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Aim: To determine differences in surgical procedures and clinical characteristics at the time of surgery between native bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) in patients being followed up after aortic valve surgery (AVS). Methods: In this retrospective cohort study in a non-academic hospital, we identified patients who had a surgeon’s report of the number of native valve cusps and were still being followed up. We selected patients with BAV and TAV, and used multivariable regression analyses to identify associations between BAV-TAV and pre-specified clinical characteristics. Results: Of 439 patients, 140 had BAV (32%) and 299 TAV (68%). BAV patients were younger at the time of surgery (mean age 58.6 ± 13 years) than TAV patients (69.1 ± 12 years, p < 0.001) and were more often male (64% vs 53%; p = 0.029). Cardiovascular risk factors were less prevalent in BAV than in TAV patients at the time of surgery (hypertension (31% vs 55%), hypercholesterolaemia (29% vs 58%) and diabetes (7% vs 16%); all p < 0.005). Concomitant coronary artery bypass grafting (CABG) was performed less often in BAV than in TAV patients (14% vs 39%, p < 0.001), even when adjusted for confounders (adjusted odds ratio (adj.OR) 0.45; 95% CI: 0.25–0.83). In contrast, surgery of the proximal aorta was performed more often (31% vs 11%, respectively, p < 0.001; adj.OR 2.3; 95% CI: 1.3–4.0). Conclusions: Whereas mechanical stress is the supposed major driver of valvulopathy towards AVS in BAV, prevalent cardiovascular risk factors are a suspected driver towards the requirement for AVS and concomitant CABG in TAV, an observation based on surgical determination of the number of valve cusps.

Malaria remains a major cause of mortality in the world and an efficient vaccine is the best chance of reducing the disease burden. Vaccination strategies for the liver stage of disease that utilise injection of live radiation-attenuated sporozoites (RAS) confer sterile immunity, which is mediated by CD8

Background Bicuspid aortic valve (BAV) may frequently lead to aortic dilatation with risk of aortic dissection. In patients with BAV both familial clustering and aortic dilatation in first-degree relatives (FDR) without BAV has been demonstrated. Based on these findings the ESC Aortic Guidelines recommend to consider screening of FDR, while the ACC/AHA Guidelines on Valvular Heart Diseases consider screening of FDR only if the index patient has associated aortopathy. Currently, no data about the effectiveness of screening is available. Purpose To investigate the yield of screening FDR of patients with isolated BAV and to explore subgroups with FDR of patients who had needed surgery or of patients with aortic dilatation. We hypothesized that aortic dilatation (>40mm) in the index patient is not a risk factor for BAV in FDR. Methods From 2012, patients with BAV visiting the outpatient clinic of a teaching hospital, received information advising cardiac screening of FDR. FDR of patients with isolated BAV who were referred, were included. From the 10 index patients from other hospitals, information was retrieved. [Fig.1] Results Referred were FDR from 118 index patients (mean age 60 years, standard deviation [SD] 14, range 15–90 years, 82 males [70%]). Of all index patients 63 (53%) had undergone aortic valve replacement, including concomitant ascending aorta replacement in 25 (21%). In the non-operated index patients, 31 (26%) had dilatation (>40mm) of sinus of Valsalva and/or tubular ascending aorta. Screened were 257 FDR (median 2 per index patient) comprising 20 parents (8%), 103 siblings (40%) and 134 offspring (52%). Mean age of FDR was 48 years (SD16, range 4–83 years) and 89 subjects (42%) were male. The diagnostic imaging modality was echocardiography in 240 cases (93%) and MRI in 17 cases. Ten FDR had an already known BAV and were not included in the screening. Among the 257 FDR, we diagnosed 12 new BAV (4.7%, 95% confidence interval [CI]2.9–8.0%) (mean age 44 years, 50% male). Additionally, we diagnosed 23 new isolated aorta dilatations (8.9%; 95% CI 6.0–13%) at level of sinus of Valsalva and/or tubular ascending aorta (mean age 57 years, 18 [78%] were male) [Fig. 1]. Among them, 11 had hypertension. FDR (n=147) of index patients with BAV and previous aortic valve surgery (n=63), had a risk ratio (RR) of 2.25 (95% CI 0.62–8.10) of having a BAV. FDR (n=126) of index patients with BAV and repaired or unrepaired aortic dilatation (n=56) had RR 0.35 (95% CI 0.10–1.25) of having a BAV. Conclusions Screening FDR of patients with isolated BAV resulted in a reasonable yield of 14% new cases with BAV or isolated aortic dilatation. The RR of the subgroup with aorta dilatation did not justify the limitation of the FDR as suggested in the ACC/AHA Guidelines. Figure 1. Flowchart of screening and result Funding Acknowledgement Type of funding source: None

Liver resident-memory CD8+ T cells (TRM cells) can kill liver-stage Plasmodium-infected cells and prevent malaria, but simple vaccines for generating this important immune population are lacking. Here, we report the development of a fully synthetic self-adjuvanting glycolipid-peptide conjugate vaccine designed to efficiently induce liver TRM cells. Upon cleavage in vivo, the glycolipid-peptide conjugate vaccine releases an MHC I-restricted peptide epitope (to stimulate Plasmodium-specific CD8+ T cells) and an adjuvant component, the NKT cell agonist α-galactosylceramide (α-GalCer). A single dose of this vaccine in mice induced substantial numbers of intrahepatic malaria-specific CD8+ T cells expressing canonical markers of liver TRM cells (CD69, CXCR6, and CD101), and these cells could be further increased in number upon vaccine boosting. We show that modifications to the peptide, such as addition of proteasomal-cleavage sequences or epitope-flanking sequences, or the use of alternative conjugation methods to link the peptide to the glycolipid improved liver TRM cell generation and led to the development of a vaccine able to induce sterile protection in C57BL/6 mice against Plasmodium berghei sporozoite challenge after a single dose. Furthermore, this vaccine induced endogenous liver TRM cells that were long-lived (half-life of ~425 days) and were able to maintain >90% sterile protection to day 200. Our findings describe an ideal synthetic vaccine platform for generating large numbers of liver TRM cells for effective control of liver-stage malaria and, potentially, a variety of other hepatotropic infections.

Badhai et al. describe a mouse model of mesothelioma with combined deletion of Bap1, Nf2, and Cdkn2ab that shows rapid onset and recapitulates human mesothelioma including its response to the standard treatment. This autochthonous model is well suited for testing cancer immunotherapies., We have generated mouse models of malignant mesothelioma (MM) based upon disruption of the Bap1, Nf2, and Cdkn2ab tumor suppressor loci in various combinations as also frequently observed in human MM. Inactivation of all three loci in the mesothelial lining of the thoracic cavity leads to a highly aggressive MM that recapitulates the histological features and gene expression profile observed in human patients. The tumors also show a similar inflammatory phenotype. Bap1 deletion alone does not cause MM but dramatically accelerates MM development when combined with Nf2 and Cdkn2ab (hereafter BNC) disruption. The accelerated tumor development is accompanied by increased Polycomb repression and EZH2-mediated redistribution of H3K27me3 toward promoter sites with concomitant activation of PI3K and MAPK pathways. Treatment of BNC tumor–bearing mice with cisplatin and pemetrexed, the current frontline treatment, prolongs survival. This makes the autochthonous mouse model described here very well suited to explore the pathogenesis of MM and validate new treatment regimens for MM, including immunotherapy.

Summary: Liver tissue-resident memory T (Trm) cells migrate throughout the sinusoids and are capable of protecting against malaria sporozoite challenge. To gain an understanding of liver Trm cell development, we examined various conditions for their formation. Although liver Trm cells were found in naive mice, their presence was dictated by antigen specificity and required IL-15. Liver Trm cells also formed after adoptive transfer of in vitro-activated but not naive CD8+ T cells, indicating that activation was essential but that antigen presentation within the liver was not obligatory. These Trm cells patrolled the liver sinusoids with a half-life of 36 days and occupied a large niche that could be added to sequentially without effect on subsequent Trm cell cohorts. Together, our findings indicate that liver Trm cells form as a normal consequence of CD8+ T cell activation during essentially any infection but that inflammatory and antigenic signals preferentially tailor their development. : Holz et al. demonstrate that tissue-resident memory T (Trm) cells routinely develop in the liver after T cell activation. Within the liver, IL-15, antigen, and inflammation aid Trm cell formation, but only IL-15 is essential. Newly formed Trm cells do not displace existing populations, demonstrating a flexible liver niche. Keywords: tissue-resident memory, liver, T cell memory, liver immunology, malaria, niche

Aim: To determine the prevalence of unidentified bicuspid aortic valve (BAV) or aortic dilatation (> 40 mm) in first degree relatives (FDR) of patients with isolated BAV in a general hospital. Methods and results: Patients with isolated BAV received information advising cardiac screening of their FDR. Referred and screened were 134 FDR of 54 adult index patients with isolated BAV (median 2 per index patient). FDR's mean age was 49 years (range 16-83 years) and 41% were male. They comprised 5 parents (3.7%), 52 siblings (39%) and 77 offspring (57%). Among these FDR, the prevalence of BAV was 6.0% (8 patients). In FDR without BAV, 10 (7.5%) had aortic dilatation. 'Familial BAV' was present in 9/54 families (17%). Conclusion: In a general hospital, screening of FDR of patients with isolated BAV resulted in a substantial yield of 13% new cases with BAV or aortic dilatation without BAV. (c) 2017 Elsevier B.V. All rights reserved

Background Recently, we established that First-line infliximab (FL-IFX) was superior to conventional treatment (CONV) in achieving and maintaining clinical remission in newly diagnosed paediatric patients with moderate-to-severe Crohn’s disease (CD) (PMID: 33384335). Selection of patients eligible for FL-IFX can be corroborated by combining clinical criteria with immunological biomarkers relating to the patients’ underlying immunopathology. Therefore, we investigated differential effects of FL-IFX and CONV induction treatment on serum inflammatory protein concentrations and assessed whether stratification of CD patients according to baseline serum profiles of IFX-modulated proteins relates to maintaining remission at week 52. Methods In the TISKIDS randomised controlled trial, newly diagnosed therapy-naïve CD patients with a weighted paediatric CD activity index (wPCDAI) >40 were included. FL-IFX consisted of 5 IFX infusions (5 mg/kg) combined with azathioprine (AZA) maintenance treatment. CONV treatment consisted of induction therapy with Exclusive Enteral Nutrition or oral prednisolone combined with AZA maintenance. Serum samples of 48 FL-IFX and 43 CONV patients, collected at time of diagnosis and after 10–14 weeks of induction treatment, were available. Concentrations of 92 inflammatory proteins were determined with Olink Proteomics® proximity extension technology. Hierarchical clustering was performed to stratify patients according to their serum immune profiles. Clinical disease remission was defined as wPCDAI Results At baseline, prior to therapy, clinical disease characteristics and serum inflammatory protein concentrations did not significantly differ between FL-IFX and CONV treated patients. After 10–14 weeks, FL-IFX reduced 28 proteins and enhanced 2 proteins while CONV treatment reduced 13 proteins and enhanced 1 protein. Eighteen proteins were differentially regulated by FL-IFX only. Hierarchical clustering of patients based on their baseline profiles of the 30 IFX-modulated proteins revealed 2 patient clusters. The CD-hi cluster had an increased abundance of 24/30 proteins amongst which Oncostatin-M, TNFSF14, HGF and TGF-alpha and higher clinical inflammatory parameters compared to the CD-lo cluster. Crucially, both baseline inflammatory protein profile and type of induction therapy significantly determined whether patients reached clinical disease remission without treatment escalation at week 52; with CD-hi patients having the lowest change. Conclusion FL-IFX achieves stronger reduction and modulates more proteins than CONV treatment. Stratification of patients according to profiles of IFX-modulated proteins discerns patients with a lower chance of reaching clinical remission without treatment escalation at week 52.

We describe an MHC class II (I-Ab)–restricted TCR transgenic mouse line that produces CD4+ T cells specific for Plasmodium species. This line, termed PbT-II, was derived from a CD4+ T cell hybridoma generated to blood-stage Plasmodium berghei ANKA (PbA). PbT-II cells responded to all Plasmodium species and stages tested so far, including rodent (PbA, P. berghei NK65, Plasmodium chabaudi AS, and Plasmodium yoelii 17XNL) and human (Plasmodium falciparum) blood-stage parasites as well as irradiated PbA sporozoites. PbT-II cells can provide help for generation of Ab to P. chabaudi infection and can control this otherwise lethal infection in CD40L-deficient mice. PbT-II cells can also provide help for development of CD8+ T cell–mediated experimental cerebral malaria (ECM) during PbA infection. Using PbT-II CD4+ T cells and the previously described PbT-I CD8+ T cells, we determined the dendritic cell (DC) subsets responsible for immunity to PbA blood-stage infection. CD8+ DC (a subset of XCR1+ DC) were the major APC responsible for activation of both T cell subsets, although other DC also contributed to CD4+ T cell responses. Depletion of CD8+ DC at the beginning of infection prevented ECM development and impaired both Th1 and follicular Th cell responses; in contrast, late depletion did not affect ECM. This study describes a novel and versatile tool for examining CD4+ T cell immunity during malaria and provides evidence that CD4+ T cell help, acting via CD40L signaling, can promote immunity or pathology to blood-stage malaria largely through Ag presentation by CD8+ DC.

Antibodies directed to tumour necrosis factor-α (TNF-α) are very effective in treating paediatric Crohn’s disease (CD). Over the last few years, research has provided important new insights into how to optimise this treatment’s effectiveness. Research on predictors for anti-TNF treatment responsiveness has revealed potential markers, but data on their accuracy in paediatric CD patients are lagging behind. Also, new evidence has become available on the safety profile of anti-TNF antibodies that suggests the assumed increased malignancy risk seen in patients on anti-TNF and thiopurine combination treatment may be linked more to thiopurine use and not to anti-TNF treatment. In addition, the early results of CT-P13, an infliximab biosimilar, in CD patients confirm the expected similarity with its originator. Thus, the effectiveness of anti-TNF antibody treatment is slowly improving, its malignancy risk is lower than assumed, and its costs are reduced by the introduction of equally effective biosimilars. Together, these trends allow for a more prominent role for anti-TNF antibodies in future treatment of paediatric CD.

Liver resident-memory CD8

Liver-resident memory CD8

Background In multicellular organisms, alternative splicing is central to tissue differentiation and identity. Unicellular protists lack multicellular tissue but differentiate into variable cell types during their life cycles. The role of alternative splicing in transitions between cell types and establishing cellular identity is currently unknown in any unicellular organism. Results To test whether alternative splicing in unicellular protists plays a role in cellular differentiation, we conduct RNA-seq to compare splicing in female and male sexual stages to asexual intraerythrocytic stages in the rodent malaria parasite Plasmodium berghei. We find extensive changes in alternative splicing between stages and a role for alternative splicing in sexual differentiation. Previously, general gametocyte differentiation was shown to be modulated by specific transcription factors. Here, we show that alternative splicing establishes a subsequent layer of regulation, controlling genes relating to consequent sex-specific differentiation of gametocytes. Conclusions We demonstrate that alternative splicing is reprogrammed during cellular differentiation of a unicellular protist. Disruption of an alternative splicing factor, PbSR-MG, perturbs sex-specific alternative splicing and decreases the ability of the parasites to differentiate into male gametes and oocysts, thereby reducing transmission between vertebrate and insect hosts. Our results reveal alternative splicing as an integral, stage-specific phenomenon in these protists and as a regulator of cellular differentiation that arose early in eukaryotic evolution. Electronic supplementary material The online version of this article (10.1186/s13059-019-1756-6) contains supplementary material, which is available to authorized users.