Thermotropic Behavior and Structural Organization of C24:1 Sulfatide Dispersions and Its Mixtures with Cationic Bilayers

Autor(es)

de Andrade, Lucas ; Duarte, Evandro L. ; Lamy, Teresa ; Rozenfeld, Julio H. K.

• Tipo de documento: Artigo Científico
• Fonte: ACS OMEGA; v. N/A, p. 10-pg., 2023-02-02.

Resumo

C24:1 sulfatide (SF) is an endogenous activator of type II NKT cells. The thermotropic behavior and structure of SF dispersions and its mixtures (4.8-16.6 mol %) with cationic dioctadecyldimethylammonium bromide (DODAB) bilayers were investigated by differential scanning calorimetry and electron paramagnetic resonance spectroscopy. The non-interdigitated lamellar structures formed by pure SF display broad thermal events around 27.5 degrees C when heated and cooled. These events disappear upon mixing with DODAB, showing complete lipid miscibility. SF decreases the DODAB gel-phase packing, with a consequent decrease in phase-transition temperatures and cooperativity upon heating. In contrast, SF increases the rigidity of the DODAB fluid phase, resulting in a smaller decrease in transition temperatures upon cooling. The hysteresis between heating and cooling decreased as the SF molar fraction increased. These effects on DODAB are similar to the ones described for other glycolipids, such as alpha GalCer and beta GlcCer. This might be due to the orientation of the rigid and planar amide bond that connects their sphingoid bases and acyl chains, which result in a V-shaped conformation of the glycolipid molecules. The current results may be important to plan and develop new immunotherapeutic tools based on SF. (AU)

• Processo FAPESP: 16/19077-1 - Desenvolvimento de novos adjuvantes de vacinas capazes de ativar células T CD1d-restritas
• Beneficiário: Julio Henrique Kravcuks Rozenfeld
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/13368-4 - Sistemas nanoestruturados: de modelos biomiméticos de membranas a carreadores de bioativos
• Beneficiário: Karin Do Amaral Riske
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 20/01417-6 - Caracterização estrutural de vesículas de DODAB contendo C24:1 sulfatídeo
• Beneficiário: Lucas de Andrade
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 14/50983-3 - INCT 2014: fluidos complexos
• Beneficiário: Antonio Martins Figueiredo Neto
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 21/01593-1 - Múltiplas técnicas físicas na caracterização estrutural de membranas lipídicas de interesse biológico
• Beneficiário: Maria Teresa Moura Lamy
• Modalidade de apoio: Auxílio à Pesquisa - Regular