Aberrant glycosylation plays a crucial role in tumour progression and invasiveness. Tumour-associated carbohydrate antigens (TACAs) represent a valuable set of targets for immunotherapeutic approaches. The poor immunogenicity of glycan structures, however, requires a more effective and well-directed way of targeting TACAs on the surface of cancer cells than antibodies. The glycosphingolipid globotriaosylceramide (Gb3) is a well-established TACA present in a multitude of cancer types. Its overexpression has been linked to metastasis, invasiveness, and multidrug resistance. In the present study, we propose to use a dimeric fragment of the Shiga toxin B-subunit (StxB) to selectively target Gb3-positive cancer cells in a StxB-scFv UCHT1 lectibody. The lectibody, comprised of a lectin and the UCHT1 antibody fragment, was produced in E. coli and purified via Ni-NTA affinity chromatography. Specificity of the lectibody towards Gb3-positive cancer cell lines and specificity towards the CD3 receptor on T cells, was assessed using flow cytometry. We evaluated the efficacy of the lectibody in redirecting T cell cytotoxicity towards Gb3-overexpressing cancer cells in luciferase-based cytotoxicity in vitro assays. The StxB-scFv UCHT1 lectibody has proven specific for Gb3 and could induce the killing of up to 80% of Gb3-overexpressing cancer cells in haemorrhagic and solid tumours. The lectibody developed in this study, therefore, highlights the potential that lectibodies and lectins in general have for usage in immunotherapeutic approaches to boost the efficacy of established cancer treatments.

Background: Mechanical stretch of the myocardium is proarrhythmic and alters cellular Ca ²⁺ handling, potentially involving cation nonselective mechano‐sensitive ion channels. This study aimed to assess the presence and mechanisms of stretch‐induced increase in Ca ²⁺ ‐spark rate (SiS) in isolated atrial cardiomyocytes. Methods: Freshly isolated rabbit, pig, and human left atrial cardiomyocytes were stretched axially using glass microrods. Free cytosolic Ca ²⁺ concentration was monitored using confocal microscopy at resting sarcomere length (≈1.79 μm) and during severe (≈12%) increase in sarcomere length. Results: Diastolic stretch provoked SiS, which was prevented by disrupting microtubules with colchicine, but unaffected by inhibition of NADPH oxidase 2 or scavenging of reactive oxygen species. SiS was absent in Na ⁺ ‐ and Ca ²⁺ ‐free external solution, suggesting that it requires transsarcolemmal influx of Na ⁺ or Ca ²⁺ . Activation of Piezo1 increased baseline spark rate, which was further increased by stretch. TRPA1 (transient receptor potential ankyrin 1) activation also increased baseline spark rate, with no further change upon stretch. SiS was not detectable in the presence of streptomycin (a blocker of nonselective mechano‐sensitive ion channels), and HC‐030031 and A‐967079 (selective blockers of TRPA1), even when Piezo1 was activated. SiS was also observed in pig and human atrial cardiomyocytes. Conclusions: In atrial cardiomyocytes, diastolic stretch enhances Ca ²⁺ ‐spark rate through a mechanism that requires microtubular integrity and TRPA1 but that is independent of redox signaling. TRPA1 emerges as a key regulator of stretch‐induced Ca ²⁺ handling in atrial cells, with potential implications for arrhythmogenesis.

The development of new multianalyte biosensors that can detect multiple classes of biomolecules is highly desirable and will greatly improve medical diagnostics. In the field of infectious diseases, for example, it is beneficial to detect pathogens via nucleic acid analysis together with host immune response markers. In this work, we present a multianalyte-compatible lysis using antimicrobial peptides (AMPs). This strategy enables the simultaneous detection of bacterial DNA and inflammatory biomarkers via multianalyte lateral flow immunoassay (LFIA).