Dados do Resumo

Título

DISCOVERY OF NOVEL ANIMAL-FREE DERIVED-EXTRACELLULAR MATRICES FOR 3D SCAFFOLD DESIGN FOR DEVELOPMENT OF MAMMARY GLAND SPHEROIDS

Introdução

In vitro models mimic natural tissue physiology using 3D structures made from extracellular matrix (ECM) materials, including tumor ECM. Driven by new animal welfare regulations, the market seeks novel biomaterials. Mimicking natural ECM is challenging due to its impact on cell organization and adhesion. Key questions include: How can we stimulate cell organization and facilitate effective signaling between cells and ECM? New materials often lack defined analysis techniques, requiring new methodologies.

Objetivo

Our goal is to explore cost-effective materials for creating a microenvironment that mimics mammary gland tissue.

Métodos

This report is divided into three parts. The first part details the results obtained from printing parameters and different blends of potato starch. Parameters such as viscosity, printing resolution, extrudability, and thickness were crucial in achieving a stable, low-degradability printed shape. In the second part, 17 synthesized linear peptides were derived from laminin γ1, γ2, γ4, β3, α1, α5, collagen VI, and keratan sulfate proteoglycan. An adhesion tests was done with MCF10A and MCF7 cells lines. The third part examined hydrogels, with modification with methacrylamide for UV crosslinking.

Resultados

Starch scaffolds were optimized by determining the ideal chitosan concentration (high and low molecular weights) and testing drying conditions (80°C and freeze-drying). The optimal combination was 1% high molecular weight chitosan and 99% starch, dried at 80°C.

The polysaccharide was modified with methyl methacrylate groups for UV crosslinking, resulting in a hydrogel. FTIR confirmed the modification with a peak at 1724 cm-1. The polysaccharide was mixed with alginate, and a viability test using DAPI and propidium iodide in an IBIDI slide (10 µL per well) over 72 hours showed 72% viability.

Additionally, 17 peptides were synthesized using Fmoc, of which 9 enhanced MDA MB 231 cell adhesion, as measured by a colorimetric assay at 600 nm after 45 minutes.

Conclusões

Starch and chitosan scaffolds showed low degradation in vitro. The next step is to test these materials with cells and use histology techniques. For hydrogel, staining with PI and DAPI has been the most effective for comparing cell viability. The optimal mixture was alginate and polysaccharide, but further optimization is needed by testing three stiffness levels and analyzing their effects on cells. To enhance these biomaterials, peptides will be incorporated.

Financiador do resumo

INCT, Cnpq

Palavras Chave

scaffolds; polysaccharides