CIMT 2023: report on the 20th Annual Meeting of the Association for Cancer Immunotherapy

The Association for Cancer Immunotherapy (CIMT) celebrated the 20th anniversary of the CIMT Annual Meeting. CIMT2023 was held 3-5 May 2023 in Mainz, Germany. 1051 academic and clinical professionals from over 30 countries attended the meeting and discussed the latest advances in cancer immunology and immunotherapy research. This report summarizes the highlights of CIMT2023.

Nosocomial influenza in south-western Swiss hospitals during two seasonal epidemics: an observational study

BACKGROUND

In Switzerland each year, influenza leads to between 112,000 and 275,000 medical consultations. Data on nosocomial influenza infection are limited.

AIM

To describe nosocomial cases of seasonal influenza in south-western Switzerland.

METHODS

This study was conducted during two seasonal influenza epidemics from 2016 to 2018 in 27 acute care public hospitals in south-western Switzerland. During these two time-periods, every patient hospitalized for >72 h who was positively screened by reverse transcription-polymerase chain reaction or antigen detection for influenza was included in the survey. Characteristics of patients included age, sex, and comorbidities. Included patients were followed up until discharge or death. Complications and administration of antineuraminidases and/or antibiotics were registered.

FINDINGS

The median influenza vaccine coverage of healthcare workers was 40%. In all, 836 patients were included (98% with type A influenza virus in 2016-2017; 77% with type B virus in 2017-2018). Most patients (81%) had an unknown vaccine status. Overall, the incidence of nosocomial influenza was 0.5 per 100 admissions (0.35 per 1000 patient-days). The most frequent comorbidities were diabetes (20%), chronic respiratory diseases (19%), and malnutrition (17%). Fever (77%) and cough (66%) were the most frequent symptoms. Seventy-one percent of patients received antineuraminidases, 28% received antibiotics. Infectious complications such as pneumonia were reported in 9%. Overall, the all-cause mortality was 6%.

CONCLUSION

The occurrence of nosocomial influenza underlines the importance of vaccinating patients and healthcare workers, rapidly recognizing community- or hospital-acquired cases, and applying adequate additional measures to prevent dissemination, including the timely administration of antineuraminidases to avoid antibiotic use (and misuse).

Optimized polyethylenimine (PEI)-based nanoparticles for siRNA delivery, analyzed in vitro and in an ex vivo tumor tissue slice culture model

The non-viral delivery of small RNA molecules like siRNAs still poses a major bottleneck for their successful application in vivo. This is particularly true with regard to crossing physiological barriers upon systemic administration. We have previously established polyethylenimine (PEI)-based complexes for therapeutic RNA formulation. These nanoplexes mediate full RNA protection against nucleolytic degradation, delivery to target tissues as well as cellular uptake, intracellular release and therapeutic efficacy in preclinical in vivo models. We herein present data on different polyplex modifications for the defined improvement of physicochemical and biological nanoparticle properties and for targeted delivery. (i) By non-covalent modifications of PEI polyplexes with phospholipid liposomes, ternary complexes ("lipopolyplexes") are obtained that combine the favorable features of PEI and lipid systems. Decreased cytotoxicity and highly efficient delivery of siRNA is achieved. Some lipopolyplexes also allow prolonged storage, thus providing formulations with higher stability. (ii) Novel tyrosine modifications of low molecular weight PEI offer further improvement of stability, biocompatibility, and knockdown efficacy of resulting nanoparticles. (iii) For ligand-mediated uptake, the shielding of surface charges is a critical requirement. This is achieved by PEI grafting with polyethylene glycol (PEG), prior to covalent coupling of anti-HER1 antibodies (Erbitux®) as ligand for targeted delivery and uptake. Beyond tumor cell culture, analyses are extended towards tumor slice cultures from tumor xenograft tissues which reflect more realistically the in vivo situation. The determination of siRNA-mediated knockdown of endogenous target genes, i.e., the oncogenic survival factor survivin and the oncogenic receptor tyrosine kinase HER2, reveals nanoparticle penetration and biological efficacy also under intact tissue and stroma conditions.

Tumor tissue slice cultures as a platform for analyzing tissue-penetration and biological activities of nanoparticles

The success of therapeutic nanoparticles depends, among others, on their ability to penetrate a tissue for actually reaching the target cells, and their efficient cellular uptake in the context of intact tissue and stroma. Various nanoparticle modifications have been implemented for altering physicochemical and biological properties. Their analysis, however, so far mainly relies on cell culture experiments which only poorly reflect the in vivo situation, or is based on in vivo experiments that are often complicated by whole-body pharmacokinetics and are rather tedious especially when analyzing larger nanoparticle sets. For the more precise analysis of nanoparticle properties at their desired site of action, efficient ex vivo systems closely mimicking in vivo tissue properties are needed. In this paper, we describe the setup of organotypic tumor tissue slice cultures for the analysis of tissue-penetrating properties and biological activities of nanoparticles. As a model system, we employ 350μm thick slice cultures from different tumor xenograft tissues, and analyze modified or non-modified polyethylenimine (PEI) complexes as well as their lipopolyplex derivatives for siRNA delivery. The described conditions for tissue slice preparation and culture ensure excellent tissue preservation for at least 14days, thus allowing for prolonged experimentation and analysis. When using fluorescently labeled siRNA for complex visualization, fluorescence microscopy of cryo-sectioned tissue slices reveals different degrees of nanoparticle tissue penetration, dependent on their surface charge. More importantly, the determination of siRNA-mediated knockdown efficacies of an endogenous target gene, the oncogenic survival factor Survivin, reveals the possibility to accurately assess biological nanoparticle activities in situ, i.e. in living cells in their original environment. Taken together, we establish tumor (xenograft) tissue slices for the accurate and facile ex vivo assessment of important biological nanoparticle properties. Beyond the quantitative analysis of nanoparticle tissue-penetration, the excellent tissue preservation and cell viability also allows for the evaluation of biological activities.

[Strongyloidiasis: who is at risk of severe infection and how to prevent it?]

Strongyloides stercoralis hyperinfection syndrome, which carries a high mortality (60%), occurs usually after immunosuppressive therapy. Cellular immunosuppression allows the parasite to reactivate and stimulate its cycle of auto-infection. It is therefore important to prevent this syndrome by screening at risk patients at risk for chronic strongyloidiasis before starting immunosuppressive treatment and especially before treatment with corticosteroids, even that of short duration. Ivermectine is the treatment of choice.

[Non-HIV infectious disease outpatient consultations: a 5-year study in a Swiss University Hospital]

Few studies have examined the workload or clinical spectrum of non-HIV infectious diseases outpatient consultations (IDOC). This retrospective study aims to describe IDOC referrals over the past 5 years. In total, 483 patients were referred (with an increase of 63% between 2009 and 2013). Most referrals were received from primary care clinicians (45%). Median patient age was 47 years, 57% of patients were men and 17% were immunosuppressed. Of the diagnoses retained, 74% were infectious, 20% were non-infectious and 6% were of unknown aetiology. Two community outbreaks were identified (tattoo-related mycobacterial infection and Q fever). In conclusion, the infectious diseases outpatient clinic, which has expanded progressively in the past 5 years, provides a specialised service for primary health clinicians and for public health.

Die Kristall- und Molekülstruktur von β -Bromo(2-diäthylaminoäthanolato)kupfer(ll) / The Crystal and Molecular Structure of β-Bromo(2-diethylaminoethanolato)copper(II)

The crystal and molecular structure of β-bromo(diethylaminoethanolato)copper(II) has been determined from three dimensional X-ray diffractometer data. The compound crystallizes in the triclinic space group Pï with one dimer in a unit cell of dimensions α=10.180(II), b=7.999(9), c=6.227(7) Å and a=110.69(4), β=103.12(4), γ=73.82(4)[°]. The structure was refined by least-squares methods using 1944 independent reflexions to give a final R-index of 0,05. The molecule consists of dimeric Cu2O2-units with Cu—O distances of 1.900(4) Å and 1.914(4) A, respectively. The dimers are additional bridged by bromines, so that a “polymeric” structure results; Cu—Br distances are 2.357(2) and 3.660(2) A, respectively. The Cu—Cu distances are 3.003(2) (oxygen bridges) and 4.506(2) Å (bromine bridges).

Different Temperature Dependence of Magnetic Susceptibility of Different Molecular Complexes of Copper (II) with 7-Hydroxy-4-methyl-5-aza-hept-4-en-2-on

Two principally different molecular structures in the crystalline state are known from the copper (II) complex with 7-hydroxy-4-methyl-5-aza-hept-4-en-2-on. The magnetic susceptibilities of three forms of this compound [α-(CuEIA)4, β-(CuEIA)4, and β-(CuEIA)4·2 C6H6] have been measured in the temperature range 2.6-300 K. The results indicate that principally different molecular structures correspond to principally different magnetic properties. While the α-form shows antiferromagnetic spin coupling in the S′ = 0 ground state, the electrons in the β-form are coupled ferromagnetically in the S′ = 2 ground state. A fitting procedure of a theoretical equation based on the isotropic HDVV-model led to a satisfactory agreement between calculated and experimental data for α-(CuEIA)4 and β-(CuEIA)4 , while this was not possible for β-(CuEIA)4·2C6H6 . The exchange parameters obtained for α-(CuEIA)4 (g=2.13, J12= -17cm-1, J13=+3.5cm-1, and Na=60-10-8 cgs-emu) are in good agreement with the values given by Ginsberg et al. For β-(CuEIA)4 a weak antiferromagnetic intercluster interaction could be determined at low tempera­tures. The fitting procedure yielded the following values: g=2.05, J12=-6.4 cm-1, J13=+24.2 cm-1, Na=10·10-6 cgs-emu, ⊖=-0.27°.

[Breast infections]

Breast infections such as mastitis and breast abscesses are frequent. They are usually caused by the same microorganisms as those that cause other soft tissue infections. For a simple mastitis, a treatment with antibiotics alone is usually sufficient, whereas drainage is necessary when an abscess is present. While ultrasound-assisted puncture and aspiration is the best approach for breast abscesses of less than 3 cm, surgery is recommended for more extended infection. Infections of breast implants have to be treated applying a mixed surgical-medical approach with removal of the implant (usually in one stage exchange) and antibiotics adapted to the microorganism identified.

[Hospital-based internal medicine: year 2011 in chief resident's perspective]

The year 2011 was full of significant advances in all areas of medicine. Whether small or large issues, they all have an impact on daily practice in general internal medicine. For example, intravenous administration of diuretics in heart failure shows no benefit. But double dose may improve symptoms faster. Direct Xa inhibitors are emerging as alternative to anti-vitamin K. beta-blockers reduce overall mortality in COPD and do not worsen lung function significantly. Each year, the chief residents from the Department of internal medicine at the University hospital of Lausanne meet to share their readings. Twelve new therapeutic considerations of 2011 are reviewed here.

Does the Distribution of Fixation Times Refer to the Underlying Process of Information Input?

Two experiments were conducted to assess whether the distribution of fixation times might be related to the prevailing cognitive activity involved with two different tasks, i.e., driving and observing colored fields. The results suggest that the distribution of fixation times can be associated with the prevailing cognitive activity while viewing.