Efficient formation and maintenance of humoral and CD4 T-cell immunity targeting the viral capsid in acute-resolving hepatitis E infection

BACKGROUND & AIMS

CD4 T cells shape the neutralizing antibody (nAb) response and facilitate viral clearance in various infections. Knowledge of their phenotype, specificity and dynamics in hepatitis E virus (HEV) infection is limited. HEV is enterically transmitted as a naked virus (nHEV) but acquires a host-derived quasi-envelope (eHEV) when budding from cells. While nHEV is composed of the open reading frame (ORF)-2-derived capsid, eHEV particles also contain ORF3-derived proteins. We aimed to longitudinally characterize the HEV-specific CD4 T cells targeting ORF1, 2 and 3 and antibodies against nHEV or eHEV in immunocompetent individuals with acute and resolved HEV infection.

METHODS

HEV-specific CD4 T cells were analyzed by intracellular cytokine staining after stimulation with in silico-predicted ORF1- and ORF2-derived epitopes and overlapping peptides spanning the ORF3 region. Ex vivo multiparametric characterization of capsid-specific CD4 T cells was performed using customized MHC class II tetramers. Total and neutralizing antibodies targeting nHEV or eHEV particles were determined.

RESULTS

HEV-specific CD4 T-cell frequencies and antibody titers are highest in individuals with acute infection and decline in a time-dependent process with an antigen hierarchy. HEV-specific CD4 T cells strongly target the ORF2-derived capsid and ORF3-specific CD4 T cells are hardly detectable. NAbs targeting nHEV are found in high titers while eHEV particles are less efficiently neutralized. Capsid-specific CD4 T cells undergo memory formation and stepwise contraction, accompanied by dynamic phenotypical and transcriptional changes over time.

CONCLUSION

The viral capsid is the main target of HEV-specific CD4 T cells and antibodies in acute-resolving infection, correlating with efficient neutralization of nHEV. Capsid-specific immunity rapidly emerges followed by a stepwise contraction several years after infection.

IMPACT AND IMPLICATIONS

The interplay of CD4 T cells and neutralizing antibody responses is critical in the host defense against viral infections, yet little is known about their characteristics in hepatitis E virus (HEV) infection. We conducted a longitudinal study of immunocompetent individuals with acute and resolved HEV infection to understand the characteristics of HEV-specific CD4 T cells and neutralizing antibodies targeting different viral proteins and particles. We found that HEV-specific CD4 T cells mainly target capsid-derived epitopes. This correlates with efficient neutralization of naked virions while quasi-enveloped particles are less susceptible to neutralization. As individuals with pre-existing liver disease and immunocompromised individuals are at risk for fulminant or chronic courses of HEV infection, these individuals might benefit from the development of vaccination strategies which require a detailed knowledge of the composition and longevity of HEV-specific CD4 T-cell and antibody immunity.

Phenyl bioisosteres in medicinal chemistry: discovery of novel γ-secretase modulators as a potential treatment for Alzheimer's disease

Phenyl rings are one of the most prevalent structural moieties in active pharmaceutical ingredients, even if they often contribute to poor physico-chemical properties. Herein, we propose the use of a bridged piperidine (BP) moiety as a phenyl bioisostere, which could also be seen as a superior phenyl alternative as it led to strongly improved drug like properties, in terms of solubility and lipophilicity. Additionally, this BP moiety compares favorably to the recently reported saturated phenyl bioisosteres. We applied this concept to our γ-secretase modulator (GSM) project for the potential treatment of Alzheimer's disease delivering clinical candidates.

PFOS dominates PFAS composition in ambient fine particulate matter (PM2.5) collected across North Carolina nearly 20 years after the end of its US production

Contamination of drinking water by per- and polyfluoroalkyl substances (PFASs) emitted from manufacturing plants, fire-fighting foams, and urban waste streams has received considerable attention due to concerns over toxicity and environmental persistence; however, PFASs in ambient air remain poorly understood, especially in the United States (US). We measured PFAS concentrations in ambient fine particulate matter (PM_2.5) at 5 locations across North Carolina over a 1 year period in 2019. Thirty-four PFASs, including perfluoroalkyl carboxylic, perfluoroalkane sulfonic, perfluoroalkyl ether carboxylic and sulfonic acids were analyzed by UHPLC/ESI-MS/MS. Quarterly averaged concentrations ranged from <0.004-14.1 pg m^-3. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) ranged from <0.18 to 14.1 pg m^-3, comparable to previous PM_2.5 measurements from Canada and Europe (<0.02-3.5 pg m^-3). Concentrations above 1 pg m^-3 were observed in July-September at Charlotte (14.1 pg m^-3, PFOA), Wilmington (4.75 pg m^-3, PFOS), and Research Triangle Park (1.37 pg m^-3, PFOS). Notably, PM_2.5 has a short atmospheric lifetime (<2 weeks), and thus, the presence of PFOS in these samples raises questions about their sources, since PFOS production was phased out in the US ∼20 years ago. This is the first US study to provide insights into ambient PFAS concentrations in PM_2.5.

Autoantibodies against zinc transporter 8 further stratify the autoantibody-defined risk for type 1 diabetes in a general population of schoolchildren and have distinctive isoform binding patterns in different forms of autoimmune diabetes: results from the Karlsburg Type 1 Diabetes Risk Study

AIMS

To evaluate the diagnostic relevance of autoantibodies against zinc transporter 8 (ZnT8) in schoolchildren from the general population as well as in people with autoimmune diabetes.

METHODS

A total of 137 schoolchildren positive for at least one of the three major diabetes-associated autoantibodies, without diabetes heredity or preselection on HLA typing, from the Karlsburg Type 1 Diabetes Risk Study, as well as 102 people at type 1 diabetes onset, 88 people with latent autoimmune diabetes in adults and 119 people with type 2 diabetes, were analysed for different ZnT8 autoantibody variants.

RESULTS

Zinc transporter 8 autoantibody positivity was found in 18% of autoantibody-positive schoolchildren, with a noticeable association with other autoantibodies associated with type 1 diabetes and disease progression. Furthermore, ZnT8 autoantibody positivity was associated with diabetes progression in schoolchildren positive for autoantibodies against insulinoma-associated antigen-2 (IA-2) and, importantly, in seven IA-2 autoantibody-negative schoolchildren. Additionally, ZnT8 autoantibodies were found in 56% of people with type 1 diabetes, predominantly directed against all three ZnT8 variants and comparable to schoolchildren with multiple autoantibodies. In contrast, ZnT8 autoantibodies were detected in 10% of people with latent autoimmune diabetes in adults, none of them with reactivity to all three isoforms.

CONCLUSION

Zinc transporter 8 autoantibodies are useful markers for prediction of type 1 diabetes in a general population, further stratifying the risk of progression in autoantibody-positive children. ZnT8 autoantibodies are also important markers in adult-onset diabetes, with a completely different reaction pattern in type 1 diabetes in comparison to latent autoimmune diabetes in adults, and may therefore help to differentiate between the two forms.

Penetrance and predictive value of genetic screening in acute porphyria

OBJECTIVE

Penetrance, predictive value and female patients' perspectives on genetic testing were evaluated among Finnish patients with acute porphyria. We conducted a retrospective study to evaluate prognosis among at-risk female family members depending on the primary method of diagnosis.

METHODS

The penetrance was calculated among 23 genetically heterogeneous families selected from the Finnish porphyria registry (n = 515, AIP 333; VP 182). We included kindreds with ≥9 patients in a family (range 9-23 patients, total 216 AIP; 129 VP). In 2015, the registry included 164 living female subjects between 14 and 85 years of age. A questionnaire was sent to 143 women, of whom 107 (75%, AIP 67; VP 40) replied. Female at-risk relatives (AIP 54; VP 30) were divided into two groups based on the primary method of diagnosis: mutation analysis (Group A, n = 40) or biochemical analysis (Group B, n = 44).

RESULTS

Mean penetrance for all acute symptoms was 35% among AIP and 40% among VP families. In both study groups, the penetrance was higher among female (AIP 50%; VP 44%) than male patients (AIP 17%; VP 33%). Penetrance for hospitalized attacks was 30% among AIP families (range 10-80%, for women 41%) and 25% in VP (range 0-50%, for women 27%) demonstrating wide variations among families even with the similar genotype. Acute porphyria was diagnosed at the median age of 26 years (range 0-76 years) among female patients, commonly after the onset of acute symptoms. Diagnostic delay was an average of 7.4 years (range 1-30 years). Acute symptoms occurred at the median age of 24 years (range 10-57 years) and the first hospitalization at the median age of 26.5 years (range 15-57 years). At the onset of symptoms, 38% of the women were ≤ 20 years of age. According to the life table analysis, acute attacks occurred mainly during the following five years after the diagnosis and the attack risk diminished after 35 years of age. The annual risk for hospitalization due to an acute attack during fertile years was lower in Group A than Group B (0.002 vs. 0.010, p = .018), but the risk of all subsequent acute symptoms did not diminish (Group A 0.017 vs. Group B 0.019, p = .640). The cumulative risk of acute symptoms among asymptomatic patients at the time of diagnosis was 26.7% for Group A and 58.3% for Group B. The cumulative risk of the first subsequent attack requiring hospitalization after the diagnosis among all at-risk relatives was similarly less frequent in Group A than in Group B (OR 0.180; 95% CI 0.041-0.789, p = .041). If attacks were followed among symptomatic patients only, attack-free years were more frequent in Group A than in Group B. Patients preferred genetic screening before puberty to minimize the risk of acute symptoms and genetic discrimination was rare. 44% of the patients reported social, psychological or physical impairment due to acute hepatic porphyria, emphasizing the importance of supporting patients' emotional and resilience capacity.

CONCLUSIONS

Among female at-risk relatives the annual risk for hospitalization due to an acute attack is <1% and for acute symptoms <2% during the fertile years. Genetic testing of relatives diminishes the risk of acute attacks. Diagnosis before symptom onset is key for subjects to remain asymptomatic during follow-up, and genetic screening should be done earlier than currently.

Quality-of-life analysis of the MITO-8, MaNGO, BGOG-Ov1, AGO-Ovar2.16, ENGOT-Ov1, GCIG study comparing platinum-based versus non-platinum-based chemotherapy in patients with partially platinum-sensitive recurrent ovarian cancer

Background

MITO-8 showed that prolonging platinum-free interval by introducing non-platinum-based chemotherapy (NPBC) does not improve prognosis of patients with partially platinum-sensitive recurrent ovarian cancer. Quality of life (QoL) was a secondary outcome.

Patients and methods

Ovarian cancer patients recurring or progressing 6-12 months after previous platinum-based chemotherapy (PBC) were randomized to receive PBC or NPBC as first treatment. QoL was assessed at baseline, third and sixth cycles, with the EORTC C-30 and OV-28 questionnaires. Mean changes and best response were analysed. Progression-free survival, response rate, and toxicity are also reported for proper interpretation of data. All analyses were based on intention-to-treat.

Results

Out of the 215 patients, 151 (70.2%) completed baseline questionnaire, balanced between the arms; thereafter, missing rate was higher in the NPBC arm. At mean change analysis, C30 scores were prevalently worse in the NPBC than PBC arm, statistical significance being attained for emotional functioning, global health status/QoL, fatigue, and dyspnoea (effect sizes ranging from 0.30 to 0.51). Conversely, as for OV28 scale, the other chemotherapy side-effects item was significantly worse with PBC at three and six cycles, with a larger effect size (0.70 and 0.54, respectively). At best response analysis, improvement of emotional functioning and pain and worsening of peripheral neuropathy and other chemotherapy side-effects were significantly more frequent in the PBC arm. Progression-free survival (median 9 versus 5 months, P = 0.001) and objective response rate (51.6% versus 19.4%, P = 0.0001) were significantly better with PBC. Allergy, blood cell count, alopecia, nausea, musculoskeletal, and neurological side-effects were more frequent and severe with PBC; hand-foot skin reaction, rash/desquamation, mucositis, and vascular events were more frequent with NPBC.

Conclusion

MITO-8 QoL analysis shows that deterioration of some functioning and symptom scales is lower with PBC, with improvement of emotional functioning and pain, despite worsening of toxicity-related items.

ClinicalTrials.gov

NCT00657878.

Advantage of proton-radiotherapy for pediatric patients and adolescents with Hodgkin's disease

Abstract

Radiotherapy is frequently used in the therapy of lymphoma. Since lymphoma, for example Hodgkin’s disease, frequently affect rather young patients, the induction of secondary cancer or other long-term adverse effects after irradiation are important issues to deal with. Especially for mediastinal manifestations numerous organs and substructures at risk play a role. The heart, its coronary vessels and cardiac valves, the lungs, the thyroid and, for female patients, the breast tissue are only the most important organs at risk. In this study we investigated if proton-radiotherapy might reduce the dose delivered to the organs at risk and thus minimize the therapy-associated toxicity.

Methods

In this work we compared the dose delivered to the heart, its coronary vessels and valves, the lungs, the thyroid gland and the breast tissue by different volumetric photon plans and a proton plan, all calculated for a dose of 28.8 Gy (EURO-NET-PHL-C2). Target Volumes have been defined by F18-FDG PET-positive areas, following a modified involved node approach. Data from ten young female patients with mediastinal lymphoma have been evaluated. Three different modern volumetric IMRT (VMAT) photon plans have been benchmarked against each other and against proton-irradiation concepts. For plan-evaluation conformity- and homogeneity-indices have been calculated as suggested in ICRU 83. The target volume coverage as well as the dose to important organs at risk as the heart with its substructures, the lungs, the breast tissue, the thyroid and the spinal cord were calculated and compared. For statistical evaluation mean doses to organs at risk were evaluated by non- parametric Kruskal-Wallis calculations with pairwise comparisons.

Results

Proton-plans and three different volumetric photon-plans have been calculated. Proton irradiation results in significant lower doses delivered to organ at risk. The median doses and the mean doses could be decreased while PTV coverage is comparable. As well conformity as homogeneity are slightly better for proton plans. For several organs a risk reduction for secondary malignancies has been calculated using literature data as reference.

According to the used data derived from literature especially the secondary breast cancer risk, the secondary lung cancer risk and the risk for ischemic cardiac insults can be reduced significantly by using protons for radiotherapy of mediastinal lymphomas.

Conclusion

Irradiation with protons for mediastinal Hodgkin-lymphoma results in significant lower doses for almost all organs at risk and is suitable to reduce long term side effects for pediatric and adolescent patients.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1360-7) contains supplementary material, which is available to authorized users.

Abstract P4-08-34: MammaTyper© – An in vitro quantitative local gene expression test as a predictor of OncotypeDX©- and EndoPredict©-results

Background:

Risk stratification in early-stage breast cancer patients still remains a clinical challenge. It is well known that expression of ER/ PR, HER2 and Ki-67 are valuable prognostic and predictive markers. According to the commonly used St. Gallen classification (2013), breast cancer treatment decisions can be based on four different subtypes (Luminal A-like, Luminal B-like [HER2+/-], HER2 + [non-luminal] and Basal-like).

Immunohistochemistry is predominantly used to determine the receptor status, although semi-quantitative analysis shows significant inter-observer variability.

Several quantitative gene expression tests – such as Oncotype DX© and EndoPredict© – are available as diagnostic tools but their use is often limited due to financial considerations.

MammaTyper© has been shown to be a precise and reproducible biomarker determination tool to investigate the expression of ER/ PR, HER2 and Ki-67 and may prove to be a cost efficient quantitative diagnostic tool.

Methods:

This study tested ESR-1, PGR, MKI67 and ERBB2 mRNA-levels by RT-qPCR in 100 FFPT-samples using MammaTyper© kit. The test identified breast cancer subgroups according to St. Gallen classification. RT-qPCR results were correlated to IHC-test results via χ2-Test and to risk groups of Oncotype DX©- (n=55) and EndoPredict©-testing (n=45). Oncotype©-Recurrence Score levels were separated into low (RS &lt;18), intermediate (RS 18-30) and high risk (RS ≥ 31). EndoPredict© EPScore© and EPclin Risk Score© cut off levels defining high and low risk levels were 7.0, respectively 3.3. Linear regression model was performed investigating the prediction of EPscore© and Recurrence Score© via MammaTyper© mRNA-results.

Results:

IHC-testing resulted in 43 Luminal A-like samples (43%) and 57 Luminal B-like [HER2 negative] (57%) tumors. MammaTyper ©-based classification showed significant correlation to IHC-based classification (χ2=12,68; p=0,005).

EndoPredict©-data showed low-risk levels in 36 patients (80%) and high-risk status in 9 cases (20%). Correlation to mRNA-based St. Gallen-subtypes approved significance (χ2=17,32, p&lt;0,001). In linear regression model only MKI67-mRNA showed independent correlation to EPScore© (p&lt;0,001; R2 0,290)

A total of 34 patients (61,8%) showed low risk, 13 (26,3%) intermediate risk (RS 18-30) and 8 (14,5%) high-risk recurrence score levels (RS≥31) in OncotypeDX©. MammaTyper© results correlated to OncotypeDX© risk-levels (χ2=27,98; p&lt;0,001). In linear regression model mRNA-levels of ESR-1, PGR and MKI67 were significant predictors of OncotypeDX© RS (p-values: p=0,003, p&lt;0,001, p=0,033, R2= 0,602)

Conclusion:

This study shows mRNA-testing is a valid marker to identify breast cancer subtypes. Additionally, MammaTyper© results are significantly correlated to Oncotype DX©- and EndoPredict©-results, indicating it might be an efficient as well as cost effective diagnostic instrument. However a large prospective multicenter study should be performed to prove its diagnostic validity in predicting the most appropriate and effective treatment in early-stage breast cancer.

Citation Format: Eckhoff K, Pokorny J, Baumann K, Perner S, Pursche T, Rody A. MammaTyper© – An in vitro quantitative local gene expression test as a predictor of OncotypeDX©- and EndoPredict©-results [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-34.

[Differential diagnosis of dissociative seizures]

Patient history taking and semiology provide seminal clues to the diagnosis of dissociative seizures. Openness and alertness of the treating physician are essential. Video-electroencephalogram(EEG)-based analyses of the events are crucial to establish the correct diagnosis, particularly in complex cases. The patient-doctor relationship is of particular importance in order to successfully motivate the patient for psychotherapeutic treatment. Coexisting psychiatric morbidity as well as other functional somatic symptoms must be actively explored. Current changes in the established diagnostic manuals, including ICD-11, reflect the ongoing vivid interest and controversial discussions in the field of dissociative disorders.