonly used adjuvant. It has been reported that CpG ODN was the most effective immune stimulant among the currently known adjuvants. It could be recognized by toll-like receptor 9 (TLR9) to activate humoral and cellular immunity for preventing or treating cancer. In this review, the topic of CpG-based nanovaccines for cancer immunotherapy will be focused. The types and properties of different CpG will be introduced in detail first, and then some representative tumor nanovaccines will be reviewed according to the diverse loading modes of CpG, such as electrostatic adsorption, covalent bonding, hydrophilic and hydrophobic interaction, and DNA self-assembly, for summarizing the current progress of CpG-based tumor nanovaccines. Finally, the challenges and future perspectives will be discussed. It is hoped that this review will provide valuable references for the development of nanovaccines in cancer immunotherapy.

Biomaterials strategies to balance inflammation and tenogenesis for tendon repair

Adult tendon tissue demonstrates a limited regenerative capacity, and the natural repair process leaves fibrotic scar tissue with inferior mechanical properties. Surgical treatment is insufficient to provide the mechanical, structural, and biochemical environment necessary to restore functional tissue. While numerous strategies including biodegradable scaffolds, bioactive factor delivery, and cell-based therapies have been investigated, most studies have focused exclusively on either suppressing inflammation or promoting tenogenesis, which includes tenocyte proliferation, ECM production, and tissue formation. New biomaterials-based approaches represent an opportunity to more effectively balance the two processes and improve regenerative outcomes from tendon injuries. Biomaterials applications that have been explored for tendon regeneration include formation of biodegradable scaffolds presenting topographical, mechanical, and/or immunomodulatory cues conducive to tendon repair; delivery of immunomodulatory or tenogenic biomolecules; and delivery of therapeutic cells such as tenocytes and stem cells. In this review, we provide the biological context for the challenges in tendon repair, discuss biomaterials approaches to modulate the immune and regenerative environment during the healing process, and consider the future development of comprehensive biomaterials-based strategies that can better restore the function of injured tendon. STATEMENT OF SIGNIFICANCE: Current strategies for tendon repair focus on suppressing inflammation or enhancing tenogenesis. Evidence indicates that regulated inflammation is beneficial to tendon healing and that excessive tissue remodeling can cause fibrosis. Thus, it is necessary to adopt an approach that balances the benefits of regulated inflammation and tenogenesis. By reviewing potential treatments involving biodegradable scaffolds, biological cues, and therapeutic cells, we contrast how each strategy promotes or suppresses specific repair steps to improve the healing outcome, and highlight the advantages of a comprehensive approach that facilitates the clearance of necrotic tissue and recruitment of cells during the inflammatory stage, followed by ECM synthesis and organization in the proliferative and remodeling stages with the goal of restoring function to the tendon.

CpG Oligodeoxynucleotides Induces Apoptosis of Human Bladder Cancer Cells via Caspase-3-Bax/Bcl-2-p53 Axis

OBJECTIVE

To evaluate the anti-cancer effect of unmethylated cytosine-phosphorothioate-guanine (CpG)-containing oligodeoxynucleotides (ODNs) on human bladder cancer UM-UC-3 cells, our study was carried out.

METHODS

The viability of cells (UM-UC-3, T24 and SV-HUC-1) with CpG ODN treatments was examined by cell counting kit-8 (CCK-8) assay. Apoptosis and cell cycle phase were determined by flow cytometry analysis. Pre-apoptosis factors of caspase-3, p53, B-cell lymphoma 2 associated X protein (Bax) and anti-apoptosis factor of B-cell lymphoma 2 (Bcl-2) were detected by western blot.

RESULTS

Experimental results showed that the viability of human bladder cancer cells (UM-UC-3 and T24) with CpG ODN treatment was decreased and the viability of human normal urothelial cells (SV-HUC-1) with CpG ODN treatment was increased with time-dependance manner. Moreover, CpG ODN increased the apoptosis rate of UM-UC-3 cells and arrested more cells in G0G1 phase. Furthermore, the expression of caspase-3, p53 and Bax were increased and the expression of Bcl-2 was decreased with CpG ODN treatment on UM-UC-3 cells.

CONCLUSION

CpG ODN promoted the proliferation of normal urinary transitional epithelial cells (SV-HUC-1) and inhibited the cell viability of human bladder cancer cells (UM-UC-3 and T24) in vitro. CpG ODN induced the apoptosis of human bladder cancer (UM-UC-3) cells in a cascade progress via enhancing the expression of caspase-3, p53 and Bax, and inhibiting the expression of Bcl-2 with significant time-dependancy. CpG ODN inhibited cell cycle distribution of human bladder cancer (UM-UC-3) cells with more cells were arrested in G0G1 phase. This study suggested that the CpG ODN is the potential candidate on human bladder cancer.