Project description:Vitamin D₃ is a key micronutrient known to support innate immunity and modulate adaptive responses, with in vitro studies suggesting the involvement of epigenetic mechanisms. However, in vivo evidence remains limited. In this study, we investigated genome-wide epigenomic responses to vitamin D₃ supplementation in a cohort of 38 individuals from a Polish population. Peripheral blood mononuclear cells (PBMCs) were collected at baseline (day 0) and 24 hours after supplementation (day 1). ATAC-seq analyses revealed widespread vitamin D₃-induced changes in chromatin accessibility.
Project description:Vitamin D3 is a key micronutrient known to support innate immunity and modulate adaptive responses, with in vitro studies suggesting involvement of epigenetic mechanisms. However, in vivo evidence for such regulation remains limited. In this proof-of-principle study, we investigated genome-wide epigenomic and transcriptomic responses to vitamin D₃ in a high responder (n=1) from the VitDHiD intervention trial. The participant received monthly oral boluses of 80,000 IU vitamin D3 over three months. Peripheral blood mononuclear cells were collected at baseline (day 0) and at 24 and 48 hours post-supplementation (days 1 and 2) for ATAC-seq and RNA-seq profiling. ATAC-seq revealed over 3,500 regions with increased chromatin accessibility, mainly at gene promoters, indicating a strong epigenomic response. Motif enrichment analysis identified immune-regulatory transcription factors, but not VDR (vitamin D receptor) motifs, suggesting indirect or cooperative regulation. RNA-seq identified 380 vitamin D target genes with time-dependent expression changes, including DUSP6 and FOS. Functional enrichment highlighted pathways related to innate immunity and interferon signaling. Integrative analysis linked 306 differentially expressed genes to nearby vitamin D-sensitive chromatin regions, including both promoters and enhancers. Many of these overlapped with VDR binding sites and promoters of neighboring non-target genes, indicating potential long-range regulatory interactions. Redundancies in regulatory elements were observed among closely located genes sharing enhancers and promoters. These findings provide in vivo evidence that vitamin D3 modulates chromatin accessibility and gene expression, supporting its role as an epigenetic regulator of immune function and highlighting its potential in personalized nutrition and immune health.
Project description:Vitamin D₃ is a key micronutrient known to support innate immunity and modulate adaptive responses, with in vitro studies suggesting involvement of epigenetic mechanisms. However, in vivo evidence for such regulation remains limited. In this proof-of-principle study, we investigated genome-wide epigenomic and transcriptomic responses to vitamin D₃ in a high responder (n=1) from the VitDHiD intervention trial. The participant received monthly oral boluses of 80,000 IU vitamin D₃ over three months. Peripheral blood mononuclear cells were collected at baseline (day 0) and at 24 and 48 hours post-supplementation (days 1 and 2) for ATAC-seq and RNA-seq profiling. ATAC-seq revealed over 3,500 regions with increased chromatin accessibility, mainly at gene promoters, indicating a strong epigenomic response. Motif enrichment analysis identified immune-regulatory transcription factors, but not VDR (vitamin D receptor) motifs, suggesting indirect or cooperative regulation. RNA-seq identified 380 vitamin D target genes with time-dependent expression changes, including DUSP6 and FOS. Functional enrichment highlighted pathways related to innate immunity and interferon signaling. Integrative analysis linked 306 differentially expressed genes to nearby vitamin D-sensitive chromatin regions, including both promoters and enhancers. Many of these overlapped with VDR binding sites and promoters of neighboring non-target genes, indicating potential long-range regulatory interactions. Redundancies in regulatory elements were observed among closely located genes sharing enhancers and promoters. These findings provide in vivo evidence that vitamin D₃ modulates chromatin accessibility and gene expression, supporting its role as an epigenetic regulator of immune function and highlighting its potential in personalized nutrition and immune health.
Project description:Oncogenic KRAS mutations are the most frequent mutations in human cancer, but most difficult to target. While sustained proliferation caused by oncogenic KRAS-downstream signalling is a main driver of carcinogenesis, there is increasing evidence that it also mediates autocrine effects and crosstalk with the tumour microenvironment (TME). Here, we discuss recent reports connecting KRAS mutations with tumour-promoting inflammation and immune modulation caused by KRAS that leads to immune escape in the TME. We discuss the preclinical work on KRAS-induced inflammation and immune modulation in the context of currently ongoing clinical trials targeting cancer entities that carry KRAS mutations and strategies to overcome the oncogene-induced effects on the immune system.
Project description:Viola tricolor is a medicinal plant with documented application as an anti-inflammatory herb. The standard of care for the treatment of inflammatory bowel disease is immunosuppressive therapeutics or biologics, which often have undesired effects. We explored V. tricolor herbal preparations that are rich in an emerging class of phytochemicals with drug-like properties, so-called cyclotides. As an alternative to existing inflammatory bowel disease medications, cyclotides have immunomodulatory properties, and their intrinsic stability allows for application in the gastrointestinal tract, for instance, via oral administration. We optimized the isolation procedure to improve the yield of cyclotides and compared the cellular effects of violet-derived organic solvent-extracts, aqueous preparations, and an isolated cyclotide from this plant on primary human T lymphocytes and macrophages, i.e., cells that are crucial for the initiation and progression of inflammatory bowel disease. The hot water herbal decoctions have a stronger immunosuppressive activity towards proliferation, interferon-γ, and interleukin-21 secretion of primary human T cells than a DCM/MeOH cyclotide-enriched extract, and the isolated cyclotide kalata S appears as one of the active components responsible for the observed effects. This effect was increased by a longer boiling duration. In contrast, the DCM/MeOH cyclotide-enriched extract was more effective in reducing the levels of cytokines interleukin-6, interleukin-12, interleukin-23, tumor necrosis factor-α, and C - X-C motif chemokine ligand 10, secreted by human monocyte-derived macrophages. Defined cyclotide preparations of V. tricolor have promising pharmacological effects in modulating immune cell responses at the cytokine levels. This is important towards understanding the role of cyclotide-containing herbal drug preparations for future applications in immune disorders, such as inflammatory bowel disease.
Project description:Beyond its well-documented role in reproduction, embryogenesis and maintenance of body tissues, vitamin A has attracted considerable attention due to its immunomodulatory effects on both the innate and the adaptive immune responses. In infectious diseases, vitamin A has been shown to have a host-protective effect in infections of bacterial, viral or protozoan origin. Nevertheless, its impact in fungal infections remains unknown. Meanwhile, the frequency of invasive mycoses keeps on growing, with Candida albicans being the major opportunistic fungal pathogen and associated with high mortality. In the present work, we explored the impact of all-trans retinoic acid (atRA), the most active metabolite of vitamin A, on the innate immune response against C. albicans in human monocytes. Our results show a strong immunomodulatory role for atRA, leading to a significant down-regulation of the fungi-induced expression and secretion of the pro-inflammatory cytokines TNFα, IL6 and IL12. Moreover, atRA significantly suppressed the expression of Dectin-1, a major fungal pattern recognition receptor, as well as the Dectin-1-dependent cytokine production. Both RAR-dependent and RAR-independent mechanisms seem to play a role in the atRA-mediated immunomodulation. Our findings open a new direction to elucidate the role of vitamin A on the immune function during fungal infections.
Project description:Intravenous immunoglobulin administered at replacement dosages modulates innate and adaptive immune cells in primary antibody deficiencies (PAD) in a different manner to what observed when high dosages are used or when their effect is analyzed by in vitro experimental conditions. The effects seem to be beneficial on innate cells in that dendritic cells maturate, pro-inflammatory monocytes decrease, and neutrophil function is preserved. The effects are less clear on adaptive immune cells. IVIg induced a transient increase of Treg and a long-term increase of CD4 cells. More complex and less understood is the interplay of IVIg with defective B cells of PAD patients. The paucity of data underlies the need of more studies on patients with PAD before drawing conclusions on the in vivo mechanisms of action of IVIg based on in vitro investigations.
Project description:IL-22 is a Th17/Th22 cytokine that is increased in asthma. However, recent animal studies showed controversial findings in the effects of IL-22 in allergic asthma. To determine the role of IL-22 in ovalbumin-induced allergic inflammation we generated inducible lung-specific IL-22 transgenic mice. Transgenic IL-22 expression and signaling activity in the lung were determined. Ovalbumin (OVA)-induced pulmonary inflammation, immune responses, and airway hyperresponsiveness (AHR) were examined and compared between IL-22 transgenic mice and wild type controls. Following doxycycline (Dox) induction, IL-22 protein was readily detected in the large (CC10 promoter) and small (SPC promoter) airway epithelial cells. IL-22 signaling was evidenced by phosphorylated STAT3. After OVA sensitization and challenge, compared to wild type littermates, IL-22 transgenic mice showed decreased eosinophils in the bronchoalveolar lavage (BAL), and in lung tissue, decreased mucus metaplasia in the airways, and reduced AHR. Among the cytokines and chemokines examined, IL-13 levels were reduced in the BAL fluid as well as in lymphocytes from local draining lymph nodes of IL-22 transgenic mice. No effect was seen on the levels of serum total or OVA-specific IgE or IgG. These findings indicate that IL-22 has immune modulatory effects on pulmonary inflammatory responses in allergen-induced asthma.
Project description:Atherosclerotic cardiovascular diseases (CVD) are among the leading causes of death in the world. Monocyte-derived macrophages are key players in the pathophysiology of atherosclerosis. Innate immune memory following exposure of monocytes to atherogenic compounds, such as oxidized low-density lipoproteins (oxLDL), termed trained immunity, can contribute to atherogenesis. The current study aimed to elucidate intracellular mechanisms of oxLDL-induced trained immunity. Using untargeted intracellular metabolomics in isolated human primary monocytes, we show that oxLDL-induced trained immunity results in alterations in the balance of intracellular steroid hormones in monocytes. This was reflected by a decrease in extracellular progesterone concentrations following LPS stimulation. To understand the potential effects of steroid hormones on trained immunity, monocytes were costimulated with oxLDL and the steroid hormones progesterone, hydrocortisone, dexamethasone, β-estradiol, and dihydrotestosterone. Progesterone showed a unique ability to attenuate the enhanced TNFα and IL-6 production following oxLDL-induced trained immunity. Single nucleotide polymorphisms in the nuclear glucocorticoid, progesterone, and mineralocorticoid receptor were shown to correlate with ex vivo oxLDL-induced trained immunity in 243 healthy volunteers. Pharmacologic inhibition experiments revealed that progesterone exerts the suppression of TNFα in trained immunity via the nuclear glucocorticoid and mineralocorticoid receptors. Our data show that progesterone has a unique ability to suppress oxLDL-induced trained immunity. We hypothesize that this effect might contribute to the lower incidence of CVD in premenopausal women.