VALERIA BARRECA

Dottoressa di ricerca

ciclo: XXXVI


supervisore: Giuseppe Lupo
relatore: Dr. Maria Luisa Fiani

Titolo della tesi: Innovative approaches to study exosome biogenesis and uptake: Insights into Mannose Receptor-mediated uptake and immunomodulatory effects on Dendritic Cells

Exosomes are gaining recognition as important mediators of intercellular communication, and researcher are focused on their potential clinical applications. However, challenges in accurately isolating exosomes from other types of Extracellular Vesicles (EVs) have hindered both their functional studies and clinical utility. Moreover, many aspects related to exosome biogenesis, interaction with recipient cells, and selective uptake mechanisms remain poorly understood. The aim of this study was to investigate the mechanisms of exosomes internalization and their and immunomodulatory effects on immune cells. To distinguish exosomes from the other EVs, we used the Bodipy FL C16, a fluorescent palmitic acid analogue, that enabled us to identify a discrete subpopulation of small exosomes.The Bodipy C16 is incorporated in the fluorescent phospholipids into specific intracellular organelles, culminating in their integration into the exosomal membrane. The characterization of Bodipy exosomes sheds light on their enrichment in tetraspanin markers, notably CD63 and CD81, along with a minor proportion of CD9. The authentication of the exosomal nature of Bodipy vesicles is achieved through nanoFACS sorting and electron microscopy. As awareness of the pivotal role of exosomes, particularly in immune modulation, continues to grow, the question of their selective or non-selective uptake by recipient cells becomes a central focus. Recent studies have demonstrated that exosomes are particularly enriched in high mannose glycans. Therefore, we investigated exosome internalization by antigen-presenting cells, specifically immature dendritic cells (iDCs) characterized by their expression of the mannose receptor (MR). Hypoxic conditions, which are prevalent in the tumor microenvironment, can induce changes in glycosylation patterns. Thus, we aimed to evaluate the specific uptake mediated by the MR of exosomes secreted under normoxic or hypoxic conditions. This study not only explores the uptake of Bodipy exosomes by iDCs but also elucidates their influence on these cells through fluorescence quantification. The results reveal that exosomes are selectively internalized via the MR by iDCs, prompting significant phenotypic transformations within the DCs, thereby shedding light on the profound immunomodulatory capabilities of exosomes within the innate immune system. This findings shed light on the immunomodulatory properties of exosomes in the innate immune system. However, further research is required to fully understand the underlying mechanisms and utilize the therapeutic potential of these results.

Produzione scientifica

11573/1695419 - 2023 - Metabolic labelling of a subpopulation of small extracellular vesicles using a fluorescent palmitic acid analogue
Barreca, Valeria; Boussadia, Zaira; Polignano, Deborah; Galli, Lorenzo; Tirelli, Valentina; Sanchez, Massimo; Falchi, Mario; Bertuccini, Lucia; Iosi, Francesca; Tatti, Massimo; Sargiacomo, Massimo; Fiani, Maria Luisa - 01a Articolo in rivista
rivista: JOURNAL OF EXTRACELLULAR VESICLES (Järfälla : Co-Action Publishing, 2012-) pp. - - issn: 2001-3078 - wos: (0) - scopus: (0)

11573/1630485 - 2022 - Generation, Characterization, and Count of Fluorescent Extracellular Vesicles
Ferrantelli, Flavia; Tirelli, Valentina; Barreca, Valeria; Manfredi, Francesco - 02a Capitolo o Articolo
libro: Extracellular Vesicles in Diagnosis and Therapy - (978-1-0716-2340-4; 978-1-0716-2341-1)

11573/1635027 - 2022 - Metabolically labeled exosomes for biogenesis and functional studies
Fiani, Maria L.; Barreca, Valeria; Polignano, Deborah; Galli, Lorenzo; Tirelli, Valentina; Sanchez, Massimo; Falchi, Mario; Bertuccini, Lucia; Tatti, Massimo; Sargiacomo, Massimo - 04d Abstract in atti di convegno
rivista: JOURNAL OF EXTRACELLULAR VESICLES (Järfälla : Co-Action Publishing, 2012-) pp. 57-58 - issn: 2001-3078 - wos: (0) - scopus: 2-s2.0-85130138744 (0)
congresso: ISEV 2022 Annual meeting (Lyon; Paris)
libro: ISEV2022 Abstract book - ()

11573/1655006 - 2022 - Engineered Extracellular Vesicles for biogenesis and immunomodulation studies
Galli, Lorenzo; Barreca, Valeria; Polignano, Deborah; Manfredi, Francesco; Bona, Roberta; Sanchez, Massimo; Tirelli, Valentina; Sargiacomo, Massimo; Luisa Fiani, Maria - 04f Poster
congresso: Nanoinnovation 2022 (Faculty of Civil and Industrial Engineering, Sapienza University of Rome, via Eudossiana 18)
libro: Nanoinnovation 2022 Book - ()

11573/1550753 - 2021 - Metabolically labeled exosomes for biogenesis and functional studies
Barreca, V.; Polignano, D.; Galli, L.; Tirelli, V.; Sanchez, M.; Falchi, M.; Bertuccini, L.; Iosi, F.; Sargiacomo, M.; Fiani, M. L. - 04d Abstract in atti di convegno
congresso: 3rd International AICC exosome meeting (Online meeting)
libro: 3rd International AICC exosome meeting - ()

11573/1551081 - 2021 - Genetic and metabolic labelling of Extracellular Vescicles: a new tool for biogenesis studies
Galli, Lorenzo; Manfredi, Francesco; Barreca, Valeria; Sanchez, Massimo; Tirelli, Valentina; Falchi, Mario; Federico, Maurizio; Sargiacomo, Massimo; Luisa Fiani, Maria - 04f Poster
congresso: 3rd International AICC exosome meeting (Online meeting)
libro: 3rd International AICC exosome meeting - ()

11573/1486548 - 2020 - Exploiting Manipulated Small Extracellular Vesicles to Subvert Immunosuppression at the Tumor Microenvironment through Mannose Receptor/CD206 Targeting
Luisa Fiani, Maria; Barreca, Valeria; Sargiacomo, Massimo; Ferrantelli, Flavia; Manfredi, Francesco; Federico, Maurizio - 01g Articolo di rassegna (Review)
rivista: INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES (Basel: MDPI Center) pp. - - issn: 1422-0067 - wos: WOS:000569615200001 (12) - scopus: 2-s2.0-85090236868 (13)

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