IL-1 Cytokine Family Research Articles

#4201 DYNAMICS OF INFLAMMATION EARLY AND LATE AFTER RENAL TRANSPLANTATION: CHARACTERIZATION OF THE IMMUNOLOGICAL PROCESSES IN A RAT RENAL TRANSPLANT MODEL

Abstract Background and Aims The pathophysiology of rejection after renal transplantation (RTx) has not been unraveled completely. In previous studies, Th17 cells were shown to be involved in several autoimmune diseases affecting the kidney, e.g. lupus nephritis, glomerulonephritis and ANCA vasculitis. The aim of this study was to decipher the dynamics of rejection after RTx with focus on the Th17 cells and IL17 cytokine family. Method For this purpose, the established Fischer to Lewis rat RTx model was used. In this model, renal rejection is elicited and develops over time. The donor renal grafts were harvested from Fischer rats and exposed to static cold storage using HTK or UW buffer. The Lewis recipients were treated for 10 days post-transplant with ciclosporin A and then immunosuppressive therapy stopped. Recipients were harvested early (2 hours, 30 days) and late after RTx (12 weeks, 28 weeks). To analyze the dynamics of inflammation, kidney sections were stained for CD3+ (T-cells) and MPO (neutrophils). RT-PCR was used to detect cytokine gene expression of several target genes within the renal grafts. IL17A Elispot was established to analyse circulating Th17 cells in the recipients. Results Generally, the cold ischemia time of the renal allograft was associated with the lifetime of the recipients. Furthermore, with increasing cold ischemia time of the graft, intra-renal CD3+ T-cell infiltration was enhanced. An increased CD3+ and a diminished number of MPO+ neutrophils were detected in the renal grafts late after RTx compared to early timepoints. Moreover, the intra-graft IL17C gene expression was enhanced late after renal transplantation while CXCL1 and CXCL2 were upregulated early after renal transplantation. IL17A gene expression reached higher levels than IFNg in later timepoints e.g. 30 days, while in early stages IL17A was below IFNg. The impact of cold storage buffer on the immunogenicity of the renal transplant was investigated, too. The use of UW led to a higher intra-renal CD3+ T-cell infiltration at later timepoints compared with HTK. In early stages after transplantation, higher levels of intra-renal MPO+ neutrophils were found upon cold storage using UW compared to cold storage using HTK. Conclusion The inflammatory process during chronic kidney rejection is T-cell driven and may involve the IL17C cascade. The early phase is dominated by neutrophils with enhanced intra-renal expression of CXCL1 and CXCL2. Furthermore, the polarization of the T-cell driven immune response may change depending on the time point after transplantation.

The Role of Leukemia Inhibitory Factor in Counteracting the Immunopathology of Acute and Chronic Lung Inflammatory Diseases

Leukemia inhibitory factor (LIF), a member of the IL-6 cytokine family, is highly expressed throughout the body in multiple tissues and cell types. LIF is primarily known to induce the differentiation of myeloid leukemia cells, but recent studies show that LIF has many other functions, including playing multiple roles in cancer and normal physiology. LIF expression is linked to cellular proliferation, metastasis, inflammation, and chemoresistance. LIF expression and secretion are triggered by many means and its downstream signaling can vary based on tissue types. Recent publications suggest that LIF may play a role in pulmonary diseases and its regulation is altered through external factors, such as cigarette smoke, inflammation stimuli, or infections. This review outlines the current knowledge of the function of LIF protein, mediators of LIF expression, receptors it interacts with, downstream LIF signaling, and possible pulmonary outcomes mediated by LIF.

Association between the Proinflammatory Cytokine IL-17F and Helicobacter Pylori Infection in a Sample of Iraqi Patients

Background: Infection of the gastric mucosa with Helicobacter pylori (Hp) is characterized by the induction of a number of proinflammatory cytokines, including IL-8, IL-6, and TNF-α, involved in Hp-related gastric inflammation. The functions of members of the IL-17 cytokine family, other than IL-17A, in Hp infection remain understudied. The aim of our study was to assess the association between the proinflammatory cytokine IL-17F and Hp infection in a sample of Iraqi patients. Methods and Results: This study included 50 Iraqi patients (18 males and 32 females; a mean age of 36±1.74 years) infected with Hp. The healthy control group consisted of 16 subjects (3 males and 13 females), with a mean age of 31±2.44 years. For the qualitative detection of antibodies (IgG, IgM, and IgA) against Hp in the serum, we used the OnSite H. pylori Ab Combo Rapid Test (CTK Biotech). ELISA was used to detect levels of human IL-17F in serum using ABTS ELISA Development Kit (Pepro Tech, USA). The serum level of IL-17F in patients with Hp infection was significantly higher than in the control group (238.9±7.64 pg/mL vs. 114.00±3.66 pg/mL, P=0.0001). However, the serum level of IL-17F in Hp patients was not significantly different between men and women (237±12.12 pg/mL and 239±9.94 pg/mL, respectively, P=0.9015). In addition, no significant difference was found between age subgroups: 240±13.18 pg/mL, 231±10.17 pg/mL, and 252±18.35 pg/mL in age subgroups of <30 years, 30-45 years, and >45 years, respectively, (P>0.05). Conclusion: Patients infected with Hp were characterized by higher serum levels of IL-17F than non-Hp subjects. IL-17F plays an important role in the inflammatory response to Hp infection in a sample of Iraqi patients.

Depression, a major comorbidity of psoriatic disease, is caused by metabolic inflammation.

Psoriatic disease is a chronic, systemic immune-mediated inflammatory disorder comprising three major domains, skin, vascular and bone/joint inflammation. It is known for a long time that psoriatic disease is associated with a number of conditions such as hypertension, dyslipidemia, diabetes (metabolic syndrome) and depression. Up to one out of five people with psoriasis show concomitant depression. In the past, this was attributed to psychological stress of suffering from a chronic condition that is often visible and itchy, leading to stigmatization and adding to a significant burden of disease. Recent data provide evidence that depression associated with psoriatic disease is linked to the specific inflammatory pattern with IL-23, IL-17 family cytokines, TNF, IL-6 and IL-8 causing neuroinflammation and subsequently depression or depressive behaviour and/or anxiety. Psoriatic disease shows a distinct pattern of immune cells (e.g. dendritic cells, Th17 cells, neutrophils), mediators (e.g. IL-17A/F, IL-23, TNF) and tissue-related factors in all major domains that is different from other inflammatory dermatoses. There is a striking similarity between the inflammatory pattern in psoriatic disease and neuroinflammation that leads to depression. A number of risk factors have been identified in psoriatic disease, the most important of which are obesity and tobacco smoking. Obesity is known as a major risk factor for depression and anxiety due to its inflammatory signature. Apart from psychotherapy and anti-depressive medication, targeted treatments for psoriasis, including TNF, IL-17 and IL-23 inhibitors, can improve depression/depressive symptoms. The review summarizes the current knowledge about depression as a comorbidity in psoriatic disease.

IL-17C neutralization protects the kidney against acute injury and chronic injury.

Interleukin-17C (IL-17C), a member of the IL-17 cytokine family, plays a pathogenic role in kidney diseases. Our previous studies have shown that pre-administration of IL-17C neutralizing antibody attenuated acute kidney injury (AKI, a common acute inflammation associated renal disease). In this study, we explored whether post-ischemia reperfusion (IR) of IL-17C blockade has therapeutic effects on AKI and whether IL-17C is involved in the pathogenesis of diabetic nephropathy (DN), a major type of chronic inflammation-associated kidney disease. 12-week-old male C57BL/6JGpt mice were treated with IL-17C neutralizing antibody or normal IgG control antibody at 3h after reperfusion. Renal injury, inflammation, and oxidative stress were assessed. Additionally, we examined renal IL-17C expression in patients with DN and db/db mice and evaluated albuminuria, mesangial matrix accumulation and podocyte loss in db/db mice with IL-17C neutralization. Knockdown of NF-κB p65 using siRNA, and blocking Hypoxia-inducible factor-1α (HIF-1α) using YC-1 in mice and HIF-1α Decoy in HK2 cells were investigated to explore the possible signaling pathway involved in IL-17C regulation. We found that delayed IL-17C neutralization had similar reno-protective effects on renal ischemia-reperfusion injury (IRI). Additionally, renal IL-17C expression was increased in patients with DN and db/db mice, while IL-17C blockade significantly attenuated DN, accompanied with blunted albuminuria, mesangial matrix accumulation, and podocyte loss. Moreover, IL-17C neutralization significantly repressed the expression of downstream pro-inflammatory cytokines, inflammatory cell infiltration, and Th17/IL-17A activation both in mice with renal IRI and DN. Mechanistical studies demonstrated that hypoxia or high glucose-induced IL-17C up-regulation was predominantly mediated by NF-κB pathway. IL-17C participates in the pathogenesis of AKI and DN and inhibition of IL-17C shows potential as a therapeutic strategy for AKI and DN. The National Natural Science Foundation of China (81770741, 81700601 and 81870504).

Expression, purification, and biological characterization of recombinant human interleukin-31 protein.

Interleukin-31 (IL-31), belonging to the IL-6 cytokine family, is involved in skin inflammation and pruritus, as well as some tumors' progression. Here, we reported the expression and purification of recombinant human IL-31 (rhIL-31) using a prokaryotic system. This recombinant protein was expressed in the form of inclusion bodies, refolded and purified by size-exclusion chromatography. Circular dichroism analysis revealed that the secondary structure of rhIL-31 was mainly composed of alpha-helix, which is in consistence with the 3D model structure built by AlphaFold server. In vitro studies showed that rhIL-31 exhibited a good binding ability to the recombinant hIL-31 receptor alpha fused with human Fc fragment (rhIL-31RA-hFc) with EC50 value of 16.36µg/mL in ELISA assay. Meanwhile, flow cytometry demonstrated that rhIL-31 was able to bind to hIL-31RA or hOSMRβ expressed on the cell surface, independently. Furthermore, rhIL-31 could induce the phosphorylation of STAT3 in A549 cells. In conclusion, the prepared rhIL-31 in this study possesses the binding ability to its receptors, and can activate the signal pathway of JAK/STAT. Thus, it can be applied in further studies, including investigation of hIL-31-related diseases, structural analysis, and development of therapeutic drugs, and monoclonal antibodies targeting hIL-31.

Cause or consequence? The role of IL-1 family cytokines and receptors in neuroinflammatory and neurodegenerative diseases.

Cytokines and receptors of the IL-1 family are key mediators in innate immune and inflammatory reactions in physiological defensive conditions, but are also significantly involved in immune-mediated inflammatory diseases. Here, we will address the role of cytokines of the IL-1 superfamily and their receptors in neuroinflammatory and neurodegenerative diseases, in particular Multiple Sclerosis and Alzheimer's disease. Notably, several members of the IL-1 family are present in the brain as tissue-specific splice variants. Attention will be devoted to understanding whether these molecules are involved in the disease onset or are effectors of the downstream degenerative events. We will focus on the balance between the inflammatory cytokines IL-1β and IL-18 and inhibitory cytokines and receptors, in view of future therapeutic approaches.

Steady-state memory-phenotype conventional CD4+ T cells exacerbate autoimmune neuroinflammation in a bystander manner via the Bhlhe40/GM-CSF axis

Memory-phenotype (MP) CD4+ T cells are a substantial population of conventional T cells that exist in steady-state mice, yet their immunological roles in autoimmune disease remain unclear. In this work, we unveil a unique phenotype of MP CD4+ T cells determined by analyzing single-cell transcriptomic data and T cell receptor (TCR) repertoires. We found that steady-state MP CD4+ T cells in the spleen were composed of heterogeneous effector subpopulations and existed regardless of germ and food antigen exposure. Distinct subpopulations of MP CD4+ T cells were specifically activated by IL-1 family cytokines and STAT activators, revealing that the cells exerted TCR-independent bystander effector functions similar to innate lymphoid cells. In particular, CCR6high subpopulation of MP CD4+ T cells were major responders to IL-23 and IL-1β without MOG35-55 antigen reactivity, which gave them pathogenic Th17 characteristics and allowed them to contribute to autoimmune encephalomyelitis. We identified that Bhlhe40 in CCR6high MP CD4+ T cells as a key regulator of GM-CSF expression through IL-23 and IL-1β signaling, contributing to central nervous system (CNS) pathology in experimental autoimmune encephalomyelitis. Collectively, our findings reveal the clearly distinct effector-like heterogeneity of MP CD4+ T cells in the steady state and indicate that CCR6high MP CD4+ T cells exacerbate autoimmune neuroinflammation via the Bhlhe40/GM-CSF axis in a bystander manner.

IL-17 cytokines preferentially act on naïve CD4+ T cells with the IL-17AF heterodimer inducing the greatest functional changes.

CD4+ T-helper 17 (Th17) T cells are a key population in protective immunity during infection and in self-tolerance/autoimmunity. Through the secretion of IL-17, Th17 cells act in promotion of inflammation and are thus a major potential therapeutic target in autoimmune disorders. Recent reports have brought to light that the IL-17 family cytokines, IL-17A, IL-17F and IL-17AF, can directly act on CD4+ T-cells, both in murine and human systems, inducing functional changes in these cells. Here we show that this action is preferentially targeted toward naïve, but not memory, CD4+ T-cells. Naïve cells showed transcriptome changes as early as 48 hours post-IL-17 exposure, whereas memory cells remained unaffected as late as 7 days. These functional differences occurred despite similar IL-17 receptor expression on these subsets and were maintained in co-culture/transwell systems, with each subset maintaining its functional response to IL-17. Importantly, there were differences in downstream transcriptional signaling by the three IL-17 cytokines, with the IL-17AF heterodimer conferring both the greatest transcriptional change and most altered functional consequences. Detailed transcriptome analysis provides important insights into the genes and pathways that are modulated as a result of IL-17-mediated signaling and may serve as targets of future therapies.

Abstract 652: Tumor cell-specific IL-1/IL-1R signaling promotes KRAS mutant lung tumorigenesis

Abstract Despite improved diagnosis and treatment strategies such as immunotherapy, lung cancer is still the leading cause of cancer-related deaths worldwide in both men and women. Lung adenocarcinoma (LUAD) with driver mutations in the KRAS oncogene is the most prevalent molecular subtype of lung cancer. KRAS mutant LUAD exhibits aggressive biology in part due to enhanced pro-tumor inflammation mediated by activation of the nuclear factor-κB (NF-κB) and, consequently, elevated expression of various cytokines. While the pro-inflammatory cytokine IL-1β is a product of the NF-κB pathway it also acts as a potent activator, further amplifying the production of protumor cytokines via a positive feedback loop. We have shown that IL-1β blockade enhances anti-tumor immune responses while inhibiting immunosuppression in a mouse model of KRAS mutant LUAD driven by lung epithelial cell-specific expression of KRASG12D (CCSPCre/LSL-KRASG12D, CC-LR mouse). Cell lineage-specific mechanisms that underlie these anti-tumor effects following inhibition of IL-1β are still poorly understood. To fill this void, we here explored the effects of targeting the IL-1R receptor in KRAS mutant lung epithelial cells in the CC-LR mouse model. We studied tumor development and host immune response in 14-week-old CC-LR mice with conditional knockout of IL-1R in KRAS mutant lung epithelial cells (LR/IL-1RΔ/Δ) in comparison to age- and sex-matched control CC-LR littermates. LR/IL-1RΔ/Δ mice displayed markedly reduced tumor multiplicity (~50%) when compared to control CC-LR mice concomitant with decreased cell proliferation and angiogenesis evidenced by attenuated immunohistochemical expression of Ki-67 and ERG. Flow cytometry analysis showed an elevated inflammatory response, most evidently seen through the significant increase in infiltrating monocytes. Interestingly, a shift in type-1 conventional dendritic cells, commonly involved in antigen-cross presentation in tumorigenesis, to type-2 conventional dendritic cells was seen in LR/IL-1RΔ/Δ mice, suggesting a different method of cross-presentation resulting from the conditional knockout of IL-1R that could potentially lead to a protective T-cell response. These results were further confirmed via gene expression analysis of respective markers. Our findings provide further support for the role of the IL-1 cytokine family in the development and progression of KRAS mutant LUAD as well as warrant further studies targeted towards understanding the mechanistic effects IL-1β has on the tumor microenvironment. Citation Format: Avantika Krishna, Michael J. Clowers, Bo Yuan, Milind Mutala, Maria Jose Arredondo Sancristobal, Jocelynn Colunga, Ryan De Maleki, Linda Phan, Humam Kadara, Seyed Javad Moghaddam. Tumor cell-specific IL-1/IL-1R signaling promotes KRAS mutant lung tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 652.

MicroRNAs in inflammasomopathies

microRNAs (miRNAs) are small non-coding RNA sequences that negatively regulate the expression of protein-encoding genes at the post-transcriptional level. They play a role in the regulation of inflammatory responses by controlling the proliferation and activation of immune cells and their expression is disrupted in several immune-mediated inflammatory disorders. Among these, autoinflammatory diseases (AID) are a group of rare hereditary disorders caused by abnormal activation of the innate immune system and characterized by recurrent fevers. Major groups of AID are inflammasomopathies, which are associated with hereditary defects in the activation of inflammasomes, cytosolic multiprotein signaling complexes regulating IL-1 family cytokine maturation and pyroptosis. The study of the role of miRNAs in AID is only recently emerging and remains scarce in inflammasomopathies. In this review, we describe the AID and inflammasomopathies, and the current knowledge on the role of miRNAs in disease processes.

Hyper‐IgE syndrome presenting with early life craniosynostosis in monozygotic twin sisters

<scp>Hyper‐IgE</scp> syndrome presenting with early life craniosynostosis in monozygotic twin sisters

Are IL-1 family cytokines important in management of sickle cell disease in Sub-Saharan Africa patients?

Sickle cell disease (SCD) is the most common genetic disease found in Africa and throughout the world. It is responsible for a high rate of hemolysis, systemic inflammation, and modulation of the immune system with the involvement of immunological molecules, such as cytokines. IL-1β is a major inflammatory cytokine. IL-18 and IL-33, members of IL-1 family, also exhibit characteristics of inflammation-related cytokines. Thus, in order to contribute to the evaluation of the severity and prognosis of SCD in Africa, this study aimed to estimate the cytokine response, in particular the levels of cytokines of the IL-1 family, in sickle cell patients living in a Sub-Saharan country. Ninety patients with a diagnosis of SCD were recruited with different hemoglobin types. Samples were assessed for cytokine levels using the Human Inflammation Panel assay from BioLegend. The assay allows the simultaneous quantification of 13 human inflammatory cytokines/chemokines, i.e., IL-1β, IFN-α2, IFN-γ, TNFα, MCP-1 (CCL2), IL-6, IL-8 (CXCL8), IL-10, IL-12p70, IL-17A, IL-18, IL-23, and IL-33. the assessment of plasma cytokines in SCD patients revealed significantly increased levels of IL-1 family cytokines in crisis compared to steady state, suggesting a substantial involvement of these cytokines in clinical exacerbation. This suggests the possibility of a causal effect in the SCD pathology and can open the way to define better care, pointing toward new therapeutic avenues for sickle disease in Sub-Saharan Africa.

Blood Inflammatory Biomarkers Differentiate Inpatient and Outpatient Coronavirus Disease 2019 From Influenza.

The ongoing circulation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a diagnostic challenge because symptoms of coronavirus disease 2019 (COVID-19) are difficult to distinguish from other respiratory diseases. Our goal was to use statistical analyses and machine learning to identify biomarkers that distinguish patients with COVID-19 from patients with influenza. Cytokine levels were analyzed in plasma and serum samples from patients with influenza and COVID-19, which were collected as part of the Centers for Disease Control and Prevention's Hospitalized Adult Influenza Vaccine Effectiveness Network (inpatient network) and the US Flu Vaccine Effectiveness (outpatient network). We determined that interleukin (IL)-10 family cytokines are significantly different between COVID-19 and influenza patients. The results suggest that the IL-10 family cytokines are a potential diagnostic biomarker to distinguish COVID-19 and influenza infection, especially for inpatients. We also demonstrate that cytokine combinations, consisting of up to 3 cytokines, can distinguish SARS-CoV-2 and influenza infection with high accuracy in both inpatient (area under the receiver operating characteristics curve [AUC] = 0.84) and outpatient (AUC = 0.81) groups, revealing another potential screening tool for SARS-CoV-2 infection. This study not only reveals prospective screening tools for COVID-19 infections that are independent of polymerase chain reaction testing or clinical condition, but it also emphasizes potential pathways involved in disease pathogenesis that act as potential targets for future mechanistic studies.

Human cytomegalovirus pUL97 upregulates SOCS3 expression via transcription factor RFX7 in neural progenitor cells

Congenital human cytomegalovirus (HCMV) infection causes severe damage to the fetal brain, and the underlying mechanisms remain elusive. Cytokine signaling is delicately controlled in the fetal central nervous system to ensure proper development. Here we show that suppressor of cytokine signaling 3 (SOCS3), a negative feedback regulator of the IL-6 cytokine family signaling, was upregulated during HCMV infection in primary neural progenitor cells (NPCs) with a biphasic expression pattern. From viral protein screening, pUL97 emerged as the viral factor responsible for prolonged SOCS3 upregulation. Further, by proteomic analysis of the pUL97-interacting host proteins, regulatory factor X 7 (RFX7) was identified as the transcription factor responsible for the regulation. Depletion of either pUL97 or RFX7 prevented the HCMV-induced SOCS3 upregulation in NPCs. With a promoter-luciferase activity assay, we demonstrated that the pUL97 kinase activity and RFX7 were required for SOCS3 upregulation. Moreover, the RFX7 phosphorylation level was increased by either UL97-expressing or HCMV-infection in NPCs, suggesting that pUL97 induces RFX7 phosphorylation to drive SOCS3 transcription. We further revealed that elevated SOCS3 expression impaired NPC proliferation and migration in vitro and caused NPCs migration defects in vivo. Taken together, these findings uncover a novel regulatory mechanism of sustained SOCS3 expression in HCMV-infected NPCs, which perturbs IL-6 cytokine family signaling, leads to NPCs proliferation and migration defects, and consequently affects fetal brain development.

Cell type specific IL-27p28 (IL-30) deletion in mice uncovers an unexpected regulatory function of IL-30 in autoimmune inflammation

IL-27 is an IL-12 family cytokine with immune regulatory properties, capable of modulating inflammatory responses, including autoimmunity. While extensive studies investigated the major target cells of IL-27 mediating its functions, the source of IL-27 especially during tissue specific autoimmune inflammation has not formally been examined. IL-27p28 subunit, also known as IL-30, was initially discovered as an IL-27-specific subunit, and it has thus been deemed as a surrogate marker to denote IL-27 expression. However, IL-30 can be secreted independently of Ebi3, a subunit that forms bioactive IL-27 with IL-30. Moreover, IL-30 itself may act as a negative regulator antagonizing IL-27. In this study, we exploited various cell type specific IL-30-deficient mouse models and examined the source of IL-30 in a T cell mediated autoimmune neuroinflammation. We found that IL-30 expressed by infiltrating and CNS resident APC subsets, infiltrating myeloid cells and microglia, is central in limiting the inflammation. However, dendritic cell-derived IL-30 was dispensable for the disease development. Unexpectedly, in cell type specific IL-30 deficient mice that develop severe EAE, IL-30 expression in the remaining wild-type APC subsets is disproportionately increased, suggesting that increased endogenous IL-30 production may be involved in the severe pathogenesis. In support, systemic recombinant IL-30 administration exacerbates EAE severity. Our results demonstrate that dysregulated endogenous IL-30 expression may interfere with immune regulatory functions of IL-27, promoting encephalitogenic inflammation in vivo.

The signal transducer and activator of transcription 3 at the center of the causative gene network of the hyper-IgE syndrome.

The hyper-IgE syndrome (HIES) is characterized by atopic dermatitis with extremely high serum IgE levels and diminished inflammatory responses, in combination with bacterial and fungal infections followed by pneumatocele formation. These immunological manifestations are frequently associated with nonimmunological abnormalities, including characteristic face, pathological fracture, and retention of deciduous teeth. We previously identified that major causal variants of the HIES are dominant-negative variants in the signal transducer and activator of transcription 3 (STAT3) gene. Several new causative variants of HIES have been identified, interestingly, most of which are functionally associated with STAT3. These include a zinc finger transcription factor ZNF341 as well as IL-6 family cytokine receptors, IL6ST, and IL-6R. In this review, I will outline the pathological mechanisms of new causative variants, in which STAT3 is at the center of the causative gene network.

Skin Colonization with S. aureus Can Lead to Increased NLRP1 Inflammasome Activation in Patients with Atopic Dermatitis

The role of NLRP1 inflammasome activation and subsequent production of IL-1 family cytokines in the development of atopic dermatitis (AD) is not clearly understood. Staphylococcus aureus is known to be associated with increased mRNA levels of IL1 family cytokines in the skin and more severe AD. In this study, the altered expression of IL-1 family cytokines and inflammasome-related genes was confirmed, and a positive relationship between mRNA levels of inflammasome sensor NLRP1 and IL1B or IL18 was determined. Enhanced expression of the NLRP1 and PYCARD proteins and increased caspase-1 activity were detected in the skin of patients with AD. The genetic association of IL18R1 and IL18RAP with AD was confirmed, and the involvement of various immune cell types was predicted using published GWAS and expression quantitative trait loci datasets. In keratinocytes, the inoculation with S.aureus led to the increased secretion of IL-1β and IL-18, whereas small interfering RNA silencing of NLRP1 inhibited the production of these cytokines. Our results suggest that skin colonization with S.aureus may cause the activation of the NLRP1 inflammasome in keratinocytes, which leads to the secretion of IL-1β and IL-18 and thereby may contribute to the pathogenesis of AD, particularly in the presence of genetic variations in the IL-18 pathway.

IL-33 deficiency suppresses alveolar bone loss in a ligature-induced periodontitis model.

Interleukin-33 (IL-33) is a member of the IL-1 cytokine family that has been studied primarily in the context of type 2 immune responses. Recent reports suggest that IL-33 also enhances the func- tions of various immune cells and contributes to the development of different inflammatory diseas- es. Interestingly, IL-33 and its receptor ST2 axis exerted either inhibitory or promotional effects on alveolar bone loss in various periodontitis models. Using a mouse model of ligature-induced periodontitis, we found that the levels of mRNAs encoding IL-33 and other inflammatory cyto- kines (IL-1α, IL-1β, IL-6, and TNFα) were augmented in gingival tissues of wild-type (WT) mice, and that the alveolar bone loss amount was lower in IL-33-deficient than WT mice. The numbers and proportions of IFN-γ-producing CD8+ T and regulatory T cells were decreased while those of Th17 cells were increased in the draining lymph nodes of IL-33-deficient mice compared to WT mice. Additionally, the level of RNA encoding an osteoclastogenic molecule, i.e., receptor activa- tor of nuclear factor kappa-B ligand (RANKL), in ligated gingival tissue was higher in IL-33-defi- cient than WT mice. These results suggest that IL-33 is involved in alveolar bone loss in the ligature-induced periodontitis model, although IL-33 may inhibit osteoclast differentiation.

Comparative molecular docking analysis for analyzing the inhibitory effect of Anakinra and Ustekinumab against IL17F

Interleukin 17 F is a member of IL-17 cytokine family with a 50% structural homology to IL-17A and plays a significant role either alone or in combination with IL-17A towards inflammation in Rheumatoid arthritis (RA). A growing number of drugs targeting IL-17 pathway are being tested against population specific disease markers. The major objective of this research was to investigate the anti-inflammatory effect of Anakinra (an IL-1 R1 inhibitor) and Ustekinumab (an IL-12 and IL-23 inhibitor) by targeting IL17F. The three dimensional structures of IL17F was taken from PDB while structures of drugs were taken from PubChem database. Docking was performed using MOE and Schrodinger ligand docking software and binding energies, including s-score using London-dG fitness function and glide score using glide internal energy function, between drug and targets were compared. Furthermore, Protein-Drug complex were subjected to 150 ns Molecular Dynamics (MD) Simulations using Schrodinger’s Desmond Module. Docking and MD simulation results suggest anakinra as a more potent IL17F inhibitor and forming a more structurally stable complex. Communicated by Ramaswamy H. Sarma