Banca de QUALIFICAÇÃO: BEATRIZ SANTANA MENDONCA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BEATRIZ SANTANA MENDONCA
DATE: 07/02/2024
TIME: 08:30
LOCAL: icbs
TITLE:

Morphological and molecular characterization of human thymic epithelial cells after stimulation with TGF-β1 in vitro

KEY WORDS:

thymus; thymic epithelial cells; TGF-β1

PAGES: 70
BIG AREA: Ciências Biológicas
AREA: Farmacologia
SUBÁREA: Farmacologia Bioquímica e Molecular
SUMMARY:

The thymus is a lymphoid organ responsible for fundamental events for the development of the organism’s cellular immunity, such as maturation, differentiation and selection of T lymphocytes. In this context, thymic epithelial cells (TECs), which make up the majority of the thymic microenvironment, they actively participate in the differentiation stages of functionally competent T lymphocytes. TGF-β1 is a protein related to the process of rhymus involution and epithelial-mesenchymal transition, and has also been reported as an inducer of oxidative stress. Therefore, the objective of this work was to evaluate the morphological and molecular changes induced by TGF-β1 in thymic epithelial cells in vitro. For this, TECs from the human THPN lineage were used and the parameters of morphology, laminin production and some markers related to TGF-β1 were evaluated, such as p-smad, vimentin, E-cadherin, N-cadherin and LIF, in addition to the antioxidant markers SOD2 and CAT. It was observed that TGF-β1 was able to induce changes in the morphology of TECs, which began to present a larger and more elongated morphology compared to cells without stimulation. Futhermore, an increase in the fluorescence intensity of phosphorylated Smad was seen when cells were stimulated with TGF-β1 and an increase in laminin production. Through qPCR, it was possible to observe that TGF-β1 induced the TEM process, through an increase in the expression of N-cadherin and a decrease in E-cadherin, a decrease in the expression of the LIF receptor (LIFR) was also seen. Finally, to evaluate oxidative stress, there was a decrease in the expression of the antioxidant enzyme CAT when TECs were stimulated with TGF- β1. Thus, with the results obtained, it can be concluded that TECs, when stimulated with TGF- β1, present cellular and molecular modifications similar to those found in TECs during thymic involution, such as an increase in extracellular matrix, modification to a mesenchymal profile and loss of antioxidant homeostasis, making it a possible instrument for studying changes in TECs during aging.

COMMITTEE MEMBERS:
Presidente - 2270384 - MARIA DANIELMA DOS SANTOS REIS
Interno(a) - 1544773 - TIAGO GOMES DE ANDRADE
Externo(a) ao Programa - 1370651 - THAIS FERNANDA DE CAMPOS FRAGA DA SILVA - UFAL