Prevention Of Autoimmune Diseases Research Articles

Promising Role of Alkaloids in the Prevention and Treatment of Thyroid Cancer and Autoimmune Thyroid Disease: A Comprehensive Review of the Current Evidence.

Thyroid cancer (TC) and thyroid autoimmune disorders (AITD) are among the most common diseases in the general population, with higher incidence in women. Chronic inflammation and autoimmunity play a pivotal role in carcinogenesis. Some studies, indeed, have pointed out the presence of AITD as a risk factor for TC, although this issue remains controversial. Prevention of autoimmune disease and cancer is the ultimate goal for clinicians and scientists, but it is not always feasible. Thus, new treatments, that overcome the current barriers to prevention and treatment of TC and AITD are needed. Alkaloids are secondary plant metabolites endowed with several biological activities including anticancer and immunomodulatory properties. In this perspective, alkaloids may represent a promising source of prophylactic and therapeutic agents for TC and AITD. This review encompasses the current published literature on alkaloids effects on TC and AITD, with a specific focus on the pathways involved in TC and AITD development and progression.

Immune tolerance and the prevention of autoimmune diseases essentially depend on thymic tissue homeostasis.

The intricate balance of immune reactions towards invading pathogens and immune tolerance towards self is pivotal in preventing autoimmune diseases, with the thymus playing a central role in establishing and maintaining this equilibrium. The induction of central immune tolerance in the thymus involves the elimination of self-reactive T cells, a mechanism essential for averting autoimmunity. Disruption of the thymic T cell selection mechanisms can lead to the development of autoimmune diseases. In the dynamic microenvironment of the thymus, T cell migration and interactions with thymic stromal cells are critical for the selection processes that ensure self-tolerance. Thymic epithelial cells are particularly significant in this context, presenting self-antigens and inducing the negative selection of autoreactive T cells. Further, the synergistic roles of thymic fibroblasts, B cells, and dendritic cells in antigen presentation, selection and the development of regulatory T cells are pivotal in maintaining immune responses tightly regulated. This review article collates these insights, offering a comprehensive examination of the multifaceted role of thymic tissue homeostasis in the establishment of immune tolerance and its implications in the prevention of autoimmune diseases. Additionally, the developmental pathways of the thymus are explored, highlighting how genetic aberrations can disrupt thymic architecture and function, leading to autoimmune conditions. The impact of infections on immune tolerance is another critical area, with pathogens potentially triggering autoimmunity by altering thymic homeostasis. Overall, this review underscores the integral role of thymic tissue homeostasis in the prevention of autoimmune diseases, discussing insights into potential therapeutic strategies and examining putative avenues for future research on developing thymic-based therapies in treating and preventing autoimmune conditions.

Causal effects of endometriosis on SLE, RA and SS risk: evidence from meta-analysis and Mendelian randomization

BackgroundEndometriosis is an underdiagnosed disorder that affects an estimated 6-10% of women of reproductive age. Endometriosis has been reported in epidemiological studies to be associated with autoimmune diseases. However, the relationship remains controversial.MethodsA meta-analysis of observational studies was undertaken to evaluate the risk of autoimmune diseases in patients with endometriosis. The relevant studies were retrieved via the databases Medline, Embase and Web of Science until July 20, 2023. Mendelian randomization (MR) was subsequently utilized to scrutinize the causal influence of genetic predisposition toward endometriosis on three autoimmune diseases.ResultsThe meta-analysis findings revealed a relationship between endometriosis and the onset of SLE (cohort studies: RR = 1.77, 95% confidence interval (CI): 1.47–2.13, I2 = 0%; Case-control and cross-sectional studies: OR = 5.23, 95% CI: 0.74–36.98, I2 = 98%), RA (cohort studies: RR = 2.18, 95% CI: 1.85–2.55, I2 = 92%; Case-control and cross-sectional studies: OR = 1.40, 95% CI: 1.19–1.64, I2 = 0%) and SS (cohort studies: RR = 1.49, 95% CI: 1.34–1.66, I2 = 0%). Similarly, in our MR study, the results of the inverse-variance-weighted (IVW) model suggested that genetic predisposition to endometriosis was causally associated with an increased risk for SLE (OR = 1.915, 95% CI: 1.204–3.045, p = 0.006) and RA (OR = 1.005, 95% CI: 1.001–1.009, p = 0.014).ConclusionsBoth our meta-analysis and MR study indicate that endometriosis increases the risk of autoimmune diseases. These findings not only broaden our understanding of the genetic mechanisms underlying the comorbidity of endometriosis and autoimmune diseases, but also offer a new strategy for autoimmune disease prevention.

Vitamin D and Marine n-3 Fatty Acids for Autoimmune Disease Prevention: Outcomes Two Years After Completion of a Double-Blind, Placebo-Controlled Trial.

In the 5.3-year randomized, 2 × 2 factorial, double-blind, placebo-controlled Vitamin D and Omega-3 Trial (VITAL), vitamin D supplementation reduced autoimmune disease (AD) incidence (hazard ratio [HR] 0.78, 95% confidence interval [CI] 0.61-0.99). Omega-3 (n-3) fatty acid supplementation showed a statistically nonsignificant reduction (HR 0.85, 95% CI 0.67-1.08). We aimed to confirm further AD cases arising during and after randomization and assess sustained effects with two years of postintervention observation. Of the 12,786 men aged ≥50 and 13,085 women aged ≥55 initially randomized, we observed surviving and willing participants for two more years. We continued to confirm annual participant-reported new AD by medical record review. Cox models calculated HRs for all confirmed incident AD, (and secondary endpoints, including probable cases, and individual ADs), during the observational and randomized periods. A total of 21,592 participants (83.5%) were observed for two more years; 514 participants developed incident confirmed AD (236 since prior report), of whom 255 had been randomized to vitamin D versus 259 to vitamin D placebo (HR 0.98 [95% CI 0.83-1.17] at 7 years). AD was confirmed in 234 participants initially randomized to n-3 fatty acids versus 280 randomized to its placebo (HR 0.83 [95% CI 0.70-0.99] at 7 years). Of newly confirmed cases, 65 had onset during randomization; their inclusion changed randomized results as follows: HR 0.85 (95% CI 0.70-1.04) for vitamin D and HR 0.87 (95% CI 0.71-1.06) for n-3 fatty acids. Two years after trial termination, the protective effects of 2000 IU/day of vitamin D dissipated, but 1,000 mg/day of n-3 fatty acids had a sustained effect in reducing AD incidence.

The type 1 diabetes susceptibility locus Idd5 favours robust neonatal development of highly autoreactive regulatory T cells in the NOD mouse.

Regulatory T lymphocytes expressing the transcription factor Foxp3 (Tregs) play an important role in the prevention of autoimmune diseases and other immunopathologies. Aberrations in Treg-mediated immunosuppression are therefore thought to be involved in the development of autoimmune pathologies, but few have been documented. Recent reports indicated a central role for Tregs developing during the neonatal period in the prevention of autoimmune pathology. We therefore investigated the development of Tregs in neonatal NOD mice, an important animal model for autoimmune type 1 diabetes. Surprisingly, we found that, as compared with seven other commonly studied inbred mouse strains, in neonatal NOD mice, exceptionally large proportions of developing Tregs express high levels of GITR and PD-1. The latter phenotype was previously associated with high Treg autoreactivity in C57BL/6 mice, which we here confirm for NOD animals. The proportions of newly developing GITRhighPD-1+ Tregs rapidly drop during the first week of age. A genome-wide genetic screen indicated the involvement of several diabetes susceptibility loci in this trait. Analysis of a congenic mouse strain confirmed that Idd5 contributes to the genetic control of GITRhighPD-1+ Treg development in neonates. Our data thus demonstrate an intriguing and paradoxical correlation between an idiosyncrasy in Treg development in NOD mice and their susceptibility to type 1 diabetes.

T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain as a promising immune checkpoint target for the treatment of SLE.

Immune checkpoints (ICs) play a pivotal role in orchestrating immune regulation, crucial for the maintenance of immune tolerance and prevention of autoimmune diseases. One noteworthy example among these immune regulators is T cell immunoglobulin (Ig) and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT). The TIGIT pathway's inhibition or the absence of TIGIT has been linked to the hyperactivation and excessive proliferation of T cells, rendering individuals more susceptible to autoimmune diseases and exacerbating inflammatory responses. Conversely, the activation of TIGIT has exhibited promising outcomes in ameliorating autoimmune disorders, as observed in murine models of systemic lupus erythematosus (SLE). Consequently, a judicious exploration of the co-inhibitory axis appears warranted for the effective management of pathogenic immune responses in SLE. In light of compelling evidence, this review undertakes a comprehensive examination of TIGIT's characteristics within the context of autoimmunity, offering insights into its potential as a therapeutic target for SLE.

Beyond FOXP3: a 20-year journey unravelling human regulatory T-cell heterogeneity.

The initial idea of a distinct group of T-cells responsible for suppressing immune responses was first postulated half a century ago. However, it is only in the last three decades that we have identified what we now term regulatory T-cells (Tregs), and subsequently elucidated and crystallized our understanding of them. Human Tregs have emerged as essential to immune tolerance and the prevention of autoimmune diseases and are typically contemporaneously characterized by their CD3+CD4+CD25high CD127lowFOXP3+ phenotype. It is important to note that FOXP3+ Tregs exhibit substantial diversity in their origin, phenotypic characteristics, and function. Identifying reliable markers is crucial to the accurate identification, quantification, and assessment of Tregs in health and disease, as well as the enrichment and expansion of viable cells for adoptive cell therapy. In our comprehensive review, we address the contributions of various markers identified in the last two decades since the master transcriptional factor FOXP3 was identified in establishing and enriching purity, lineage stability, tissue homing and suppressive proficiency in CD4+ Tregs. Additionally, our review delves into recent breakthroughs in innovative Treg-based therapies, underscoring the significance of distinct markers in their therapeutic utilization. Understanding Treg subsets holds the key to effectively harnessing human Tregs for immunotherapeutic approaches.

Research progress on the relationship between COVID-19 and autoimmune diseases

Different autoantibodies can be detected in patients with coronavirus disease 2019 (COVID-19). It is reported that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection could induce autoimmune diseases (AID), including children's multisystem inflammatory syndrome (MIS-C), Guillain Barre syndrome (GBS), Autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP) and thyroid autoimmune diseases. This article mainly reviews the similarities between COVID-19 and AID, the possibility of COVID-19 inducing AID, the risk of AID patients infected or vaccinated against COVID-19. The purpose is to provide strategies for the prevention, management and treatment of AID during the epidemic.

Selective targeting of auto reactive B cells using bispecific molecules

Abstract Type 1 diabetes occurs when autoreactive T cells attack insulin-producing cells in pancreatic islets. B cells promote disease by acting as essential antigen presenting cells. Targeted immune therapy for treatment and prevention of autoimmune diseases is preferable to drugs that cause global immunosuppression. We therefore investigated the efficacy of three constructs designed to specifically target and neutralize anti-insulin B cells. Construct one has a 4-arm PEG backbone with insulin attached to 2 of the arms (insulin-PEG). Construct two has insulin attached to 2 of the PEG arms and a trisaccharide molecule that acts as a ligand for inhibitory receptor CD22 on the remaining 2 PEG arms (insulin-PEG-CD22L). Construct three consists of insulin directly conjugated to CD22L (insulin-CD22L). In vitro experiments using transgenic anti-insulin B cells demonstrate that insulin-PEG unexpectedly promotes excessive proliferation and upregulation of CD86 in anti-CD40 treated anti-insulin B cells. Addition of CD22L (insulin-PEG-CD22L) restores anti-insulin B cell responses to baseline but has no overall benefit. Conversely, insulin-CD22L blunts the effects of anti-CD40 stimulation, reducing proliferation by 15% and IgM surface expression by 50% . CD22L alone has no effect on stimulated anti-insulin B cells. Preliminary in vivo data using 2-photon imaging shows that insulin-CD22L binds anti-insulin B cells in spleen, pancreatic lymph nodes and pancreatic islets within 30 minutes of injection. Thus, this novel insulin-CD22L construct directs the dampening effect of CD22 specifically to anti-insulin B cells that promote T1D, making it a promising therapeutic intervention that may also be useful when paired with anti-T cell treatments. P20GM1133117 T32GM008545 5T32AI7163-43

Preventing rheumatoid arthritis: Lessons from that of type 1 diabetes

Preventing rheumatoid arthritis: Lessons from that of type 1 diabetes

Correction of endocrine complications of oncoimmunotherapy

Over the years, immunotherapy with immune checkpoint inhibitors (ICI) has become an effective treatment for malignant neoplasms. However, checkpoints play a crucial role in immunological tolerance and prevention of autoimmune diseases. Interfering with this mechanism can cause immune-related adverse events (IRAEs) that affect multiple organs in the body. Endocrinopathies are among the most common IRAES associated with ICI therapy. Given the unique nature of adverse events caused by the use of ICI drugs, a multidisciplinary team approach is required to effectively manage patients, minimize complications associated with drug toxicity, and fully realize the therapeutic potential of this treatment method. Taking into account the difficulty of detecting nonspecific symptoms, the importance of follow-up and timely intervention in case of toxicity detection, regular clinical and laboratory monitoring is necessary, as well as informing patients and doctors about the variants of endocrine adverse events and their treatment. While non-endocrine IRAES often require discontinuation of immunotherapy and are usually resolved by immunosuppressive therapy with high doses of glucocorticoids, endocrine IRAES usually do not need discontinuation of ICI treatment and rarely require immunosuppressive therapy, but seldomly regress and therefore demand a long-term treatment.

Macrophage: Key player in the pathogenesis of autoimmune diseases.

The macrophage is an essential part of the innate immune system and also serves as the bridge between innate immunity and adaptive immune response. As the initiator and executor of the adaptive immune response, macrophage plays an important role in various physiological processes such as immune tolerance, fibrosis, inflammatory response, angiogenesis and phagocytosis of apoptotic cells. Consequently, macrophage dysfunction is a vital cause of the occurrence and development of autoimmune diseases. In this review, we mainly discuss the functions of macrophages in autoimmune diseases, especially in systemic lupus erythematosus (SLE), rheumatic arthritis (RA), systemic sclerosis (SSc) and type 1 diabetes (T1D), providing references for the treatment and prevention of autoimmune diseases.

The role of metabolism on regulatory T cell development and its impact in tumor and transplantation immunity.

Regulatory CD4+ T (Treg) cells play a key role in the induction of immune tolerance and in the prevention of autoimmune diseases. Treg cells are defined by the expression of transcription factor FOXP3, which ensures proliferation and induction of the suppressor activity of this cell population. In a tumor microenvironment, after transplantation or during autoimmune diseases, Treg cells can respond to various signals from their environment and this property ensures their suppressor function. Recent studies showed that a metabolic signaling pathway of Treg cells are essential in the control of Treg cell proliferation processes. This review presents the latest research highlights on how the influence of extracellular factors (e.g. nutrients, vitamins and metabolites) as well as intracellular metabolic signaling pathways regulate tissue specificity of Treg cells and heterogeneity of this cell population. Understanding the metabolic regulation of Treg cells should provide new insights into immune homeostasis and disorders along with important therapeutic implications for autoimmune diseases, cancer and other immune-system-mediated disorders.

Antibody-Mediated Targeting of a Hybrid Insulin Peptide Toward Neonatal Thymic Langerin-Positive Cells Enhances T-Cell Central Tolerance and Delays Autoimmune Diabetes.

Thymic presentation of self-antigens is critical for establishing a functional yet self-tolerant T-cell population. Hybrid peptides formed through transpeptidation within pancreatic β-cell lysosomes have been proposed as a new class of autoantigens in type 1 diabetes (T1D). While the production of hybrid peptides in the thymus has not been explored, due to the nature of their generation, it is thought to be highly unlikely. Therefore, hybrid peptide-reactive thymocytes may preferentially escape thymic selection and contribute significantly to T1D progression. Using an antibody-peptide conjugation system, we targeted the hybrid insulin peptide (HIP) 2.5HIP toward thymic resident Langerin-positive dendritic cells to enhance thymic presentation during the early neonatal period. Our results indicated that anti-Langerin-2.5HIP delivery can enhance T-cell central tolerance toward cognate thymocytes in NOD.BDC2.5 mice. Strikingly, a single dose treatment with anti-Langerin-2.5HIP during the neonatal period delayed diabetes onset in NOD mice, indicating the potential of antibody-mediated delivery of autoimmune neoantigens during early stages of life as a therapeutic option in the prevention of autoimmune diseases.

Regulatory T Cells from Patients with Rheumatoid Arthritis Are Characterized by Reduced Expression of Ikaros Zinc Finger Transcription Factors.

Regulatory T (Treg) cells play an important role in immune tolerance and contribute to the prevention of autoimmune diseases, including rheumatoid arthritis (RA). The differentiation, function and stability of Treg cells is controlled by members of the Ikaros zinc finger transcription factor family. In this study, we aimed to reveal how the expression of Ikaros transcription factors is affected by disease activity in RA. Therefore, we analyzed the ex vivo expression of Ikaros, Helios, Aiolos and Eos in Treg cells, Th17 cells and Th1 cells from RA patients by flow cytometry. We found significantly reduced expression of Helios, Aiolos and Eos in Treg cells from RA patients as compared to healthy controls. Moreover, Helios and Aiolos levels correlated with disease activity, as assessed by DAS28-CRP. In addition, Ikaros, Helios and Aiolos were significantly downregulated in Th1 cells from RA patients, while no difference between healthy individuals and RA was observed in Th17 cells. In summary, Helios and Aiolos expression in Treg cells correlates with disease activity and the expression levels of Ikaros transcription factors are diminished in Treg cells from RA patients. This observation could explain the reduced stability of Treg cells in RA.

Preclinical Autoimmune Disease: a Comparison of Rheumatoid Arthritis, Systemic Lupus Erythematosus, Multiple Sclerosis and Type 1 Diabetes.

The preclinical phase of autoimmune disorders is characterized by an initial asymptomatic phase of varying length followed by nonspecific signs and symptoms. A variety of autoimmune and inflammatory manifestations can be present and tend to increase in the last months to years before a clinical diagnosis can be made. The phenotype of an autoimmune disease depends on the involved organs, the underlying genetic susceptibility and pathophysiological processes. There are different as well as shared genetic or environmental risk factors and pathophysiological mechanisms between separate diseases. To shed more light on this, in this narrative review we compare the preclinical disease course of four important autoimmune diseases with distinct phenotypes: rheumatoid arthritis (RA), Systemic Lupus Erythematosus (SLE), multiple sclerosis (MS) and type 1 diabetes (T1D). In general, we observed some notable similarities such as a North-South gradient of decreasing prevalence, a female preponderance (except for T1D), major genetic risk factors at the HLA level, partly overlapping cytokine profiles and lifestyle risk factors such as obesity, smoking and stress. The latter risk factors are known to produce a state of chronic systemic low grade inflammation. A central characteristic of all four diseases is an on average lengthy prodromal phase with no or minor symptoms which can last many years, suggesting a gradually evolving interaction between the genetic profile and the environment. Part of the abnormalities may be present in unaffected family members, and autoimmune diseases can also cluster in families. In conclusion, a promising strategy for prevention of autoimmune diseases might be to address adverse life style factors by public health measures at the population level.

Impaired activation of STAT5 upon IL-2 stimulation in Tregs and elevated sIL-2R in Sjögren’s syndrome

BackgroundInterleukin-2 (IL-2) and the high-affinity IL-2 receptor (IL-2R) are essential for the survival of regulatory T cells (Tregs) which are the main players in immune tolerance and prevention of autoimmune diseases. Sjögren’s syndrome (SS) is a chronic autoimmune disease predominantly affecting women and is characterised by sicca symptoms including oral and ocular dryness. The aim of this study was to investigate an association between IL-2R and Treg function in patients with SS of different severity defined by the salivary flow rate.MethodsIn a cross-sectional study, we determined plasma soluble IL-2R (sIL-2R) levels in women with SS (n=97) and healthy females (n=50) using ELISA. A subset of those (n=51) was screened for Treg function measured by the STAT5 signalling response to IL-2 using phospho-flow cytometry.ResultsWe found that elevated plasma levels of sIL-2R were positively associated with the severity of SS reflected by a pathologically low salivary flow. Phospho-flow analysis revealed that patients with SS have a significantly lower frequency of pSTAT5+ Tregs upon IL-2 stimulation compared with healthy individuals, while the frequency of Tregs and pSTAT5 in conventional T cells remained unchanged. In addition, we observed more pSTAT5+ Tregs at baseline in patients with SS, which is significantly associated with seropositivity and elevated sIL-2R.ConclusionsOur data indicates that Tregs have a weakened immunosuppressive function in patients with SS due to impaired IL-2/IL-2R signalling capacity. This could mediate lymphocytic infiltration into salivary glands inducing sicca symptoms. We believe that sIL-2R could act as a useful indicator for SS and disease severity.

Low vitamin D levels do not predict risk of autoimmune disease following alemtuzumab treatment for multiple sclerosis

Alemtuzumab is a highly effective treatment for multiple sclerosis (MS) and the treatment strategy of two cycles 12 months apart has a lot of appeal to patients. Widespread use of alemtuzumab has been tempered by treatment emergent autoimmunity which is seen in approximately one-third of patients in the 5 years after treatment. It has been postulated that relative vitamin D deficiency may be a causative factor in this setting. We have conducted a retrospective case-control study looking at the association of vitamin D and other potentially relevant clinical factors on the likelihood of treatment emergent autoimmune disease following alemtuzumab. Occurrence of autoimmunity was monitored for clinically and through the Bloodwatch® monitoring program. Clinical data and vitamin D levels obtained as part of routine clinical practice were recorded. Vitamin D levels were seasonally adjusted. Only cases with complete data were included. Univariable and multivariable Cox proportional hazards analyses were performed. There were 113 patients treated with alemtuzumab for whom there was complete data. Median follow up was 4.4 years. Risk of autoimmune disease was not associated with lower vitamin D levels. Risk of autoimmune disease was associated with female sex (HR 3.5) and with higher EDSS score at treatment. The association with EDSS was lost when analysis was restricted to those with 4 or more years of follow up. These data do not support a role for vitamin D supplementation in the prevention of autoimmune disease following alemtuzumab. Males have a lower risk of autoimmunity following alemtuzumab.

HLA Allele-Specific Quantitative Profiling of Type 1 Diabetic B Lymphocyte Immunopeptidome.

Peptide ligands presented by human leukocyte antigen (HLA) molecules on the cell surface represent the immunopeptidome that could be utilized for identification of antigenic peptides for immunotherapy and prevention of autoimmune diseases. Although T-cells are well-known key players in the destruction of pancreatic beta-cells in type 1 diabetes (T1D), increasing evidence points toward a role for B-cells in disease pathogenesis. However, as antigen presenting cells, little is known about the comprehensive immunopeptidome of B cells and their changes in the context of T1D. We performed HLA allele-specific quantitative immunopeptidomics using B lymphocytes derived from T1D patients and healthy controls. Hundreds of HLA-I and HLA-II immunopeptides were identified as differentially regulated in T1D per HLA allele for B cells sharing identical HLA alleles. The results were further validated using additional T1D and healthy B cells with partially overlapped HLA alleles. Differentially expressed immunopeptides were confirmed with targeted proteomics and for reactivity using known T-cell assays in the immune epitope database. Considering samples with identical HLA alleles are difficult to obtain for T1D and other similar HLA-restricted diseases, our work represents a viable approach to better understand HLA allele-specific antigen presentation and may facilitate identification of immunopeptides for therapeutic applications in autoimmune diseases. Data are available via ProteomeXchange with identifier PXD026184.

Imaging dendritic cell functions.

Dendritic cells (DCs) are crucial for the appropriate initiation of adaptive immune responses. During inflammation, DCs capture antigens, mature, and migrate to lymphoid tissues to present foreign material to naïve T cells. These cells get activated and differentiate either into pathogen-specific cytotoxic CD8+ T cells that destroy infected cells or into CD4+ T helper cells that, among other effector functions, orchestrate antibody production by B cells. DC-mediated antigen presentation is equally important in non-inflammatory conditions. Here, DCs mediate induction of tolerance by presenting self-antigens or harmless environmental antigens and induce differentiation of regulatory T cells or inactivation of self-reactive immune cells. Detailed insights into the biology of DCs are, therefore, crucial for the development of novel vaccines as well as the prevention of autoimmune diseases. As in many other life science areas, our understanding of DC biology would be extremely restricted without bioimaging, a compilation of methods that visualize biological processes. Spatiotemporal tracking of DCs relies on various imaging tools, which not only enable insights into their positioning and migration within tissues or entire organs but also allow visualization of subcellular and molecular processes. This review aims to provide an overview of the imaging toolbox and to provide examples of diverse imaging techniques used to obtain fundamental insights into DC biology.