Changes in circulating cell-free DNA and nucleosomes in patients with exacerbated psoriasis

Systematically Evaluating Cell-Free DNA Fragmentation Patterns for Cancer Diagnosis and Enhanced Cancer Detection via Integrating Multiple Fragmentation Patterns

Cell-free DNA (cfDNA) fragmentation patterns have immense potential for early cancer detection. However, the definition of fragmentation varies, ranging from the entire genome to specific genomic regions. These patterns have not been systematically compared, impeding broader research and practical implementation. Here, 1382 plasma cfDNA sequencing samples from 8 cancer types are collected. Considering that cfDNA within open chromatin regions is more susceptible to fragmentation, 10 fragmentation patterns within open chromatin regions as features and employed machine learning techniques to evaluate their performance are examined. All fragmentation patterns demonstrated discernible classification capabilities, with the end motif showing the highest diagnostic value for cross-validation. Combining cross and independent validation results revealed that fragmentation patterns that incorporated both fragment length and coverage information exhibited robust predictive capacities. Despite their diagnostic potential, the predictive power of these fragmentation patterns is unstable. To address this limitation, an ensemble classifier via integrating all fragmentation patterns is developed, which demonstrated notable improvements in cancer detection and tissue-of-origin determination. Further functional bioinformatics investigations on significant feature intervals in the model revealed its impressive ability to identify critical regulatory regions involved in cancer pathogenesis.

Elevation of circulating DNAs of disease-associated cytokines in serum cell-free DNA from patients with alopecia areata

Alopecia areata (AA) is an autoimmune disease characterized by damage to hair follicles and hair loss. Cell-free DNA (cfDNA) has recently received attention as a biomarker of various disorders including inflammatory skin diseases. In this study, we aimed to investigate the clinical significance of cfDNA and the circulating DNAs of disease-associated cytokines in AA patients. Serum samples were obtained from 63 patients with AA and 32 healthy controls (HC). Using droplet digital polymerase chain reaction, circulating C-X-C motif chemokine ligand (CXCL) 9, CXCL10, CXCL11, C-X-C motif chemokine receptor 3, interferon (IFN)-γ, interleukin (IL) -7, IL-15, and Janus kinase (JAK) 2 were detectable in both HC and AA patients. Among the detectable DNAs, copies of circulating CXCL9, CXCL11, IL-15, IFN-γ, and JAK2 were significantly higher in AA patients than in HC. These results suggest that increased circulating DNA levels may reflect damage to hair follicles in AA patients.

Biguanide chitosan microneedles with cell-free DNA scavenging ability for psoriasis therapy

High levels of cell-free DNA (cfDNA) induce psoriasis. Currently, the treatment of psoriasis has the disadvantages of penetration difficulty, suppression of normal immunity, and skin irritation. In this study, biguanide chitosan microneedles (BGC-MNs) were prepared to treat psoriasis by removing cfDNA from the dermis through the skin barrier. The effects of chitosan with different bisguanidine contents on DNA-binding capacity, biocompatibility, and inflammation inhibition were compared, revealing that chitosan containing 20% bisguanidine (BGC2) was found to have the best overall performance. In vitro, BGC2 effectively cleared cfDNA and inhibited the production of inflammatory factors. BGC-MN made from BGC2 had good mechanical and solubility properties. In vivo, BGC-MNs cleared cfDNA, reduced the level of inflammatory factors in the dermis, and exerted a good therapeutic effect on mice with psoriasis. These results suggested that BGC-MNs provided a new approach to treating psoriasis in terms of scavenging cfDNA and exerting anti-inflammatory effects.

A Nanoinhibitor Targeting cGAS-STING Pathway to Reverse the Homeostatic Imbalance of Inflammation in Psoriasis

Psoriasis is a chronic skin inflammation characterized by dysregulated crosstalk between immune cells and keratinocytes. Here we show that the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway is a key regulator of psoriatic inflammation in a mouse model. Platinum-doped positively charged carbon dots (Pt-CDs) were designed to inhibit the cGAS-STING pathway. By inhibiting the cGAS-STING pathway with Pt-CDs, the secretion of proinflammatory cytokines in macrophages was reduced, and the proinflammatory cytokines-induced breakdown of immunological tolerance and overexpression of chemokines in keratinocytes was restored, which reversed the homeostatic imbalance through breaking these cytokines-mediated intercellular positive feedback loop. Topical Pt-CDs treatment exhibited therapeutic effects in imiquimod-induced psoriasis mice without noticeable toxicity. The reversal of elevated expression of STING, phosphorylated STING, and downstream genes within psoriatic lesions indicates that Pt-CDs effectively inhibit the cGAS-STING pathway. This work suggests a promising strategy for psoriasis treatment by targeting the cGAS-STING pathway with Pt-CDs nanoinhibitor to restore skin homeostatic balance.

Label-Free Human Disease Characterization through Circulating Cell-Free DNA Analysis Using Raman Spectroscopy

Circulating cell-free DNA (ccfDNA) is a liquid biopsy biomaterial attracting significant attention for the implementation of precision medicine diagnostics. Deeper knowledge related to its structure and biology would enable the development of such applications. In this study, we employed Raman spectroscopy to unravel the biomolecular profile of human ccfDNA in health and disease. We established reference Raman spectra of ccfDNA samples from healthy males and females with different conditions, including cancer and diabetes, extracting information about their chemical composition. Comparative observations showed a distinct spectral pattern in ccfDNA from breast cancer patients taking neoadjuvant therapy. Raman analysis of ccfDNA from healthy, prediabetic, and diabetic males uncovered some differences in their biomolecular fingerprints. We also studied ccfDNA released from human benign and cancer cell lines and compared it to their respective gDNA, confirming it mirrors its cellular origin. Overall, we explored for the first time Raman spectroscopy in the study of ccfDNA and provided spectra of samples from different sources. Our findings introduce Raman spectroscopy as a new approach to implementing liquid biopsy diagnostics worthy of further elaboration.

The Value of Cell-Free Circulating DNA Profiling in Patients with Skin Diseases

Liquid biopsy, also known as fluid biopsy or fluid-phase biopsy, is the sampling and analysis of the blood, cerebrospinal fluid, saliva, pleural fluid, ascites, and urine. Compared with tissue biopsy, liquid biopsy technology has the advantages of being noninvasive, having strong repeatability, enabling early diagnosis, dynamic monitoring, and overcoming tumor heterogeneity. However, interest in cfDNA and skin diseases has not expanded until recently. In this review, we present an overview of the literature related to the basic biology of cfDNA in the field of dermatology as a biomarker for early diagnosis, monitoring disease activity, predicting progression, and treatment response.

New Perspectives on the Importance of Cell-Free DNA Biology

Body fluids are constantly replenished with a population of genetically diverse cell-free DNA (cfDNA) fragments, representing a vast reservoir of information reflecting real-time changes in the host and metagenome. As many body fluids can be collected non-invasively in a one-off and serial fashion, this reservoir can be tapped to develop assays for the diagnosis, prognosis, and monitoring of wide-ranging pathologies, such as solid tumors, fetal genetic abnormalities, rejected organ transplants, infections, and potentially many others. The translation of cfDNA research into useful clinical tests is gaining momentum, with recent progress being driven by rapidly evolving preanalytical and analytical procedures, integrated bioinformatics, and machine learning algorithms. Yet, despite these spectacular advances, cfDNA remains a very challenging analyte due to its immense heterogeneity and fluctuation in vivo. It is increasingly recognized that high-fidelity reconstruction of the information stored in cfDNA, and in turn the development of tests that are fit for clinical roll-out, requires a much deeper understanding of both the physico-chemical features of cfDNA and the biological, physiological, lifestyle, and environmental factors that modulate it. This is a daunting task, but with significant upsides. In this review we showed how expanded knowledge on cfDNA biology and faithful reverse-engineering of cfDNA samples promises to (i) augment the sensitivity and specificity of existing cfDNA assays; (ii) expand the repertoire of disease-specific cfDNA markers, thereby leading to the development of increasingly powerful assays; (iii) reshape personal molecular medicine; and (iv) have an unprecedented impact on genetics research.

Serum cell-free DNA as a new biomarker in cutaneous T-cell lymphoma

In recent years, circulating cell-free DNA (cfDNA) has received a great attention as a biomarker for various cancers. Many reports have shown that serum cfDNA levels are elevated in cancer patients and their levels correlate with prognosis and disease activity. The aim of this study was to measure serum cfDNA levels in patients with cutaneous T-cell lymphoma (CTCL) and to evaluate their correlations with hematological and clinical findings. Serum cfDNA levels in CTCL patients were significantly higher than those in healthy controls, and their levels gradually increased with the progression of the disease stage. Positive correlations were detected between serum cfDNA levels and those of lactate dehydrogenase, thymus and activation-regulated chemokine and soluble IL-2 receptor as well as neutrophil and eosinophil count in peripheral blood and neutrophil-to-lymphocyte ratio. Furthermore, CTCL patients with higher serum cfDNA levels exhibited a significantly worse prognosis. Taken together, these results suggest the potential of cfDNA as a new biomarker reflecting prognosis and disease activity in CTCL. CfDNA levels may serve as an indicator for considering the intensity and timing of subsequent therapeutic intervention.

Significantly Altered Serum Levels of NAD, AGE, RAGE, CRP, and Elastin as Potential Biomarkers of Psoriasis and Aging—A Case-Control Study

Background: This study aims to investigate potential markers of psoriasis and aging, and to elucidate possible connections between these two processes. Methods: The serum samples of 60 psoriatic patients and 100 controls were analysed, and the levels of four selected parameters (AGEs, RAGE, NAD, and elastin) were determined using commercial ELISA kits. Serum C-reactive protein was assayed using an immune-nephelometry method. Findings: Among the patients, the levels of CRP, AGEs, and RAGE were all increased, while the levels of NAD were reduced when compared to the control group. A negative correlation between the levels of AGEs and NAD was found. A negative correlation between age and the NAD levels among the control group was observed, however among the patients the relationship was diminished. While there was no difference in the levels of native elastin between the patients and the controls, a positive correlation between the levels of native elastin and age and a negative correlation between the levels of native elastin and the severity of psoriasis were found. Conclusions: The results of our study support the notion of psoriasis and possibly other immune-mediated diseases accelerating the aging process through sustained systemic damage. The serum levels of CRP, NAD, AGEs, and RAGE appear to be promising potential biomarkers of psoriasis. The decrease in the serum levels of NAD is associated with (pro)inflammatory states. Our analysis indicates that the levels of native elastin might strongly reflect both the severity of psoriasis and the aging process.

Pathophysiological functions of self-derived DNA

Inflammation plays indispensable roles in building the immune responses such as acquired immunity against harmful pathogens. Furthermore, it is essential for maintaining biological homeostasis in ever-changing conditions. Pattern-recognition receptors (PRRs) reside in cell membranes, endosomes or cytoplasm, and function as triggers for inflammatory responses. Binding of pathogen- or self-derived components, such as DNA, to PRRs activates downstream signaling cascades, resulting in the production of a series of pro-inflammatory cytokines and type I interferons (IFNs). While these series of responses are essential for host defense, the unexpected release of DNA from the nucleus or mitochondria of host cells can lead to autoimmune and autoinflammatory diseases. In this review, we focus on DNA-sensing mechanisms via PRRs and the disorders and extraordinary conditions caused by self-derived DNA.

Cationic Nanomaterials for Autoimmune Diseases Therapy

Cationic nanomaterials are defined as nanoscale structures smaller than 100 nm bearing positive charges. They have been investigated to apply to many aspects including clinical diagnosis, gene delivery, drug delivery, and tissue engineering for years. Recently, a novel concept has been made to use cationic nanomaterials as cell-free nucleic acid scavengers and inhibits the inflammatory responses in autoimmune diseases. Here, we highlighted different types of cationic materials which have the potential for autoimmune disease treatment and reviewed the strategy for autoimmune diseases therapy based on cationic nanoparticles. This review will also demonstrate the challenges and possible solutions that are encountered during the development of cationic materials-based therapeutics for autoimmune diseases.

Psoriasis-Associated Inflammatory Conditions Induce IL-23 mRNA Expression in Normal Human Epidermal Keratinocytes

Psoriasis is a multifactorial, chronic inflammatory skin disease, the development of which is affected by both genetic and environmental factors. Cytosolic nucleic acid fragments, recognized as pathogen- and danger-associated molecular patterns, are highly abundant in psoriatic skin. It is known that psoriatic skin exhibits increased levels of IL-23 compared to healthy skin. However, the relationship between free nucleic acid levels and IL-23 expression has not been clarified yet. To examine a molecular mechanism by which nucleic acids potentially modulate IL-23 levels, an in vitro system was developed to investigate the IL-23 mRNA expression of normal human epidermal keratinocytes under psoriasis-like circumstances. This system was established using synthetic nucleic acid analogues (poly(dA:dT) and poly(I:C)). Signaling pathways, receptor involvement and the effect of PRINS, a long non-coding RNA previously identified and characterized by our research group, were analyzed to better understand the regulation of IL-23 in keratinocytes. Our results indicate that free nucleic acids regulate epithelial IL-23 mRNA expression through the TLR3 receptor and specific signaling pathways, thereby, contributing to the development of an inflammatory milieu favorable for the appearance of psoriatic symptoms. A moderate negative correlation was confirmed between the nucleic-acid-induced IL-23 mRNA level and the rate of its decrease upon PRINS overexpression.

The influence of biological and lifestyle factors on circulating cell-free DNA in blood plasma

Research and clinical use of circulating cell-free DNA (cirDNA) is expanding rapidly; however, there remain large gaps in our understanding of the influence of lifestyle and biological factors on the amount of cirDNA present in blood. Here, we review 66 individual studies of cirDNA levels and lifestyle and biological factors, including exercise (acute and chronic), alcohol consumption, occupational hazard exposure, smoking, body mass index, menstruation, hypertension, circadian rhythm, stress, biological sex and age. Despite technical and methodological inconsistences across studies, we identify acute exercise as a significant influence on cirDNA levels. Given the large increase in cirDNA induced by acute exercise, we recommend that controlling for physical activity prior to blood collection is routinely incorporated into study design when total cirDNA levels are of interest. We also highlight appropriate selection and complete reporting of laboratory protocols as important for improving the reproducibility cirDNA studies and ability to critically evaluate the results.

Genomic landscape of circulating tumour DNA in metastatic extramammary Paget's disease

Although cancer personalized profiling by deep sequencing (CAPP-Seq) of cell-free DNA (cfDNA) has gained attention, the clinical utility of circulating tumour DNA (ctDNA) in extramammary Paget's disease (EMPD) has not been investigated. In this study, genomic alterations in the cfDNA and tumour tissue DNA were investigated in seven patients with metastatic EMPD. CAPP-Seq revealed mutations in 18 genes, 11 of which have not yet been reported in EMPD. The variant allele frequency of some of the mutated genes reflected the disease course in patients with EMPD. In one patient, the mutation was detected even though imaging findings revealed no metastasis. In another patient with triple EMPD (genital area and both axilla), cfDNA sequencing detected the mutation in a rib metastatic lesion, which was also detected in both axilla lesions but not the genital region. Investigations of the ctDNA may be useful towards the elucidation of clonal evolution in EMPD.

Topical cationic hairy particles targeting cell free DNA in dermis enhance treatment of psoriasis

Abnormal high level of cell free DNA (cfDNA) triggers chronic inflammation to exacerbate psoriasis symptoms. Scavenging cfDNA by topical cationic polymeric nanoparticles has been certified as an effective therapeutic strategy for treating psoriasis. However, cationic cfDNA scavengers have a great potential risk to organs after entering systemic circulation through skin barrier. For better transformation to clinical application, herein a series of poly(2-(dimethylamino)ethyl methacrylate) (PDMA) grafted hairy silica particles (cSPs) with tunable PDMA length and particle size are applied to scavenge cfDNA in dermis. We reveal that the structure of cSPs correlates with the permeation ability across stratum corneum, retention time in dermis, binding affinity to cfDNA, and toxicity tolerance, which in turn affect the therapeutic effect. Especially, the cSPs of 700 nm show more accumulation and longer retention in psoriatic lesions, leading to excellent treatment results. They also outperform the cSPs of 200 nm at a lower administration frequency. Thus, we address the issues of size, cationic content of cSPs to open a potential new avenue to topically treatment of psoriasis by targeting cfDNA in dermis.

The Psoriatic Nonlesional Skin: A Battlefield between Susceptibility and Protective Factors

In the last two decades, large-scale gene-expression studies on psoriatic skin samples revealed that even though nonlesional skin is macroscopically identical to healthy skin, it harbors several molecular differences. Originally, these molecular differences were thought to represent susceptibility factors for plaque formation. However, we review in this paper the several factors of immune regulation and structural alteration that are specific for the nonlesional skin and serve as protective factors by counteracting plaque formation and contributing to the maintenance of the nonlesional phenotype.

C-reactive protein, chemerin, fetuin-A and osteopontin as predictors of cardiovascular risks in persons with psoriasis vulgaris

The study aimed to contribute to understanding the role of CRP, chemerin, fetuin-A and osteopontin and to assess their suitability as biomarkers of early stages of cardiovascular diseases in psoriasis vulgaris. Serum levels measured in 28 patients and 22 controls. Patients: increased levels of CRP (p<0.001), chemerin (p<0.05), osteopontin (p<0.05) and decreased levels of fetuin-A (p<0.05), significant relationships between CRP and fetuin-A (rho=0.530, p<0.01), CRP and chemerin (rho=0.543, p<0.01), CRP and age (rho=0.590, p<0.001), osteopontin and fetuin-A (r=-0.415, p<0.05), chemerin and PASI score (rho=-0.424, p<0.05). We confirmed specific roles of the biomarkers in psoriasis. CRP, fetuin-A and osteopontin could be considered appropriate markers for the detection of early stages of cardiovascular diseases.

Aging in psoriasis vulgaris: female patients are epigenetically older than healthy controls

Background

Psoriasis vulgaris is a skin autoimmune disease. Psoriatic patients have significantly lowered life expectancy and suffer from various comorbidities. The main goal of the study was to determine whether psoriatic patients experience accelerated aging. As accelerated aging might be the reason for the higher prevalence of comorbidities at lower chronological ages, we also wanted to investigate the relationship between aging and selected parameters of frequent psoriatic comorbidities - endocan, vascular endothelial growth factor and interleukin-17. Samples were obtained from 28 patients and 42 healthy controls. Epigenetic age measurement was based on the Horvath clock. The levels of endocan, vascular endothelial growth factor and interleukin-17 were analyzed using standardized ELISA methods.

Results

The difference between the epigenetic age and the chronological age of each individual subject did not increase with the increasing chronological age of patients. We cannot conclude that psoriasis causes accelerated aging. However, the epigenetic and chronological age difference was significantly higher in female patients than in female controls, and the difference was correlated with endocan (r = 0.867, p = 0.0012) and vascular endothelial growth factor (r = 0.633, p = 0.0365) only in female patients.

Conclusions

The findings suggest a possible presence of pathophysiological processes that occur only in female psoriatic patients. These processes make psoriatic females biologically older and might lead to an increased risk of comorbidity occurrence. This study also supports the idea that autoimmune diseases cause accelerated aging, which should be further explored in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12979-021-00220-5.

Cell-Free DNA: Hope and Potential Application in Cancer

Cell-free DNA (cfDNA) is easily accessible in peripheral blood and can be used as biomarkers for cancer diagnostics, prognostics, and therapeutics. The applications of cfDNA in various areas of cancer management are attracting attention. In this review article, we discuss the potential relevance of using cfDNA analysis in clinical oncology, particularly in cancer screening, early diagnosis, therapeutic evaluation, monitoring disease progression; and determining disease prognosis.

Circulating Free DNA and Its Emerging Role in Autoimmune Diseases

Liquid biopsies can be used to analyse tissue-derived information, including cell-free DNA (cfDNA), circulating rare cells, and circulating extracellular vesicles in the blood or other bodily fluids, representing a new way to guide therapeutic decisions in cancer. Among the new challenges of liquid biopsy, we found clinical application in nontumour pathologies, including autoimmune diseases. Since the discovery of the presence of high levels of cfDNA in patients with systemic lupus erythaematosus (SLE) in the 1960s, cfDNA research in autoimmune diseases has mainly focused on the overall quantification of cfDNA and its association with disease activity. However, with technological advancements and the increasing understanding of the role of DNA sensing receptors in inflammation and autoimmunity, interest in cfDNA and autoimmune diseases has not expanded until recently. In this review, we provide an overview of the basic biology of cfDNA in the context of autoimmune diseases as a biomarker of disease activity, progression, and prediction of the treatment response. We discuss and integrate available information about these important aspects.

Signaling Through Nucleic Acid Sensors and Their Roles in Inflammatory Diseases

Recognition of pathogen-derived nucleic acids by pattern-recognition receptors (PRRs) is essential for eliciting antiviral immune responses by inducing the production of type I interferons (IFNs) and proinflammatory cytokines. Such responses are a prerequisite for mounting innate and pathogen-specific adaptive immune responses. However, host cells also use nucleic acids as carriers of genetic information, and the aberrant recognition of self-nucleic acids by PRRs is associated with the onset of autoimmune or autoinflammatory diseases. In this review, we describe the mechanisms of nucleic acid sensing by PRRs, including Toll-like receptors, RIG-I-like receptors, and DNA sensor molecules, and their signaling pathways as well as the disorders caused by uncontrolled or unnecessary activation of these PRRs.

Topical nanoparticles interfering with the DNA-LL37 complex to alleviate psoriatic inflammation in mice and monkeys

Cell-free DNA (cfDNA) released from damaged or dead cells combines with LL37 and is converted into an immune response activator to exacerbate psoriasis. Here, we show that cationic nanoparticles (cNPs) efficiently compete for DNA from the DNA-LL37 immunocomplex and inhibit DNA-LL37-induced cell activation. Using phenotypical images, psoriasis area and severity index scoring, histology, and immunohistochemical analysis, we demonstrate that topical application of cNPs on psoriasiform skin of a mouse model relieves psoriatic symptoms. It is noteworthy that the results were confirmed in a cynomolgus monkey model. Moreover, topically administrated cNPs showed low in vivo toxicity because of their retention in skin. Mechanistic analyses of cytokine expression in the psoriatic site, cfDNA levels in circulation and inflamed skin, skin permeation, and biodistribution of cNPs also matched the therapeutic outcomes. Therefore, we present a previously unidentified strategy of nanomedicine to treat skin inflammatory diseases, which demonstrates great potential for clinical application.

Circulating Cell-Free DNA as Inflammatory Marker in Egyptian Psoriasis Patients

Background

Cell lesion and apoptosis with release of cell-free DNA (CFD) in circulation are associated with chronic inflammation of psoriasis.

Objective

The objective of this study was to determine the CFD concentrations in sera of patients with psoriasis, to assess its relationship with disease severity as defined by Psoriasis Area Severity Index (PASI) and other inflammatory biomarkers (C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)) levels, and to monitor the efficacy of treatment.

Patients and Methods

Thirty adult patients with different types of psoriasis (25 vulgaris; 10 mild, 15 moderate and 5 erythroderma; severe) were evaluated during the exacerbation phase of the disease, before starting (T0) and after 12 weeks (T12) of treatment with topical therapy for mild cases, narrowband-ultraviolet light B (NB-UVB) for moderate cases and methotrexate for severe cases. Twenty healthy controls were also involved in the study. The concentrations of CFD in sera were measured before and after treatment by quantitative real time PCR (qPCR) using primers of the human β-globin gene.

Results

At T0, all patients presented significant higher levels of ESR (P=0.05) and CFD (P=0.001) compared with controls. Highly significant elevations of all parameters were observed in severe disease (erythroderma) compared to mild/moderate disease (vulgaris). Methotrexate treatment induced highly significant reductions in all inflammatory markers including CFD (P= 0.042) while topical and UV irradiation therapies had no effects. CFD concentrations showed positive correlations with both PASI (r=0.422, P=0.020) and ESR (r=0.321, P=0.023) only before the start of treatment.

Conclusion

The level of circulating CFD could be used to monitor psoriasis severity. However, its level cannot be stated for the treatment, except in severe erythrodermic patients upon successful treatment with methotrexate. We recommend validation of a convenient and accurate DNA assay applied directly to biological samples which does not require prior DNA extraction and amplification.

Alarmins HMGB1, IL-33, S100A7, and S100A12 in Psoriasis Vulgaris

Background

Psoriasis vulgaris is a chronic autoimmune disease associated with systemic inflammation. Increased levels of numerous cytokines, chemokines, growth factors, and other molecules were found in the skin and in the circulation of psoriatic patients. Alarmins, also known as danger signals, are intracellular proteins, which are released to an extracellular space after infection or damage. They are the markers of cell destructive processes.

Objective

The aim of the present study was to evaluate the suitability of selected alarmins (HMGB1, IL-33, S100A7, and S100A12) as potential biomarkers of severity of psoriasis and to explore possible relationships between these proteins for the purpose of better understanding their roles in the immunopathology of psoriasis.

Methods

The serum levels of selected alarmins were measured in 63 psoriatic patients and 95 control individuals. The levels were assessed by the ELISA technique using commercial kits. The data were statistically processed with MedCalc version 19.0.5.

Results

In psoriatic patients, we found significantly increased levels of HMGB1 (p < 0.05), IL-33 (p < 0.01), S100A7 (p < 0.0001), and S100A12 (p < 0.0001). In addition, we found a significant relationship between HMGB1 and S100A7 (Spearman's rho = 0.276, p < 0.05) in the patients and significant relationship between HMGB1 and IL-33 in the controls (Spearman's rho = 0.416, p < 0.05). We did not find any relationship between observed alarmins and the disease severity.

Conclusions

The alarmins HMGB1, IL-33, S100A7, and S100A12 were significantly elevated in the serum of patients, which states the hypothesis that they play specific roles in the immunopathology of psoriasis. However, we have not yet found a relationship between observed alarmins and the disease severity. The discovery of the relationship between HMGB1 and S100A7 is a novelty that should be studied in the future to further clarify its role and importance.