Extracellular vesicles as human therapeutics: A scoping review of the literature

Extracellular vesicles (EVs) are released by all cells and contribute to cell-to-cell communication. The capacity of EVs to target specific cells and to efficiently deliver a composite profile of functional molecules have led researchers around the world to hypothesize their potential as therapeutics. While studies of EV treatment in animal models are numerous, their actual clinical benefit in humans has more slowly started to be tested. In this scoping review, we searched PubMed and other databases up to 31 December 2023 and, starting from 13,567 records, we selected 40 pertinent published studies testing EVs as therapeutics in humans. The analysis of those 40 studies shows that they are all small pilot trials with a large heterogeneity in terms of administration route and target disease. Moreover, the absence of a placebo control in most of the studies, the predominant local application of EV formulations and the inconsistent administration dose metric still impede comparison across studies and firm conclusions about EV safety and efficacy. On the other hand, the recording of some promising outcomes strongly calls out for well-designed larger studies to test EVs as an alternative approach to treat human diseases with no or few therapeutic options.

Caloric restriction for the immunometabolic control of human health

Nutrition affects all physiological processes occurring in our body, including those related to the function of the immune system; indeed, metabolism has been closely associated with the differentiation and activity of both innate and adaptive immune cells. While excessive energy intake and adiposity have been demonstrated to cause systemic inflammation, several clinical and experimental evidence show that calorie restriction (CR), not leading to malnutrition, is able to delay aging and exert potent anti-inflammatory effects in different pathological conditions. This review provides an overview of the ability of different CR-related nutritional strategies to control autoimmune, cardiovascular, and infectious diseases, as tested by preclinical studies and human clinical trials, with a specific focus on the immunological aspects of these interventions. In particular, we recapitulate the state of the art on the cellular and molecular mechanisms pertaining to immune cell metabolic rewiring, regulatory T cell expansion, and gut microbiota composition, which possibly underline the beneficial effects of CR. Although studies are still needed to fully evaluate the feasibility and efficacy of the nutritional intervention in clinical practice, the experimental observations discussed here suggest a relevant role of CR in lowering the inflammatory state in a plethora of different pathologies, thus representing a promising therapeutic strategy for the control of human health.

[Laws regulating transplantation should express the contemporaneity. Questions to the constitutionalist Francesco Paolo Casavola and to the philosophers Remo Bodei and Aldo Masullo about the possibility deciding the destiny of one's own organs at the time one decides on how to die and on contacts between donor families and recipients.]

Transplantation represents modernity thus the laws regulating the procedure should be continuously renovated and remodeled in order to take full advantage of progress. The debate is about Law no. 219, December 22, 2017 and on Law no. 222, April 1, 1999. The quests are a) about the possibility to modify the first so that people deciding on how they want to die, may also decide about their willingness to allow the removal of their organs for transplantation and b) the possibility for donor families and recipients to have contacts after transplantation in the case both sides agree. Questions were emailed to the constitutionalist Francesco Paolo Casavola, immediate Past President of the National Committee for Bioethics, and to the philosophers Remo Bodei and Aldo Masullo. Their answers received by September 16, support the idea a) to include in the Law no. 219, 2017 the possibility to decide not only on the modality one wants to die but also on the possibility to allow his own organs to be removed for transplantation and b) to liberalize contacts between donor families and recipients when both side agree. For both changes there is enough evidence of their feasibility-necessity. The answers related to contacts between donor families and recipients support the decision of the National Committee for Bioethics on September 27, 2018. Professor Casavola also suggests that contacts should organized and supervised by the ethical committees of the hospitals where the transplantation procedure is accomplished.

[The Italian Places of Nicholas Green 20 years after his assassination]

Twenty years ago, Nicholas Green, a 7- year-old American boy was shot, while on vacation, on the Autostrada (motorway) Salerno to Reggio Calabria in Italy. His organs, with the consent of his parents, Reg and Maggie, were removed and 7 persons had their lives changed. In Italy in these last 20 years, organ donation has increased powerfully from 6.2 to 18.2 per million population with a peak at 20 in 2006. Reg and Maggie Green, after Nicholas death, started campaigning for organ donation by making full use of the media. Italian justice was efficient and the criminals were imprisoned quickly. With popular enthusiasm, a total of 103 places were dedicated to Nicholas (schools, halls, squares, streets, parks, gardens, private collections), a proof of great appreciation. Teaching organ donation to children, nurses and medical students is a powerful tool to convey the message of organ donation. To prevent opposition to organ removal when brain death occurs as Professor Francesco Casavola says signing for organ donation should be a family decision and laws for organ donation should be updated frequently in order to meet the progress of modernity.

Influence of the co-encapsulation of different non-ionic surfactants on the properties of PLGA insulin-loaded microspheres

The aim of this work was to produce insulin-loaded microspheres allowing the preservation of peptide stability during both particle processing and insulin release. Our strategy was to combine the concepts of using surfactants to improve insulin stability while optimising overall microsphere characteristics such as size, morphology, peptide loading and release. Bovine insulin was encapsulated within poly(lactide-co-glycolide) (PLGA 50:50, Resomer RG504H) microspheres by the multiple emulsion-solvent evaporation technique. Microspheres were prepared by adding to the primary emulsion three non-ionic surfactants, poloxamer 188, polysorbate 20 and sorbitan monooleate 80, at different concentrations (1.5 and 3. 0% w/v). The presence of surfactants was found to decrease the mean diameter and to affect the morphology of the microspheres. Insulin encapsulation efficiency was reduced in the presence of surfactants and especially for sorbitan monooleate 80, in a concentration-dependent mode. The influence of the surfactants on the interactions between insulin and PLGA together with the primary emulsion stability were found to be the major determinants of insulin encapsulation. The release of insulin from microspheres was biphasic, showing an initial burst effect followed by a near zero-order release for all the batches prepared. The initial burst was related to the presence of insulin molecules located onto or near to the microsphere surface. In the presence of surfactants, a faster insulin release with respect to microspheres encapsulating insulin alone was observed. Insulin stability within microspheres after processing, storage and release was evaluated by reversed phase- and size-exclusion-HPLC. The analysis of microsphere content after processing and 6 months of storage showed that insulin did not undergo any chemical modification within microspheres. On the contrary, during the period of sustained release insulin was transformed in a high-molecular weight product, the amount of which was related to the surfactant used. In conclusion, polysorbate 20 at 3% w/v concentration was the most effective in giving regular shaped particles with both good insulin loading and slow release, and limiting insulin modification within microspheres.