The Truman Show for Human Helminthic Parasites: A Review of Recent Advances in In Vitro Cultivation Platforms.

Throughout history, parasites and parasitic diseases have been humankind's constant companions, as evidenced by the findings of tapeworm eggs in ancient, mummified remains. Helminths are responsible for causing severe, long-term, and debilitating infectious diseases worldwide, especially affecting economically challenged nations due to prevailing deficits in access to sanitation, proper hygiene practices, and healthcare infrastructure. Socio-ecological drivers, such as poverty, migration, and climate change, continue to contribute to parasites and their disease vectors being spread beyond known endemic zones. The study of parasitic diseases has had a fair amount of success leading to the development of new chemotherapeutic agents and the implementation of parasite eradication programs. However, further progress in this direction has been hampered by the challenges of culturing some of these parasites in in vitro systems for efficient availability, basic life cycle, infection studies, and effectiveness of novel treatment strategies. The complexity of the existing models varies widely, depending on the parasite and its life cycle, ranging from basic culture methods to advanced 3D systems. This review aims to highlight the research conducted so far in culturing and maintaining parasites in an in vitro setting, thereby contributing to a better understanding of pathogenicity and generating new insights into their lifecycles in the hopes of leading to effective treatments and prevention strategies. This work is the first comprehensive outline of existing in vitro models for highly transmissible helminth diseases causing severe morbidity and mortality in humans globally.

Coronavirus-mimicking nanoparticles (CorNPs) in artificial saliva droplets and nanoaerosols: Influence of shape and environmental factors on particokinetics/particle aerodynamics.

Severe acute respiratory syndrome coronavirus 2, abbreviated as SARS-CoV-2, has been associated with the transmission of infectious COVID-19 disease through breathing and speech droplets emitted by infected carriers including asymptomatic cases. As part of SARS-CoV-2 global pandemic preparedness, we studied the transmission of aerosolized air mimicking the infected person releasing speech aerosol with droplets containing CorNPs using a vibrating mesh nebulizer as human patient simulator. Generally speech produces nanoaerosols with droplets of <5 µm in diameter that can travel distances longer than 1 m after release. It is assumed that speech aerosol droplets are a main element of the current Corona virus pandemic, unlike droplets larger than 5 m, which settle down within a 1 m radius. There are no systemic studies, which take into account speech-generated aerosol/droplet experimental validation and their aerodynamics/particle kinetics analysis. In this study, we cover these topics and explore role of residual water in aerosol droplet stability by exploring drying dynamics. Furthermore, a candle experiment was designed to determine whether air pollution might influence respiratory virus like nanoparticle transmission and air stability.

The Truman Show for protozoan parasites: A review of in vitro cultivation platforms.

Protozoan parasites are responsible for severe disease and suffering in humans worldwide. Apart from disease transmission via insect vectors and contaminated soil, food, or water, transmission may occur congenitally or by way of blood transfusion and organ transplantation. Several recent outbreaks associated with fresh produce and potable water emphasize the need for vigilance and monitoring of protozoan parasites that cause severe disease in humans globally. Apart from the tropical parasite Plasmodium spp., other protozoa causing debilitating and fatal diseases such as Trypanosoma spp. and Naegleria fowleri need to be studied in more detail. Climate change and socioeconomic issues such as migration continue to be major drivers for the spread of these neglected tropical diseases beyond endemic zones. Due to the complex life cycles of protozoa involving multiple hosts, vectors, and stringent growth conditions, studying these parasites has been challenging. While in vivo models may provide insights into host-parasite interaction, the ethical aspects of laboratory animal use and the challenge of ready availability of parasite life stages underline the need for in vitro models as valid alternatives for culturing and maintaining protozoan parasites. To our knowledge, this review is the first of its kind to highlight available in vitro models for protozoa causing highly infectious diseases. In recent years, several research efforts using new technologies such as 3D organoid and spheroid systems for protozoan parasites have been introduced that provide valuable tools to advance complex culturing models and offer new opportunities toward the advancement of parasite in vitro studies. In vitro models aid scientists and healthcare providers in gaining insights into parasite infection biology, ultimately enabling the use of novel strategies for preventing and treating these diseases.

Development of a Novel Method for Identification of Alaria alata Mesocercariae by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

Alaria (A.) alata mesocercariae (AM) have increasingly appeared as incidental findings during the mandatory inspection of wild boars for Trichinella in many European countries. An Alaria spp.-specific PCR is available for the identification of AM; however, it is time- and cost-intensive. Therefore, we propose a rapid and cost-efficient MALDI-TOF assay for the identification of AM in wild boar meat that can be applied in routine diagnostics. In this study, a fast and methodologically simple protocol for the protein extraction of AM from different host species in different countries was established, and an AM-specific reference spectra database was created as part of the ongoing development of an existing Trichinella spp. database. A formic acid protein extraction was performed after pooling 10 AM from the same host individual. In total, 61 main spectra profiles (MSPs) from different host individuals were stored in an AM-specific MSP library. The cluster analysis of these 61 MSPs indicated a possible variation within the A. alata species with a tentative association with the geographical origin of the host, but not the host species. This MALDI-TOF assay allows for a fast verification of the AM isolates, which is the next step in the development of a universal database for the identification of several parasites isolated from meat.

Prevalence of Alaria alata mesocercariae in wild boars from Brandenburg, Germany.

Since 2002, Alaria (A.) alata mesocercariae (AM) have been found during routine Trichinella inspection of wild boars in many European countries. To date, human infection with AM through consumption of undercooked or raw AM infested wild boar meat cannot be excluded. In Germany, data on the parasite's prevalence in wild boars are scarce. To better understand temporal and spatial fluctuations of this parasite, this study investigated the prevalence of AM in wild boars in the German federal state of Brandenburg during three hunting seasons from 2017 to 2020. In total, 28.3% (100/354, 95% CI: 23.3-33.3%) of all wild boars sampled in eight counties of Brandenburg were tested positive for AM by Alaria alata mesocercariae migration technique (AMT). AM were detected in wild boars from seven different counties. Samples from one county (Havelland) tested completely negative for AM (0/16). Prevalences of the seven AM positive counties of Brandenburg ranged from 11.5 (3/26, 95% CI: 2.5-30.1%) in Märkisch-Oderland to 64.1% (25/39, 95% CI: 47.2-78.8%) in Uckermark. An association between sex and A. alata positivity could not be determined. A statistically significant increase in frequency of older AM positive wild boars was observed (p = 0.001). For a nationwide assessment of the prevalence of A. alata in wild boars and the risk for consumers of ingesting viable AM by consumption of raw or undercooked AM infested wild boar meat, further long-term studies in different regions of Germany are needed.