Low-dose lipopolysaccharide exposure during oocyte maturation disrupts early bovine embryonic development

Gram-negative bacteria release of lipopolysaccharide (LPS) endotoxin elicits robust immune responses capable of disrupting normal ovarian function contributing to female infertility. However, effects of subclinical or non-detectable infections on oocyte competence and subsequent embryo development remain to be fully elucidated. The aim of this study was to investigate the effects of exposing bovine oocytes to low LPS doses on oocyte and embryo competence. Bovine oocytes were collected from slaughterhouse-derived ovaries and matured with vehicle-control or increasing doses of LPS (0.01, 0.1, and 1 μg/mL) for 21 h. Oocytes (n = 252) were evaluated for nuclear maturation. A set of embryos from LPS-matured oocytes (n = 300) were cultured for 8 d to evaluate day 3 cleavage rates and day 8 blastocyst rates along with blastocyst cell counts. A subset of oocytes (n = 153) was fertilized and cultured for time-lapse image capture and analysis of embryo development. Results demonstrate no significant treatment differences among treatment groups in percent of oocytes at germinal vesicle (GV; P = 0.90), germinal vesicle breakdown (GVBD; P = 0.13), meiosis I (MI; P = 0.26), or metaphase II (MII; P = 0.44). Likewise, treatment differences were not observed in cleavage rates (P = 0.97), or blastocyst rates (P = 0.88) evaluated via traditional microscopy. Treatment with LPS did not affect total blastocyst cell count (P = 0.68), as indicated by trophectoderm (P = 0.83), and inner cell mass (P = 0.21) cell counts. Time-lapse embryo evaluation demonstrated no differences among control or LPS matured oocytes in number of zygotes that did not cleave after fertilization (P = 0.84), or those that cleaved but arrested at the 2-cell stage (P = 0.50), 4-cell (P = 0.76), prior to morula (P = 0.76). However, embryos derived from oocytes challenged with 0.1 μg/mL LPS tended to have reduced development to the morula stage compared with vehicle-treated controls (P = 0.06). Additionally, the percentage of blastocysts derived from oocytes matured in 0.01 μg/mL LPS tended to decrease compared to vehicle-treated controls (11.38 and 25.45 %, respectively; P = 0.09). Similarly, the proportion of oocytes that developed to the blastocyst stage was greater in vehicle-treated controls (25.45 %) compared with embryos derived from oocytes matured in 0.1 and 1 μg/mL (5.92 and 6.55 %, respectively; P = 0.03) LPS. These data suggest LPS-matured oocytes that subsequently underwent in vitro fertilization, experienced decreased competence to develop to the blastocyst stage.

Myeloid cell-derived creatine in the hypoxic niche promotes glioblastoma growth

Glioblastoma (GBM) is a malignancy dominated by the infiltration of tumor-associated myeloid cells (TAMCs). Examination of TAMC metabolic phenotypes in mouse models and patients with GBM identified the de novo creatine metabolic pathway as a hallmark of TAMCs. Multi-omics analyses revealed that TAMCs surround the hypoxic peri-necrotic regions of GBM and express the creatine metabolic enzyme glycine amidinotransferase (GATM). Conversely, GBM cells located within these same regions are uniquely specific in expressing the creatine transporter (SLC6A8). We hypothesized that TAMCs provide creatine to tumors, promoting GBM progression. Isotopic tracing demonstrated that TAMC-secreted creatine is taken up by tumor cells. Creatine supplementation protected tumors from hypoxia-induced stress, which was abrogated with genetic ablation or pharmacologic inhibition of SLC6A8. Lastly, inhibition of creatine transport using the clinically relevant compound, RGX-202-01, blunted tumor growth and enhanced radiation therapy in vivo. This work highlights that myeloid-to-tumor transfer of creatine promotes tumor growth in the hypoxic niche.

Advanced Age in Humans and Mouse Models of Glioblastoma Show Decreased Survival from Extratumoral Influence

PURPOSE

Glioblastoma (GBM) is the most common aggressive primary malignant brain tumor in adults with a median age of onset of 68 to 70 years old. Although advanced age is often associated with poorer GBM patient survival, the predominant source(s) of maladaptive aging effects remains to be established. Here, we studied intratumoral and extratumoral relationships between adult patients with GBM and mice with brain tumors across the lifespan.

EXPERIMENTAL DESIGN

Electronic health records at Northwestern Medicine and the NCI SEER databases were evaluated for GBM patient age and overall survival. The commercial Tempus and Caris databases, as well as The Cancer Genome Atlas were profiled for gene expression, DNA methylation, and mutational changes with varying GBM patient age. In addition, gene expression analysis was performed on the extratumoral brain of younger and older adult mice with or without a brain tumor. The survival of young and old wild-type or transgenic (INK-ATTAC) mice with a brain tumor was evaluated after treatment with or without senolytics and/or immunotherapy.

RESULTS

Human patients with GBM ≥65 years of age had a significantly decreased survival compared with their younger counterparts. While the intra-GBM molecular profiles were similar between younger and older patients with GBM, non-tumor brain tissue had a significantly different gene expression profile between young and old mice with a brain tumor and the eradication of senescent cells improved immunotherapy-dependent survival of old but not young mice.

CONCLUSIONS

This work suggests a potential benefit for combining senolytics with immunotherapy in older patients with GBM.

STING agonist-loaded, CD47/PD-L1-targeting nanoparticles potentiate antitumor immunity and radiotherapy for glioblastoma

As a key component of the standard of care for glioblastoma, radiotherapy induces several immune resistance mechanisms, such as upregulation of CD47 and PD-L1. Here, leveraging these radiotherapy-elicited processes, we generate a bridging-lipid nanoparticle (B-LNP) that engages tumor-associated myeloid cells (TAMCs) to glioblastoma cells via anti-CD47/PD-L1 dual ligation. We show that the engager B-LNPs block CD47 and PD-L1 and promote TAMC phagocytic activity. To enhance subsequent T cell recruitment and antitumor responses after tumor engulfment, the B-LNP was encapsulated with diABZI, a non-nucleotidyl agonist for stimulator of interferon genes. In vivo treatment with diABZI-loaded B-LNPs induced a transcriptomic and metabolic switch in TAMCs, turning these immunosuppressive cells into antitumor effectors, which induced T cell infiltration and activation in brain tumors. In preclinical murine models, B-LNP/diABZI administration synergized with radiotherapy to promote brain tumor regression and induce immunological memory against glioma. In summary, our study describes a nanotechnology-based approach that hijacks irradiation-triggered immune checkpoint molecules to boost potent and long-lasting antitumor immunity against glioblastoma.

Checkpoint kinase 1/2 inhibition potentiates anti-tumoral immune response and sensitizes gliomas to immune checkpoint blockade

Whereas the contribution of tumor microenvironment to the profound immune suppression of glioblastoma (GBM) is clear, tumor-cell intrinsic mechanisms that regulate resistance to CD8 T cell mediated killing are less understood. Kinases are potentially druggable targets that drive tumor progression and might influence immune response. Here, we perform an in vivo CRISPR screen to identify glioma intrinsic kinases that contribute to evasion of tumor cells from CD8 T cell recognition. The screen reveals checkpoint kinase 2 (Chek2) to be the most important kinase contributing to escape from CD8 T-cell recognition. Genetic depletion or pharmacological inhibition of Chek2 with blood-brain-barrier permeable drugs that are currently being evaluated in clinical trials, in combination with PD-1 or PD-L1 blockade, lead to survival benefit in multiple preclinical glioma models. Mechanistically, loss of Chek2 enhances antigen presentation, STING pathway activation and PD-L1 expression in mouse gliomas. Analysis of human GBMs demonstrates that Chek2 expression is inversely associated with antigen presentation and T-cell activation. Collectively, these results support Chek2 as a promising target for enhancement of response to immune checkpoint blockade therapy in GBM.

B-cells Drive Response to PD-1 Blockade in Glioblastoma Upon Neutralization of TGFβ-mediated Immunosuppression

Immunotherapy has revolutionized cancer treatment but has yet to be translated into brain tumors. Studies in other solid tumors suggest a central role of B-cell immunity in driving immune-checkpoint-blockade efficacy. Using single-cell and single-nuclei transcriptomics of human glioblastoma and melanoma brain metastasis, we found that tumor-associated B-cells have high expression of checkpoint molecules, known to block B-cell-receptor downstream effector function such as plasmablast differentiation and antigen-presentation. We also identified TGFβ-1/TGFβ receptor-2 interaction as a crucial modulator of B-cell suppression. Treatment of glioblastoma patients with pembrolizumab induced expression of B-cell checkpoint molecules and TGFβ-receptor-2. Abrogation of TGFβ using different conditional knockouts expanded germinal-center-like intratumoral B-cells, enhancing immune-checkpoint-blockade efficacy. Finally, blocking αVβ8 integrin (which controls the release of active TGFβ) and PD-1 significantly increased B-cell-dependent animal survival and immunological memory. Our study highlights the importance of intratumoral B-cell immunity and a remodeled approach to boost the effects of immunotherapy against brain tumors.

Abstract B36: Nano-engineering of immunosuppressive myeloid cells for immunostimulation in glioblastoma

As a hallmark of glioblastoma (GBM), the myeloid-rich tumor microenvironment is one of the major causes of GBM immunosuppression and therapy resistance. Therefore, tumor-associated myeloid cells (TAMCs) have been identified as a promising therapeutic target for remodeling the immunologically “cold” brain tumors and overcoming the therapy resistance of GBM. Emerging research findings have uncovered the interplay between TAMCs and radiotherapy, a key component of the standard of care for GBM. While radiotherapy is known to induce antitumor immune response, in which the functionality of the myeloid compartment, including phagocytosis of tumor and subsequent activation of effector T cells, plays a key role, irradiation also triggers immune resistance mechanisms, such as the overexpression of anti-phagocytic molecule CD47 in gliomas and immune checkpoint molecule PD-L1 in TAMCs. To tackle this, a bispecific-lipid nanoparticle (B-LNP) was designed to hijack the irradiation-induced upregulation of immunosuppressive molecules for harnessing TAMCs to elicit antitumor immune response. The B-LNP was surface functionalized with anti-CD47/PD-L1 ligands to enable a simultaneous targeting of TAMCs and glioma cells through dual ligation. The engineered B-LNP effectively bound to and blocked CD47 and PD-L1 molecules, and served as a bridge to engage TAMCs for enhanced phagocytosis of glioma cells when combined with radiotherapy. To promote the TAMC-mediated activation of adaptive antitumor immunity post-phagocytosis, diABZI, a synthetic non-nucleotidyl agonist for stimulator of interferon genes (STING), was physically encapsulated into B-LNP as a payload therapeutic. Our results indicate that B-LNP/diABZI complex enabled a TAMC-specific STING activation in preclinical murine glioma model CT-2A, which transformed the immunosuppressive TAMCs into tumor-eradicating cells in the glioma microenvironment, as evidenced by immune profiling, single-cell RNA sequencing analysis, and bulk metabolomics. As a result, the nano-engineered TAMCs dramatically promoted tumor infiltration and anti-glioma activity of T cells, which improved the therapeutic outcome of radiotherapy, eradicating tumors from about 70% of the glioma-bearing mice, and generated a long-lasting immunological memory against gliomas. The translational potential of our nano-engineering approach was further validated using a glioma model that recapitulates the genetic, histological, and immunological features of human GBM, and using the clinical tumor specimens of GBM patients. In conclusion, our work demonstrates a nanotechnology-mediated immunomodulatory approach that targets and modulates the myeloid-rich GBM microenvironment as a combinatorial treatment for improving the existing standard of care for GBM.

Citation Format: Peng Zhang, Aida Rashidi, Junfei Zhao, Brandyn Castro, Abby Ellingwood, Yu Han, Aurora Lopez-Rosas, Markella Zannikou, Crismita Dmello, Rebecca Levine, Ting Xiao, Alex Cordero, Adam M Sonabend, Irina V Balyasnikova, Catalina Lee-Chang, Jason Miska, Maciej S Lesniak. Nano-engineering of immunosuppressive myeloid cells for immunostimulation in glioblastoma [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy; 2022 Oct 21-24; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2022;10(12 Suppl):Abstract nr B36.

EXTH-52. HARNESSING A B CELL THERAPY TO PROMOTE ANTI-GLIOBLASTOMA HUMORAL RESPONSE

Glioblastoma (GBM) continues to retain its dismal prognosis despite numerous new therapeutic modalities to target various aspects of the tumor. There is a need to identify new, and even personalized, targetable GBM specific antigens. Our B-cell-based vaccine (BVax) is generated by isolating immune experienced B cells, identified by 4-1BBL, from murine secondary lymphoid organs or patient blood. We have shown this subset of B cells to have anti-tumoral potential in GBM. These cells are strengthened with BAFF, CD40, and IFNg stimulation to form BVax and then activated in vitro to form plasmablasts. Immunoprecipitation-mass spectrometry is performed using BVax-derived antibodies and tumor lysate from the paired patient specimen. We have identified unique antigens bound by BVax-derived antibodies. Given the significant therapeutic benefit we have seen using BVax-derived antibodies in preclinical murine models, we hypothesize that targeting these unique antigens would have significant therapeutic benefit in GBM patients. We focused on antigens that showed a survival benefit with lower expression using CGGA database analysis. We then confirm the presence and prevalence of the antigens within tumor cells in the patient’s tissue using immunohistochemistry, identifying some antigens in up to 15% of tumor cells. Using our brain tumor bank repository, we screened other GBM patient’s tissue for the presence of these markers to determine the broader applicability of targeting each antigen. We have identified proteins key in extracellular matrix formation which promote tumor growth and progression in cancer, including the ability to induce epithelial-mesenchymal transition. Simultaneously we have developed a computational algorithm to predict which antigens BVax-derived antibodies will bind using single cell RNA sequencing data from GBM patient-derived tumor and BVax, which may have broader applicability to a larger number of patients. Both techniques serve as exciting platforms to identify new therapeutic targets in GBM.

CTNI-37. REPEATED OPENING OF THE BLOOD-BRAIN BARRIER WITH THE SKULL-IMPLANTABLE SONOCLOUD-9 (SC9) DEVICE: PHASE 1 TRIAL OF NAB-PACLITAXEL AND SC9 IN RECURRENT GLIOBLASTOMA

BACKGROUND

The blood-brain barrier (BBB) is a major impediment to pharmacological treatment of gliomas. Low-intensity pulsed ultrasound with concomitant administration of intravenous microbubbles (LIPU/MB), temporarily opens the BBB. Here we investigate the pharmacokinetics and safety of this approach of repeated delivery of albumin-bound paclitaxel (Abraxane®, ABX) to the peri-tumoral brain. To perform LIPU/MB-based BBB opening prior to ABX infusions, we used a novel 6 x 6 cm device with 9 ultrasound emitters (SC9) that is implanted in a skull window after tumor resection.

METHODS

A Phase 1 dose-escalation trial using Bayesian adaptive design was conducted (NCT04528680). Patients with recurrent operable glioblastoma, a WHO PS ≤ 2 and adequate bone marrow and organ function were eligible. After tumor resection and implantation of SC9, repeated cycles of BBB opening by LIPU/MB immediately followed by ABX, was performed every 3 weeks. Intraoperative LIPU/MB and low dose ABX was given prior to tumor resection allowed for investigation tissue concentrations and pharmacokinetics.

RESULTS

Seventeen patients have been treated at six escalating ABX dose levels (40-260 mg/m2). At dose of 260 mg/m2, a grade 3 reversible taxane-associated dose limiting encephalopathy was observed in one patient. The patient continued treatment at a lower dose in subsequent cycles. A second patient exhibited encephalopathy on cycle 2. One patient developed grade 2 cumulative peripheral neuropathy. Intraoperative pharmacokinetic studies showed that ABX tissue concentrations in non-enhancing peri-tumoral brain were increased 3.7-fold after LIPU/MB. sc-RNA-sequencing showed transcriptional dysregulation of membrane transporters, pathways related to trans-cytosis as well as cell-cell and cell-matrix adhesion.

CONCLUSIONS

The LIPU/MB using skull-implantable ultrasound enhances the penetration of ABX in large regions of the brain. The procedure can be performed repeatedly and safely. LIPU-based BBB opening leads to transcriptional alterations in brain endothelium. Funding: NIH/NCI 1R01CA245969-01A1, CarThera (SC9 devices), BMS/Celgene (Abraxane®).

DDEL-13. ULTRASOUND-ENHANCED DELIVERY OF LIPOSOMAL DOXORUBICIN ACROSS THE BLOOD BRAIN BARRIER INDUCES AN IFN-GPHENOTYPE IN MICROGLIA, MACROPHAGES, AND T CELLS AND IMPROVES RESPONSE TO PD-1 BLOCKADE IN GLIOMAS

INTRODUCTION

Given the limited drug penetration across the blood-brain barrier (BBB), the therapeutic potential of new and existing therapies has not been fully exploited for the benefit of glioblastoma (GBM) patients.

METHODS

Here we employed a novel drug delivery technology based on low-intensity pulsed ultrasound combined with intravenous microbubbles (LIPU/MB) that temporarily opens the BBB to deliver liposomal doxorubicin (DOX) and anti-PD-1 therapy (aPD-1) in mouse glioma models and 3 recurrent GBM patients. Immunological variables were evaluated in tumor and immune cells as well as efficacy in glioma-bearing mice treated with DOX delivered by LIPU. These included measurement of HLA ABC and HLA DR protein expression by tumor cells, microglia, and macrophages and IFN-g production by glioma-associated microglia and macrophages in mouse and human tumors. We also assessed efficacy of LIPU/MB enhanced combination therapy in glioma-bearing mice.

RESULTS

Upregulation of HLA ABC and HLA DR was observed in GBM cell lines at low concentrations of DOX. Tumor cells from GBM patients treated with DOX, aPD-1 and LIPU/MB showed increased expression of HLA ABC and HLA DR compared to paired pretreatment samples. In both mice and humans, LIPU/MB liposomal DOX increased absolute brain drug concentrations and elicited a specific IFN-g phenotype and MHC I expression in glioma-associated microglia and macrophages in mice and humans. Furthermore, LIPU/MB-mediated BBB opening increased brain concentrations of aPD-1 in mice and in peritumoral regions of GBM patients. Combined treatment with liposomal DOX and aPD-1 delivered with LIPU/MB resulted in long-term survival of glioma-bearing mice that relied on the activity of CD8+ T cells for its efficacy.

CONCLUSIONS

Overall, this translational study demonstrates the utility of LIPU/MB to stimulate intracranial immune responses in the context of treatment with DOX and aPD-1 for gliomas.

TMET-14. TUMOR-ASSOCIATED MYELOID CELL-DERIVED CREATINE PROMOTES GLIOBLASTOMA GROWTH IN HYPOXIC NICHES AND PSEUDOPALISADING TUMOR REGIONS

Glioblastoma (GBM) consists of a unique tumor microenvironment (TME) dominated by infiltrating tumor-associated myeloid cells (TAMCs). TAMCs are central to tumor growth and understanding how they support tumor progression is critical to identifying new therapeutic modalities. Examination of the metabolic and genetic phenotypes of TAMCs revealed that the de-novo creatine phenotype is central to their identity. Immunohistochemistry and multiplex fluorescence in GBM patient-derived tissue showed TAMC infiltration localizing to hypoxic pseudopalisading regions. Furthermore, single-cell RNAseq analysis of human and mouse models of GBM identified that the transporter of creatine, Slc6a8, is located on tumor cells within these regions. Spatial transcriptomics confirmed this transporter-synthesis gene compartmentalization is specific to hypoxic pseudopalisading regions, and further elucidated a radial glial cell gene signature for tumor cells expressing Slc6a8. Murine models recapitulated the TAMC de-novo creatine metabolic phenotype both ex-vivo and in-vitro. Metabolomics showed that TAMC-derived creatine can transfer to tumor cells in-vitro and is enhanced under hypoxic conditions. β-guanidinopropionic acid (β-GPA) is a creatine analog proposed to block Slc6a8 function and effectively blocked TAMC-derived creatine transfer to tumor cells in-vitro. Furthermore, β-GPA inhibited both the viability and size of spheres for tumor cells grown in stem-cell conditions. Lastly, inhibition of creatine transport using clinically relevant inhibitors enhanced survival following tumor implantation in murine models. This work highlights the key role of creatine in the pseudopalisading and hypoxic niche in GBM, offering evidence for a potential benefit in targeting this axis for GBM therapy regimens.

TMIC-42. LEVERAGING B CELL IMMUNITY TO PROMOTE IMMUNOTHERAPY IN GLIOBLASTOMA

Immunotherapy has revolutionized cancer treatment but has yet to be translated into brain tumors. Studies in melanoma and sarcoma, amongst other models, have revealed the accumulation of germinal-center-like B cells as a key survival predictor post-PD1 blockade. We seek to leverage B cell immunity to enhance immunotherapy effectiveness in glioblastoma (GBM). In human GBM and murine glioma models, we found that B cells in the tumor microenvironment (TME) are activated, but the expression of co-inhibitory molecules such as CD32 and CD72 blocks downstream effector function. Transcriptomic analysis showed high expression of inhibitory TGFβ receptors on B cells and high levels of TGFβ1 cytokine in the TME. We showed direct inhibition of B cell function through TGFβ signaling that could be prevented with TGFβ receptor blockade. Spatial multiplex immunofluorescence analysis of the TME revealed that tumor and myeloid cells express high levels of TGFβ and are also near B cells, allowing for TGFβ-mediated B cell inhibition. Blocking the TGFβ pathway via transgenic mice with TGFβ receptor knockout on B cells or TGFβ cytokine knockouts in myeloid cells, or generation of a CT2A tumor line with TGFβ cytokine knockdown, all demonstrated a survival benefit and more germinal-center-like B cells. There was also increased T cell proliferation and anti-tumor cytotoxicity. Finally, inhibiting αVβ8 integrin, a required factor that releases active TGFβ, is a translatable approach that also increased B cell proliferation and animal survival. Dual treatment with αVβ8+PD1 blockade showed the most potent survival as well as immunological memory against tumor re-challenge. Analysis of the B and T cell compartments after dual treatment showed synergy, with robust cellular proliferation and functional differentiation of plasmablasts and effector T cells. Collectively, our study highlights the importance of B cells in the TME and a remodeled approach to boost the effects of immunotherapy against GBM.

Translocon-associated protein subunit SSR3 determines and predicts susceptibility to paclitaxel in breast cancer and glioblastoma

PURPOSE

Paclitaxel (PTX) is one the most potent and commonly used chemotherapies for breast and pancreatic cancer. Several ongoing clinical trials are investigating means of enhancing delivery of PTX across the blood-brain barrier for glioblastomas (GBMs). Despite the widespread use of PTX for breast cancer, and the initiative to repurpose this drug for gliomas, there are no predictive biomarkers to inform which patients will likely benefit from this therapy.

EXPERIMENTAL DESIGN

To identify predictive biomarkers for susceptibility to PTX, we performed a genome-wide CRISPR knock-out (KO) screen using human glioma cells. The genes whose KO was most enriched in the CRISPR screen underwent further selection based on their correlation with survival in the breast cancer patient cohorts treated with PTX and not in patients treated with other chemotherapies, a finding that was validated on a second independent patient cohort using progression-free survival.

RESULTS

Combination of CRISPR screen results with outcomes from taxane-treated breast cancer patients led to the discovery of endoplasmic reticulum (ER) protein SSR3 as a putative predictive biomarker for PTX. SSR3 protein levels showed positive correlation with susceptibility to PTX in breast cancer cells, glioma cells and in multiple intracranial glioma xenografts models. Knockout of SSR3 turned the cells resistant to PTX while its overexpression sensitized the cells to PTX. Mechanistically, SSR3 confers susceptibility to PTX through regulation of phosphorylation of ER stress sensor IRE1α.

CONCLUSION

Our hypothesis generating study showed SSR3 as a putative biomarker for susceptibility to PTX, warranting its prospective clinical validation.

Serum TSH as a predictor of malignancy in indeterminate thyroid nodules

INTRODUCTION

Thyroid nodules are lesions that are radiologically distinct from the thyroid parenchyma. Cervical ultrasound diagnoses 19-67% of nodules and is crucial in identifying those that lack cytological characterisation. Approximately 25% of biopsies reveal an indeterminate cytological result (Bethesda III), in which the risk of malignancy is variable (5-15%). The clinical importance of the diagnostic strategy used for thyroid nodules results from the need to exclude malignancy. The aim of this study was to evaluate the usefulness of serum thyroid-stimulating hormone (TSH) levels as a predictor of malignancy in cytologically indeterminate thyroid nodules.

METHODS

Our retrospective study included 40 patients with cytologically indeterminate thyroid nodules seen in our hospital between January 2013 and December 2017. Clinical parameters were reviewed, including age, gender, serum TSH levels, family history of thyroid carcinoma, radiation exposure and some sonographic features of the nodules. Statistical analysis was performed using SPSS. Statistical significance was defined as p<0.05.

RESULTS

Female gender was predominant (85%) and the mean (SD) age was 53.3 (15) years. Thyroid carcinoma was confirmed in 28% of patients. Median TSH levels were higher in patients with malignant (2.73µIU/ml) compared with benign (1.56µIU/ml) nodules (p<0.05). We demonstrated an increased risk of malignancy in patients with TSH levels of 2.68µIU/ml or above (p<0.05).

CONCLUSION

Higher serum TSH levels are associated with an increased risk of thyroid carcinoma in cytologically indeterminate nodules. TSH can become a fundamental diagnostic tool in stratifying the risk of malignancy and assist in diagnostic and therapeutic approaches to these nodules.

IMMU-29. B-CELL-BASED VACCINE PRODUCES GLIOBLASTOMA-REACTIVE ANTIBODIES THAT CONTRIBUTE TO TUMOR CLEARANCE

Glioblastomas (GBM) are characterized by a strong immunosuppressive environment, contributing to their poor prognosis and limited therapeutic response to immunotherapies. B-cells represent a unique opportunity to promote immunotherapy due to their potential to kill tumors by both cellular and humoral immunity. To generate our B-cell-based vaccine (BVax) platform, we activated 41BBL+ B cells from tumor bearing mice or GBM patient blood with BAFF, CD40, and IFNg. We have previously demonstrated that BVax potentiates radiation therapy, temozolomide and checkpoint blockade in murine models of GBM via enhancement of CD8+ T-cell based immunity. The aim of this current study is to evaluate the humoral effector functions of BVax. We examined the antibody (Ab) repertoire in vivo from serum of tumor-bearing B-cell knockout mice treated with BVax or by ex vivo stimulation of patient-derived BVax. Upon systemic administration, BVax infiltrates the tumor where it differentiates into plasmablasts. Murine BVax- and BNaive-derived serum immunoglobulin generated in vivo showed that the majority of murine BVax-derived Ab were IgG isotype, while BNaive mainly produced IgM isotype. Transfer of IgG from BVax treated mice directly into tumors of recipient animals significantly prolonged their survival, demonstrating anti-tumor cytotoxicity directly through humoral immunity. Patient-derived BVax activated ex vivo showed a plasmablast phenotype and the Ab repertoire supports the previous findings seen in our murine model. Our work suggests BVax-derived IgGs role in antibody-dependent cellular cytotoxicity and improved survival in murine models. This function, in addition to its role in cellular immunity against GBM, renders BVax a potentially effective alternative immunotherapeutic option for GBM patients.

EXTH-29. DUAL TGFB AND PD1 BLOCKADE PROMOTES GERMINAL-CENTER B-CELL IMMUNE RESPONSES AGAINST GLIOBLASTOMA

In contrast to other malignancies such as melanoma and sarcoma, Glioblastoma (GBM) remains difficult to treat with immunotherapies. Recent studies have shown that positive immunotherapeutic responses are mediated by the accumulation of germinal-center-like B cells which are predictive of survival in patients treated with neoadjuvant PD1 blockade. In contrast, GBM-associated B-cells are scarce and the establishment of germinal-center like cells have not been observed. This study seeks to identify how B-cells are driven towards their immunosuppressive phenotypes in GBM and how this prevents immunotherapeutic efficacy. Utilizing single-cell RNA sequencing (scRNA-seq) in a CT2A murine glioma model, TGFb receptors 1 and 3 were identified as the most highly expressed inhibitory receptors on GBM-associated B cells. Furthermore, using scRNA-seq, TGFb1 was identified as the most highly expressed immunosuppressive cytokine in the TME, which was produced principally by tumor-associated myeloid cells (TAMCs). Inhibiting the myeloid compartment using intracranial anti-Gr1 antibody in combination with PD1 blockade resulted in B-cells exhibiting greater proliferation and differentiation into memory B-cells in addition to germinal-center-like B-cells. Further demonstrating B-cell functional reprogramming, autologous T cells isolated from spleens exhibited greater proliferation and robust anti-tumor cytotoxicity when cocultured with tumor-associated B-cells from the dual treatment group. Finally, inhibiting a5b8 integrin, a key complex in releasing active TGFb, increased tumor-infiltrating proliferating B-cells and conferred a long-term survival benefit in the CT2A murine model. Our results demonstrate that the immunosuppressive TME of GBM is influenced by the vital interplay between B-cells and the TME through TGFb signaling. This study highlights the potential therapeutic benefits of targeting the TGFb signaling pathway in conjunction with the current standard of care for GBM.

TAMI-25. UPREGULATION OF CREATINE METABOLISM BY MYELOID CELLS RESULTS IN GLIOBLASTOMA PROGRESSION

Malignant brain tumors are uniquely immunosuppressive, with a predominant infiltration of immunosuppressive tumor-associated myeloid cells (TAMCs) and a deficit in T-cells unrivaled to any other tumor. This unique tumor microenvironment (TME) promotes resistance to both conventional and immune therapies for this disease. The underlying mechanisms by which TAMCs promote glioblastoma (GBM) progression are not fully understood. We found that TAMCs specifically upregulate de-novo creatine metabolism within GBM using unbiased genetic and metabolic screening. This metabolic phenotype was confirmed in human GBM patients by comparing peripheral versus tumor-infiltrating myeloid cells. Examination of de-novo creatine generation using Carbon13 arginine flux revealed that TAMCs, but not tumor-infiltrating CD8+ T-cells, can produce creatine. Furthermore, we demonstrate that TAMCs actively secrete de-novo generated creatine into cell cultures. Examination of the single-cell microenvironment of GBM revealed that malignant cells preferentially express the creatine transporter, indicating that TAMC-derived creatine is taken up by GBM. Notably, SLC6A8 is directly upregulated in the context of hypoxia and suggests that creatine uptake is a mechanism to promote survival under hypoxic stress. Indeed, exogenous creatine supplementation promoted both the migration and survival of multiple glioblastoma cell lines in-vitro. Utilizing an established inhibitor of creatine metabolism, β-Guanidinopropionic acid (β -GPA), we found that β -GPA blocks both the migration and survival of glioma cells under hypoxic stress. Lastly, β -GPA also inhibited creatine secretion by TAMCs, showing that creatine blockade can also influence TAMC metabolic phenotype. In the future, we will examine the importance of creatine metabolism on both immune suppression and tumor progression in-vivo. This work provides novel insights into the role of creatine metabolism in GBM and identifies a unique therapeutic avenue for this devastating disease.

BIOM-32. ENDOPLASMIC RETICULUM PROTEIN SSR3 DETERMINES AND PREDICTS RESPONSE TO PACLITAXEL IN BREAST CANCER AND GLIOBLASTOMA

Paclitaxel (PTX) is one the most potent and commonly used chemotherapies for breast and pancreatic cancer. Given the potency of this drug for glioblastomas (GBM) several ongoing clinical trials are investigating means of enhancing delivery of PTX across the blood-brain barrier for this disease. In spite of the efficacy of PTX, individual tumors exhibit variable susceptibility to this drug, with response rate in the range of 30%-60%. To identify predictive biomarkers for response to PTX, we performed a genome-wide CRISPR knock-out screen using human glioma cells. The most enriched genes in the CRISPR screen underwent further selection based on their correlation with survival in the breast cancer patient cohorts treated with PTX and not in patients treated with other chemotherapies, a finding that was validated on a second independent patient cohort. This led to the discovery of endoplasmic reticulum (ER) protein SSR3 as a putative predictive biomarker for PTX. SSR3 protein levels showed positive correlation with response to PTX in breast cancer cells, glioma cells, in multiple intracranial glioma xenografts and in GBM patient derived explant cultures. Knockout of SSR3 turned the cells resistant to PTX while its overexpression sensitized the cells to PTX. In gliomas, SSR3-mediated susceptibility to PTX relates to modulation of phosphorylation of ER stress sensor IRE1α. Thus, by using genome-wide screen combined with patient response data, we discovered a biomarker that demonstrates causal and correlative relationship with response to PTX in breast cancer and GBM. Prospective validation of this biomarker is warranted for its broad implementation for precision oncology.

IMMU-36. B CELL-VACCINE ELICITS LONG TERM IMMUNITY AGAINST GLIOBLASTOMA VIA ACTIVATION AND DIFFERENTIATION OF TUMOR-SPECIFIC CD8+ MEMORY T CELLS

While immunotherapy is used clinically to treat many cancers, its translation into brain tumors remains elusive. The importance of B cells in cancer immunity has become increasingly clear, and we previously developed a B cell-based cellular vaccine (BVax) against glioblastoma (GBM) by further activating 4-1BBL+ B cells with CD40 agonism and IFNγ. BVax were characterized as professional antigen-presenting cells (APCs) that promote CD8+ T cell migration and persistence in murine tumor-bearing brains. This study seeks to understand the mechanisms underlying BVax-induced CD8+ T cell fitness in the tumor microenvironment. Initial transcriptomic analysis highlighted that Bvax express high levels of IL15Rα, indicating their potential ability to trans-present IL15. Considering IL15 trans-presentation is fundamental in T-cell memory differentiation, we used BVax to induce T cell activation in the presence of exogenous IL15. BVax were better capable of activating antigen-specific CD8+ T cells and promoting a memory phenotype when compared to other professional APCs such as dendritic cells (DCs). T cell receptor (TCR) CDR3β sequencing showed that BVax expanded a number of TCR clones in-vitro that were found in brains of CT2A tumor-bearing mice in-vivo. These BVax-activated CD8+ T cells displayed a stronger antigen recall response and unique metabolic profile compared to DC-activated CD8+ T cells as shown by metabolomic analysis of tumor-infiltrating CD8+ T cells. When comparing the anti-tumor effects of CD8+ T cells activated by various APCs, BVax with exogenous IL15 promoted CD8+ T cells that displayed the most potent cytotoxicity against GBM cells in-vitro. Collectively, this study suggests that the IL15/IL15Rα axis and interactions with CD8+ T cell are key factors of BVax therapy in promoting a robust survival benefit and long-term immunologic memory against GBM in preclinical models. Additionally, the development of T cell therapies based on B cell licensing can be a promising future approach for glioblastoma therapy.

Current Immunotherapeutic Strategies for the Treatment of Glioblastoma

Glioblastoma (GBM) is a lethal primary brain tumor. Despite extensive effort in basic, translational, and clinical research, the treatment outcomes for patients with GBM are virtually unchanged over the past 15 years. GBM is one of the most immunologically "cold" tumors, in which cytotoxic T-cell infiltration is minimal, and myeloid infiltration predominates. This is due to the profound immunosuppressive nature of GBM, a tumor microenvironment that is metabolically challenging for immune cells, and the low mutational burden of GBMs. Together, these GBM characteristics contribute to the poor results obtained from immunotherapy. However, as indicated by an ongoing and expanding number of clinical trials, and despite the mostly disappointing results to date, immunotherapy remains a conceptually attractive approach for treating GBM. Checkpoint inhibitors, various vaccination strategies, and CAR T-cell therapy serve as some of the most investigated immunotherapeutic strategies. This review article aims to provide a general overview of the current state of glioblastoma immunotherapy. Information was compiled through a literature search conducted on PubMed and clinical trials between 1961 to 2021.

POS1376 UVEITIS IN 1449 PATIENTS WITH INFLAMMATORY BOWEL DISEASE. STUDY FROM A SINGLE UNIVERSITY CENTER

Background:

Inflammatory bowel disease (IBD), which includes Crohn’s disease (CD), and Ulcerative colitis (UC) are related to Spondyloarthritis (SpA). Ocular manifestations (OM) are well-stablished in axial SpA but not in IBD. It has been classically reported that whereas uveitis with axial SpA is predominantly anterior, unilateral, acute, and non-recurrent; in IBD it is bilateral, posterior, insidious, and chronic (1).

Objectives:

In a large unselected series of IBD, our aim was to assess a) epidemiology and clinical features of uveitis associated to IBD, b) to compare patients who developed uveitis and those who did not, and c) its relationship with biological treatment used in IBD.

Methods:

Study of all consecutive patients from a single University Hospital during the last 40 years with: a) IBD (CD and UC), and b) uveitis according to Standarization Uveitis Nomenclature (SUN) Working Group. Demographic features, clinical findings, occurrence of other extraintestinal manifestations and treatment were recorded.

Results:

We studied 1449 (714 women/735 men) patients with IBD, mean age of 55.2±15.9 years.

Uveitis was present in 23 (1.6 %) (38 eyes) of 1448 IBD patients. The most common pattern of uveitis was typically anterior (n=18; 78.3%), unilateral (n=19; 82.6%), acute (n=19; 82.6%), and non-recurrent (n=12; 52.2%).

The comparative study between patients with and without uveitis showed a significant predominance of women (Table 1) in patients with uveitis, as well as erythema nodosum, hidradenitis suppurativa and joint involvement.

Regarding IBD severity, in terms of surgical interventions, and conventional and biological immunosuppressive treatments, there were no significant differences.

Conclusion:

Although uveitis is more infrequent in IBD than in axial SpA, it is also anterior, unilateral, acute, and non-recurrent in contrast with published data from selected series. Patients with uveitis do not seem to represent more severe phenotype of IBD.

References:

[1]Lyons & Rosenbaum JT. Arch Ophthalmol 1997; 115:61-4.

Table 1.

General features of 1448 patients with IBD with and without uveitis.

Overall(n=1449)Uveitis(n=23)Non uveitis(n=1426)pMain general featuresAge, years, mean±SD55.2±15.949.1±14.655.2±15.90.8Sex, women/men, n, (% of women)714 / 735 (49.3)17 / 6 (73.9)697 / 729 (48.9)0.02*IBD duration, years, mean±SD13.2 ± 9.717.4 ± 10.213.1 ± 8.90.08IBD SeveritySurgical Interventions, n (%)289 (19.9)2 (8.7)284 (19.9)0.7Conventional Immunosuppressive drugs, n (%)878 (60.6)14 (60.9)863 (60.5)0.5Biological Therapy, n (%)384 (26.5)7 (30.4)378 (26.5))0.9TNFi monoclonal antibodies384 (26.5)7 (30.4)378 (26.5)0.9Ustekinumab27 (1.9)1 (4.3)27 (1.9)0.5Other23 (1.6)1 (4.3)22 (1.6)0.3Extraintestinal manifestationsCutaneous manifestations, n (%) (TOTAL)125 (8.6)9 (39.1)121 (8.7)0.1Erythema nodosum, n (%)26 (1.8)6 (26.1)24 (1.7)0.009*Pyoderma gangrenosum, n (%)13 (0.9)1 (4.3)13 (0.9)0.7Hidradenitis suppurativa, n (%)2 (0.1)1 (4.3)1 (0.1)0.0001*Joint involvement, n (%) (TOTAL)131 (9)10 (43.5)121 (8.5)0.0001*Axial pattern, n (%)65 (4.5)4 (17.4)58 (4.1)0.0001*Peripheral pattern, n (%)64 (4.4)4 (17.4)63 (4.4)0.9

Disclosure of Interests:

Lara Sanchez-Bilbao: None declared, María José García-García: None declared, David Martínez-López: None declared, Montserrat Rivero-Tirado: None declared, Beatriz Castro: None declared, Iñigo González-Mazón: None declared, Javier Crespo: None declared, Miguel A González-Gay Speakers bureau: AbbVie, Pfizer, Roche, Sanofi, Celgene and MSD., Grant/research support from: AbbVie, MSD, Jansen and Roche,, Ricardo Blanco Speakers bureau: AbbVie, Pfizer, Roche, Bristol-Myers, Janssen, Lilly and MSD., Grant/research support from: AbbVie, MSD and Roche

Polyamines drive myeloid cell survival by buffering intracellular pH to promote immunosuppression in glioblastoma

Glioblastoma is characterized by the robust infiltration of immunosuppressive tumor-associated myeloid cells (TAMCs). It is not fully understood how TAMCs survive in the acidic tumor microenvironment to cause immunosuppression in glioblastoma. Metabolic and RNA-seq analysis of TAMCs revealed that the arginine-ornithine-polyamine axis is up-regulated in glioblastoma TAMCs but not in tumor-infiltrating CD8+ T cells. Active de novo synthesis of highly basic polyamines within TAMCs efficiently buffered low intracellular pH to support the survival of these immunosuppressive cells in the harsh acidic environment of solid tumors. Administration of difluoromethylornithine (DFMO), a clinically approved inhibitor of polyamine generation, enhanced animal survival in immunocompetent mice by causing a tumor-specific reduction of polyamines and decreased intracellular pH in TAMCs. DFMO combination with immunotherapy or radiotherapy further enhanced animal survival. These findings indicate that polyamines are used by glioblastoma TAMCs to maintain normal intracellular pH and cell survival and thus promote immunosuppression during tumor evolution.

Coagulopathy as a Surrogate of Severity of Injury in Penetrating Brain Injury

Penetrating brain injury (PBI) is the most devastating type of traumatic brain injury. Development of coagulopathy in the acute setting of PBI, though common, remains of unclear significance as does its reversal. The aim of this study is to investigate the relationship between coagulopathy and clinical presentation, radiographical features, and outcome in civilian patients with PBI. Eighty-nine adult patients with PBI at a Level I trauma center in Chicago, Illinois who survived acute resuscitation and with available coagulation profile were analyzed. Coagulopathy was defined as international normalized ratio [INR] >1.3, platelet count <100,000 /μL, or partial thromboplastin time >37 sec. Median age (interquartile range; IQR) of our cohort was 27 (21-35) years, and 74 (83%) were male. The intent was assault in 74 cases (83%). The mechanism of PBI was gunshot wound in all patients. Forty patients (45%) were coagulopathic at presentation. In a multiple regression model, coagulopathy was associated with lower Glasgow Coma Scale (GCS)-Motor score (odds ratio [OR], 0.67; confidence interval [CI], 0.48-0.94; p = 0.02) and transfusion of blood products (OR, 3.91; CI, 1.2-12.5; p = 0.02). Effacement of basal cisterns was the only significant radiographical features associated with coagulopathy (OR, 3.34; CI, 1.08-10.37; p = 0.04). Mortality was found to be significantly more common in coagulopathic patients (73% vs. 25%; p < 0.001). However, in our limited sample, reversal of coagulopathy at 24 h was not associated with a statistically significant improvement in outcome. The triad of coagulopathy, low post-resuscitation GCS, and radiographical effacement of basal cisterns identify a particularly ominous phenotype of PBI. The role, and potential reversal of, coagulopathy in this group warrants further investigation.

Review of Philippine Health Laws and its Implication to HTA Institutionalization

Objective

To identify the implications of health legislations on the direction of health technology assessment (HTA) institutionalization in the Philippines.

Methods

We reviewed 15 health laws and extracted information using a preset data extraction tool. The collected data was then subjected to the KJ (Kawakita Jiro) method to group similar provisions, taking into account their respective implications to the HTA direction. Once grouped, a core concept was identified that captured the underlying provisions within the group. After which, the core concepts were tabulated and matched with the core components of HTA institutionalization to identify specific policy implication to HTA.

Results

Three major paradigms emerged that are considered important in the institutionalization of HTA. First, common among the health laws are the need for the provision or expansion of benefit packages through the Philippine Health Insurance Corporation. Aside from the benefit packages, the reviewed laws also require delivery of new health services that entail the use of specific health technologies. Lastly, as a consequence of the need for new health services, equity concerns became evident in relation to the identified health services specifically in terms of socioeconomic divide, geographical location and disease status.

Discussion and Conclusions

The three paradigms identified from the review of health laws indicate synergism and antagonism to the HTA-related policy content of the Philippines' UHC Law. Some identify the need for HTA before being funded by the government while others do not explicitly state this. Despite the health laws requiring expansion or creation of benefit packages and delivery of new health services, there is still a need to undergo HTA in order to ensure efficient use of resources. The presence of these laws should not be tantamount to exception of undergoing HTA process but rather should be taken as a guide for priority-setting of topics for assessment.

Key messages

In the process of institutionalizing HTA, existing legislations on health can help map out areas of priority for assessment. Many health policies preceded the signing of the Universal Health Care Law, thus it is important to review them to determine provisions that are synergistic or antagonistic to the content of UHC Law.

Impact of immune-mediated diseases in inflammatory bowel disease and implications in therapeutic approach

Inflammatory bowel diseases (IBD) belong to the group of immune-mediated diseases (IMIDs). The effect of associated IMIDs in the prognosis in IBD is nowadays unknown. To describe IMIDs associated to IBD patients and evaluate differences linked to the presence or absence of IMIDs. A unicentric retrospective descriptive study was designed. A cohort of 1,448 patients were categorized according to the presence of IMIDs. Clinical characteristics were obtained from IBD database. Univariate and multivariate analysis were performed. 385 patients were diagnosed with associated IMIDs while 1,063 had no associated IMIDs. A prevalence of 26.6% IMIDs associated to IBD was observed. Asthma, skin psoriasis and rheumatoid diseases were most commonly found. Factors associated to the presence of IMIDs were women (OR 1.48; 95 CI 1.17–1.87) and Crohn’s disease (OR 1.35; 95 CI 1.07–1.70). Patients with associated IMIDs required more immunomodulator (OR 1.61; 95 CI 1.27–2.43) and biological treatment (OR 1.81; 95 CI 1.47–2.43). More surgical risk was observed in multivariate analysis in those patients diagnosed with IMIDs prior to the onset of IBD (OR 3.71; 95% CI 2.1–6.56). We considered the presence of IMIDs a poor prognostic factor and suggest a closer monitoring of these patients.

Intraparotid mucous retention cyst in an infant: a rare case report

Mucocoeles can be defined as benign lesions that have resulted from extravasation or retention of saliva in the extraglandular spaces, and commonly affect the minor salivary glands. This case details a mucous retention cyst within the parotid gland of an infant, and its management.

AB0721 OCULAR INVOLVEMENT IN INFLAMMATORY BOWEL DISEASE. STUDY OF 1442 PATIENTS FROM A SINGLE UNIVERSITARY CENTER

Background:

Inflammatory bowel disease (IBD), which includes Crohn’s disease (CD), and Ulcerative colitis (UC) are related to Spondyloarthritis (SpA). Ocular manifestations (OM) are well-stablished in SpA but not in IBD. It has been classically reported that whereas uveitis with SpA is predominantly anterior, unilateral, sudden, and limited; in IBD it is bilateral, posterior, insidious, and chronic(Lyons & Rosenbaum JT. Arch Ophthalmol 1997; 115:61-4).

Objectives:

In a large unselected series of IBD, we study the OM and assess;a) epidemiological, clinical features,b) the relationship with extraintestinal manifestations.

Methods:

Study of all consecutive patients from a single University Hospital during the last 40 years with: a) IBD (CD and UC), andb) OM: uveitis and scleral pathology diagnosed by clinical features and slit-lamp.

Results:

OM were present in 42 (2.9%) (25 women/17 men) (84 eyes) of 1442 IBD patients; OM included the uveitis group (UG) (n=23; 1.6%) and the scleral pathology group (SG) (n=19, 1.32%) (TABLE).

The most common pattern in SG was episcleritis (n=16; 84.21%) and scleritis (n=3). In UG, uveitis was typically anterior (n=18; 78.3%), unilateral (n=19; 82.6%), sudden (n=19; 82.6%), and limited (n=12; 52.2%).

The comparative study between SG vs UG showed in UG a significant predominance of women and UC. Also, a non-significative higher frequency in Pyoderma gangrenosum, erythema nodosum and joint involvement was observed in UG.

After a mean follow-up of 15.2±9.97 years, extraintestinal manifestations were observed in 100% of patients, being articular forms (n=16; 38.10%) the most common type. In addition, joint/axial flare is more related to the presence of uveitis (p=0.038).

Conclusion:

Both uveitis and episcleritis are equally frequent OM in IBD. Although uveitis is more infrequent in IBD than in SpA, it is also anterior, unilateral, sudden and limited in contrast with published data from selected series.

References:

[1]Lyons & Rosenbaum JT. Arch Ophthalmol 1997; 115:61-4

TABLE.Uveitis(n= 23)Epi/scleritis(n=19)pDEMOGRAPHIC PARAMETERSSex, n (%)6 ♂ / 17 ♀11 ♂ / 8 ♀p= 0.04*Age at diagnosis (years) mean ± SD49.13±14.6447.63±12.48p= 0.415INTESTINAL AFFECTIONCD, n (%)12 (52.17)16 (84.21)p= 0.02*UC, n (%)11 (47,83)3 (15,74)p= 0.16EXTRAINTESTINAL AFFECTIONCutaneous manifestations•Erythema nodosum, n (%)6 (26.09)2 (10.53)p= 0.30•Pyoderma gangrenosum, n (%)1 (4.35)0 (0)p= 0.92•Psoriasis, n (%)1 (4.35)4 (21.01)p= 0.23Joint involvement10 (43.50)6 (31.60)p= 0.36•Psoriathic arthritis, n (%)1 (4.35)3 (15.80)p= 0.47•Enteropathic Spondyloarthritis, n (%)6 (26.09)3 (15.80)p= 0.66•Ankylosing Spondylitis, n (%)3 (13.04)0 (0)p= 0.28Digestive manifestations•NASH, n(%)4 (17.39)6 (31.58)p= 0.28

*p value < 0.05. SD:standard deviation;CD:Crohn’s disease; UC:ulcerative colitis; NASH:non-alcoholic steatohepatitis.

Disclosure of Interests:

Lara Sanchez-Bilbao Grant/research support from: Pfizer, David Martinez-Lopez: None declared, Iñigo González-Mazón: None declared, María José García-García: None declared, Montserrat Rivero-Tirado: None declared, Beatriz Castro: None declared, Javier Crespo: None declared, Miguel A González-Gay Grant/research support from: Pfizer, Abbvie, MSD, Speakers bureau: Pfizer, Abbvie, MSD, Ricardo Blanco Grant/research support from: AbbVie, MSD, and Roche, Speakers bureau: AbbVie, Pfizer, Roche, Bristol-Myers, Janssen, and MSD

Role of VEGFs in metabolic disorders

Obesity and metabolic disorders are important public health problems. In this review, the role of vasculature network and VEGF in the adipose tissue maintenance and supplementation is discussed. Angiogenesis is a key process implicated in regulation of tissues homeostasis. Dysregulation of new blood vessels formation may be crucial and contribute to the onset of several pathological conditions, including metabolic syndrome-associated disorders. Adipose tissue homeostasis is fine regulated by vascular network. Vessels support adipose structure. Vasculature modulates the balance between positive and negative regulator factors. In white adipose tissue, vascular endothelial growth factor (VEGF) controls the metabolic activities of adipocytes promoting the trans-differentiation from white to beige phenotype. Trans-differentiation results in an increase of energy consumption. VEGF exerts an opposite effect on brown adipose tissue, where VEGF increases oxygen supply and improves energy expenditure inducing the whitening of adipocytes.

Prevalence and Factors Associated With Fatigue in Patients With Inflammatory Bowel Disease: A Multicentre Study

BACKGROUND AND AIMS

The aims of this study were to determine the prevalence of fatigue in patients with inflammatory bowel disease [IBD], to identify the factors associated with fatigue and its severity, to assess the impact of fatigue on quality of life [QoL], and to evaluate the relationship between fatigue and sleep disorders.

METHODS

This was a prospective multicentre study conducted at 22 Spanish centres. Consecutive patients followed at IBD Units were included. Fatigue was evaluated with the Fatigue Severity Scale [FSS] and the Fatigue Impact Scale [FIS]. Quality of life and sleep quality were assessed using the IBD Questionnaire-Short Form [IBDQ-9] and the Pittsburgh Sleep Quality Index [PSQI], respectively.

RESULTS

A total of 544 consecutive adult IBD patients were included [50% women, mean age 44 years, 61% Crohn's disease]. The prevalence of fatigue was 41% (95% confidence interval [CI] = 37-45%). The variables associated with an increased risk of fatigue were: anxiety [OR = 2.5, 95% CI = 1.6-3.7], depression [OR = 2.4, 95% CI = 1.4-3.8], presence of extraintestinal manifestations [EIMs] [OR = 1.7, 95% CI = 1.1-2.6], and treatment with systemic steroids [OR = 2.8, 95% CI = 1.4-5.7]. The presence of EIMs [regression coefficient, RC = 8.2, 95% CI = 2.3-14.2], anxiety [RC = 25.8, 95% CI = 20.0-31.5], depression [RC = 30.6, 95% CI = 24.3-37.0], and sleep disturbances [RC = 15.0, 95% CI = 9.3-20.8] were associated with severity of fatigue. Patients with fatigue had a significantly decreased IBDQ-9 score [p < 0.001].

CONCLUSIONS

The prevalence of fatigue in IBD patients is remarkably high and has a negative impact on QoL. Therapy with systemic steroids is associated with an increased risk of fatigue. The severity of fatigue is associated with anxiety, depression, sleep disorders, and the presence of EIMs. Fatigue was not associated with anaemia, disease activity or anti-TNF therapy.

Phenotypic Resistance to Disinfectants and Antibiotics in Methicillin-Resistant Staphylococcus aureus Strains Isolated from Pigs

The aim of this research was to study the phenotypic resistances to disinfectants and antibiotics in strains of methicillin-resistant Staphylococcus aureus (MRSA) obtained from Canary black pigs. Analyses were performed on 54 strains of MRSA, isolated in Canary black pigs from the province of Tenerife (Spain); all of them carried the mecA gene. The strains were isolated by means of nasal swab samples of healthy pigs, collected under veterinarian supervision. Bactericidal activity of antiseptics and disinfectants was tested by means of the dilution-neutralization method. Susceptibility to the disinfectants glutaraldehyde, peracetic acid and silver nitrate was assessed, as well as to the antiseptics chlorhexidine, benzalkonium chloride and povidone iodine. Susceptibility to a wide array of antibiotics representing the main groups was determined by means of the disc diffusion method. All the strains demonstrated susceptibility to the disinfectants tested at the recommended concentration, and even to dilutions equal to or lesser than 1/16. The most effective antiseptic and disinfectant were, respectively, chlorhexidine and silver nitrate. With regard to the antibiotics, the strains proved to be multiresistant. All presented phenotypic resistance to the β-lactam antibiotics ampicillin, penicillin and cefoxitin, as well as to numerous aminoglycosides, tetracycline and trimethoprim-sulfamethoxazole. It was also observed that 61.1% of the strains were carriers of plasmids. Our results underline that in the strains such as MRSA, which show multiple resistances to antibiotics, the antiseptics and disinfectants show great efficacy. Moreover, as other authors also suggest, for the treatment and prevention of infections caused by MRSA, the use of β-lactam and aminoglycoside antibiotics may be less effective.

Tuberculosis in Anti-Tumour Necrosis Factor-treated Inflammatory Bowel Disease Patients After the Implementation of Preventive Measures: Compliance With Recommendations and Safety of Retreatment

BACKGROUND AND AIMS

Despite having adopted preventive measures, tuberculosis (TB) may still occur in patients with inflammatory bowel disease (IBD) treated with anti-tumour necrosis factor (anti-TNF). Data on the causes and characteristics of TB cases in this scenario are lacking. Our aim was to describe the characteristics of TB in anti-TNF-treated IBD patients after the publication of the Spanish TB prevention guidelines in IBD patients and to evaluate the safety of restarting anti-TNF after a TB diagnosis.

METHODS

In this multicentre, retrospective, descriptive study, TB cases from Spanish hospitals were collected. Continuous variables were reported as mean and standard deviation or median and interquartile range. Categorical variables were described as absolute and relative frequencies and their confidence intervals when necessary.

RESULTS

We collected 50 TB cases in anti-TNF-treated IBD patients, 60% male, median age 37.3 years (interquartile range [IQR] 30.4-47). Median latency between anti-TNF initiation and first TB symptoms was 155.5 days (IQR 88-301); 34% of TB cases were disseminated and 26% extrapulmonary. In 30 patients (60%), TB cases developed despite compliance with recommended preventive measures; *not performing 2-step TST (tuberculin skin test) was the main failure in compliance with recommendations. In 17 patients (34%) anti-TNF was restarted after a median of 13 months (IQR 7.1-17.3) and there were no cases of TB reactivation.

CONCLUSIONS

Tuberculosis could still occur in anti-TNF-treated IBD patients despite compliance with recommended preventive measures. A significant number of cases developed when these recommendations were not followed. Restarting anti-TNF treatment in these patients seems to be safe.