Interleukin-1 receptor accessory protein blockade limits the development of atherosclerosis and reduces plaque inflammation.

AIMS: The interleukin-1 receptor accessory protein (IL1RAP) is a co-receptor required for signalling through the IL-1, IL-33, and IL-36 receptors. Using a novel anti-IL1RAP-blocking antibody, we investigated the role of IL1RAP in atherosclerosis. METHODS AND RESULTS: Single-cell RNA sequencing data from human atherosclerotic plaques revealed the expression of IL1RAP and several IL1RAP-related cytokines and receptors, including IL1B and IL33. Histological analysis showed the presence of IL1RAP in both the plaque and adventitia, and flow cytometry of murine atherosclerotic aortas revealed IL1RAP expression on plaque leucocytes, including neutrophils and macrophages. High-cholesterol diet fed apolipoprotein E-deficient (Apoe-/-) mice were treated with a novel non-depleting IL1RAP-blocking antibody or isotype control for the last 6 weeks of diet. IL1RAP blockade in mice resulted in a 20% reduction in subvalvular plaque size and limited the accumulation of neutrophils and monocytes/macrophages in plaques and of T cells in adventitia, compared with control mice. Indicative of reduced plaque inflammation, the expression of several genes related to leucocyte recruitment, including Cxcl1 and Cxcl2, was reduced in brachiocephalic arteries of anti-IL1RAP-treated mice, and the expression of these chemokines in human plaques was mainly restricted to CD68+ myeloid cells. Furthermore, in vitro studies demonstrated that IL-1, IL-33, and IL-36 induced CXCL1 release from both macrophages and fibroblasts, which could be mitigated by IL1RAP blockade. CONCLUSION: Limiting IL1RAP-dependent cytokine signalling pathways in atherosclerotic mice reduces plaque burden and plaque inflammation, potentially by limiting plaque chemokine production.

The Potential Role of IL1RAP on Tumor Microenvironment-Related Inflammatory Factors in Stomach Adenocarcinoma.

This study was performed to investigate the role of interleukin-1 receptor accessory protein (IL1RAP) in stomach carcinoma in vitro and in vivo, determine whether IL1RAP knockdown could regulate the development of stomach carcinoma, and elucidate the relationship between IL1RAP knockdown and inflammation by tumor microenvironment-related inflammatory factors in stomach carcinoma. We first used TCGA and GEPIA systems to predict the potential function of IL1RAP. Second, western blot and RT-PCR were used to analyze the expression, or mRNA level, of IL1RAP at different tissue or cell lines. Third, the occurrence and development of stomach carcinoma in vitro and in vivo were observed by using IL1RAP knockdown lentivirus. Finally, the inflammation of stomach carcinoma in vitro and in vivo was observed. Results show that in GEPIA and TCGA systems, IL1RAP expression in STAD tumor tissue was higher than normal, and high expression of IL1RAP in STAD patients had a worse prognostic outcome. Besides, GSEA shown IL1RAP was negative correlation of apopopsis, TLR4 and NF-κB signaling pathway. We also predicted that IL1RAP may related to IL-1 s, IL-33, and IL-36 s in STAD. The IL1RAP expression and mRNA level in tumor, or MGC803, cells were increased. Furthermore, IL1RAP knockdown by lentivirus could inhibit stomach carcinoma development in vitro and in vivo through weakening tumor cell proliferation, migration, invasion, therefore reducing tumor volume, weight, and biomarker levels, and increasing apoptotic level. Finally, we found IL1RAP knockdown could increase inflammation of tumor microenvironment-related inflammatory factors of stomach carcinoma, in vitro and in vivo. Our study demonstrates that IL1RAP is possibly able to regulate inflammation and apoptosis in stomach carcinoma. Furthermore, TLR4, NF-κB, IL-1 s, IL-33, and IL-36 s maybe the downstream target factor of IL1RAP in inflammation. These results may provide a new strategy for stomach carcinoma development by regulating inflammation.

Distinct Gene Expression Signatures Characterize Strong Clinical Responders Versus Nonresponders to Canakinumab in Children With Systemic Juvenile Idiopathic Arthritis.

OBJECTIVE: Canakinumab is a human anti-interleukin-1ß (anti-IL-1ß) blocking agent that effectively neutralizes IL-1ß-mediated signaling for treatment of systemic juvenile idiopathic arthritis (JIA). While many patients have dramatic clinical response to IL-1 blockade, approximately one-third fail to respond, but there are currently no validated clinical or immunologic predictors of response. We undertook this study to characterize distinct gene signatures for treatment response and nonresponse to canakinumab in systemic JIA patients. METHODS: We performed a secondary analysis of whole-blood gene expression microarrays using blood samples obtained from healthy controls and systemic JIA patients at baseline and on day 3 after canakinumab treatment (GEO accession no. GSE80060). Patients were considered strong clinical responders if they met the ACR90 response (exhibited ≥90% improvement in the American College of Rheumatology [ACR] JIA response criteria; nonresponders were those who met ACR30 [exhibiting ≤30% improvement in the ACR JIA response criteria]). A random-effects model with patient identity as the random variable was used for differential expression analysis. RESULTS: We identified a distinct gene expression signature in patients with a strong clinical response to canakinumab treatment as compared to nonresponders, mediated by up-regulation of neutrophil- and IL-1-associated genes and characterized by increasing divergence from control transcriptomes with increasing clinical response. We also identified a signature including up-regulated CD163 expression that was associated with canakinumab nonresponse. Intriguingly, canakinumab treatment induced either up- or down-regulation of type I interferon (IFN) genes, independent of clinical response. CONCLUSION: Here, we identify a gene signature in systemic JIA patients prior to receiving treatment that distinguishes strong responders to canakinumab from nonresponders. Further prospective studies are needed to assess the utility of these insights for treatment decisions in systemic JIA and to track the association of up-regulated type I IFN signatures with systemic JIA complications.

Associations between IL1RAP rs4624606, IL1RL1 rs1041973, IL-6 rs1800795, and HTRA1 rs11200638 gene polymorphisms and development of optic neuritis with or without multiple sclerosis.

BACKGROUND: Optic neuritis (ON) and multiple sclerosis (MS) are complex diseases with multifactorial pathogenesis. The role of genetic factors in the development of these diseases is hypothesized, and specific biochemical components involved in the pathogenesis of ON and MS are yet to be determined. The aim of our study was to determine the associations between IL1RAP rs4624606, IL1RL1 rs1041973, IL-6 rs1800795, and HTRA1 rs11200638 gene polymorphisms and development of ON with or without MS. MATERIALS AND METHODS: The study subjects included 80 ON patients and 146 healthy controls (HCs). Genotyping of IL1RAP rs4624606, IL1RL1 rs1041973, IL-6 rs1800795, and HTRA1 rs11200638 was performed using real-time polymerase chain reaction. RESULTS: A/C genotype of IL1RL1 rs1041973 was more frequent in ON patients than in HC subjects (p = 0.026). The IL1RL1 rs1041973 A/C genotype was associated with increased odds of ON development under the overdominant (p = 0.041) model. CONCLUSIONS: Our study showed that IL1RAP rs4624606, IL-6 rs1800795, and HTRA1 rs11200638 are not associated with an increased risk of developing ON. However, the IL1RL1 rs1041973 A/C genotype might be associated with an increased risk of developing ON.

Associations of IL6 rs1800795, BLK rs13277113, TIMP3 rs9621532, IL1RL1 rs1041973 and IL1RAP rs4624606 single gene polymorphisms with laryngeal squamous cell carcinoma.

OBJECTIVE: Survival rate of laryngeal squamous cell carcinoma (LSCC) patients is not improving. To understand more complete biology of LSCC, studies focused on identification of new specific and prognostic markers are performed. The aim of current study was to evaluate the impact of five different single nucleotide polymorphisms (SNP) (IL6 rs1800795, BLK rs13277113, TIMP3 rs9621532, IL1RL1 rs1041973 and IL1RAP rs4624606) on LSCC development. MATERIAL AND METHODS: A total of 891 subjects (353 histologically verified LSCC patients and 538 healthy controls) were involved in this study. The genotyping was carried out using the real-time-PCR. RESULTS: Statistical analysis revealed statistically significant associations between TIMP3 rs96215332 variants and LSCC in the codominant (OR = 0.600; 95% CI: 0.390-0.922; p = 0.020), overdominant (OR = 0.599; 95% CI: 0.390-0.922; p = 0.020) and additive (OR = 0.675; 95% CI: 0.459-0.991; p = 0.045) models. Also, significant variants of IL1RAP rs4624606 were determined in the codominant (OR = 1.372; 95% CI: 1.031-1.827; p = 0.030), overdominant (OR = 1.353; 95% CI: 1.018-1.798; p = 0.037) and additive (OR = 1.337; 95% CI: 1.038-1.724; p = 0.025) models. CONCLUSION: Results of the current study indicate significant associations between TIMP3 rs9621532 and IL1RAP rs4624606 gene polymorphisms and LSCC development.

Biallelic variants/mutations of IL1RAP in patients with steroid-sensitive nephrotic syndrome.

Nephrotic syndrome (NS) is a renal disease characterized by severe proteinuria and hypoproteinemia. Although several single-gene mutations have been associated with steroid-resistant NS, causative genes for steroid-sensitive NS (SSNS) have not been clarified. While seeking to identify causative genes associated with SSNS by whole-exome sequencing, we found compound heterozygous variants/mutations (c.524T>C; p.I175T and c.662G>A; p.R221H) of the interleukin-1 receptor accessory protein (IL1RAP) gene in two siblings with SSNS. The siblings' parents are healthy, and each parent carries a different heterozygous IL1RAP variant/mutation. Since IL1RAP is a critical subunit of the functional interleukin-1 receptor (IL-1R), we investigated the effect of these variants on IL-1R subunit function. When stimulated with IL-1ß, peripheral blood mononuclear cells from the siblings with SSNS produced markedly lower levels of cytokines compared with cells from healthy family members. Moreover, IL-1R with a variant IL1RAP subunit, reconstituted on a hematopoietic cell line, had impaired binding ability and low reactivity to IL-1ß. Thus, the amino acid substitutions in IL1RAP found in these NS patients are dysfunctional variants/mutations. Furthermore, in the kidney of Il1rap-/- mice, the number of myeloid-derived suppressor cells, which require IL-1ß for their differentiation, was markedly reduced although these mice did not show significantly increased proteinuria in acute nephrotic injury with lipopolysaccharide treatment. Together, these results identify two IL1RAP variants/mutations in humans for the first time and suggest that IL1RAP might be a causative gene for familial NS.

SRSF10-mediated IL1RAP alternative splicing regulates cervical cancer oncogenesis via mIL1RAP-NF-κB-CD47 axis.

High-risk human papillomavirus oncoproteins E6 and E7 are the major etiological factors of cervical cancer but are insufficient for malignant transformation of cervical cancer. Dysregulated alternative splicing, mainly ascribed to aberrant splicing factor levels and activities, contributes to most cancer hallmarks. However, do E6 and E7 regulate the expression of splicing factors? Does alternative splicing acts as an "accomplice" of E6E7 to promote cervical cancer progression? Here, we identified that the splicing factor SRSF10, which promotes tumorigenesis of cervix, was upregulated by E6E7 via E2F1 transcriptional activation. SRSF10 modulates the alternate terminator of interleukin-1 receptor accessory protein exon 13 to increase production of the membrane form of interleukin-1 receptor accessory protein. SRSF10-mediated mIL1RAP upregulates the expression of the "don't eat me" signal CD47 to inhibit macrophage phagocytosis by promoting nuclear factor-κB activation, which is pivotal in inflammatory, immune, and tumorigenesis processes. Altogether, these data reveal a close relationship among HPV infection, alternative splicing and tumor immune evasion, and also suggests that the SRSF10-mIL1RAP-CD47 axis could be an attractive therapeutic target for the treatment of cervical cancer.

microRNA-4331 Promotes Transmissible Gastroenteritis Virus (TGEV)-induced Mitochondrial Damage Via Targeting RB1, Upregulating Interleukin-1 Receptor Accessory Protein (IL1RAP), and Activating p38 MAPK Pathway In Vitro.

Transmissible gastroenteritis virus (TGEV), a member of the coronaviridae family, could cause fatal diarrhea of piglets and result in numerous economic losses. Previous studies demonstrated that TGEV infection could lead to mitochondrial damage and upregulate miR-4331 level. So miR-4331 may play an important regulatory role in the control of mitochondrial function. To explore the potential role of miR-4331 in mitochondrial damage, we adopted a strategy consisting of quantitative proteomic analysis of porcine kidney (PK-15) cells in response to miR-4331 and TGEV infection. Eventually, 69 differentially expressed proteins were gained. The target of miR-4331 was identified. The effects of miR-4331 and its target RB1 on mitochondrial Ca2+ level, mitochondrial membrane potential (MMP), interleukin-1 receptor accessory protein (IL1RAP), p38 MAPK signaling pathway were investigated. The results showed that miR-4331 elevated mitochondrial Ca2+ level, reduced MMP, targets Retinoblastoma 1 (RB1), upregulated IL1RAP, and induced activation of p38 MAPK pathway during TGEV infection. RB1 was identified as the direct targets of miR-4331 and downregulated IL1RAP, suppressed the activation of p38 MPAK, and attenuated TGEV-induced mitochondrial damage. In addition, IL1RAP played a positive role in activating p38 MAPK signaling and negative role in TGEV-induced mitochondrial damage. The data indicate that miR-4331 aggravates TGEV-induced mitochondrial damage by repressing expression of RB1, promoting IL1RAP, and activating p38 MAPK pathway.

Research of differential expression of sIL1RAP in low-grade gliomas between children and adults.

Glioma is the most common intracranial malignant tumor. Low-grade gliomas (LGG) occupy almost 80% in all of the gliomas. The prognosis of LGG in children is much better than in adult, however, the molecular mechanism is still unclear. In our investigation, it was first found that the level of soluble IL1RAP (sIL1RAP) was significantly higher in the LGG from children than that from adult. We also revealed that sIL1RAP could induce the apoptosis of U251. In cells with overexpression of sIL-1RAP, the cell proliferation promoted by IL-1 was significantly inhibited. These decreased tumor growth ability and better prognosis of low-grade gliomas in children patients than that in adult patients. The expression level of sIL1RAP may become one of the potential indexes for determining the prognosis of low-grade gliomas.

Single-cell molecular analysis defines therapy response and immunophenotype of stem cell subpopulations in CML.

Understanding leukemia heterogeneity is critical for the development of curative treatments as the failure to eliminate therapy-persistent leukemic stem cells (LSCs) may result in disease relapse. Here we have combined high-throughput immunophenotypic screens with large-scale single-cell gene expression analysis to define the heterogeneity within the LSC population in chronic phase chronic myeloid leukemia (CML) patients at diagnosis and following conventional tyrosine kinase inhibitor (TKI) treatment. Our results reveal substantial heterogeneity within the putative LSC population in CML at diagnosis and demonstrate differences in response to subsequent TKI treatment between distinct subpopulations. Importantly, LSC subpopulations with myeloid and proliferative molecular signatures are proportionally reduced at a higher extent in response to TKI therapy compared with subfractions displaying primitive and quiescent signatures. Additionally, cell surface expression of the CML stem cell markers CD25, CD26, and IL1RAP is high in all subpopulations at diagnosis but downregulated and unevenly distributed across subpopulations in response to TKI treatment. The most TKI-insensitive cells of the LSC compartment can be captured within the CD45RA- fraction and further defined as positive for CD26 in combination with an aberrant lack of cKIT expression. Together, our results expose a considerable heterogeneity of the CML stem cell population and propose a Lin-CD34+CD38-/lowCD45RA-cKIT-CD26+ population as a potential therapeutic target for improved therapy response.

Interleukin (IL)-1 in rat parturition: IL-1 receptors 1 and 2 and accessory proteins abundance in pregnant rat uterus at term - regulation by progesterone.

The role of interleukin-1 (IL-1), a pro-inflammatory cytokine, in parturition is typically noted by changes in its concentrations. Studying the expression of its receptor family, IL-1 receptor (IL-1R) 1, IL-1R2, IL-1R accessory protein (IL-1RAcP), and its predominantly brain isoform, IL-1RAcPb, during late gestation in the uterus in the Long-Evans rat is another. We assessed changes in their mRNA and protein relative abundance in the uterus and compared IL-1RAcP and IL-1RAcPb mRNA abundance in uterus, cervix, ovaries, placenta, and whole blood of Long-Evans rats during late gestation or in RU486 and progesterone-treated dams using quantitative real-time PCR and western immunoblotting. IL-1R1, IL-1RAcP, and IL-1RAcPb mRNA abundance significantly increased in the uterus at delivery whereas IL-1R2 mRNA abundance significantly decreased. IL-1R1 protein increased at term and IL-1R2 protein decreased at term compared to nonpregnant uteri. IL1-RAcPb mRNA abundance was less than IL-1RAcP, but in the lower uterine segment it was the highest of all tissues examined. RU486 stimulated preterm delivery and an increase in IL-1R1 mRNA abundance whereas progesterone administration extended pregnancy and suppressed the increase in IL-1R1. These data suggest that changes in uterine sensitivity to IL-1 occur during late gestation and suggest another level of regulation for the control of delivery. The roles for IL-1RAcP and IL-1RAcPb need to be determined, but may relate to different intracellular signaling pathways.

Clofazimine Biocrystal Accumulation in Macrophages Upregulates Interleukin 1 Receptor Antagonist Production To Induce a Systemic Anti-Inflammatory State.

Clofazimine (CFZ) is a poorly soluble antibiotic and anti-inflammatory drug indicated for the treatment of leprosy. In spite of its therapeutic value, CFZ therapy is accompanied by the formation of drug biocrystals that accumulate within resident tissue macrophages, without obvious toxicological manifestations. Therefore, to specifically elucidate the off-target consequences of drug bioaccumulation in macrophages, we compared the level of inflammasome activation in CFZ-accumulating organs (spleen, liver and lung) in mice after 2 and 8 weeks of CFZ treatment when the drug exists in soluble and insoluble (biocrystalline) forms, respectively. Surprisingly, the results showed a drastic reduction in caspase 1 and interleukin-1ß (IL-1ß) cleavage in the livers of mice treated with CFZ for 8 weeks (8-week-CFZ-treated mice) compared to 2-week-CFZ-treated and control mice, which was accompanied by a 3-fold increase in hepatic IL-1 receptor antagonist (IL-1RA) production and a 21-fold increase in serum IL-1RA levels. In the lung and spleen, IL-1ß cleavage and tumor necrosis factor alpha expression were unaffected by soluble or biocrystal CFZ forms. Functionally, there was a drastic reduction of carrageenan- and lipopolysaccharide-induced inflammation in the footpads and lungs, respectively, of 8-week-CFZ-treated mice. This immunomodulatory activity of CFZ biocrystal accumulation was attributable to the upregulation of IL-1RA, since CFZ accumulation had minimal effect in IL-1RA knockout mice or 2-week-CFZ-treated mice. In conclusion, CFZ accumulation and biocrystal formation in resident tissue macrophages profoundly altered the host's immune system and prompted an IL-1RA-dependent, systemic anti-inflammatory response.

Blood soluble interleukin 1 receptor accessory protein levels are consistently low throughout the menstrual cycle of women with endometriosis.

BACKGROUND: A deficiency in the counter-regulatory mechanisms of interleukin 1 (IL1) may play a significant role in endometriosis pathogenesis and associated chronic inflammation. The aim of this study was to investigate peripheral blood levels of soluble IL1 receptor accessory protein (sIL1RAP), a potent natural inhibitor of IL1, in women with and without endometriosis. METHODS: Peripheral blood samples were collected from women with endometriosis (n = 47) consulting for infertility, pelvic pain or tubal ligation, in whom the disease was diagnosed at laparoscopy. Control healthy women (n = 27) were requesting tubal ligation or reanastomosis and had no visible evidence of endometriosis at laparoscopy. sIL1RAP levels were determined by ELISA, whereas estradiol (E2) and progesterone (P4) levels were determined by competitive immunoassays. RESULTS: sIL1RAP levels were significantly decreased in women with early endometriosis stages compared to controls (p < 0.05) and markedly during the proliferative phase of the menstrual cycle (p < 0.001). Actually, while sIL1RAP were significantly increased in the proliferative compared to the secretory phase in normal women (p < 0.0001) and peaked at the end of this phase, sIL1RAP remained consistently low and showed non-significant variations throughout the menstrual cycle in women with endometriosis. CONCLUSIONS: Lower circulating levels of sIL1RAP points to a significant impairment in the counter-regulatory mechanisms of IL1, which in view of the cytokine's potent inflammatory and growth-promoting properties may play a significant role in the pathophysiology of endometriosis.

The structural pathway of interleukin 1 (IL-1) initiated signaling reveals mechanisms of oncogenic mutations and SNPs in inflammation and cancer.

Interleukin-1 (IL-1) is a large cytokine family closely related to innate immunity and inflammation. IL-1 proteins are key players in signaling pathways such as apoptosis, TLR, MAPK, NLR and NF-κB. The IL-1 pathway is also associated with cancer, and chronic inflammation increases the risk of tumor development via oncogenic mutations. Here we illustrate that the structures of interfaces between proteins in this pathway bearing the mutations may reveal how. Proteins are frequently regulated via their interactions, which can turn them ON or OFF. We show that oncogenic mutations are significantly at or adjoining interface regions, and can abolish (or enhance) the protein-protein interaction, making the protein constitutively active (or inactive, if it is a repressor). We combine known structures of protein-protein complexes and those that we have predicted for the IL-1 pathway, and integrate them with literature information. In the reconstructed pathway there are 104 interactions between proteins whose three dimensional structures are experimentally identified; only 15 have experimentally-determined structures of the interacting complexes. By predicting the protein-protein complexes throughout the pathway via the PRISM algorithm, the structural coverage increases from 15% to 71%. In silico mutagenesis and comparison of the predicted binding energies reveal the mechanisms of how oncogenic and single nucleotide polymorphism (SNP) mutations can abrogate the interactions or increase the binding affinity of the mutant to the native partner. Computational mapping of mutations on the interface of the predicted complexes may constitute a powerful strategy to explain the mechanisms of activation/inhibition. It can also help explain how an oncogenic mutation or SNP works.

The interleukin-1ß system in the corpora lutea of pigs during early pregnancy and the estrous cycle.

Expression of mRNAs encoding interleukin-1ß (IL-1ß), IL-1ß receptor I (IL-1RI), IL-1 receptor accessory protein (IL-1RAcP) and IL-1 receptor antagonist (IL-1Ra), as well as synthesis of IL-1ß and IL-1RI proteins, were examined in the corpus luteum (CL) during critical stages of CL activity on days 10-16 of pregnancy and 2-16 of the estrous cycle. Luteal cells were cultured in vitro with IL-1ß, and the effect on release of steroid hormones was determined. Expression of the IL-1ß system in the CL changed significantly during pregnancy and the estrous cycle. IL-1ß, IL-1RI, and IL-1Ra mRNA levels were elevated on days 12-13, whereas IL-1RAcP mRNA was increased on days 15-16 of pregnancy. In cyclic CL, expression of IL-1ß, IL-1RI, and IL-1RAcP mRNAs was increased on days 12-13. IL-1ß and IL-1RI protein were highest in the CL on days 10-11 and 8-11 of pregnancy and the estrous cycle. Luteal cells harvested from gravid and cyclic CL produced IL-1ß in vitro. IL-1ß increased progesterone and estradiol-17ß (E2) release by luteal cells on days 10-16 and 10-11 of pregnancy, respectively and on days 2-11 of the estrous cycle. IL-1ß decreased the level of E2 produced by regressed CL (days 15-16). Expression of the IL-1ß system in CL and IL-1ß secretion from luteal cells changed depending on the status of the CL. These data show that IL-1ß may be involved in intraluteal, luteotrophic regulation of CL functions in gravid and cyclic pigs.

Overexpression of IL-1 receptor accessory protein in stem and progenitor cells and outcome correlation in AML and MDS.

Cellular and interpatient heterogeneity and the involvement of different stem and progenitor compartments in leukemogenesis are challenges for the identification of common pathways contributing to the initiation and maintenance of acute myeloid leukemia (AML). Here we used a strategy of parallel transcriptional analysis of phenotypic long-term hematopoietic stem cells (HSCs), short-term HSCs, and granulocyte-monocyte progenitors from individuals with high-risk (-7/7q-) AML and compared them with the corresponding cell populations from healthy controls. This analysis revealed dysregulated expression of 11 genes, including IL-1 receptor accessory protein (IL1RAP), in all leukemic stem and progenitor cell compartments. IL1RAP protein was found to be overexpressed on the surface of HSCs of AML patients, and marked cells with the -7/7q- anomaly. IL1RAP was also overexpressed on HSCs of patients with normal karyotype AML and high-risk myelodysplastic syndrome, suggesting a pervasive role in different disease subtypes. High IL1RAP expression was independently associated with poor overall survival in 3 independent cohorts of AML patients (P = 2.2 × 10(-7)). Knockdown of IL1RAP decreased clonogenicity and increased cell death of AML cells. Our study identified genes dysregulated in stem and progenitor cells in -7/7q- AML, and suggests that IL1RAP may be a promising therapeutic and prognostic target in AML and high-risk myelodysplastic syndrome.

Interleukin-1ß and interleukin-1 receptor accessory protein gene polymorphisms are associated with persistent hepatitis B virus infection.

BACKGROUND/AIMS: The reasons for persistent HBV infection are unknown, but they are probably related to host immune factors. IL-1ß plays significant roles in inflammation and immune defense via IL-1RAcP. We investigated whether genetic polymorphisms of IL-1ß and IL-1RAcP genes are associated with persistent HBV infection and the presence of HCC. METHODOLOGY: We enrolled a total of 292 patients with chronic HBV infection (111 with chronic hepatitis, 95 with liver cirrhosis and 86 with HCC) and 107 healthy individuals who recovered from HBV infection. We assessed 28 SNPs in IL- 1ß and IL-1RAcP genes by using Illumina's Sentrix array matrix chip. RESULTS: IL-1ß-2023 C allele, IL-1RAcP -8261 T allele and -8183 A allele were significantly associated with persistent HBV infection (OR=1.63, p=0.03, OR=0.64, p<0.01 and OR=0.20, p=0.01, respectively). IL- 1ß 289 C allele was marginally associated with an increased risk for the presence of HCC (OR=1.55, p=0.04). On the haplotype analysis, IL-1ß-2023C/-581C/2893C haplotype and IL-1RAcP -8261T/-8183A haplotype were associated with persistent HBV infection. There was no significant association between the haplotypes of IL-1ß/IL-1RAcP and the presence of HCC. CONCLUSIONS: The genetic polymorphisms of IL-1ß-2023 C allele, IL- 1RAcP -8261 T allele and -8183 A allele are probable host factors for persistent HBV infection.

Engagement of IL-1 receptor accessory protein (IL-1RAcP) with the monoclonal antibody AY19 provides co-activating signals and prolongs the CD2-induced proliferation of peripheral blood lymphocytes.

IL-1 receptor accessory protein (IL-1RAcP) is the second subunit required to form a functional receptor complex for IL-1α and ß, IL-1F6, IL-1F8, IL1-F9 and IL-33. While it does not directly interact with the cytokines, IL-1RAcP is necessary to mediate signal transduction. We previously reported a monoclonal antibody with an unknown specificity, termed AY19, that was capable to induce a significant increase in the size of CFU-GM colonies when added to cultures of human cord blood CD34(+) hematopoietic progenitors. Here we demonstrate that AY19 mAb recognizes IL1-RAcP. We show that this adaptor molecule is significantly present on peripheral blood monocytes and lymphocytes including CD4(+) and CD8(+) T lymphocytes, B and NK cells. Interestingly, its expression is found increased on CD127(low)CD4(+)CD25(high) T cells when compared to CD127(low)CD4(+)CD25(-) T cell subset, suggesting that the level of IL-1RAcP membrane expression could allow to distinguish within CD127(low)CD4(+) T lymphocytes the CD25(high) T regulatory subset from conventional CD25(-) T lymphocytes. Functional studies reveal that addition of AY19 mAb enhances the proliferation of peripheral blood mononuclear cells (PBMC) obtained with mitogenic concentrations of PMA. Interestingly, we found that although AY19 mAb does not increase the optimal PBMC proliferation induced by a mitogenic pair of anti-CD2 mAbs it prolongs their time of proliferation. Thus, these results indicate that the anti-IL-1RAcP mAb AY19 exhibits unique functional properties by triggering co-stimulatory signals in lymphocytes.

Crosstalk between c-Jun and TAp73alpha/beta contributes to the apoptosis-survival balance.

The p53-family member p73 plays a role in various cellular signaling pathways during development and growth control and it can have tumor suppressor properties. Several isoforms of p73 exist with considerable differences in their function. Whereas the functions of the N-terminal isoforms (TA and ΔNp73) and their opposing pro- and antiapoptotic roles have become evident, the functional differences of the distinct C-terminal splice forms of TAp73 have remained unclear. Here, we characterized the global genomic binding sites for TAp73α and TAp73ß by chromatin immunoprecipitation sequencing as well as the transcriptional responses by performing RNA sequencing. We identified a specific p73 consensus binding motif and found a strong enrichment of AP1 motifs in close proximity to binding sites for TAp73α. These AP1 motif-containing target genes are selectively upregulated by TAp73α, while their mRNA expression is repressed upon TAp73ß induction. We show that their expression is dependent on endogenous c-Jun and that recruitment of c-Jun to the respective AP1 sites was impaired upon TAp73ß expression, in part due to downregulation of c-Jun. Several of these AP1-site containing TAp73α-induced genes impinge on apoptosis induction, suggesting an underlying molecular mechanism for the observed functional differences between TAp73α and TAp73ß.