Biohybrid Hydrogels for Tumoroid Culture.

Tumoroids are 3D in vitro models that recapitulate key features of in vivo tumors, such as their architecture - hypoxic center and oxygenated outer layer - in contrast with traditional 2D cell cultures. Moreover, they may be able to preserve the patient-specific signature in terms of cell heterogeneity and mutations. Tumoroids are, therefore, interesting tools for improving the understanding of cancer biology, developing new drugs, and potentially designing personalized therapeutic plans. Currently, tumoroids are most often established using basement membrane extracts (BME), which provide a multitude of biological cues. However, BME are characterized by a lack of well-defined composition, limited reproducibility, and potential immunogenicity as a consequence of their natural origin. Synthetic polymers can overcome these problems but lack structural and biochemical complexity, which can limit the functional capabilities of organoids. Biohybrid hydrogels consisting of both natural and synthetic components can combine their advantages and offer superior 3D culture systems. In this review, it is summarized efforts devoted to producing tumoroids using different types of biohybrid hydrogels, which are classified according to their crosslinking mechanism.

Immunophenotyping and Cell Sorting of Human MKs from Human Primary Sources or Differentiated In Vitro from Hematopoietic Progenitors.

Megakaryocyte (MK) differentiation encompasses a number of endomitotic cycles that result in a highly polyploid (reaching even >64N) and extremely large cell (40-60 µm). As opposed to the fast-increasing knowledge in megakaryopoiesis at the cell biology and molecular level, the characterization of megakaryopoiesis by flow cytometry is limited to the identification of mature MKs using lineage-specific surface markers, while earlier MK differentiation stages remain unexplored. Here, we present an immunophenotyping strategy that allows the identification of successive MK differentiation stages, with increasing ploidy status, in human primary sources or in vitro cultures with a panel integrating MK specific and non-specific surface markers. Despite its size and fragility, MKs can be immunophenotyped using the above-mentioned panel and enriched by fluorescence-activated cell sorting under specific conditions of pressure and nozzle diameter. This approach facilitates multi-Omics studies, with the aim to better understand the complexity of megakaryopoiesis and platelet production in humans. A better characterization of megakaryopoiesis may pose fundamental in the diagnosis or prognosis of lineage-related pathologies and malignancy.

In Vivo Characterization of a Wireless Telemetry Module for a Capsule Endoscopy System Utilizing a Conformal Antenna.

This paper describes the design, fabrication, packaging, and performance characterization of a conformal helix antenna created on the outside of a capsule endoscope designed to operate at a carrier frequency of 433 MHz within human tissue. Wireless data transfer was established between the integrated capsule system and an external receiver. The telemetry system was tested within a tissue phantom and in vivo porcine models. Two different types of transmission modes were tested. The first mode, replicating normal operating conditions, used data packets at a steady power level of 0 dBm, while the capsule was being withdrawn at a steady rate from the small intestine. The second mode, replicating the worst-case clinical scenario of capsule retention within the small bowel, sent data with stepwise increasing power levels of -10, 0, 6, and 10 dBm, with the capsule fixed in position. The temperature of the tissue surrounding the external antenna was monitored at all times using thermistors embedded within the capsule shell to observe potential safety issues. The recorded data showed, for both modes of operation, a low error transmission of 10-3 packet error rate and 10-5 bit error rate and no temperature increase of the tissue according to IEEE standards.