Anandamide modulation of monocyte-derived Langerhans cells: implications for immune homeostasis and skin inflammation.

Introduction: The endocannabinoid system (ECS), named after the chemical compounds found in the cannabis plant, is a regulatory network of neurotransmitters, receptors, and enzymes that plays crucial roles in skin health and disease. Endogenous ligands of the ECS, called endocannabinoids, have proven to be important regulators of immune responses. One of the most prevalent endocannabinoids, arachidonoylethanolamide (also known as anandamide), is known for its anti-inflammatory effects. Langerhans cells (LCs) are the sole antigen-presenting cells present in the human epidermis. They serve as the first line of defense against pathogens and are essential for the skin's specific immune responses and play a critical role in maintaining tissue homeostasis; however, little is known about the effect of endocannabinoids on these cells. Our research aimed to provide the connection between monocyte-derived Langerhans cells (moLCs) and the ECS, shedding light on their collaborative roles in immune homeostasis and inflammation. Methods: Human monocytes were differentiated into moLCs using established protocols. Anandamide was applied during the differentiation process to test its effect on the viability, marker expression, and cytokine production of the cells, as well as in short term treatments for intracellular calcium measurement. TLR ligands applied after the differentiation protocol were used to activate moLCs. The impact of anandamide on the functionality of moLCs was further assessed using differential gene expression analysis of bulk RNA-Seq data, moLC-T cell cocultures, while ELISpot was employed to determine polarization of T cells activated in the aforementioned cocultures. Results: Anandamide did not significantly affect the viability of moLCs up to 10 µM. When applied during the differentiation process it had only a negligible effect on CD207 expression, the prototypic marker of LCs; however, there was an observed reduction in CD1a expression by moLCs. Anandamide had no significant effects on the maturation status of moLCs, nor did it affect the maturation induced by TLR3 and TLR7/8 agonists. MoLCs differentiated in the presence of anandamide did however show decreased production of CXCL8, IL-6, IL-10 and IL-12 cytokines induced by TLR3 and TLR7/8 activation. Anandamide-treated moLCs showed an increased capability to activate naïve T cells; however, not to the level seen with combined TLR agonism. RNA sequencing analysis of moLCs differentiated with anandamide showed modest changes compared to control cells but did reveal an inhibitory effect on oxidative phosphorylation specifically in activated moLCs. Anandamide also promoted the polarization of naïve T cells towards a Th1 phenotype. Discussion: Our results show that anandamide has nuanced effects on the differentiation, maturation, cytokine secretion, metabolism and function of activated moLCs. Among these changes the decrease in CD1a expression on moLCs holds promise to selectively dampen inflammation induced by CD1a restricted T cells, which have been implicated as drivers of inflammation in common inflammatory skin conditions such as psoriasis, atopic dermatitis and contact dermatitis.

Trends in the dose-response relationship between adverse childhood experiences and maladaptive metacognitive beliefs: A cross-sectional study.

BACKGROUND: Since the publication of the major research on adverse childhood experiences (ACE) at the turn of the millennium, our knowledge about the prevalence and physical and mental consequences of childhood adversities has increased substantially. In parallel, research on metacognition, which plays an important role in understanding our mental functioning, has also been on the rise. Although the adverse effects of ACEs on mental processes and the role of metacognitive deficits in the development of mental disorders are widely known, hardly any research into the interaction between these two areas has been conducted; this is what triggered our investigation. METHODS: Our research was carried out as a cross-sectional study on a sample of 304 members of the general population. We measured ACEs with the 10-item Adverse Childhood Experiences Questionnaire and maladaptive metacognitions-positive and negative metacognitive beliefs, cognitive confidence, cognitive self-consciousness, and need to control thoughts- using the Meta-Cognitions Questionnaire. The closeness of the relationship between the ACE score and metacognitions was measured using Pearson's linear correlation coefficient, while the association of ACE accumulation with metacognitive beliefs was assessed using generalized linear models. RESULTS: The most common ACE in our sample turned out to be emotional neglect (44.74%). All the examined maladaptive metacognitive beliefs correlate mildly to moderately with the number of suffered ACEs (r = 0.13-0.34), with an increase in the ACE score leading to a rise in the salience of maladaptive metacognitive beliefs. Moreover, a dose-response relationship was seen between increases in ACE scores and the overall values of metacognition, negative metacognitive beliefs, and the maladaptive metacognitive belief of the need to control thoughts. CONCLUSIONS: Our results suggest that the more ACEs were experienced in childhood, the more pronounced the dysfunctional metacognitive beliefs are. Therefore, our findings emphasize the importance of further research into the topic.

The dual role of cannabidiol on monocyte-derived dendritic cell differentiation and maturation.

Introduction: Extracts and compounds isolated from hemp (Cannabis sativa) are increasingly gaining popularity in the treatment of a number of diseases, with topical formulations for dermatological conditions leading the way. Phytocannabinoids such as ( )-cannabidiol, ( )-cannabinol and ( )-Δ9-tetrahydrocannabivarin (CBD, CBN, and THCV, respectively), are present in variable amounts in the plant, and have been shown to have mostly anti-inflammatory effects both in vitro and in vivo, albeit dominantly in murine models. The role of phytocannabinoids in regulating responses of dendritic cells (DCs) remains unclear. Methods: Our research aimed to investigate the effects of CBD, CBN, and THCV on human DCs differentiated from monocytes (moDCs). moDCs were treated with up to 10 µM of each phytocannabinoid, and their effects on viability, differentiation, and maturation were assessed both alone, and in conjunction with TLR agonists. The effects of CBD on cytokine production, T cell activation and polarization as well as the transcriptome of moDCs was also determined. Results: Phytocannabinoids did not influence the viability of moDCs up to 10 µM, and only CBD had effects on maturational markers of moDCs, and neither compound influenced LPS-induced activation at 10 µM. Since only CBD had measurable effects on moDCs, in our subsequent experiments we tested the effect only of that pCB. On moDCs differentiated in the presence of CBD subsequent activation by LPS induced a markedly different, much more tolerogenic response. CBD-treated moDCs also produced significantly more interleukin (IL)-6, TNFα and, importantly, IL-10 in response to LPS, which shows a shift toward anti-inflammatory signaling, as well as a more robust secretory response in general. To rule out the possibility that these effects of CBD are specific to TLR4 signaling, we determined the effect of CBD on TLR7/8-induced maturation as well, and saw similar, although less marked responses. CBD-treated moDCs were also less efficient at activating naïve T cells after LPS stimulation, further supporting the tolerogenic effect of this phytocannabinoid on moDCs. Reactome pathway analysis showed an inflammatory response to LPS in moDCs, and to a lesser extent to CBD as well. In contrast CBD-treated moDCs responded to LPS with a shift towards a more tolerogenic phenotype, as IL-10 signaling was the most prominently induced pathway in this group. Discussion: Our results show that CBD achieves an anti-inflammatory effect on adaptive immune responses only in the presence of an activating stimuli on moDCs by reprogramming cells during long-term treatment, and not through acute, short-term effects.

Brief literature review and comprehensive bioinformatics analytics unravel the potential mechanism of curcumin in the treatment of periodontitis.

OBJECTIVE: Periodontitis is a chronic oral disease prevalent worldwide, and natural products are recommended as adjunctive therapy due to their minor side effects. Curcumin, a widely used ancient compound, has been reported to possess therapeutic effects in periodontitis. However, the exact mechanism underlying its activity remains unclear. In this context, the present study aimed to conduct computational simulations to uncover the potential mechanism of action of Curcumin in the treatment of periodontitis. MATERIALS AND METHODS: Single-cell analysis was conducted using a dataset (i.e., GSE164241) curated from the Gene Expression Omnibus (GEO) database through an R package "Seurat package." Bulk RNA sequencing data were curated from GSE10334 and GSE16134 and processed by R package "Limma." Then, the marker genes in the single-cell transcriptome and differentially expressed genes (DEGs) in the bulk transcriptome were integrated. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses were also carried out to reveal their functionalities. Key targets were mined from their protein-protein interaction (PPI) network topologically. Afterward, molecular docking was performed. The top-ranked pose was subjected to molecular dynamics simulations to investigate the stability of the docking result. RESULTS: FOS, CXCL1, CXCL8, and IL1B, were filtered after a series of selected processes. The results of molecular modeling suggested that except for IL1B, the Vena Scores of the rest exceeded -5 kcal/mol. Furthermore, the molecular dynamic simulation indicated that the binding of the CXCL8-Curcumin complex was stable over the entire 100 ns simulation. CONCLUSION: The present study unlocked the binding modes of CXCL1, FOS, and CXCL8 with the Curcumin molecule, which were relatively stable, especially for CXCL8, hindering its promising potential to serve as the critical targets of Curcumin in periodontitis treatment.

TRPV4 Activation Increases the Expression of CD207 (Langerin) of Monocyte-Derived Langerhans Cells without Affecting their Maturation.

Langerhans cells (LCs) are the sole professional antigen-presenting cell normally found in the human epidermal compartment. Research into their physiological role is hindered by the fact that they are invariably activated during isolation from the skin. To overcome this challenge, we turned to a monocyte-derived LC (moLC) model, which we characterized with RNA sequencing, and compared the transcriptome of moLCs with that of donor-matched immature dendritic cells. We found that moLCs express markers characteristic of LC2 cells as well as TRPV4. TRPV4 is especially important in the skin because it has been linked to the conservation of the skin barrier, immunological responses, as well as acute and chronic itch, but we know little about its function on LCs. Our results show that TRPV4 activation increased the expression of Langerin and led to increased intracellular calcium concentration in moLCs. Regarding the functionality of moLCs, we found that TRPV4 agonism had a mitigating effect on their inflammatory responses because it decreased their cytokine production and T-cell activating capability. Because TRPV4 has emerged as a potential therapeutic target in dermatological conditions, it is important to highlight LCs as, to our knowledge, a previously unreported target of these therapies.

Anandamide Concentration-Dependently Modulates Toll-Like Receptor 3 Agonism or UVB-Induced Inflammatory Response of Human Corneal Epithelial Cells.

Photodamage-induced and viral keratitis could benefit from treatment with novel nonsteroid anti-inflammatory agents. Therefore, we determined whether human corneal epithelial cells (HCECs) express members of the endocannabinoid system (ECS), and examined how the endocannabinoid anandamide (AEA, N-arachidonoyl ethanolamine) influences the Toll-like receptor 3 (TLR3) agonism- or UVB irradiation-induced inflammatory response of these cells. Other than confirming the presence of cannabinoid receptors, we show that endocannabinoid synthesizing and catabolizing enzymes are also expressed in HCECs in vitro, as well as in the epithelial layer of the human cornea in situ, proving that they are one possible source of endocannabinoids. p(I:C) and UVB irradiation was effective in promoting the transcription and secretion of inflammatory cytokines. Surprisingly, when applied alone in 100 nM and 10 µM, AEA also resulted in increased pro-inflammatory cytokine production. Importantly, AEA further increased levels of these cytokines in the UVB model, whereas its lower concentration partially prevented the transcriptional effect of p(I:C), while not decreasing the p(I:C)-induced cytokine release. HCECs express the enzymatic machinery required to produce endocannabinoids both in vitro and in situ. Moreover, our data show that, despite earlier reports about the anti-inflammatory potential of AEA in murine cornea, its effects on the immune phenotype of human corneal epithelium may be more complex and context dependent.

Autologous apoptotic neutrophils inhibit inflammatory cytokine secretion by human dendritic cells, but enhance Th1 responses.

Neutrophils represent the most abundant cell type in peripheral blood and exhibit a remarkably brief (6-8 h) half-life in circulation. The fundamental role of these professional phagocytes has been established in acute inflammation, based on their potential to both initiate and receive inflammatory signals. Furthermore, neutrophils also take part in maintaining chronic inflammatory processes, such as in various autoimmune diseases. Here, we demonstrate that human autologous apoptotic neutrophils are readily engulfed by immature monocyte-derived dendritic cells (moDCs) with similar efficiency as allogeneic apoptotic neutrophils [Majai G et al. (2010) J Leukoc Biol 88, 981-991]. Interestingly, in contrast to the allogeneic system, exposure of moDCs to autologous apoptotic neutrophils inhibits LPS + IFN-γ-induced production of inflammatory cytokines in a phagocytosis-independent manner. Autologous apoptotic neutrophil-primed DCs are able to modulate T-cell responses by inducing the generation of IFN-γ-secreting cells while hampering that of IL-17A-producing cells. Our observations indicate that capture of autologous apoptotic neutrophils by immature DCs may impede further neutrophil-mediated phagocytosis and tissue damage, and allow increased clearance of dying cells by macrophages.

Synthesis and Cytotoxic Activity of New Vindoline Derivatives Coupled to Natural and Synthetic Pharmacophores.

New Vinca alkaloid derivatives were synthesized to improve the biological activity of the natural alkaloid vindoline. To this end, experiments were performed to link vindoline with various structural units, such as amino acids, a 1,2,3-triazole derivative, morpholine, piperazine and N-methylpiperazine. The structure of the new compounds was characterized by NMR spectroscopy and mass spectrometry (MS). Several compounds exhibited in vitro antiproliferative activity against human gynecological cancer cell lines with IC50 values in the low micromolar concentration range.

RIG-I Resists Hypoxia-Induced Immunosuppression and Dedifferentiation.

A hypoxic tumor microenvironment is linked to poor prognosis. It promotes tumor cell dedifferentiation and metastasis and desensitizes tumor cells to type-I IFN, chemotherapy, and irradiation. The cytoplasmic immunoreceptor retinoic acid-inducible gene-I (RIG-I) is ubiquitously expressed in tumor cells and upon activation by 5'-triphosphate RNA (3pRNA) drives the induction of type I IFN and immunogenic cell death. Here, we analyzed the impact of hypoxia on the expression of RIG-I in various human and murine tumor and nonmalignant cell types and further investigated its function in hypoxic murine melanoma. 3pRNA-inducible RIG-I-expression was reduced in hypoxic melanoma cells compared with normoxic controls, a phenomenon that depended on the hypoxia-associated transcription factor HIF1α. Still, RIG-I functionality was conserved in hypoxic melanoma cells, whereas responsiveness to recombinant type-I IFN was abolished, due to hypoxia-induced loss of type I IFN receptor expression. Likewise, RIG-I activation in hypoxic melanoma cells, but not exposure to recombinant IFNα, provoked melanocyte antigen-specific CD8+ T-cell and NK-cell attack. Scavenging of hypoxia-induced reactive oxygen species by vitamin C restored the inducible expression of RIG-I under hypoxia in vitro, boosted in vitro anti-melanoma NK- and CD8+ T-cell attack, and augmented 3pRNA antitumor efficacy in vivo These results demonstrate that RIG-I remains operational under hypoxia and that RIG-I function is largely insensitive to lower cell surface expression of the IFNα receptor. RIG-I function could be fortified under hypoxia by the combined use of 3pRNA with antioxidants. Cancer Immunol Res; 5(6); 455-67. ©2017 AACR.

[Chemotherapeutic treatment of metastatic ovarian cancer for 8 years. Case report]. / Metasztatikus ovariumcarcinoma kemoterápiás kezelése nyolc éven át.

The authors present the history of a 48-year-old woman, who developed pleural effusion, abdominal pain and ascites due to an advanced ovarian cancer. She underwent hysterectomy and bilateral adnexectomy in 2006, and histology revealed FIGO IIIB papillary adenocarcinoma. After surgery the patient recieved the standard, 6 cycle taxol-carboplatin therapy. Taxol-carboplatin therapy was reinitiated because of retroperitoneal lymph node metastases in 2008, but soon the therapy had to be changed because of progression. Thereafter the patient recieved 6 different types of chemo- and biological therapy including the off-label FOLFOX-4 treatment at seventh line. Significant regression in response to FOLFOX-4 therapy was confirmed with a progression free survival of about 9 months. The general condition of the patient was satisfying during the whole chemotherapy, and the side effects were tolerable. The overall survival was 98 months. This case history is a good example for the success of individualized, long term chemotherapy even if ovarian tumor diagnosed at advanced stage as it happened in this case. Orv. Hetil., 2016, 157(44), 1769-1773.