The role of cAMP dependent gene transcription in lupus pathophysiology

T lymphocytes play a major role in the pathophysiology of systemic lupus erythematosus. T cellular dysregulation includes significant alterations in signal transduction, cytokine production and metabolic pathways. The cAMP dependent transcription factors like CREB and CREM exert pleiotropic functions as they are critically involved in epigenetic conformational changes and gene regulation of different key effector cytokines in CD4+ T cells including that of IL2, IL17 and IL21 genes. In the present review we review current knowledge on altered expression and function of these factors in T cells that promote autoimmunity in SLE patients.

Low-dose interleukin 2 antidepressant potentiation in unipolar and bipolar depression: Safety, efficacy, and immunological biomarkers

Immune-inflammatory mechanisms are promising targets for antidepressant pharmacology. Immune cell abnormalities have been reported in mood disorders showing a partial T cell defect. Following this line of reasoning we defined an antidepressant potentiation treatment with add-on low-dose interleukin 2 (IL-2). IL-2 is a T-cell growth factor which has proven anti-inflammatory efficacy in autoimmune conditions, increasing thymic production of naïve CD4 + T cells, and possibly correcting the partial T cell defect observed in mood disorders. We performed a single-center, randomised, double-blind, placebo-controlled phase II trial evaluating the safety, clinical efficacy and biological responses of low-dose IL-2 in depressed patients with major depressive (MDD) or bipolar disorder (BD). 36 consecutively recruited inpatients at the Mood Disorder Unit were randomised in a 2:1 ratio to receive either aldesleukin (12 MDD and 12 BD) or placebo (6 MDD and 6 BD). Active treatment significantly potentiated antidepressant response to ongoing SSRI/SNRI treatment in both diagnostic groups, and expanded the population of T regulatory, T helper 2, and percentage of Naive CD4+/CD8 + immune cells. Changes in cell frequences were rapidly induced in the first five days of treatment, and predicted the later improvement of depression severity. No serious adverse effect was observed. This is the first randomised control trial (RCT) evidence supporting the hypothesis that treatment to strengthen the T cell system could be a successful way to correct the immuno-inflammatory abnormalities associated with mood disorders, and potentiate antidepressant response.

The effects of low-dose IL-2 on Th17/Treg cell imbalance in primary biliary cholangitis mouse models

BACKGROUND/AIMS

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease. The imbalance of Th17/Treg cells has been reported in PBC patients. Low-dose IL-2 can alleviate disease severity through modulating CD4 + T cell subsets in patients with autoimmune diseases. Hence, the present study aimed to examine the effects and mechanism of low-dose IL-2 in PBC mouse models.

METHODS

PBC models were induced in female C57BL/6 mice by two immunizations with 2OA-BSA at two-week intervals, and poly I: C every three days. PBC mouse models were divided into the IL-2 treated and untreated groups and low-dose IL-2 was injected at three different time points. Th17 and Tregs were analyzed by flow cytometry, and the related cytokines were analyzed by ELISA. Liver histopathology was examined by H&E and immunohistochemical staining.

RESULTS

Twelve weeks after modeling, the serum AMA was positive and the ALP was significantly increased in PBC mouse models (P<0.05). The pathology showed lymphocyte infiltration in the portal area, damage, and reactive proliferation of the small bile duct (P<0.05). The flow cytometric showed the imbalance of Th17/Treg cells in the liver of PBC mouse models, with decreased Treg cells, increased Th17 cells, and Th17/Treg ratio (P < 0.05). After the low-dose IL-2 intervention, biochemical index and liver pathologies showed improvement at 12 weeks. Besides, the imbalance of Th17 and Treg cells recovered. Public database mining showed that Th17 cell differentiation may contribute to poor response in PBC patients.

CONCLUSION

Low-dose IL-2 can significantly improve liver biochemistry and pathology by reversing the imbalance of Th17 and Treg cells, suggesting that it may be a potential therapeutic target for PBC.

Predicting anti-TNF treatment response in rheumatoid arthritis: An artificial intelligence-driven model using cytokine profile and routine clinical practice parameters

Introduction

Rheumatoid arthritis (RA) is a heterogeneous disease in which therapeutic strategies used have evolved dramatically. Despite significant progress in treatment strategies such as the development of anti-TNF drugs, it is still not possible to differentiate those patients who will respond from who will not. This can lead to effective-treatment delays and unnecessary costs. The aim of this study was to utilize a profile of the patient's characteristics, clinical parameters, immune status (cytokine profile) and artificial intelligence to assess the feasibility of developing a tool that could allow us to predict which patients will respond to treatment with anti-TNF drugs.

Methods

This study included 38 patients with RA from the RA-Paz cohort. Clinical activity was measured at baseline and after 6 months of treatment. The cytokines measured before the start of anti-TNF treatment were IL-1, IL-12, IL-10, IL-2, IL-4, IFNg, TNFa, and IL-6. Statistical analyses were performed using the Wilcoxon-Rank-Sum Test and the Benjamini-Hochberg method. The predictive model viability was explored using the 5-fold cross-validation scheme in order to train the logistic regression models.

Results

Statistically significant differences were found in parameters such as IL-6, IL-2, CRP and DAS-ESR. The predictive model performed to an acceptable level in correctly classifying patients (ROC-AUC 0.804167 to 0.891667), suggesting that it would be possible to develop a clinical classification tool.

Conclusions

Using a combination of parameters such as IL-6, IL-2, CRP and DAS-ESR, it was possible to develop a predictive model that can acceptably discriminate between remitters and non-remitters. However, this model needs to be replicated in a larger cohort to confirm these findings.

IL2RA rs2104286 and IL2 rs2069762 polymorphisms may be associated with bipolar disorder and its clinical findings

Study results supported that immuno-inflammatory pathways in the brain and environment contribute to the etiopathogenesis of bipolar disorder (BD), a chronic affective disease. Our study aimed to assess the relationship between BD risk and interleukin 2 (IL2) and interleukin 2 receptor subunit alpha (IL2RA) variants in a Turkish population. Genomic DNA from 86 diagnosed BD patients and 100 healthy blood donors was extracted. IL2RA rs2104286, IL2 rs2069762, and IL2 rs2069763 variants were genotyped using the polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) method. It was compared to the relationship between the genotype distributions of these variants and clinical characteristics. Results were evaluated statistically. A statistically significant difference in the genotype distribution of the IL2RA rs2104286 variant was found between patients and controls. There was no GG genotype in the patient group. The IL2RA rs2104286 AA genotype was more common in the patient group than the controls, and the AG genotype was higher in the controls compared to the patients (p = 0.001, p = 0.001, respectively). The IL2 rs2069762 and IL2 rs2069763 genotype distributions did not differ between the patient and control groups (p > 0.05). We found that the clinical global impression severity (CGI-S) score was higher in those with IL2 rs2069762 TG and GG genotypes. In this study, we showed for the first time that the genotype distribution of IL2RA rs2104286 and IL2 rs2069762 is associated with BD susceptibility and CGI-S score in a Turkish population.

The decreased of peripheral blood natural killer cell is associated with serum IL-2 level in the renal tubular acidosis in patients with primary sjogren's syndrome

BACKGROUND

Primary Sjogren's Syndrome (pSS) is a lymphoproliferative disease with autoimmune characteristics, which is characterized by lymphocyte infiltration of exocrine glands and involvement and dysfunction of extraglandular organs. Renal tubular acidosis (RTA) is a common renal involvement in pSS. This study investigated the phenotypic characteristics of peripheral blood lymphocyte subsets and cytokines in pSS patients complicated with RTA (pSS-RTA).

METHOD

This retrospective study included 25 pSS patients complicated with RTA and 54 pSS patients without RTA (pSS-no-RTA). To examine the level of peripheral lymphocytes subsets, flow cytometry analysis was used. The level of serum cytokines were detected by flow cytometry bead array(CBA). The influencing factors related to the occurrence of pSS-RTA were identified through logistic regression analyze.

RESULTS

The absolute number of CD4 + T cells and Th2 cells in peripheral blood were decreased in pSS-RTA patients than pSS-no-RTA patients. Moreover, the absolute number of NK cells and Treg cells were also decreased in pSS-RTA patients than pSS-no-RTA. The level of serum IL-2 was higher in pSS-RTA patients than pSS-no-RTA patients, and is negatively correlated with the number of NK cells, the number and percentage of Th17 cells, and Th17/Treg. Serum IL-2 level is also correlated with various cytokines. Multivariate logistic analysis proved that elevated ESR and ALP were risk factors for pSS complicated with RTA, while Treg was a protective factor.

CONCLUSION

The increase of serum IL-2 level and the decrease of peripheral blood NK cells and Treg cells may be the immune mechanism of the development of pSS-RTA disease.

Molecular and cognitive signatures of ageing partially restored through synthetic delivery of IL2 to the brain

Cognitive decline is a common pathological outcome during aging, with an ill-defined molecular and cellular basis. In recent years, the concept of inflammaging, defined as a low-grade inflammation increasing with age, has emerged. Infiltrating T cells accumulate in the brain with age and may contribute to the amplification of inflammatory cascades and disruptions to the neurogenic niche observed with age. Recently, a small resident population of regulatory T cells has been identified in the brain, and the capacity of IL2-mediated expansion of this population to counter neuroinflammatory disease has been demonstrated. Here, we test a brain-specific IL2 delivery system for the prevention of neurological decline in aging mice. We identify the molecular hallmarks of aging in the brain glial compartments and identify partial restoration of this signature through IL2 treatment. At a behavioral level, brain IL2 delivery prevented the age-induced defect in spatial learning, without improving the general decline in motor skill or arousal. These results identify immune modulation as a potential path to preserving cognitive function for healthy aging.

Long-term effect of childhood trauma: Role of inflammation and white matter in mood disorders

Bipolar disorder (BD) and major depressive disorder (MDD) are severe psychiatric illnesses that share among their environmental risk factors the exposure to adverse childhood experiences (ACE). Exposure to ACE has been associated with long-term changes in brain structure and the immune response. In the lasts decades, brain abnormalities including alterations of white matter (WM) microstructure and higher levels of peripheral immune/inflammatory markers have been reported in BD and MDD and an association between inflammation and WM microstructure has been shown. However, differences in these measures have been reported by comparing the two diagnostic groups. The aim of the present study was to investigate the interplay between ACE, inflammation, and WM in BD and MDD. We hypothesize that inflammation will mediate the association between ACE and WM and that this will be different in the two groups. A sample of 200 patients (100 BD, 100 MDD) underwent 3T MRI scan and ACE assessment through Childhood Trauma Questionnaire. A subgroup of 130 patients (75 MDD and 55 BD) underwent blood sampling for the assessment of immune/inflammatory markers. We observed that ACE associated with higher peripheral levels of IL-2, IL-17, bFGF, IFN-γ, TNF-α, CCL3, CCL4, CCL5, and PDGF-BB only in the BD group. Further, higher levels of CCL3 and IL-2 associated with lower FA in BD. ACE were found to differently affect WM microstructure in the two diagnostic groups and to be negatively associated with FA and AD in BD patients. Mediation analyses showed a significant indirect effect of ACE on WM microstructure mediated by IL-2. Our findings suggest that inflammation may mediate the detrimental effect of early experiences on brain structure and different mechanisms underlying brain alterations in BD and MDD.

Dietary fats modulate neuroinflammation in mucin 2 knock out mice model of spontaneous colitis

Specific diets regulate neuroimmune responses and modify risk of inflammatory bowel diseases, including ulcerative colitis. A link between gut and brain inflammation is also emerging. We hypothesized that adjusting dietary fatty acid composition modulates the neuroimmune responses in the mucin 2 knock out mice model of spontaneous colitis. Mice were randomly divided into three groups and fed isocaloric diets that only differed in their fatty acid composition. Diets enriched with anhydrous milk fat, corn oil, or Mediterranean diet fats were used. After nine weeks, brain and serum concentrations of ten inflammatory cytokines were measured. Three of these cytokines, including interleukin (IL)-2, IL-12 p70 and interferon-γ, were differentially expressed in the brains of animals from the three diet groups while there were no differences in the serum concentrations of these cytokines. Since only limited information is available about the functions of IL-2 in the central nervous system, in vitro experiments were performed to assess its effects on microglia. IL-2 had no effect on the secretion of neurotoxins and nitric oxide by microglia-like cells, but it selectively regulated phagocytic activity and reactive oxygen species production by stimulated microglia-like cells. Modulation of microglial reactive oxygen species through altered brain IL-2 concentrations could be one of the mechanisms linking diets with modified risk of neuroimmune disorders including Parkinson's disease.

The IL-2 - IL-2 receptor pathway: Key to understanding multiple sclerosis

The development, progression, diagnosis and treatment of autoimmune diseases, such as multiple sclerosis (MS), are convoluted processes which remain incompletely understood. Multiple studies demonstrated that the interleukin (IL)-2 – IL-2 receptor (IL-2R) pathway plays a pivotal role within these processes. The most striking functions of the IL-2 – IL-2R pathway are the differential induction of autoimmune responses and tolerance. This paradoxical function of the IL-2 – IL-2R pathway may be an attractive therapeutic target for autoimmune diseases such as MS. However, the exact mechanisms that lead to autoimmunity or tolerance remain to be elucidated. Furthermore, another factor of this pathway, the soluble form of the IL-2R (sIL-2R), further complicates understanding the role of the IL-2 – IL-2R pathway in MS. The challenge is to unravel these mechanisms to prevent, diagnose and recover MS. In this review, first, the current knowledge of MS and the IL-2 – IL-2R pathway are summarized. Second, the key findings of the relation between the IL-2 – IL-2R pathway and MS have been highlighted. Eventually, this review may launch broad interest in the IL-2 – IL-2R pathway propelling further research in autoimmune diseases, including MS.

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The IL-2 – IL-2R pathway determines the balance between immunity and tolerance.

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The IL-2 – IL-2R pathway is involved in the pathogenesis of multiple sclerosis.

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The role of soluble IL-2R is controversial and requires further investigation.

Exploring the Pathogenic Role and Therapeutic Implications of Interleukin 2 in Autoimmune Hepatitis

Interleukin 2 is essential for the expansion of regulatory T cells, and low-dose recombinant interleukin 2 has improved the clinical manifestations of diverse autoimmune diseases in preliminary studies. The goals of this review are to describe the actions of interleukin 2 and its receptor, present preliminary experiences with low-dose interleukin 2 in the treatment of diverse autoimmune diseases, and evaluate its potential as a therapeutic intervention in autoimmune hepatitis. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Interleukin 2 is critical for the thymic selection, peripheral expansion, induction, and survival of regulatory T cells, and it is also a growth factor for activated T cells and natural killer cells. Interleukin 2 activates the signal transducer and activator of transcription 5 after binding with its trimeric receptor on regulatory T cells. Immune suppressor activity is increased; anti-inflammatory interleukin 10 is released; pro-inflammatory interferon-gamma is inhibited; and activation-induced apoptosis of CD8⁺ T cells is upregulated. Preliminary experiences with cyclic injections of low-dose recombinant interleukin 2 in diverse autoimmune diseases have demonstrated increased numbers of circulating regulatory T cells, preserved regulatory function, improved clinical manifestations, and excellent tolerance. Similar improvements have been recognized in one of two patients with refractory autoimmune hepatitis. In conclusion, interferon 2 has biological actions that favor the immune suppressor functions of regulatory T cells, and low-dose regimens in preliminary studies encourage its rigorous investigation in autoimmune hepatitis.

Use of immunosuppression in non-transplant hepatology

Human liver possesses a persistent and tightly regulated immune response. Maintaining this homeostatic state is the key to prevent pathological processes, as a failure in clearing dangerous stimuli, is associated with tissue damage. A dysregulation of the liver immune homeostasis is involved in many disease processes and the use of the immunosuppression aims to control the inflammatory response, where the physiologic mechanisms failed. The use of steroids which targets broadly the inflammatory cascade and the immune system activation have been extensively employed in both acute and chronic liver diseases. They currently are the backbone of the treatment of autoimmune diseases such as autoimmune hepatitis or IgG4 sclerosing cholangitis. The steroid use in acute liver injury, especially alcohol mediated and drug induced liver injury (DILI), have been debated, despite the biological rationale. The immunosuppression molecules currently employed in liver diseases target the immune system broadly, causing multiple side effects either intrinsic in the mechanisms of the drug or secondary to off-target toxicity. The future of immunosuppressant treatment is moving towards more selective strategies, targeting disease specific pathways. This review aims to explore the rationale of use of immunosuppression in non-transplant hepatology. A broad summary of the immune biology of liver immune mediated diseases will be provided to the readers in order to highlight the potential therapeutic targets. An extensive description of the molecules employed in liver diseases will follow and the clinical evidences in AIH, IgG4 related cholangitis, alcoholic hepatitis and DILI will be reviewed.

Cytokines in the Treatment of Melanoma

PURPOSE OF REVIEW

The use of cytokines in harnessing the immune system to eradicate cancer has been an important treatment modality. However, the dose-limiting toxicities of these cytokines limited their usage in clinic. Here, we review the basic biology of cytokines involved in the treatment of melanoma and discuss their therapeutic applications. Moreover, we describe several innovative technological approaches that have been developed to improve the pharmacokinetics, safety, and efficacy of these cytokines.

RECENT FINDINGS

The safety and the anti-tumor activity of newly engineered cytokines including PEGylated IL-2 (NKTR-214), PEGylated IL-10 (AM0010), and IL-15 super agonist (ALT-803) have been evaluated in clinical trials with encouraging clinical activity and acceptable safety profile, both as single agents and in combination with immuno-oncology agents. A greater understanding of the mechanisms of action and effective dosing of these newly engineered cytokine together with determination of optimum combination therapy regimens may yield greater clinical benefits in the future.

Drug-induced liver injury and prospect of cytokine based therapy; A focus on IL-2 based therapies

Drug-induced liver injury (DILI) is one of the most frequent sources of liver failure and the leading cause of liver transplant. Common non-prescription medications such as non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, and other prescription drugs when taken at more than the recommended doses may lead to DILI. The severity of DILI is affected by factors such as age, ethnicity, race, gender, nutritional status, on-going liver diseases, renal function, pregnancy, alcohol consumption, and drug-drug interactions. Characteristics of DILI-associated inflammation include apoptosis and necrosis of hepatocytes and hepatic infiltration of pro-inflammatory immune cells. If untreated or if the inflammation continues, DILI and associated hepatic inflammation may lead to development of hepatocarcinoma. The therapeutic approach for DILI-associated hepatic inflammation depends on whether the inflammation is acute or chronic. Discontinuing the causative medication, vaccination, and special dietary supplementation are some of the conventional approaches to treat DILI. In this review, we discuss a concise overview of DILI-associated liver complications, and current therapeutic options with special emphasis on biologics including the scope of cytokine therapy in hepatic repair and resolution of inflammation caused by over- the-counter (OTC) or prescription drugs.

A multipurpose brachytherapy catheter to enable intratumoral injection

PURPOSE

To create and test a multipurpose brachytherapy catheter prototype enabling intratumoral injection and brachytherapy after a single catheter insertion.

METHODS AND MATERIALS

The design of the prototype consists of an outer tube and an inner syringe tube that can be filled with injectable agent. The outer sheath and inner syringe tube were constructed using polytetrafluoroethylene tubing, and the other components were 3D printed using dental resin and polylactic acid material. To demonstrate functionality, we injected in vitro phantoms with dyed saline. For proof of concept, we demonstrated the potential for the prototype to deliver cell therapy, enhance tumor delineation, deliver tattoo ink for pathology marking, avoid toxicity through local delivery of chemotherapy, and facilitate combination brachytherapy and immunotherapy.

RESULTS

The prototype enables accurate injection in vitro and in vivo without altering dosimetry. To illustrate the potential for delivery of cell therapies, we injected luciferase-expressing splenocytes and confirmed their delivery with bioluminescence imaging. To demonstrate feasibility of radiographically visualizing injected material, we delivered iohexol contrast intratumorally and confirmed tumor retention using Faxitron x-ray imaging. In addition, we show the potential of intratumoral administration to reduce toxicity associated with cyclophosphamide compared with systemic administration. To demonstrate feasibility, we treated tumor-bearing mice with brachytherapy (¹⁹²Ir source, 2 Gy to 5 mm) in combination with intratumoral injection of 375,000 U of interleukin 2 and observed no increased toxicity.

CONCLUSIONS

These results demonstrate that a prototype multipurpose brachytherapy catheter enables accurate intratumoral injection and support the feasibility of combining intratumoral injection with brachytherapy.

Combination Immunotherapy With LIGHT and Interleukin-2 Increases CD8 Central Memory T-Cells In Vivo

BACKGROUND

The generation of long-term durable tumor immunity and prolonged disease-free survival depends on the ability to generate and support CD8+ central memory T-cells. Microsatellite-stable colon cancer is resistant to currently available immunotherapies; thus, development of novel mechanisms to increase both lymphocyte infiltration and central memory formation are needed to improve outcomes in these patients. We have previously demonstrated that both interleukin-2 (IL-2) and LIGHT (TNFSF14) independently enhance antitumor immune responses and hypothesize that combination immunotherapy may increase the CD8+ central memory T-cell response.

METHODS

Murine colorectal cancer tumors were established in syngeneic mice. Tumors were treated with control, soluble, or liposomal IL-2 at established intervals. A subset of animal tumors overexpressed tumor necrosis superfamily factor LIGHT (TNFSF14). Peripheral blood, splenic, and tumor-infiltrating lymphocytes were isolated for phenotypic studies and flow cytometry.

RESULTS

Tumors exposed to a combination of LIGHT and IL-2 experienced a decrease in tumor size compared with IL-2 alone that was not demonstrated in wild-type tumors or between other treatment groups. Combination exposure also increased splenic central memory CD8+ cells compared with IL-2 administration alone, while not increasing tumor-infiltrating lymphocytes. In the periphery, the combination enhanced levels of circulating CD8 T-cells and central memory T-cells, while also increasing circulating T-regulatory cells.

CONCLUSIONS

Combination of IL-2, whether soluble or liposomal, with exposure to LIGHT results in increased CD8+ central memory cells in the spleen and periphery. New combination immunotherapy strategies that support both effector and memory T-cell functions are critical to enhancing durable antitumor responses and warrant further investigation.

Structural insights into the co-evolution of IL-2 and its private receptor in fish

Interleukin (IL) -2, a member of the four α-helical cytokine family, has broad regulatory roles in mediating vertebrate immune response. In mammals, IL-2 and IL-15 share a common evolutionary origin and possess overlapping but distinct functions. IL-2 and IL-15 bind to distinct private receptors for signaling. However, fish appear to possess a single IL-15Rα like gene whilst lack additional gene(s) coding for IL-2Rα. Whether the IL-2 and IL-15 interact with the same receptor in fish and how their functions and receptors have evolved are not fully understood. In this study, homologues of IL-2 and IL-2/15Rα were sequenced from a teleost species, grass carp (Ctenopharyngodon idella), and the crystal structure of IL-2 was determined. The grass carp IL-2 (termed CiIL-2) displayed a classical cytokine structure consisting of four helical bundles which shares significant similarity with human IL-15. The key amino acids involved in the interface interaction of IL-2/15 and their receptors are well conserved. The CiIL-2 has been shown to bind the IL-2/15Rα like homologue with an affinity of 2.45 nM, supporting the notion that fish IL-2 and IL-15 may share a single common private receptor for exerting functions. Syntenic analysis suggests that the IL-2Rα of tetrapods has evolved from an IL-15Rα like homologue, in which a second sushi domain (D2) in the extracellular region has been duplicated to facilitate the specific interaction with IL-2. The CiIL-2 was predominantly expressed in lymphocyte-rich tissues such as the spleen, kidney and thymus, and could be induced by PHA and IL-21. In vivo challenge with grass carp reovirus and Flavobacterium columnare also resulted in upregulation of CiIL-2 expression. The recombinant CiIL-2 was shown to activate expression of STAT5b, IL-1β, IL-22 and IFN-γ, and to promote the proliferation of the primary cell cultures from head kidney leucocytes. Our results shed lights into the co-evolution of IL-2 and its private receptor, and the functional divergence of IL-2 and IL-15 during evolution.

NK/T cell ratios associate with interleukin-2 receptor alpha chain expression and shedding in multiple sclerosis

NK/T-cell ratios predict disease activity in relapsing remitting multiple sclerosis (RRMS). We investigated in 50 RRMS patients whether interleukin-2 receptor alpha-chain (IL-2Rα) expression and shedding associates with NK/T-cell balance, as suggested by daclizumab-trials in RRMS. A subsample (N = 31) was genotyped for IL2RA-associated MS risk SNPs. CD56^bright NK-cell/IL-17A⁺CD4⁺ T-cell ratios correlated negatively with plasma and PBMC-culture supernatant sIL-2Rα-levels [R = -0.209; p = 0.038 and R = -0.254; p = 0.012, resp.], and with CD4⁺ T-cell CD25 MFI [R = -0.341; p = 0.001]. Carriers of the rs3118470 risk-allele showed higher sIL-2Rα-levels (P = 0.031) and a lower CD56^bright NK-cell/IL-17A⁺CD4⁺ T-cell ratio (P = 0.038). Therefore, IL-2Rα may be involved in the interplay between NK-cells and T-cells.

Inference of molecular structure for characterization and improvement of clinical grade immunocytokines

The use of immunomodulatory agents for the treatment of cancer is gaining a growing biopharmaceutical interest. Antibody-cytokine fusion proteins, namely immunocytokines, represent a promising solution for the regulation of the immune system at the site of disease. The three-dimensional arrangement of these molecules can profoundly influence their biological activity and pharmacokinetic properties. Structural techniques might provide important insight in the 3D arrangement of immunocytokines. Here, we performed structure investigations on clinical grade fusion proteins L19-IL2, IL12-L19L19 and L19L19-IL2 to elucidate their quaternary organization. Crystallographic characterization of the common L19 antibody fragment at a resolution of 2.0-Å was combined with low-resolution studies of the full-length chimeric molecules using small-angle synchrotron X-ray scattering (SAXS) and negative stain electron microscopy. Characterization of the full-length quaternary structures of the immunocytokines in solution by SAXS consistently supported the diabody structure in the L19-IL2 immunocytokine and allowed generation of low-resolution models of the chimeric proteins L19L19-IL2 and IL12-L19L19. Comparison with 3D reconstructions obtained from negative-stain electron microscopy revealed marked flexibility associated to the linker regions connecting the cytokine and the antibody components of the chimeric proteins. Collectively, our results indicate that low-resolution molecular structure characterizations provide useful complementary insights for the quality control of immunocytokines, constituting a powerful tool to guide the design and the subsequent optimization steps towards clinical enhancement of these chimeric protein reagents.

Interleukin 6, soluble interleukin 2 receptor alpha (CD25), monocyte colony-stimulating factor, and hepatocyte growth factor linked with systemic hyperinflammation, innate immunity hyperactivation, and organ damage in COVID-19 pneumonia

Background

Patients infected by SARS-CoV-2 can develop interstitial pneumonia, requiring hospitalisation or mechanical ventilation. Increased levels of inflammatory biomarkers are associated with development of acute respiratory distress syndrome (ARDS). The aim of the present study was to determine which cytokines are associated with respiratory insufficiency in patients hospitalised for COVID-19.

Patients and methods

Data on 67 consecutive patients were collected between March 8 and March 30, 2020. PaO₂/FiO₂ ratio (P/F) was calculated at hospital admission. The following cytokines were analysed: interleukin (IL)-6, IL-1α, IL-18, tumour necrosis factor (TNF)-β, macrophage colony-stimulating factor (M-CSF), macrophage migration inhibitory factor (MIF), soluble IL-2 receptor alpha (sIL-2Rα; CD25), IL-12β, IL-3, interferon (IFN) α2a, monokine induced by gamma interferon (MIG), monocyte-chemotactic protein 3 (MCP3) and hepatocyte growth factor (HGF).

Results

P/F lower than 300 was recorded in 22 out of 67 patients (32.8%). P/F strongly correlated with IL-6 (r = −0.62, P < 0.0001), M-CSF (r = −0.63, P < 0.0001), sIL-2Rα (r = −0.54, P < 0.0001), and HGF (r = −0.53, P < 0.0001). ROC curve analyses for IL-6 (AUC 0.83, 95% CI 0.73–0.93, P < 0.0001), M-CSF (AUC 0.87, 95% CI 0.79–0.96, P < 0.0001), HGF (AUC 0.81, 95% CI 0.70–0.93, P < 0.0001), and sIL-2Rα (AUC 0.80, 95% CI, 0.69–0.90, P < 0.0001) showed that these four soluble factors were highly significant. All four soluble factors correlated with LDH, white blood cell count, neutrophil count, lymphocyte count, and CRP.

Conclusion

IL-6, M-CSF, sIL-2Rα, and HGF are possibly involved in the main biological processes of severe COVID-19, mirroring the level of systemic hyperinflammatory state, the level of lung inflammation, and the severity of organ damage.

Association of interleukin 2, interleukin 12, and interferon-γ with intervertebral disc degeneration in Iranian population

Background

Intervertebral disc degeneration (IVDD) is an age-related degenerative disease, presenting with low back pain or radicular pain. The inflammatory changes would occur in discs in the process of IVDD. Therefore, the inflammatory and anti-inflammatory cytokines, as well as their respective genes, have been proposed to play roles in pathophysiology of disease. This study has been conducted to elucidate the role of IL-2, IL-12, and IFN-γ single nucleotide polymorphisms (SNP) in this disease.

Method

Seventy-six patients who were diagnosed with IVDD and 140 healthy controls who complied with eligibility criteria were included. A total volume of 5 cc peripheral blood was obtained from each participant to investigate the IL-2 + 166G/T, IL-2 -330G/T, IL-12 − 1188A/C, and IFN-γ +847A/T SNPs through PCR-SSP method.

Results

The ‘TG’ and ‘TT’ genotypes of IL-2 − 330G/T polymorphism were significantly more common among patients and healthy controls respectively. The ‘GT’ and ‘TT’ haplotypes of IL-2 (comprised of -330G/T, and + 166G/T SNPs) were also more common among patients and controls respectively.

Conclusion

This study indicated the significant role of IL-2 genotypes and haplotypes in IVDD. These SNPs were differently distributed in patients and controls. Therefore, alteration in the structure of IL-2 gene could play an important role in pathophysiology of IVDD.

Interleukin-2 maintains the survival of interleukin-17+ gamma/delta T cells in inflammation and autoimmune diseases

There is increasing appreciation of the critical pathogenic role of IL-17 in inflammation and autoimmune diseases, which could be produced from both adaptive Th17 cells and innate γδ T cells. Existing evidences suggest that IL-2 is important for in vivo accumulation of IL-17⁺ γδ T cells, leaving the mechanisms still elusive. Herein, using lupus-prone MRL/lpr mice, we demonstrated that splenic γδ T cells were potent IL-17 producers at the onset of lupus, which could be diminished by in vivo IL-2 neutralization. Additional in vivo results showed that neutralization of IL-2 also significantly deleted the IL-17-producing γδ T cells in ovalbumin (OVA) /CFA-immunized B6 mice. Using splenic γδ T cells from OVA/CFA-immunized B6 mice, we further demonstrated that IL-2 could induce IL-17 production alone or together with IL-1β or IL-23 or anti-TCRγδ. Mechanism studies demonstrated that IL-2 could support the survival of γδ T cells, rather than induce the proliferation. Through specific pharmacologic inhibitor, we demonstrated that IL-2 could maintain that RORγt expression of γδ T cells in a STAT5-dependent manner. Collectively, this study suggested that the interplay between IL and 2 and other pro-inflammatory cytokines could trigger the rapid IL-17 production from innate γδ T cells, thus to orchestrate an inflammatory response before the development of adaptive Th17 cells.

The IL-2 - IL-2 receptor pathway in health and disease: The role of the soluble IL-2 receptor

The interleukin (IL)-2 - IL-2 receptor (IL-2R) pathway is important in immunity, but is also involved in maintenance of self-tolerance. This paradox is further complicated by shedding of the IL-2Rα chain, revealing soluble (s)IL-2R. Binding of IL-2 to sIL-2R may either reduce or enhance responses depending on the target cell being involved in immunity or self-tolerance. Since sIL-2R levels are increasingly measured in clinical practice, it is detrimental for clinical interpretation to understand the possible functional impact of IL-2R shedding. In this review the role of the IL-2 - IL-2R pathway is explored and the conflicting results on the function of sIL-2R are summarized. Finally, the added value of measuring sIL-2R in different types of diseases is being elaborated upon in terms of diagnosis, follow-up, and prognosis. Adequate interpretation of results is hampered by the apparent gap in our knowledge about the functional role of sIL-2R in immunity and tolerance.

Abundant CD8+ tumor infiltrating lymphocytes and beta-2-microglobulin are associated with better outcome and response to interleukin-2 therapy in advanced stage clear cell renal cell carcinoma

Studies assessing tumor-infiltrating lymphocytes (TILs) in clear cell renal cell carcinoma (ccRCC) and clinical outcomes have mixed results. Given fundamental interaction of MHC class I with CD8+ T-cells, we hypothesized that expression of MHC class I associated protein, beta-2-microglobulin (B2M), may be an important immunologic marker in RCC. We sought to understand potential implications of CD8 + TILs and tumor B2M expression on overall survival and response to high-dose interleukin-2 (IL-2) therapy, in a cohort of patients with high-stage (clinical stage III and IV) ccRCC. Four tumor regions from 56 patients with ccRCC were retrospectively assessed immunohistochemically. At a median follow-up time of 33 months, 22 (39%) patients had died of disease, 23 (41%) were alive disease, and 11 (20%) had no evidence of disease. Tumors with high CD8 + TILs had a significantly lower death rate [hazard ratio (HR): 0.33, p = 0.02]. CD8 + TILs correlated with B2M expression (p = 0.007). On multivariable analyses, patients with both high B2M and CD8 + TILs had lower death rate (HR: 0.27, p = 0.03). Within the subgroup treated with IL-2 (n = 27, 48%), tumors with high CD8 + TILs were more likely to respond to IL-2 therapy [coefficient (coef): 1.6, p = 0.05]. On multivariable analyses, tumors with a combination of both high B2M expression and high CD8 + TILs also showed trend to responding to IL-2 therapy (coef: 2.5, p = 0.06). In conclusion, abundant CD8+ TILs and high tumor expression of beta-2-microglobulin were good prognostic indicators associated with longer survival in patients with high-stage ccRCC. Abundant CD8+ TILs may predict response to IL-2 therapy.

Combination of three adjuvants enhances the immunogenicity of a recombinant protein containing the CTL epitopes of non-structural proteins of hepatitis C virus

Hepatitis C virus (HCV) can cause chronic infection and evade the immune response. The generation and maintenance of an effective T-cell response is important for immune-mediated control of HCV infection. The purpose of this study was to obtain recombinant mosaic proteins containing the cytotoxic T lymphocyte (CTL) epitopes of HCV fused with different adjuvants and analyse their immunogenicity. A recombinant polyepitope protein comprising HLA-A2-restricted CTL epitopes of the NS3, NS4ab and NS5a proteins of HCV was designed. Adjuvant compounds, the T-helper (Th) epitope PADRE, lipopeptide from Neisseria meningiditis and interleukin 2 (IL-2) were included in the fusion proteins. Three proteins differing in their adjuvant content were expressed in Escherichia coli and purified. The purified proteins formed nanosized particles. The proteins were characterized by their ability to cause proliferation of spleen cells, induce expression of cytokine genes and production of interferon gamma by T lymphocytes of immunized mice. The obtained recombinant vaccine proteins effectively stimulate dendritic cells, which in turn specifically activate Th1 and Th2 lymphocytes. Adjuvant components act additively to enhance the stimulation of dendritic cells and polarize them in the direction of Th1 lymphocyte activation. Analysis of spleen cell proliferation, expression of Th1 and Th2 cytokines and production of interferon gamma by lymphocytes of immunized mice after specific stimulation in vitro revealed that recombinant protein comprising CTL epitopes of HCV, Th epitope PADRE, lipoprotein and IL-2 induced the highest response of T-lymphocytes.

Interleukin-2 induces extracellular matrix synthesis and TGF-β2 expression in retinal pigment epithelial cells

Macular fibrosis is a vital obstacle of vision acuity improvement of age‐related macular degeneration patients. This study was to investigate the effects of interleukin 2 (IL‐2) on epithelial‐mesenchymal transition (EMT), extracellular matrix (ECM) synthesis and transforming growth factor β2 (TGF‐β2) expression in retinal pigment epithelial (RPE) cells. 10 μg/L IL‐2 was used to induce fibrosis in RPE cells for various times. Western blot was used to detect the EMT marker α‐smooth muscle actin (α‐SMA), ECM markers fibronectin (Fn) and type 1 collagen (COL‐1), TGF‐β2, and the activation of the JAK/STAT3 and NF‐κB signaling pathway. Furthermore, JAK/STAT3 and NF‐κB signaling pathways were specifically blocked by WP1066 or BAY11‐7082, respectively, and the expression of α‐SMA, COL‐1, Fn and TGF‐β2 protein were detected. Wound healing and Transwell assays were used to measure cell migration ability of IL‐2 with or without WP1066 or BAY11‐7082. After induction of IL‐2, the expressions of Fn, COL‐1, TGF‐β2 protein were significantly increased, and this effect was correlated with IL‐2 treatment duration, while α‐SMA protein expression did not change significantly. Both WP1066 and BAY11‐7082 could effectively downregulate the expression of Fn, COL‐1 and TGF‐β2 induced by IL‐2. What's more, both NF‐κB and JAK/STAT3 inhibitors could suppress the activation of the other signaling pathway. Additionally, JAK/STAT3 inhibitor WP1066 and NF‐κB inhibitor BAY 11‐7082 could obviously decrease RPE cells migration capability induced by IL‐2. IL‐2 promotes cell migration, ECM synthesis and TGF‐β2 expression in RPE cells via JAK/STAT3 and NF‐κB signaling pathways, which may play an important role in proliferative vitreoretinopathy.

In vitro cytotoxic effect of Trastuzumab in combination with Pertuzumab in breast cancer cells is improved by interleukin-2 activated NK cells

Targeting erb-b2 receptor tyrosine kinase 2 (ERBB2) using the combination of Trastuzumab and Pertuzumab has demonstrated promising results in breast cancer therapy. It has further been revealed that interleukin-2 (IL-2) can activate Natural Killer cells (NK cells) and elevate their cytotoxic potency against tumor cells. In this study, we explored the cytotoxic effect of recombinant human IL-2 in combination with Trastuzumab and Pertuzumab on the ERBB2 positive (SK-BR-3) and negative (MDA-MB-231) breast cancer cell lines. The cytotoxicity level of IL-2 activated NK cells (approximately 75%) were significantly higher than untreated cells (approximately 55%) in the presence of Trastuzumab and Pertuzumab against SK-BR-3 cells, while no difference was observed in the case of MDA-MB-231 cells (about 15%).

Melibiosamine, a novel oligosaccharide, suppresses mitogen-induced IL-2 production via inactivation of NFAT and NFκB in Jurkat cells

d-Glucosamine (GlcNH₂) and several of its derivatives are known to possess immunosuppressive activities in various immune cell lines. The novel GlcNH₂-containing oligosaccharide Galα1-6GlcNH₂ (designated melibiosamine; MelNH₂) is expected to be immunosuppressive also. In Jurkat cells (immortalized human T lymphocytes), interleukin 2 (IL-2) production (an index of the T-cell immune response) can be induced by stimulation with a mitogen, such as concanavalin A. Here, we compared the effects of GlcNH₂ and MelNH₂ on concanavalin A-induced IL-2 production (CIIP) in Jurkat cells and found that GlcNH₂ and MelNH₂ at millimolar levels both significantly suppressed CIIP without affecting cell viability. When we examined the effects of GlcNH₂ and MelNH₂ on the activation of the three transcription factors required for CIIP—NFAT (nuclear factor of activated T-cells), NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells), and AP-1 (activator protein 1)—we found that GlcNH₂ and MelNH₂ both suppressed CIIP by inhibiting the activation of NFAT and NFκB, but, unlike GlcNH₂, MelNH₂ also promoted the activation of AP-1. These results suggest that MelNH₂ may be a potentially useful lead compound for development as an immunosuppressive or anti-inflammatory drug.

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Immunosuppressive effects of MelNH₂ (Galα1-6GlcNH₂) were examined in Jurkat cells.

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Concanavalin A induces IL-2 production in Jurkat cells.

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MelNH₂ at millimolar levels dose-dependently suppressed ConA-induced IL-2 production.

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MelNH₂ inhibited the activation of NFAT and NFκB, which control IL-2 expression.

Regulation of FOXP3 expression in myeloid cells in response to all-trans-retinoic acid, interleukin 2 and transforming growth factor β

FoxP3 is a transcription factor essential for differentiation and function of T regulatory cells (Tregs). There are two major subsets of Tregs: natural Tregs (nTregs) generated in thymus and inducible Tregs (iTregs) produced in peripheral immune system. It has been documented that iTreg development is dependent on soluble mediators including interleukin 2 (IL2), transforming growth factor β (TGFβ) and all-trans-retinoic acid (ATRA). In our experiments we performed a gene expression array, followed by Real-time PCR experiments to study expression of genes regulated by ATRA in cells of myeloid origin. Our experiments revealed that ATRA alone, but also a cocktail of mediators consisting of IL2, TGFβ and ATRA, upregulate expression of FOXP3 gene in normal and leukemic myeloid cells. Our results indicate that signaling pathways which are used at the late steps of T cell differentiation, are also active in the cells of myeloid lineage.

Structure and Function of an Inflammatory Cytokine, Interleukin-2, Analyzed Using the Bioinformatic Approach

The inflammatory cytokine, interleukin-2 (IL-2), is an important regulator of cellular functions. This relatively less studied member of the interleukin protein family is responsible for multiple immuno-modulatory and immuno-stimulatory tasks, like T cell activation, triggering of natural killer cells, inflammation, as well as proliferation and progression of autoimmune diseases and cancers. In this communication we report the temporally variant structural aspects of the IL-2 ligand and its receptor interfaces, based on the available crystal structures. The intended goal of this effort is to generate simulated results that could potentially aid the designs of novel structure based therapeutics.

Y75B8A.8 (HC8) protein of Haemonchus contortus: A functional inhibitor of host IL-2

Interleukin 2 (IL-2) is an important immune regulatory factor in the immune response of the host. However, little is known about the inhibitor of host IL-2 in Haemonchus contortus infection. In this study, we found that globin domain-containing protein (HCGB) and Protein Y75B8A.8 (HC8) from H contortus excretory and secretory products are two binding proteins of IL-2 in goats. The yeast two-hybrid screening further validated the positive interactions of IL-2 with HCGB and HC8. Meanwhile, we found that HC8 had inhibitory effects on IL-2-induced peripheral blood mononuclear cell (PBMC) proliferation, while HCGB did not. Furthermore, transcriptional analysis revealed that HC8 could block the IL-2-activated signalling pathway. Our results showed that HC8 was a functional inhibitor of goat IL-2.

Statins, metformin, proprotein-convertase-subtilisin-kexin type-9 (PCSK9) inhibitors and sex hormones: Immunomodulatory properties?

The immune system is closely intertwined with the endocrine system. Many effects of medications used for various clinical endocrine conditions such as the metabolic syndrome, hypercholesterolemia, diabetes mellitus, hypertension, Graves' disease and others also have an impact on the immune system. Some drugs including statins, metformin, angiotensin converting enzyme and proprotein-convertase-subtilisin-kexin type-9 (PCSK9) inhibitors and sex hormones are known to have immunomodulatory properties. We here review the literature on this topic and provide some clinical examples including the use of statins in Graves' orbitopathy, rheumatoid arthritis, multiple sclerosis, and adult-onset Still's disease. In that context, we introduce a special immunodiagnostics method developed at the Institute of  Diabetes "Gerhardt Katsch" in Karlsburg, Germany, to not only measure but also monitor immune disease activity.

Single nucleotide polymorphisms of IL-2, but not IL-12 and IFN-γ, are associated with increased susceptibility to chronic spontaneous urticaria

BACKGROUND

A clear picture of interaction of Th1/Th2 cytokines in pathogenesis of chronic spontaneous urticaria (CSU), remains elusive. Impaired IFN-γ production and decreased levels of IL-2 have been reported. The aim of this study was to evaluate the association of Th1 cytokines; IL-2, IL-12 and IFN-γ polymorphisms with CSU.

METHODS

90 patients with CSU and 140 age-sex matched subjects were included in this study. DNA samples were evaluated through PCR-SSP assay in order to detect single nucleotide polymorphisms of IL-12 (A/C -1188) or (rs3212227), IFN-γ (A/T UTR5644) or (rs2069717) and IL-2 (G/T -330 and G/T +166) or (rs2069762 and rs2069763).

RESULTS

G allele at -330 at promoter region of IL-2 gene was overrepresented in CSU. Heterozygotes (GT) at this locus and heterozygotes at +166 of IL-2 gene (GT) were more prevalent in CSU group. Additionally, the haplotype GT for loci -330 and +166 of IL-2 gene was powerfully associated with CSU (OR (95%CI)=57.29 (8.43-112.7)).

CONCLUSIONS

SNP at position -330 and +166 of IL-2 gene are differently expressed in CSU. The haplotype GT of IL-2 at -330 and +166 might confer vulnerability to a number of immunological disorders in Iranian region.

An upregulation of CD8+CD25+Foxp3+ T cells with suppressive function through interleukin 2 pathway in pulmonary arterial hypertension

Accumulating evidence suggests that abnormal inflammation plays a critical role in the pathogenesis of pulmonary arterial hypertension (PAH). CD8⁺CD25⁺Foxp3⁺ T cell is a novel cell subtype, and its role in PAH is not yet investigated. Here, we observed that PAH patients presented a significant upregulation of CD8⁺CD25⁺Foxp3⁺ T cells and a downregulation of CD4⁺CD25⁺Foxp3⁺ T cells compared to healthy controls. Regardless, the total number of CD25⁺Foxp3⁺ T cells in PAH patients was still smaller than that in healthy controls. Compared to CD8⁺CD25^- T cells, CD8⁺CD25⁺ T cells presented higher Foxp3 expression, lower interferon (IFN)-γ expression and higher transforming growth factor (TGF)-β expression, in both healthy and PAH individuals. The CD8⁺CD25⁺ T cells in PAH patients also demonstrated regulatory function by suppressing the proliferation of CD4⁺CD25^- and CD8⁺CD25^- effector T cells, albeit at lower efficiency than CD4⁺CD25⁺ T cells from PAH patients and healthy volunteers. CD8⁺CD25⁺ T cells from PAH responded to interleukin (IL)-2 supplement by expansion and upregulating Foxp3 expression. In PAH patients, IL-2-treated CD8⁺CD25⁺ T cells were more potent at inhibiting CD4⁺CD25^- effector T cell proliferation than IL-2-untreated CD8⁺CD25⁺ T cells. Together, we found an upregulation of CD8⁺CD25⁺Foxp3⁺ T cells in PAH patients, and this T cell population presented suppressive activity that could be enhanced by IL-2 treatment.

Interleukin 2 and interleukin 10 function synergistically to promote CD8+ T cell cytotoxicity, which is suppressed by regulatory T cells in breast cancer

The precise role of interleukin (IL)-10 in breast cancer is not clear. Previous studies suggested a tumor-promoting role of IL-10 in breast cancer, whereas recent discoveries that IL-10 activated and expanded tumor-resident CD8+ T cells challenged the traditional view. Here, we investigated the role of IL-10 in HLA-A2-positive breast cancer patients with Grade III, Stage IIA or IIB in-situ and invasive ductal carcinoma, and compared it with that of IL-2, the canonical CD8+ T cell growth factor. We first observed that breast cancer patients presented higher serum levels of IL-2 and IL-10 than healthy controls. Upon prolonged TCR stimulation, peripheral blood CD8+ T cells from breast cancer patients tended to undergo apoptosis, which could be prevented by the addition of IL-2 and/or IL-10. The cytotoxicity of TCR-activated CD8+ T cells was also enhanced by exogenous IL-2 and/or IL-10. Interestingly, IL-2 and IL-10 demonstrated synergistic effects, since the enhancement in CD8+ T cell function when both cytokines were added was greater than the sum of the improvements mediated by each individual cytokine. IL-10 by itself could not promote the proliferation of CD8+ T cells but could significantly enhance IL-2-mediated promotion of CD8+ T cell proliferation. In addition, the cytotoxicity of tumor-infiltrating CD8+ T cells in breast tumor was elevated when both IL-2 and IL-10 were present but not when either one was absent. This synergistic effect was stopped by CD4+CD25+ regulatory T cells (Treg), which depleted IL-2 in a cell number-dependent manner. Together, these results demonstrated that IL-2 and IL-10 could work synergistically to improve the survival, proliferation, and cytotoxicity of activated CD8+ T cells, an effect suppressible by CD4+CD25+ Treg cells.

Possible link of Interleukin-6 and Interleukin-2 with psychiatric diagnosis, ethnicity, disaster or BMI

BACKGROUND

Cytokines are of increasing interest as markers for stress responses, mental disorders and general health. We assessed associations of two cytokines with several factors among relocated hurricane survivors and controls.

METHODS

We examined 40 relocated hurricane survivors and 40 demographically matched (frequency matching) Oklahoma controls to assess relationships of Interleukin-2 (IL-2) and Interleukin-6 (IL-6) with psychiatric diagnoses (SCID-IV), demographic variables, hurricane exposure and body mass index (BMI). Participants were predominantly African American (n=70, 87.5%).

RESULTS

Relocated Katrina survivors had higher proportions of current PTSD, major depression and psychiatric diagnoses than controls. Unexpectedly, exposure to Katrina with relocation was not by itself associated with differences in IL-2 or IL-6 levels. The mean IL-2 level was significantly higher in African American participants than other ethnicities (8 Caucasians, 2 Asians) and in those with a current psychiatric disorder. The mean IL-6 level was higher in females than males and in participants with any current psychiatric diagnosis. IL-6 level also correlated positively with participants' BMI.

CONCLUSIONS

Results suggest that cytokines studied were influenced non-specifically by the presence of a mental disorder, and by demographic variables of gender, ethnicity and BMI. Implications of these findings are discussed, as well as possible long-term impact of the identified interleukin differences on immunologic, inflammatory, neuropsychiatric and other systems.

NK cell effector functions in a Chédiak-Higashi patient undergoing cord blood transplantation: Effects of in vitro treatment with IL-2

NK cell cytotoxicity in Chédiak-Higashi syndrome (CHS) is strongly impaired as lytic granules are not released upon NK-target cell contact, contributing to several defects typical of this severe immunodeficiency. Correction of NK cell defects in CHS should improve the outcome of hematopoietic stem-cell transplantation, proposed as therapy. We investigated NK cell functions in a CHS patient before and after cord-blood transplantation, and the ability of in vitro IL-2 treatment to restore them. Before the transplant, the strong defect in NK cell-mediated natural and antibody-dependent cytotoxicity, as well as in IFN-γ production, could be restored up to normal levels by in vitro IL-2 treatment. This cytokine also caused the appearance of smaller lysosomal granules and their orientation towards the NK-target cell contact area, thus suggesting that IL-2 had a more general capacity to restore NK cell effector functions. Moreover after the transplant, although the successful engraftment, NK cell cytotoxicity resulted still partially impaired at one year, almost normal at ten years and, anyhow, fully recovered by in vitro IL-2 treatment. Taken together, our results indicate that IL-2 had a wide capacity to restore NK cell effector functions, being able to reverse the altered cytotoxic activity, lytic granule pattern, and cytokine production observed in the CHS patient.

Anti-inflammatory effects of novel barbituric acid derivatives in T lymphocytes

We have used a high throughput small molecule screen, using a fission yeast-based assay, to identify novel phosphodiesterase 7 (PDE7) inhibitors. One of the most effective hit compounds was BC12, a barbituric acid-based molecule that exhibits unusually potent immunosuppressive and immunomodulatory actions on T lymphocyte function, including inhibition of T cell proliferation and IL-2 cytokine production. BC12 treatment confers a >95% inhibition of IL-2 secretion in phytohaemagglutinin (PHA) plus phorbol-12-myristate-13-acetate (PMA) stimulated Jurkat T cells. The effect of BC12 on IL-2 secretion is not due to decreased cell viability; rather, BC12 blocks up-regulation of IL-2 transcription in activated T cells. BC12 also inhibits IL-2 secretion in human peripheral T lymphocytes stimulated in response to CD3/CD28 co-ligation or the combination of PMA and ionomycin, as well as the proliferation of primary murine T cells stimulated with PMA and ionomycin. A BC12 analog that lacks PDE7 inhibitory activity (BC12-4) displays similar biological activity, suggesting that BC12 does not act via PDE7 inhibition. To investigate the mechanism of inhibition of IL-2 production by BC12, we performed microarray analyses using unstimulated and stimulated Jurkat T cells in the presence or absence of BC12 or BC12-4. Our studies show these compounds affect the transcriptional response to stimulation and act via one or more shared targets to produce both anti-inflammatory and pro-stress effects. These results demonstrate potent immunomodulatory activity for BC12 and BC12-4 in T lymphocytes and suggest a potential clinical use as an immunotherapeutic to treat T lymphocyte-mediated diseases.

Dinutuximab for the treatment of pediatric patients with high-risk neuroblastoma

Neuroblastoma (NB) is the most common extra cranial solid tumor of childhood, with 60% of patients presenting with high risk (HR) NB by means of clinical, pathological and biological features. The 5-year survival rate for HR-NB remains below 40%, with the majority of patients suffering relapse from chemorefractory tumor. Immunotherapy is the main strategy against minimal residual disease and clinical experience has mostly focused on monoclonal antibodies (MoAb) against the glycolipid disialoganglioside GD2. Three anti-GD2 antibodies have been tested in the clinic including murine 14G2a, human-mouse chimeric ch14.18 and 3F8. Anti-GD2 MoAb induces cellular cytoxicity against NB and is most effective when effector cells like natural killer cells, granulocytes and macrophages are amplified by cytokines. The combination of cytokines IL-2 and GM-CSF with the anti-GD2 MoAb ch14.18 (Dinutuximab) has shown a significant improvement in outcome for HR-NB. The FDA and EMA approved dinutuximab (Unituxin(R)) in 2015 for the treatment of patients with HR-NB who achieved at least a partial response after multimodality therapy.

Significant hepatic expression of IL-2 and IL-8 in biliary atresia compared with other neonatal cholestatic disorders

OBJECTIVES

Although the exact etiology of biliary atresia (BA) is still elusive, inflammation plays a key role. Release of proinflammatory cytokines from activated immune cells perpetuates the injury and causes biliary destruction. We aimed to study interleukin (IL)-2 and IL-8 expression in liver tissue of BA patients compared with other neonatal cholestatic disorders.

METHODS

The study included 59 infants with neonatal cholestasis in two groups; BA group (n=31) and non-BA group (n=28) with cholestatic disorders other than BA as controls. Demographic, clinical, laboratory, and histopathological parameters were collected. IL-2 and IL-8 immunostaining was performed. Immunostaining in portal cellular infiltrate was scored as positive or negative and expressed as the mean cell count in three portal tracts.

RESULTS

The mean value of IL-2 and IL-8 positive inflammatory cells was significantly higher in BA than in non-BA group (P-values of 0.004 and 0.002 respectively). IL-2 correlated significantly with IL-8 immunostaining in both BA and non-BA group (P<0.0001 for both). Furthermore, both cytokines in both groups correlated significantly with inflammatory activity in liver biopsy while there was no significant correlation with the other studied parameters. Yet, there was a trend of increased expression of IL-2 and IL-8 with increasing stage of fibrosis in BA group. This trend was not observed in non-BA group.

CONCLUSION

The significantly higher expression of IL-2 and IL-8 in patients with BA compared to non-BA suggests a potential role for these cytokines in the pathogenesis in therapy of this devastating neonatal hepatic disorder.

Increased interleukin-2 serum levels were associated with psychopathological symptoms and cognitive deficits in treatment-resistant schizophrenia

Accumulating evidence showed that interleukin-2 (IL-2) may be involved in the pathophysiology of schizophrenia. Increased IL-2 levels have been found in the serum of schizophrenia patients with mixed results. In the present study, we assessed serum IL-2 levels in a large group of 160 schizophrenia patients compared to 60 healthy control subjects matched for age and gender. The schizophrenia symptomatology was assessed by the Positive and Negative Syndrome Scale (PANSS), and serum IL-2 levels were measured by sandwich ELISA. The results showed that IL-2 levels were significantly higher in chronic patients with schizophrenia than in healthy control subjects (p<0.001). Correlation analysis revealed a significantly negative association between IL-2 levels and the PANSS cognitive and positive subscales (both p<0.01). Stepwise multiple regression analyses confirmed IL-2 as the influencing factor for the cognitive and positive subscales of the PANSS. Our findings suggested that increased IL-2 may be involved in the cognitive impairments and psychopathology of chronic schizophrenia.

Serum levels of interleukin-2 predict the recurrence of atrial fibrillation after pulmonary vein ablation

AIMS

Interleukin-2 has a significant antitumor activity in some types of cancer, and has been associated with the development of atrial fibrillation (AF). In addition, IL-2 serum levels in recent onset AF have been related with pharmaceutical cardioversion outcomes. We evaluated the hypothesis that a relationship exists between inflammation and the outcome of catheter ablation of AF.

METHODS

We studied 44 patients with paroxysmal AF who underwent catheter ablation. Patients with structural heart disease, coronary artery or valve disease, active inflammatory disease, known or suspected neoplasm, endocrinopathies, or exposure to anti-inflammatory drugs were excluded. All study participants underwent evaluation with a standardized protocol, including echocardiography, and cytokine levels of interleukin-2, interleukin-4, interleukin-6, interleukin-10, tumour necrosis factor-alpha, and gamma-interferon determination before procedure. Clinical and electrocardiographic follow-up were performed with Holter-ECG at 3, 6 and 12months in order to know if sinus rhythm was maintained.

RESULTS

After catheter ablation of the 44 patients included (53±10years, 27.3% female), all patients returned to sinus rhythm. During the first year of follow-up seven patients (15.9%) experienced recurrence of AF. The demographics, clinical and echocardiographic features, and pharmacological treatments of these patients were similar to those who maintained sinus rhythm. The only independent factor predictive of recurrence of AF was an elevated level of IL-2 (OR 1.18, 95% CI 1.12-1.38).

CONCLUSIONS

High serum levels of interleukin-2, a pro-inflammatory non-vascular cytokine, are associated with the recurrence of AF in patients undergoing catheter ablation.

MAC-T cells as a tool to evaluate lentiviral vector construction targeting recombinant protein expression in milk

Prior to generating transgenic animals for bioreactors, it is important to evaluate the vector constructed to avoid poor protein expression. Mammary epithelial cells cultured in vitro have been proposed as a model to reproduce the biology of the mammary gland. In the present work, three lentiviral vectors were constructed for the human growth hormone (GH), interleukin 2 (IL2), and granulocyte colony-stimulating factor 3 (CSF3) genes driven by the bovine β-casein promoter. The lentiviruses were used to transduce mammary epithelial cells (MAC-T), and the transformed cells were cultured on polystyrene in culture medium with and without prolactin. The gene expression of transgenes was evaluated by PCR using cDNA, and recombinant protein expression was evaluated by Western-blotting using concentrated medium and cellular extracts. The gene expression, of the three introduced genes, was detected in both induced and non induced MAC-T cells. The human GH protein was detected in the concentrated medium, whereas CSF3 was detected in the cellular extract. Apparently, the cellular extract is more appropriate than the concentrated medium to detect recombinant protein, principally because concentrated medium has a high concentration of bovine serum albumin. The results suggest that MAC-T cells may be a good system to evaluate vector construction targeting recombinant protein expression in milk.

[Analysis of the molecular characteristics and cloning of full-length coding sequence of interleukin-2 in tree shrews]

While the tree shrew (Tupaia belangeri chinensis) is an excellent animal model for studying the mechanisms of human diseases, but few studies examine interleukin-2 (IL-2), an important immune factor in disease model evaluation. In this study, a 465 bp of the full-length IL-2 cDNA encoding sequence was cloned from the RNA of tree shrew spleen lymphocytes, which were then cultivated and stimulated with ConA (concanavalin). Clustal W 2.0 was used to compare and analyze the sequence and molecular characteristics, and establish the similarity of the overall structure of IL-2 between tree shrews and other mammals. The homology of the IL-2 nucleotide sequence between tree shrews and humans was 93%, and the amino acid homology was 80%. The phylogenetic tree results, derived through the Neighbour-Joining method using MEGA5.0, indicated a close genetic relationship between tree shrews, Homo sapiens, and Macaca mulatta. The three-dimensional structure analysis showed that the surface charges in most regions of tree shrew IL-2 were similar to between tree shrews and humans; however, the N-glycosylation sites and local structures were different, which may affect antibody binding. These results provide a fundamental basis for the future study of IL-2 monoclonal antibody in tree shrews, thereby improving their utility as a model.

Opposite effects of high and low doses of interleukin-2 on T cell-mediated hepatitis in mice (interleukin-2 on hepatitis)

PURPOSE

Concanavalin A (Con A)-induced hepatitis is an extensively used animal model of T cell-mediated acute hepatitis. A variety of cytokines, including interleukin 4 (IL-4), interferon gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α), have been shown to play important roles in Con A-induced liver injury. However, the role of IL-2, a critical cytokine in the development and function of T cells and a clinical therapeutics for virus infection and tumor, has not been carefully examined in this model.

METHODS

In this study, we investigated the function of IL-2 in Con A-induced hepatitis by using various strategies of rhIL-2 pretreatment. We treated mice with two rhIL-2 administration strategies: a single injection of high dose of rhIL-2 (IL-2(hi), 50 × 10(3) U/mouse) and four injections of low dose of rhIL-2 (IL-2(4lo), 5 × 10(3) U/mouse).

RESULTS

IL-2(hi) pretreatment ameliorated Con A-induced liver injury, while IL-2(4lo) aggravated Con A-induced liver injury. IL-2(hi) pretreatment reduced Con A-induced elevation of serum TNF-α while IL-2(4lo) pretreatment did not. Serum IL-4 and TNF-α were high 6 h after Con A injection in IL-2(4lo) mice, while it was undetectable in IL-2(hi) and non-pretreated mice. IL-2(hi) pretreatment reduced Con A-induced accumulation of T cells in liver while IL-2(4lo) pretreatment increased accumulation of NK cells.

CONCLUSION

Various strategies of rhIL-2 administration play different roles in Con A-induced hepatitis, suggesting the importance of IL-2 administrative regime in clinical liver diseases.

CD4+ T cell responses in hepatitis C virus infection

Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are relatively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type I profile, which promotes cellular effector mechanisms are thought to be more likely to experience viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells, especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in determining the outcome of acute and chronic HCV infection will be discussed in this review.

Characterization of colonic dendritic cells in normal and colitic mice

AIM: Recent studies demonstrating the direct involvement of dendritic cells (DC) in the activation of pathogenic T cells in animal models of inflammatory bowel disease identify DC as important antigen presenting cells in the colon. However, very little is known about the properties of colonic DC.

METHODS: Using immunohistochemistry, electron microscopy and flow cytometry we have characterized and compared colonic DC in the colon of healthy animals and interleukin-2-deficient (^IL2-/-) mice that develop colitis.

RESULTS: In the healthy colon, DC resided within the lamina propria and in close association with the basement membrane of colonic villi. Type 1 myeloid (CD11c⁺, CD11b⁺, B220-, CD8α-) DC made up the largest (40-45%) population and all DC expressed low levels of CD80, CD86, and CD40, and had high endocytic activity consistent with an immature phenotype. In colitic ^IL2-/- mice, colonic DC numbers increased four- to five-fold and were localized within the epithelial layer and within aggregates of T and B cells. They were also many more DC in mesenteric lymph nodes (MLN). The majority (>85%) of DC in the colon and MLN of ^IL2-/- mice were type 1 myeloid, and expressed high levels of MHC class II, CD80, CD86, CD40, DEC 205, and CCR5 molecules and were of low endocytic activity consistent with mature DC.

CONCLUSION: These findings demonstrate striking changes in the number, distribution and phenotype of DC in the inflamed colon. Their intimate association with lymphocytes in the colon and draining lymph nodes suggest that they may contribute directly to the ongoing inflammation in the colon.