Evaluating the Acceptability, Swallowability, and Palatability of Film-Coated Mini-Tablet Formulation in Young Children: Results from an Open-Label, Single-Dose, Cross-Over Study.

Mini-tablets are advantageous over liquid formulations in overcoming challenges related to stability, taste, and dosage. This open-label, single-dose, cross-over study investigated the acceptability and safety of drug-free, film-coated mini-tablets in children aged 1 month-6 years (stratified: 4-6 years, 2-<4 years, 1-<2 years, 6-<12 months, and 1-<6 months), and their preference for swallowing either a high quantity of 2.0 mm or a low quantity of 2.5 mm diameter mini-tablets. The primary endpoint was acceptability derived from swallowability. The secondary endpoints were investigator-observed palatability, acceptability as a composite endpoint derived from both swallowability and palatability, and safety. Of 320 children randomized, 319 completed the study. Across all tablet sizes, quantities and age groups, acceptability rates based on swallowability were high (at least 87%). Palatability was rated as "pleasant/neutral" in 96.6% of children. The acceptability rates as per the composite endpoint were at least 77% and 86% for the 2.0 mm and 2.5 mm film-coated mini-tablets, respectively. No adverse events or deaths were reported. Recruitment in the 1-<6-months group was stopped early due to coughing-evaluated as "choked on" in three children. Both 2.0 mm and 2.5 mm film-coated mini-tablets are suitable formulations for young children.

CEACAM1 promotes CD8+ T cell responses and improves control of a chronic viral infection.

Dysfunction of CD8+ T cells can lead to the development of chronic viral infection. Identifying mechanisms responsible for such T cell dysfunction is therefore of great importance to understand how to prevent persistent viral infection. Here we show using lymphocytic choriomeningitis virus (LCMV) infection that carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is fundamental for recruiting lymphocyte-specific protein kinase (Lck) into the T cell receptor complex to form an efficient immunological synapse. CEACAM1 is essential for activation of CD8+ T cells, and the absence of CEACAM1 on virus-specific CD8+ T cells limits the antiviral CD8+ T cell response. Treatment with anti-CEACAM1 antibody stabilizes Lck in the immunological synapse, prevents CD8+ T cell exhaustion, and improves control of virus infection in vivo. Treatment of human virus-specific CD8+ T cells with anti-CEACAM1 antibody similarly enhances their proliferation. We conclude that CEACAM1 is an important regulator of virus-specific CD8+ T cell functions in mice and humans and represents a promising therapeutic target for modulating CD8+ T cells.

Tumor and endothelial cell-derived microvesicles carry distinct CEACAMs and influence T-cell behavior.

Normal and malignant cells release a variety of different vesicles into their extracellular environment. The most prominent vesicles are the microvesicles (MVs, 100-1000 nm in diameter), which are shed of the plasma membrane, and the exosomes (70-120 nm in diameter), derivates of the endosomal system. MVs have been associated with intercellular communication processes and transport numerous proteins, lipids and RNAs. As essential component of immune-escape mechanisms tumor-derived MVs suppress immune responses. Additionally, tumor-derived MVs have been found to promote metastasis, tumor-stroma interactions and angiogenesis. Since members of the carcinoembryonic antigen related cell adhesion molecule (CEACAM)-family have been associated with similar processes, we studied the distribution and function of CEACAMs in MV fractions of different human epithelial tumor cells and of human and murine endothelial cells. Here we demonstrate that in association to their cell surface phenotype, MVs released from different human epithelial tumor cells contain CEACAM1, CEACAM5 and CEACAM6, while human and murine endothelial cells were positive for CEACAM1 only. Furthermore, MVs derived from CEACAM1 transfected CHO cells carried CEACAM1. In terms of their secretion kinetics, we show that MVs are permanently released in low doses, which are extensively increased upon cellular starvation stress. Although CEACAM1 did not transmit signals into MVs it served as ligand for CEACAM expressing cell types. We gained evidence that CEACAM1-positive MVs significantly increase the CD3 and CD3/CD28-induced T-cell proliferation. All together, our data demonstrate that MV-bound forms of CEACAMs play important roles in intercellular communication processes, which can modulate immune response, tumor progression, metastasis and angiogenesis.