Banca de DEFESA: SUZANNE NERY SERRATH

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : SUZANNE NERY SERRATH
DATE: 24/04/2024
TIME: 08:30
LOCAL: Sala Virtual Remota - https://bit.ly/DefMSc_SuzanneSerrath_PGBIOEXP
TITLE:

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KEY WORDS:

Cr-LAAO, extracellular vesicle, snakebite, inflammation

PAGES: 84
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

Animal venoms are an important source of proteins with high adaptability to the environment. Among these proteins is L-amino acid oxidase (LAAO), which has been studied due to its involvement in various physiopathological effects such as hemolysis, edema, hemorrhage, apoptosis induction, cytotoxicity, microbicidal activities, effects on platelets, and activation of human neutrophils. Exosomes, cellular nanovesicles, play vital roles in intercellular communication, including immune responses, and participate in some inflammatory physiopathological effects such as oxidative stress, which is the main response to neutrophil activation. Thus, this study investigates the impact of LAAO isolated from the venom of the snake Calloselasma rhodostoma (Cr-LAAO) on the release of exosomes from human neutrophils, including activation patterns, proteins identified in the vesicles, and their signaling pathways. Isolated human neutrophils were incubated with RPMI (negative control), PMA (500 ng/mL positive control), and Cr-LAAO (100 μg/mL). Size characterization was performed using dynamic light scattering with the Zetasizer Nano ZS system (Malvern® Instrument). The exosomes were analyzed for surface markers using Western Blot, detecting CD63 and CD81, proteins characteristic of these structures. Through proteomics by mass spectrometry, the proteins present in the exosomes were identified. When analyzing the supernatant of neutrophils stimulated by Cr-LAAO, the presence of particles with exosome characteristics was observed, ranging in size from 8 to 70 nm. The expression of CD63 and CD81 markers in exosomes released by neutrophils stimulated by Cr-LAAO was confirmed by Western blot. In the proteomic analysis of exosomes, approximately 722 proteins were identified in all experimental groups, revealing their interactions and involvement in biological processes, molecular functions, and cellular components. These results provide an enhanced understanding of the role of Cr-LAAO in activating human neutrophils, resulting in the release of exosomes and facilitating intercellular communication. Additionally, they provide crucial information for potential therapeutic approaches in inflammatory and immunological disorders.

COMMITTEE MEMBERS:
Externa à Instituição - BRUNA CAVECCI-MENDONÇA
Presidente - 1726461 - JULIANA PAVAN ZULIANI TRENCH DE SOUZA
Externa à Instituição - LUCIANA LYRA CASAIS E SILVA - UFBA