bluuebunny/crossref_metadata_2025 huggingface dataset:
An endosome-associated actin network involved in directed apical plasma membrane growth
Authors: Ríos-Barrera Luis Daniel , Leptin Maria
Published: January 2022

Membrane trafficking plays many roles in morphogenesis, from bulk membrane provision to targeted delivery of proteins and other cargos. In tracheal terminal cells of the Drosophila respiratory system, transport through late endosomes balances membrane delivery between the basal plasma membrane and the apical membrane, which forms a subcellular tube, but it has been unclear how the direction of growth of the subcellular tube with the overall cell growth is coordinated. We show here that endosomes also organize F-actin. Actin assembles around late endocytic vesicles in the growth cone of the cell, reaching from the tip of the subcellular tube to the leading filopodia of the basal membrane. Preventing nucleation of endosomal actin disturbs the directionality of tube growth, uncoupling it from the direction of cell elongation. Severing actin in this area affects tube integrity. Our findings show a new role for late endosomes in directing morphogenesis by organizing actin, in addition to their known role in membrane and protein trafficking.
Catecholamines help snakes have a change of heart
Authors: Short Ben
Published: January 2022

JGP study on python snakes reveals that the regulation of ventricular repolarization by the sympathetic nervous system is evolutionarily conserved.
Wideband compact phase shifter based on hybrid half-mode substrate integrated waveguide and spoof surface plasmon polariton
Authors: Moznebi Ali-Reza , Afrooz Kambiz
Published: January 2022

This paper proposes a wideband compact equal-length phase shifter based on the hybrid half-mode substrate integrated waveguide (HMSIW) and spoof surface plasmon polariton (SSPP) concept for the first time. The HMSIW transmission lines (TLs) with different widths result in different propagation constants. The difference of propagation constants between two HMSIW TLs with two different widths decreases as the frequency increases. Therefore, a wideband phase shifter cannot be designed by using this technique. In this paper, a series of half-butterfly grooves are etched on the top conductor layer of the HMSIW TL to compensate the phase shift. The combination of the SSPP and HMSIW structures provides a higher degree of freedom to keep the propagation constants difference constantly. Accordingly, a wideband response can be achieved by properly tuning the structure. Here, the dispersion characteristic of the butterfly-shaped HMSIW-SSPP can be adjusted by changing the width of the HMSIW and the radius and angle of the half-butterfly grooves. Moreover, the HMSIW-SSPP structure with half-butterfly grooves reduces both longitudinal and transverse dimensions of the proposed circuit. It has more slow-wave effects than the traditional counterpart with rectangular grooves. To validate the concept, a

90

∘

phase shifter is designed and fabricated on a single-layer substrate at the center frequency of 5.8 GHz covering WLAN. The simulated and measured results are in good agreement. The measured results show that the phase shifter has a fractional bandwidth of 31.7% with a phase error of

±

3.5

∘

, an insertion of

1.1
±
0.25

dB, and a return loss of higher than 13.8 dB. Also, the size of the proposed phase shifter is

0.4

λ

g

×
2.18

λ

g

.
Thermal and non-thermal ablation mechanisms in crystalline silicon by femtosecond laser pulses: classical approach of the carrier density two temperature model
Authors: Vaghasiya Hardik , Krause Stephan , Miclea Paul-Tiberiu
Published: January 2022

Laser micromachining has attracted considerable interest because of its wide range of applications across nearly all manufacturing sectors and mostly in semiconductors such as silicon. However, modern micro-manufacturing demands progressive product miniaturization, high accuracy, and high-precision material removal. For this purpose, a fundamental study of the interaction between ultrashort laser pulses and silicon will be valuable for studying ablation characteristics and ablation performance. The femtosecond laser pulse interaction with the silicon is divided into five parts: (a) the interaction of laser light with the carriers, (b) variation of the carrier density and carrier temperature, (c) energy exchange between carriers and lattice, (d) thermomechanical response of the material, and (e) ablation. The evolution of the carrier density and carrier-lattice energy coupling equation is solved simultaneously to determine the optimum value of the ablation width and ablation depth of femtosecond laser pulses on the silicon. The first time, 2D axial symmetry thermal and non-thermal ablation profiles were compared with the experimental result at fluence ranging from 0.75 to 9 J cm−2 at the wavelength of 515 nm and 180 fs laser on the silicon sample. A comparative study of damage thresholds from experiments and simulations is presented. The concordance between model calculations and experimental data demonstrates that fs laser ablation is thermal in nature in low fluence regime, whereas it is non- thermal in a high-fluence regime. Fundamental information such as the time evolution of the carrier density, carrier temperature evolution, and lattice temperature evolution can be obtained from the simulation results.
Enhanced electron–phonon coupling near an electronic quantum phase transition
Authors: Gidopoulos Nikitas
Published: January 2022

I construct a simple model to demonstrate that when the many-electron quantum state of a material is near a quantum phase transition and the vibrational motion of a phonon explores the potential energy surface near the transition point, then an impenetrable barrier appears at the potential energy surface which restricts the phonon from crossing the transition point and abnormally increases the phonon frequency. The ensuing anomalous enhancement of the electron phonon coupling is general and independent of the specific nature of the electronic quantum phase transition. Understanding and modelling this strong electron–phonon coupling may potentially lead to the design of phonon superconductors with high critical temperatures by choosing their parameters appropriately near an electronic quantum phase transition.
A study of the magneto-controlled mechanical properties and polishing performance for single-crystal SiC used as a magnetorheological-elastomer polishing pad
Authors: Hu Da , Deng Jiayun , Lu Jiabin , Yan Qiusheng , Du Canlin , Cao Jiyang
Published: January 2022

Magnetorheological elastomers (MREs) are widely used in vibration control due to their excellent magneto-controlled mechanical properties. In this research, polyurethane-based MRE polishing pads were prepared and used for the polishing of single-crystal SiC to investigate the magneto-controlled mechanical properties, the magneto-polishing effect, and the mechanism of action thereof. The results show that the pre-structuring process is affected by parameters such as mass fraction and particle size of magnetic particles in MREs and curing magnetic field strength, different chain strings that demonstrate different magnetorheological effects are formed. The greater the mass fraction of magnetic particles and curing magnetic field strength, the more the MREs exhibit magnetorheological effects, especially so when the magnetic particles size of 3 μm. A series of 90 min polishing experiments on single-crystal SiC with original surface roughness (R
a) 80 nm were conducted using an MRE pad. The results indicate that with the increase of polishing magnetic field strengths, the shear modulus of MRE polishing pads increases, the material removal rate (MRR) of the polishing process increases and R
a decreases. As the magnetic field strength is increased from 0 mT to 335 mT, the shear modulus is increased from 1.392 MPa to 1.825 MPa (an increase of 31.1%), while MRR is increased from 706.3 nm h−1 to 835.3 nm h−1 (an increase of 18.3%), R
a is decreased from 19.92 nm to 3.62 nm (an improvement in surface quality of 81.8%). The results show that the increase of the polishing magnetic field strengths changes the material modulus of the MRE polishing pads, which cause the decreases in the compressive and shear elastic deformation of the abrasive grains on the elastic substrate. This increases the positive pressure of the abrasive grains on the SiC wafer, which enhances the material-removal ability of the SiC wafer, thereby improving the surface quality of the wafer.
Effects of alpha particles on the CTEM driven zonal flow in deuterium–tritium tokamak plasmas
Authors: Hussain M. S. , Guo Weixin , Wang Lu
Published: January 2022

The effects of fusion-born alpha (α) particles on zonal flow (ZF) driven by collisionless trapped electron mode (CTEM) turbulence are analytically investigated, using gyrokinetic and bounce kinetic theories in the deuterium–tritium (D–T) tokamak plasmas. It is found that ZF growth rate is increased by α particles because of the reduction of polarization shielding as well as enhancement of CTEM instability. The results of this paper are qualitatively consistent with the enhancement of the level of residual ZF by α particles in (Cho and Hahm 2019 Nucl. Fusion
59 066026). The parametric dependence of ZF growth rate is also analyzed. The increment of ZF growth rate is further enhanced by α particles with higher fraction and steeper density profile. Besides, the dependence of ZF growth rate on electron temperature T
e could be changed qualitatively by the presence of α particles when T
i = T
e. Moreover, the difference of ZF growth rates in the presence of α particles with slowing down and equivalent Maxwellian distribution functions is very weak. These results could be very important for accurate prediction of the confinement in the future burning plasmas such as International Thermonuclear Experimental Reactor and China Fusion Engineering Test Reactor.
OP20 Perianal fistulas are characterised by expansion of interleukin-22 producing invariant natural killer T-cells and CD4+ T-cells which drive dysregulation of the extracellular matrix
Authors: Constable L , Iqbal N , Cozzetto D , Hart A , Tozer P , Powell N
Published: January 2022

Background

Perianal fistulas are a common complication of Crohn’s disease (CD) affecting approximately 25% of patients, often predicting a more complicated disease course. Dysregulated immune responses and epithelial-to-mesenchymal transition (EMT) are hypothesised to contribute to fistulizing disease; however, they have been poorly studied. In this study, we investigated the immune phenotype of patients with perianal fistulizing disease and its relationship with tissue remodelling.

Methods

Immune cells were isolated from fistula curettage samples (n=31) and paired peripheral blood from patients with perianal Crohn’s (pCD) or idiopathic fistulizing disease. Multiparameter flow cytometry was performed to evaluate lymphocyte populations including invariant natural killer T-cells (iNKTs), gamma-delta (γδ) T-cells, CD161+ mucosal-associated invariant T-cells (MAIT), CD4+ T-cells and CD8+ T-cells. Gene expression profiling of fistula (Crohn’s n=11, idiopathic n=11) and rectal tissue (Crohn’s n=9, idiopathic n=9) was performed by RNA-sequencing. Cellular deconvolution of transcriptomic data using CIBERSORTx was performed to define the cellular phenotype of perianal fistulas. Cytokine treated intestinal epithelial organoids were used to probe the impact of selective cytokines on disease relevant pathways in perianal fistulas, using gene-set enrichment analysis (GSEA).

Results

Perianal fistulas were characterised by expansion of iNKTs and CD4+ T-cells when compared to peripheral blood. Deeper analysis of the phenotype of these populations revealed enrichment of CD8- CD4- CD161+ iNKTs producing interleukin-22 (IL22), and CD4+ CD161+ T-cells producing interleukin-13 (IL13) and IL22. Surprisingly, pCD and idiopathic fistulas displayed similar immunophenotypes. Fistulas exhibited distinct transcriptional profiles to rectal tissue, although the phenotype of pCD and idiopathic fistulas appeared similar. Pathways related to the extracellular matrix (ECM) and EMT were more activated in fistulas compared to rectum. Gene-set enrichment analysis and cellular deconvolution identified an increase in the abundance of iNKTs, activated memory CD4+ T-cells, activated NK cells and neutrophils in fistula versus rectal tissue. IL13, IL22 and TNFα responsive transcripts were enriched in fistula tissue, and in the case of IL22, was shown to regulate key matrisome components.

Conclusion

Perianal fistulas are characterised by increased infiltration of CD161+ iNKT cells and CD4+ T-cells, producing IL22 and IL13. These pro-inflammatory cytokines are likely important drivers of ECM dysregulation and tissue remodelling in perianal fistulizing disease.
OP40 Efficacy of risankizumab induction and maintenance therapy by baseline Crohn’s Disease location: Post hoc analysis of the phase 3 ADVANCE, MOTIVATE, and FORTIFY studies
Authors: Bossuyt P , Bresso F , Dubinsky M , Ha C , Siegel C , Zambrano J , Kligys K , Kalabic J , Zhang Y , Panaccione R
Published: January 2022

Background

In Crohn’s disease (CD), disease location affects treatment outcomes.1 This post hoc analysis assessed the efficacy of risankizumab (RZB), an interleukin 23 p19 inhibitor, by disease location.

Methods

In ADVANCE (NCT03105128) and MOTIVATE (NCT03104413), patients with moderately to severely active CD and intolerance or inadequate response to conventional and/or biologic therapy (ADVANCE) or to biologic therapy (MOTIVATE) received intravenous (IV) RZB induction therapy or placebo (PBO) for 12 weeks. Patients achieving clinical response to IV RZB induction were re-randomised in a maintenance study (FORTIFY, NCT03105102) to receive subcutaneous (SC) RZB or SC PBO (ie, withdrawal) for 52 weeks. This post hoc analysis included patients who received RZB 600 mg IV in either ADVANCE or MOTIVATE and patients who received RZB 360 mg SC in FORTIFY. Clinical and endoscopic outcomes were evaluated in patient subgroups stratified by CD location at baseline (ileal only, colonic only, ileal-colonic) using non-responder imputation incorporating multiple imputation to handle missing data due to COVID-19.

Results

At week 12, significantly greater proportions of patients receiving RZB 600 mg IV achieved the co-primary endpoints CD Activity Index (CDAI) clinical remission and endoscopic response vs PBO in the colonic only (n = 190) and ileal-colonic (n = 252) subgroups (P < .001; Figure 1A–1B). At week 12, statistically higher proportions of RZB-treated patients achieved the composite endpoint CDAI clinical remission and endoscopic response, as well as endoscopic remission in the colonic only and ileal-colonic subgroups vs PBO (P < .001; Figure 1C–1D). At week 52, significantly greater proportions of patients receiving RZB 360 mg SC achieved the co-primary endpoints CDAI clinical remission and endoscopic response, composite CDAI clinical remission and endoscopic response, and endoscopic remission vs withdrawal (PBO SC) in the colonic only (n = 59) and ileal-colonic (n = 67) subgroups (P ≤ .05; Figure 2A–2D). In patients with endoscopic remission after 12 weeks of IV RZB (week 0 of maintenance), significantly more RZB-treated patients achieved sustained endoscopic remission at week 52 vs withdrawal (PBO SC) in the colonic only and ileal-colonic subgroups (P ≤ .01; Figure 2E). At weeks 12 and 52, efficacy rates were numerically lower in ileal only CD relative to colonic only and ileal-colonic CD. Results for ileal only CD are limited by the small number of patients in the subgroup (induction, n = 85; maintenance, n = 15).

Conclusion

RZB induction and maintenance therapy was effective in patients with moderately to severely active CD with greater benefits observed in patients with any colonic involvement.
DOP64 Pathogenic RIPK1 Mutations Cause Infantile-onset IBD with Inflammatory and Fistulizing Features
Authors: Sultan M , Millman P , McCourt B , Kol N , Lev A , Matar M , Barel O , Shamir R , Wilschanski M , Konnikova L , Somech R , Shouval D
Published: January 2022

Background

Genetics plays a key role in the pathogenesis of inflammatory bowel disease (IBD). With the expanding use of next-generation sequencing, >70 different monogenic disorders associated with IBD have been identified, and most of them present in the first years of life. Recently, several patients with severe IBD were identified to harbor pathogenic mutations in Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) gene, which regulates necroptosis, a necrotic cell death mechanism. We present the clinical features, genetic analysis and immune work-up of three patients with infantile-onset IBD resulting from novel RIPK1 mutations.

Methods

Whole exome sequencing was performed in three patients with severe infantile-onset IBD, along with sanger sequencing for conformation. Mass cytometry time of flight was conducted for in-depth immunophenotyping, including cytokine secretion analysis following lipopolysaccharide (LPS) or Phorbol myristate acetate with ionomycin (PMA-I), on one of the patient’s peripheral blood mononuclear cells, and compared to control subjects and patients with Crohn’s disease.

Results

All patients, born to consanguineous Muslim families, presented with severe colitis and multiple perianal fistulas in the first months of life, without severe or atypical infections. One of the patients had a partial response to high doses of inlfliximab and azathioprine, while another one failed to respond to adaliumab and later to low dose anakinra, an IL-1 receptor antagonist. Genetic studies identified novel and pathogenic genetic variants in the RIPK1 gene in all patients, that were confirmed by Sanger sequencing. Using mass cytometry time of flight unbiased clustering analysis, we identified peripheral immune dysregulation in one of these patients, characterized by an increase in IFNγ CD8+ T cells along with a decrease in monocytes, dendritic cells and B cells. Moreover, RIPK1-deficient patient’s immune cells exhibited decreased IL-6 production in response to LPS across multiple cell types including T cells B cells and innate immune cells.

Conclusion

Mutations in RIPK1 should be considered in very young patients presenting with colitis and perianal fistulas. Given RIPK1’s role in both immune cells (and specifically in inflammasome activation), and epithelial cells, it is unclear whether immunosuppressive medications (including IL1 blockade) as well as allogeneic hematopoietic stem cell transplantation can suppress or cure the hyper-inflammatory response in these patients. Additional studies in humans are required to better define the role of RIPK1 in regulating intestinal immune responses, and how treatment can be optimized for patients with RIPK1 deficiency.
P020 Differential expression of miR-424-5p and miR-378c in stenotic and penetrating lessions of Crohn’s Disease associates with altered transcription of genes involved in vascular regulation
Authors: Coll S , Seco M , Bauset C , Lis L , Cosín-Roger J , Ortiz-Masia D , Gisbert-Ferrandiz L , Barrachina D , Calatayud S
Published: January 2022

Background

Crohn′s disease (CD) is often complicated by the appearance of intestinal stenosis (B2 behaviour) or fistulas (B3 behaviour), and the factors determining the pattern of disease and the etiology of these lesions, both associated with fibrosis and requiring surgery, are poorly defined. Our aim has been to detect transcriptomic alterations in intestinal tissues affected by stenosis or fistulas, and have centred our attention in genes affecting vessel formation and function as potential contributors to these lesions.

Methods

We conducted a small RNA sequencing profiling on ileal surgical resections from CD patients with B2 (n=10) or B3 (n=10) behaviour. We obtained a sample from affected tissue and the paired non-affected ileum from each patient.

Results

Tissues affected by stenotic or penetrating lesions present a differential expression of two pro-angiogenic miRNAs (Fig1A) and an increased expression of genes associated with vascular regulation (Fig1B), and both alterations are more pronounced in penetrating lesions. The expression of this set of genes shows a generalized and significant correlation with that of the pro-angiogenic miRNAs (negative with the down-regulated miR-378c, positive with the up-regulated miR-424-5p, Fig1C), especially in the affected tissue.

Fig1. Expression of pro-angiogenic miRNAs (A) and of genes associated with vascular regulation (B) in tissues from stenotic (B2) and penetrating (B3) lesions of CD patients. Data represent normalized counts of each RNA and are expressed as mean±SEM (A) or mean (B). Data in (C) correspond to Pearson’s R. Significant differences vs corresponding non-affected tissue are represented by *P<0.05 (paired t-test) and #P<0.05 (ANOVA+Tukey test)

Conclusion

Ileal tissues from CD patients affected by stenosis or penetrating injuries present a local alteration in the expression of miRNAs with pro-angiogenic functions that probably contributes to the up-regulation of genes associated with vessel formation and to the modification of the vascular compartment in these lesions.
P036 Identification and functional analysis of stromal subsets in experimental IBD mouse models
Authors: Zhou Z , Plug L G , de Jonge-Muller E S M , van de Beek L M , Brands L , van der Meulen-de Jong A E , Hawinkels L J A C , Barnhoorn M C
Published: January 2022

Background

Single cell RNA sequencing data from the inflamed colon of inflammatory bowel disease (IBD) patients revealed the presence of different stromal cell/fibroblast subsets and showed their importance in IBD pathology. Up to now, it is unknown if and how the stroma cells affect disease progression. In this study we compared the stromal cell subsets in three IBD mouse models and explored the interaction between these stromal subsets and epithelial cells.

Methods

Stromal cell subset markers, including CD55, C-X-C motif chemokine 12 (CXCL12), podoplanin (PDPN), CD90 and CD73, were analyzed in the inflamed murine colon by flow cytometry in interleukin (IL)-10 knockout (KO) mice, dextran sulfate sodium(DSS)-induced colitis and the T cell transfer model. In order to explore the changes in stromal subsets upon colitis induction in vitro, short hairpin RNAs were used to silence target gene expression of these cellular markers in murine fibroblasts. Fibroblast proliferation and migration was studied in addition to the effects on immune cell trafficking and tissue regeneration.

Results

In all three colitis models, an increase in the total amount of stromal cells was observed. The percentages of PDPN+ and CD73+ stromal cells significantly increased during colitis in the IL-10 KO mice, while the percentage of CD55+, CD90+ and CXCL12+ stromal cells decreased. For the T cell transfer model, the abundance of CD73+, CD90+ and CD55+ stromal cells was enriched, while the percentage of CXCL12+ stromal cells was reduced. Interestingly, in contrast to the two other, in the DSS-mice the percentage of CXCL12+ stromal cells was significantly increased. In vitro experiments showed the importance of CD55 and CXCL12 for fibroblast proliferation and CD55 for their migration. Furthermore, the fibroblast supernatant obtained after the knockdown of CXCL12 decreased epithelial cell wound healing. On the contrary, knock-down of CD90 in the fibroblasts improved epithelial migration. Current experiments explore the immune regulatory properties of the fibroblast subsets.

Conclusion

The composition of stromal cell subsets is significantly changed in experimental colitis and differs between three established colitis mouse models. Therefore they may possibly reflect different human IBD subtypes observed in the clinic. Finally the defined subsets influence fibroblast behavior and epithelial regeneration.
P042 Succinate promotes the conversion from white to beige adipose tissue in Crohn’s Disease
Authors: Montfort-Ferré D , Menacho M , Caro A , Espina B , Boronat-Toscano A , Nuñez-Roa C , Martí M , Espin E , Vendrell J , Fernández-Veledo S , Serena C
Published: January 2022

Background

Crohn’s disease (CD) is characterized by severe transmural inflammation with subsequent destruction of the intestinal barrier. Bacterial infiltration across this leaky gut facilitates access to the mesenteric fat and the development of a subsequent inflammatory reaction in the surrounding adipose tissue named creeping fat (CF). Dysbiosis in CD patients has been associated with an increase in succinate-producing bacteria and a decrease in succinate-consuming bacteria. In fact, elevated succinate levels have been found in the intestine and feces of CD patients. Furthermore, succinate is an inductor of beige adipogenesis in white adipose tissue progenitors.

Methods

Visceral and subcutaneous adipose tissue biopsies (VAT and SAT), serum, and plasma were obtained from a cohort of active CD (n=20), inactive CD (n=12), and control group (n=15). From adipose tissue biopsies, adipose-derived stem cells (ASCs) and adipose tissue macrophages (ATMs) were isolated. Different experiments were performed such as protein uncoupling protein 1 (UCP1)-immunohistochemistry and immunofluorescence, gene expression studies, adipose tissue explants, proteomic analysis of ASCs, succinate determinations, bio-impedancemetry, and infrared photographs.

Results

Succinate treatment increased markers of beige adipose tissue in ASCs from controls and inactive CD patients (Fig. A). Surprisingly, the markers of beige adipose tissue were already high in ASCs isolated from active CD, due to being exposed to an environment with high levels of succinate in vivo. Proteomic analysis of isolated CD-ASCs revealed that these cells secrete beige adipose tissue-related proteins compared to Control-ASCs (Fig. B). Furthermore, bacterial translocation increases the conversion of pre-adipocytes from white to beige adipose tissue in CD individuals (Fig. C). Immunohistochemical study of UCP-1, confirms increased staining in adipose samples from CD patients from both depots (SAT and VAT) (Fig. D). Altogether, adipose tissue depots from CD patients had a conversion from white to beige adipose tissue with a high protein UCP1-gene expression. Thermic images show an increase of temperature in the intestinal area of active CD patients that is not observed in inactive CD patients or the control group.

Conclusion

Understanding the role of beige adipose tissue in CD could help develop new therapeutic or diagnostic strategies in these patients.
P047 Effect of infliximab and vedolizumab on M1 and M2 macrophages derived from THP-1 cells
Authors: Notararigo S , Viñuela-Roldán J , Zurita-Gonzalez M J , Dominguez Medina E , Dominguez-Munos J E , Barreiro-de Acosta M
Published: January 2022

Background

Inflammatory bowel diseases encompass two pathologies affecting the digestive tract, Crohn’s disease (CD) and ulcerative colitis (UC). They are characterized by a high and chronic inflammatory rate, resulting from activation of the intestinal immune system and increased permeability of the intestinal barrier leading to lesions in the intestinal tract. Non-classical CD14- CD16+ monocytes, are recruited to the focus of inflammation from the peripheral blood and preferentially differentiate to anti-inflammatory macrophages CD206+ CD163+ HLA-DR- in the intestine, playing a key role in the repair of such lesions. In some cases, treatment with biologics, such as vedolizumab, could interfere with this biological process leading to a modification of the innate immune response. Previous results showed that CD and UC had a different distribution of non-classicalmonocytes, leading to the hypothesis that treatment with biologic could modulate macrophage wound healing response.

Methods

Macrophages derived by THP-1 cells were polarized to M0, after PMA treatment, followed by LPS and IFN-γ for M1 macrophages, or IL-4 and IL-13 for M2 macrophages. To assess the effect of biologics on macrophage immune response, Infliximab (IFX) and Vedolizumab (VDZ) were added independently to the cell cultures until polarization process finalized. Immunophenotyping of M0, M1 and M2, and transcription factor expression profiling of pSTAT-1, pSTAT-6 and pNFκB, were carried out by flow cytometry. Cytokine production of IL-6, TGF-β and IL-10, was performed by ELISA immunoblot. Macrophages immune response was assessed with wound healing assay with Caco-2.

Results

Immunophenotyping revealed that M1 macrophages increased the expression of surface markers like HLA-DR, CD38 and reduced CD11c, vs. M0 macrophages, indeed transcription factor expression of pSTAT-6 and pNFκB were modulated. M2 macrophages showed the decrease of CD163 and HLA-DR vs. M0 macrophages, while no significant effect was observed for CD38 and CD206. Transcription factor expression revealed that pSTAT 6 incremented vs. M0. Cytokine profiling showed a clear difference between the tree macrophages types. Finally wound healing assay with Caco-2 revealed how biologic interfered with innate immune response.

Conclusion

Our results demonstrated that the treatment administration could be responsible of macrophage differential immune response, especially upon biologic treatment. These findings could lead to support the establishment of precision medicine in order to modulate a suitable macrophage response.
P070 Novel long-acting lipidated interleukin-22 normalises colonic inflammation in an acute DSS colitis model
Authors: Van De Bunt M , Norrild J C , Sass-Ørum K , Kjølbye A L , Jorgensen R
Published: January 2022

Background

Most current treatments and new agents in clinical development for Inflammatory Bowel Disease (IBD) focus on inhibition of excessive inflammation. However, clinical remission rates for IBD have reached a plateau. New approaches directly improving mucosal healing, a process associated with reduced hospitalizations and long-term remission, therefore have great potential for addressing the unmet need. The cytokine interleukin-22 (IL-22) plays a key role in epithelial healing and has shown early proof-of-concept as a potential drug class in a phase 1 trial in Ulcerative Colitis. Here we present results from a mouse model of colitis on the efficacy of lipidated IL-22 analogues, which maintain more native-like molecular properties than current IL-22 modalities in development.

Methods

Chow-fed female C57Bl/6JRj mice were randomized to 4 groups (n=8 per group) based on body weight. Three groups received 2.5% (w/v) Dextran Sulfate Sodium (DSS) in the drinking water for 7 days from the start of the study. Animals receiving water without DSS served as healthy controls. Mice in the DSS groups received vehicle or lipidated IL-22 intraperitoneally at two dose levels for the entire duration of the study (10 days). At termination, plasma was sampled for assessment of target engagement biomarkers and intestines were removed and measured for weight and length before stereological analysis.

Results

Mice subjected to DSS developed colitis characterized by sustained weight loss and bloody diarrhoea. Vehicle dosed DSS mice showed clear histological features of colitis, with significantly (P<0.05) increased weight/length ratio of the colon as well as colonic mucosal, submucosal and inflammation volumes compared to healthy controls. Treatment with lipidated IL-22 significantly (P<0.05) improved all these parameters except mucosal volume compared to vehicle dosed DSS mice; in particular colonic inflammation volume was normalized to healthy control levels. Dose-dependent biomarker responses (e.g. Peptide YY levels) confirmed target engagement of the lipidated IL-22.

Conclusion

Novel long-acting lipidated IL-22, which acts on epithelial repair mechanisms, demonstrated strong improvements in histological parameters with normalisation of colonic inflammation in a DSS model of colitis. These beneficial effects were accompanied by dose-dependent increases in target engagement biomarkers. The underlying lipidation technology used for engineering these compounds has validated best in class potential in marketed treatments due to its molecular properties (e.g. size and potency). Clinical trials to assess safety and efficacy of lipidated IL-22 are expected to commence early 2023.
P074 SZN-1326 promotes colonic mucosal healing in an acute injury model of IBD by first accelerating epithelial regeneration and secondarily reducing inflammation
Authors: Fletcher R , Xie L , Phipps J , Sanman L , Deshmukh S , Shah D , Hill N , Liu A , Gupta S , Sura A , Chen H , Ye J , Yeh W C , Li Y , Lu C
Published: January 2022

Background

Wnt signaling plays critical roles in regulating intestinal stem cell maintenance and differentiation. The inflammatory bowel disease, ulcerative colitis (UC), is characterized by epithelial lesions, and there is a need for therapies that promote mucosal healing in addition to limiting inflammation. The Surrozen proprietary Wnt mimetic, SZN-1326, is a FZD5,8 and LRP6-specific, full-length, effectorless, bi-specific IgG1 molecule that is well-suited for impacting the intestinal epithelium where FZD5 is highly expressed. Previously, we have shown that in an acute dextran sodium sulfate (DSS) epithelial injury model, where 4% DSS was provided in the drinking water for seven days followed by 1% DSS until termination at day 10, a single dose of SZN-1326 at 1 mg/kg or higher on Day 4 robustly induced intestinal epithelial healing and reduced inflammation, and we wanted to understand more thoroughly the mechanism underlying this activity.

Methods

Here, we report on additional studies in the same DSS model including scRNA-seq and tissue analysis timepoints at days 3, 4, 5, 6, 7, and 10 (6-days post treatment).

Results

DSS impacted all tissue layers by day 3. The direct effect of SZN-1326 on the epithelium occurred as early as 24-hours after treatment (day 5 of the experiment). SZN-1326 induced and/or increased Wnt target and cell cycle gene expression in the epithelium leading to progenitor cell expansion, and following this wave of enhanced progenitor proliferation, the cells transited toward colonocyte differentiation more quickly than the progenitor cells in control treated samples. Even in the presence of 1% DSS, relative to the anti-GFP treatment samples, the absorptive cell lineage in the SZN-1326-treated epithelium was more similar at a transcriptomic level to the uninjured condition. In addition, when comparing SZN-1326 treatment to anti-GFP at 24-hours, there were no differentially expressed genes in either the stroma or immune cells. However, analysis of the later timepoints revealed a robust reduction in cytokine/inflammatory signaling in the stromal and immune cells and a drastic reduction of infiltrating monocytes and neutrophils, which we validated in the tissue by immunohistochemistry. We detected this reduction by 72-hours after treatment, and it was more pronounced by day 10, 6-days after treatment, implicating a secondary effect.

Conclusion

In this acute damage context, SZN-1326 promoted mucosal healing by transiently inducing epithelial progenitor cell expansion and accelerating epithelial repair. Secondary to its initial impact on the epithelium, SZN-1326 reduced stromal and immune cytokine signaling and immune cell infiltration.
P108 Identifying Patient-Centered Future Research Priorities: A Report from the Patient Reported Outcomes after Pouch Surgery (PROPS) Delphi Consensus Study
Authors: Cavallaro P , Bordeianou L
Published: January 2022

Background

The Patient Reported Outcomes after Pouch Surgery (PROPS) Delphi Consensus Study recently described Ileoanal Pouch Syndome – the constellation of functional outcomes that should be the focus of future research. Importantly, several additional items not related to bowel function were identified by patients as critical to their quality of life. The aim of this abstract is to highlight these additional items.

Methods

Three panels of expert stakeholders were chosen to correlate with the clinical scenario of the multidisciplinary team that cares for pouch patients: (A) patients, (B) colorectal surgeons, (C) gastroenterologists/other clinicians. IPAA patients were recruited by advertisements on the social media pages of a national patient advocacy groups. Clinicians were recruited by a 14 member scientific committee with the aim of selecting experts in inflammatory bowel disease and IPAAs. A starting list of items was generated by systematic literature review. Three rounds of Delphi surveys were employed to select high priority items based on an a priori threshold. Participants had the opportunity to suggest additional symptoms not included in the starting list. A final online consensus meeting with representation from all three expert panels was held to finalize a consensus statement.

Results

After three rounds of voting, 195 patients, 62 colorectal surgeons, and 48 gastroenterologists/other specialists completed all three rounds. In the patient group, 95% had UC and J-pouch anatomy. In the early Delphi rounds, approximately 74% of patients identified impact on sexual function/intimacy as a high priority outcomes, while 70% of patients identified impact on ability to conceive as a high priority. Similarly, 78% of patients believed that risk of pouchitis was a high priority, compared to 47% of surgeons and 66% of gastroenterologists. Furthermore, patients participating in the subsequent online focus groups and final consensus meeting felt strongly that future research on delivery of care, long term follow up, and proper consent before surgery (including accurate counseling on function and perception of being “cured”) were critical areas for future research.

Conclusion

PROPS was the first study to identify key functional outcomes after pouch surgery with direct input from a large panel of IPAA patients. The inclusion of patients in all stages of the consensus process allowed for a true patient-centered approach in defining the core domains that should be focused on in future studies of pouch function. In addition to the identification of key bowel function outcomes, the study highlighted additional patient-centered core outcomes that clinicians should focus future research efforts on.
P128 Accuracy of the combination of transabdominal and transperineal ultrasound for the evaluation of Ulcerative Colitis activity
Authors: Terracciano F , Bossa F , Marra A , Valvano M R , Carparelli S , Ippolito M A , Perri F
Published: January 2022

Background

Transabdominal Bowel Ultrasound (TBUS) is useful technique to assess disease activity and extent in patients with ulcerative colitis (UC); however, the evaluation of the rectum by TBUS is difficult. Recently, transperineal ultrasound (TPUS) has been proposed as a useful diagnostic tool in the evaluation of rectal disease. The aim of the study is to to assess the concordance between the combination of TPUS/TBUS and endoscopy in adult patients with UC.

Methods

Fifteen consecutive adult patients with UC were prospectively enrolled from June to November 2021. Disease activity was determined using Partial Mayo Score (PMS) and Mayo Endoscopic Subscore (MES). TBUS and TPUS were performed within a week from endoscopy. MES ≤ 1, bowel wall thickness ≤ 3mm in the colon and ≤ 4mm in the rectum were defined as remission. A concordance analysis comparing endoscopy and US was performed by kappa statistics

Results

Ten patients were male (66%) and 8 female (34%), with a median age of 39± 13,9. Two patients had a pancolitis, 6 a distal colitis, and 3 a proctitis. 4 patients were in remission. The agreement between endoscopy and rectal evaluation with TBUS was fair (k =0.40), while the agreement with TPUS was excellent (k =0.86). The evaluation of the colon with TBUS showed good concordance in the right colon (k= 0.63), left colon (k=0.65), and sigmoid colon (k=0.72), and excellent agreement in the transverse colon (k= 1).

Conclusion

These preliminary data showed that the combination of TBUS and TPUS allows to easily and accurately study all the segments of the large intestine in patients with UC, overcoming the limitation related to the reduced accessibility to the rectum with only trans abdominal approach.
P146 Initial response to induction treatment more important than type of induction treatment for achieving sustained steroid free remission at 1 year in new-onset paediatric Crohn’s disease
Authors: Klomberg R , van der Wal H , Sarbagili C , Kemos P , Ruemelle F , Croft N , de Ridder L , Levine A
Published: January 2022

Background

For paediatric patients with high risk of complicated Crohn’s disease (CD) [stricturing or penetrating disease], paediatric guidelines recommend upfront anti-tumor necrosis factor-alpha (ATA). Early ATA therapy has been demonstrated to result in higher steroid- and surgery-free remission rates at 1 year than induction with conventional treatment (CONV) [Exclusive Enteral Nutrition (EEN) or corticosteroids followed by immunomodulatory therapy]. However, it is unknown whether either type of induction treatment or achieving steroid free remission (SFR) at 3 months is a more important predictor of sustained SFR (SSFR) at 1 year. Therefore, we aimed to evaluate the independent effect of early ATA use after achieving induction of remission on sustained SFR (SSFR) rates at 1 year in an international prospective observational study.

Methods

Since January 2017, children (0–18 years) with newly-diagnosed CD were prospectively enrolled in 28 European and Asian paediatric IBD centers. Extensive demographic and clinical data were collected at baseline, and at 1, 3, 6 and 12 months. The primary outcome was SSFR at 1 year, defined as a weighted Paediatric CD Activity Index (wPCDAI) <12.5 without steroids at 3, 6, and 12 months. Secondary outcomes included SFR at 3 and 12 months, and treatment escalation to ATA. Outcomes were compared between the early ATA induction treatment group (defined as ATA within 3 months after diagnosis) and the CONV induction treatment group (EEN or corticosteroids), using χ 2 tests.

Results

Up to July 2021, 235 children with new-onset CD were included and completed at least 1 year of follow-up (61.7% male, median age 13.7 [IQR 11.4–15.0]). At 1 year, 62/203 (30.5%) achieved SSFR. Patients that received early ATA were more likely to achieve SSFR compared to patients with CONV (35/79 [44%] vs. 27/110 [25%], p=0.004). After induction treatment, 99/213 [47%] achieved SFR at 3 months. Patients with early ATA had higher rates of SFR at 3 months (48/84 [57%]) than those with CONV (51/129 [40%], p=0.012), and higher rates of low faecal calprotectin (67% vs. 17%, p<0.001) or low CRP (< 5 mg/l) (82% vs. 53%, p<0.001). Of those patients in SFR at 3 months, 71% achieved SSFR, which was not significantly different between those in SFR at 3 months with early ATA vs. with CONV (35/45 [78%] vs. 27/43 [63%], p=0.12).

Conclusion

While only one-third of paediatric CD patients achieve SSFR at 1 year, 71% of patients achieve SSFR after having achieved SFR at 3 months. Patients with early ATA had higher rates of SFR at 3 months and SSFR at 1 year than those without early ATA. Remission at 3 months was found to be more important for SSFR than type of induction treatment, highlighting the importance of initial response to induction treatment.
P153 The impact of seton use on clinical and patient-reported outcomes in Crohn’s disease perianal fistulas: findings from a systematic literature review
Authors: White I , Karki C , Geransar P , Worsfold A , Leisle L , Junker S , Fleshner P
Published: January 2022

Background

Complex perianal fistulas are a common complication of Crohn’s disease, and are treated with both surgical and medical intervention. Irrespective of treatment strategy, seton placement is used to facilitate fistula drainage and prevent recurrent abscess formation. The aim of this systematic literature review was to summarize available evidence on clinical outcomes associated with seton use for symptomatic relief and treatment of complex Crohn’s perianal fistula (complex CPF).

Methods

Electronic databases (MEDLINE, Embase, EBM Reviews and Econlit) were searched for articles (1980–present) reporting data on the use of seton in patients with complex CPF. Seton use as a preparatory procedure for surgery was excluded. Articles were screened for relevance using pre-defined PICOS-T criteria and data on outcomes of interest including clinical remission, fistula recurrence, adverse events, and patient-reported outcomes (PROs) were extracted. Data were summarized qualitatively and analysed using descriptive statistics.

Results

Overall, 56 articles underwent data extraction (43 full texts, 13 congress abstracts; 50 observational studies, 6 clinical trials). Duration of seton use was reported in 23 studies (range: 4–277 weeks). Clinical response and/or remission following seton use or seton use + biologics were defined by 35 articles. Definitions were variable, with most relating to fistula closure, symptom improvement or cessation of fistula drainage. Remission rates in patients treated with seton only and seton + infliximab were 13–75% (9 articles) and 23–100% (14 articles), respectively (Figure). Definitions of recurrence (e.g. fistula discharge or reopening) were reported in 16 observational studies and varied. Most articles defined clinical outcomes (e.g. prior removal of seton, closure or healing of the fistula tract, or response) before recurrence was measured. Overall, recurrence rates in patients treated with seton only and seton + infliximab were 4–68% (9 articles) and 0–50% (12 articles), respectively (Figure). The rate of recurring abscesses (3 articles) or local sepsis (2 articles) and the frequency of new abscess (7 articles) or fistula development (3 articles) was 7–43%, 31–61%, 10–47% and 9–26%, respectively. Rates of adverse events or complications after seton use (14 articles) ranged from 0–77%. PROs measuring functional outcomes, faecal incontinence and quality of life were reported by 6 articles.

Conclusion

Owing to a lack of standardized definitions for clinical outcomes following seton use in complex CPF, comparison of study results was not possible. Standard clinical outcome definitions are needed to permit data comparability, and are vital to guide treatment plans to improve outcomes for patients with complex CPF.