Regulation of Dendritic Cell Functions by Vitamins as Promising Therapeutic Strategy for Immune System Disorders

Docetaxel treatment together with CTLA-4 knockdown enhances reduction of cell viability and amplifies apoptosis stimulation of MCF-7 breast cancer cells

Breast cancer is the most frequent cancer in women with a 20% mortality rate. The fate of patients suffering from breast cancer can be influenced by immune cells and tumor cells interaction in the tumor microenvironment (TME). Immune checkpoints such as Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) are regulators of the immune system and defend normal tissues from immune cell attacks but they can be expressed in breast cancer tissue and facilitate immune evasion of tumoral cells. Based on this, here we studied the role of CTLA-4 silencing by specific siRNA in MCF-7 breast cancer cell line together with Docetaxel treatment which is one of the robust chemotherapy agents to demonstrate the significance of combining chemotherapy with efficient targeted therapy in tumor regression. The MCF-7 breast cancer cell line was transfected with CTLA-4-siRNA through the electroporation method, then received an appropriate dose of Docetaxel determined by MTT assay. Flow cytometry was utilized to investigate the consequence of simultaneous CTLA-4 gene silencing and Docetaxel treatment on the apoptosis and cell cycle of MCF-7 cells. The expression levels of Bax and Bcl-2 were also investigated using quantitative real-time PCR. Compared to control groups, CTLA-4-suppressed and Docetaxel-treated cells became more susceptible to apoptosis and cell cycle arrest at the G2-M phase. The additive effect of CTLA-4 knockdown together with Docetaxel treatment significantly downregulated BCL-2 level and upregulated BAX expression. Our findings support the idea that combining chemotherapy such as Docetaxel with efficient targeted therapy against inhibitory immune checkpoints can be a promising strategy in cancer treatment.

Altered miR-10a gene expression in peripheral blood mononuclear cells correlates with frequency of T regulatory cells and cytokine profile in multiple sclerosis patients

A critical component in triggering and progressing autoimmune multiple sclerosis (MS) is the deregulation of immune responses, including dysfunction of T regulatory cells (Tregs), critical participants in the pathogenetic context of inflammation. It has been found that miRNAs have a crucial role in the induction of MS because dysregulation of miRNAs can result in defects in immunological tolerance. In this investigation, we examined the miR-10a contribution to MS disorder by comparing the altered expression of miR-10a in peripheral blood mononuclear cells (PBMCs) of 40 MS patients to 40 healthy controls. Additionally, we examined Tregs' frequency in MS patients in compare with healthy controls. We evaluated the secreted levels of anti-inflammatory cytokines, such as IL-10 and TGF-B, in the serum of MS patients and their expression level in healthy controls' and patients' peripheral blood mononuclear cells (PBMCs). Then, we assessed the correlation between miR-10a expression with Treg frequency and levels of anti-inflammatory cytokines in serum. PBMCs from MS patients had downregulated expression of miR-10a, and a substantial correlation was found between this expression and a reduction in Treg cells' frequency and the secreted anti-inflammatory cytokines associated with Tregs' diminished functionality. In summary, our research demonstrated a strong correlation between Tregs' frequency, lower levels of cytokines linked to Treg function, and lower expression of miR-10a in PBMCs. So, the alteration of miR-10a can be utilized as a probable therapeutic target for the prevention and management of MS disorder. However, further examination is requisite before this strategy become practical for use in the clinical setting.

Micro nutrients as immunomodulators in the ageing population: a focus on inflammation and autoimmunity

Immunosenescence, the slow degradation of immune function over time that is a hallmark and driver of aging, makes older people much more likely to be killed by common infections (such as flu) than young adults, but it also contributes greatly to rates of chronic inflammation in later life. Such micro nutrients are crucial for modulating effective immune responses and their deficiencies have been associated with dysfunctional immunity in the elderly. In this review, we specifically focused on the contribution of major micro nutrients (Vitamins A, D and E, Vitamin C; Zinc and Selenium) as immunomodulators in ageing population especially related to inflame-ageing process including autoimmunity. This review will cover these hologenomic interactions, including how micro nutrients can modulate immune cell function and/or cytokine production to benefit their hosts with healthy mucous-associated immunity along with a sustainable immunologic homeostasis. For example, it points out the modulatory effects of vitamin D on both innate and adaptive immunity, with a specific focus on its ability to suppress pro-inflammatory cytokines synthesis while enhancing regulatory T-cell function. In the same context, also zinc is described as important nutrient for thymic function and T-cell differentiation but exhibits immunomodulatory functions by decreasing inflammation. In addition, the review will go over how micro nutrient deficiencies increase systemic chronic low-grade inflammation and, inflammaging as well as actually enhance autoimmune pathologies in old age. It assesses the potential role of additional targeted nutritional supplementation with micro nutrients to counteract these effects, promoting wider immune resilience in older adults. This review collates the current evidence and highlights the role of adequate micro nutrient intake on inflammation and autoimmunity during ageing, providing plausible origins for nutritional interventions to promote healthy immune aging.

RAD001-mediated mTOR targeting in human monocyte-derived dendritic cells shifts them toward an immunogenic phenotype

Dendritic cells (DCs) are essential for promoting T lymphocyte responses since they are specialist antigen-presenting cells. In order to maintain tolerance or initiate immune responses, DCs must be activated in a balanced and regulated manner via diverse signaling pathways. By using a variety of pharmacological components, we can interfere with their different signaling pathways such as the mammalian target of rapamycin (mTOR) to appropriately modulate DC activity. In the current study, we administered RAD001 to DCs to examine the impact of mTOR inhibition on both the maturation stage and the expression of inflammatory and anti-inflammatory molecules in DCs. Pure monocytes were cultivated and stimulated with GM-CSF and IL-4 to generate immature DCs, which were then treated with RAD001. The phenotype of the DCs was determined by labeling surface markers and analyzing them using flow cytometry. Afterward, real-time PCR was carried out to evaluate the expression of inflammatory and anti-inflammatory genes. The administration of RAD001 to DCs led to a significant upregulation in the gene expression of inflammatory molecules such as IL-12, IL-1β, tumor necrosis factor (TNF)-α, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB). Conversely, RAD001 treatment resulted in a decrease in the gene expression of anti-inflammatory factors IL-10 and indoleamine 2,3-dioxygenase (IDO). However, the expression of differentiation and antigen presentation-related markers CD11c and human leukocyte antigens (HLA)-DR in RAD001-treated DCs was lower and higher compared to the control group that did not receive the treatment, respectively. Taken together, our findings indicated that RAD001 treatment of DCs can be a promising therapeutic approach for the generation of immunogenic DCs in order to barricade tumor growth. However, there is a need for further investigation to evaluate the impacts of mTOR inhibition by RAD001 in DCs on cellular immune responses in vitro and in vivo.

Unmasking the NLRP3 inflammasome in dendritic cells as a potential therapeutic target for autoimmunity, cancer, and infectious conditions

Proper and functional immune response requires a complex interaction between innate and adaptive immune cells, which dendritic cells (DCs) are the primary actors in this coordination as professional antigen-presenting cells. DCs are armed with numerous pattern recognition receptors (PRRs) such as nucleotide-binding and oligomerization domain-like receptors (NLRs) like NLRP3, which influence the development of their activation state upon sensation of ligands. NLRP3 is a crucial component of the immune system for protection against tumors and infectious agents, because its activation leads to the assembly of inflammasomes that cause the formation of active caspase-1 and stimulate the maturation and release of proinflammatory cytokines. But, when NLRP3 becomes overactivated, it plays a pathogenic role in the progression of several autoimmune disorders. So, NLRP3 activation is strictly regulated by diverse signaling pathways that are mentioned in detail in this review. Furthermore, the role of NLRP3 in all of the diverse immune cells' subsets is briefly mentioned in this study because NLRP3 plays a pivotal role in modulating other immune cells which are accompanied by DCs' responses and subsequently influence differentiation of T cells to diverse T helper subsets and even impact on cytotoxic CD8+ T cells' responses. This review sheds light on the functional and therapeutic role of NLRP3 in DCs and its contribution to the occurrence and progression of autoimmune disorders, prevention of diverse tumors' development, and recognition and annihilation of various infectious agents. Furthermore, we highlight NLRP3 targeting potential for improving DC-based immunotherapeutic approaches, to be used for the benefit of patients suffering from these disorders.

Bone Formation and Maintenance in Oral Surgery: The Decisive Role of the Immune System-A Narrative Review of Mechanisms and Solutions

Based on the evidence of a significant communication and connection pathway between the bone and immune systems, a new science has emerged: osteoimmunology. Indeed, the immune system has a considerable impact on bone health and diseases, as well as on bone formation during grafts and its stability over time. Chronic inflammation induces the excessive production of oxidants. An imbalance between the levels of oxidants and antioxidants is called oxidative stress. This physio-pathological state causes both molecular and cellular damage, which leads to DNA alterations, genetic mutations and cell apoptosis, and thus, impaired immunity followed by delayed or compromised wound healing. Oxidative stress levels experienced by the body affect bone regeneration and maintenance around teeth and dental implants. As the immune system and bone remodeling are interconnected, bone loss is a consequence of immune dysregulation. Therefore, oral tissue deficiencies such as periodontitis and peri-implantitis should be regarded as immune diseases. Bone management strategies should include both biological and surgical solutions. These protocols tend to improve immunity through antioxidant production to enhance bone formation and prevent bone loss. This narrative review aims to highlight the relationship between inflammation, oxidation, immunity and bone health in the oral cavity. It intends to help clinicians to detect high-risk situations in oral surgery and to propose biological and clinical solutions that will enhance patients' immune responses and surgical treatment outcomes.

Glyburide-treated human monocyte-derived dendritic cells loaded with insulin represent tolerogenic features with anti-inflammatory responses and modulate autologous T cell responses in vitro

Tolerogenic dendritic cells (TolDCs) are attractive therapeutic options for autoimmune disorders because they suppress autologous T-cell responses. Dendritic cells (DCs) are equipped with pattern recognition receptors (PRR), including nucleotide-binding and oligomerization domain-like receptors (NLRs) such as NLRP3. Abnormal NLRP3 activation has been reported to be correlated with the occurrence of autoimmune disorders. Accordingly, we hypothesized that glyburide treatment of DCs by blocking the ATP-sensitive K+ (kATP) channels generates TolDCs by inhibiting NLRP3. Insulin was even loaded on a group of glyburide-treated mature DCs (mDCs) to investigate the antigen (Ag) loading effects on glyburide-treated mDCs' phenotypical and functional features. Consequently, T lymphocytes' mediated responses ensuing co-culture of them with control mDCs, insulin loaded and unloaded glyburide treated mDCs were evaluated to determine generated TolDCs' capacity in inhibition of T cell responses that are inducer of destruction in insulin-producing pancreatic beta cells in Type 1 Diabetes Mellitus (T1DM). Our findings indicated that glyburide generates desirable TolDCs with decreased surface expression of maturation and Ag presentation related markers and diminished level of inflammatory but increased level of anti-inflammatory cytokines, which even insulin loading demonstrated more anti-inflammatory functions. In addition, co-cultured T cells showed regulatory or T helper 2 phenotype instead of T helper 1 features. Our findings suggested that insulin-loaded and unloaded glyburide-treated DCs are promising therapeutic approaches for autoimmune patients, specifically DCs loaded with insulin for T1DM patients. However, further research is required before this technique can be applied in clinical practice.