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Taenia solium cysticercosis and taeniasis (TSCT), caused by the tapeworm T. solium, is a foodborne and zoonotic disease classified since 2010 by WHO as a neglected tropical isease. It causes considerable impact on health and economy and is one of the leading causes of acquired epilepsy in most endemic countries of Latin America, Sub-Saharan Africa, and Asia. There is some evidence that the prevalence of TSCT in high-income countries has recently increased, mainly due to immigration from endemic areas. In regions endemic for TSCT, human cysticercosis can manifest clinically as neurocysticercosis (NCC), resulting in epileptic seizures and severe progressive headaches, amongst other neurological signs and/or symptoms. The development of these symptoms results from a complex interplay between anatomical cyst localization, environmental factors, parasite's infective potential, host genetics, and, especially, host immune responses. Treatment of individuals with active NCC (presence of viable cerebral cysts) with anthelmintic drugs together with steroids is usually effective and, in the majority, reduces the number and/or size of cerebral lesions as well as the neurological symptoms. However, in some cases, treatment may profoundly enhance anthelmintic inflammatory responses with ensuing symptoms, which, otherwise, would have remained silent as long as the cysts are viable. This intriguing silencing process is not yet fully understood but may involve active modulation of host responses by cyst-derived immunomodulatory components released directly into the surrounding brain tissue or by the induction of regulatory networks including regulatory T cells (Treg) or regulatory B cells (Breg). These processes might be disturbed once the cysts undergo treatment-induced apoptosis and necrosis or in a coinfection setting such as HIV. Herein, we review the current literature regarding the immunology and pathogenesis of NCC with a highlight on the mobilization of immune cells during human NCC and their interaction with viable and degenerating cysticerci. Moreover, the immunological parameters associated with NCC in people living with HIV/AIDS and treatments are discussed. Eventually, we propose open questions to understand the role of the immune system and its impact in this intriguing host-parasite crosstalk.

Manual blood smear analysis remains the gold standard to diagnose hematological disorders and infections of blood parasites. However, the analysis and interpretation of peripheral blood smears requires expert users, is time consuming, depends on inter-observer variation, and is not compatible with a high-throughput workflow for clinical routine diagnostics (Dunning & Safo, Biotech. Histochem. 2011, 86, 69–75; Pierre, Clin. Lab. Med., 2002, 22, 279–297). Instead, automated hematology analyzers only flag atypical results which provides no clear classification of diseases and require extensive sample preparation. Label-free image analysis of untouched blood cells would reduce pre-analytical efforts and potentially allows characterization of samples with higher information content compared to both smear analysis and conventional automated flow cytometry, as the blood cell morphology is preserved. Furthermore, preclinical research work is in need for non-invasive analysis of e.g. cancer cells or infected cells to support the discovery of new drugs. We suggest to apply high-throughput and label-free workflows based on digital holographic microscopy for standardizable image analysis relevant for pre- and clinical diagnosis. In the case of parasitic infections, the label-free detection and analysis of malaria parasites has been addressed by various studies (Anand et al., IEEE Photonics J., 2012, 4, 1456-1464; Seo et al., Appl. Phys. Lett., 2014, 104, 1-4; Park et al, PloS One, 2016, 11, 1-19; Ugele et al., Lab Chip, 2018, 18, 1704-1712). The detection of neglected tropical diseases affecting livestock and humans, such as Chagas disease and Leishmaniosis, has not been addressed so far by the community. Our platform technology is based on a customized differential holographic microscopy setup, which has been previously described (Ugele et al., Lab Chip, 2018, 18, 1704-1712; Ugele et al., Adv. Sci., 2018, 5, 1800761). Reference data sets of clinical leukemic samples, cancer cell cultures in solution, and in vitro cultures of various parasites were collected to understand the translational potential for this methodology. Hydrodynamic and viscoelastic focusing in a microfluidics channel was used for high-throughput imaging and enrichment/depletion of cell populations without the need for any autofocusing procedures. Morphological parameters describing the inner consistency were calculated from segmented phase images of the cells/parasites and combined with machine learning algorithms for improved analysis by the discovery of label-free biomarkers. In this way, improved subtyping of acute and chronic leukemias, myeloproliferative neoplasms, and further hematological disorders was achieved. Second, a detection of Trypanosoma and Leishmania parasites could be shown and in vitro cultures of Schistosomia mansoni were classified according to different viability stages. Third, the capability of anti-cancer drug candidate screening was demonstrated by monitoring the mesenchymal-epithelial transition of pancreas cancer cell cultures. We envision, that our platform technology has the potential as a cost-efficient method for automated diagnosis of various hematological disorders, parasitic infections, drug screening and monitoring of therapy efficacy. With further integration effort we also believe that the technology can be applied in resource limited settings.