10 research outputs found
Colorectal Cancer Triple Co-culture Spheroid Model to Assess the Biocompatibility and Anticancer Properties of Polymeric Nanoparticles
Colorectal cancer (CRC) is the third most common and the second deadliest type of cancer worldwide, urging the development of more comprehensive models and of more efficient treatments. Although the combination of nanotechnology with chemo- and immuno-therapy has represented a promising treatment approach, its translation to the clinic has been hampered by the absence of cellular models that can provide reliable and predictive knowledge about the in vivo efficiency of the formulation. Herein, a 3D model based on CRC multicellular tumor spheroids (MCTS) model was developed by combining epithelial colon cancer cells (HCT116), human intestinal fibroblasts and monocytes. The developed MCTS 3D model mimicked several tumor features with cells undergoing spatial organization and producing extracellular matrix, forming a mass of tissue with a necrotic core. Furthermore, monocytes were differentiated into macrophages with an anti-inflammatory, pro-tumor M2-like phenotype. For a combined chemoimmunotherapy effect, spermine-modified acetalated dextran nanoparticles (NPs) loaded with the chemotherapeutic Nutlin-3a (Nut3a) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were produced and tested in 2D cultures and in the MCTS 3D model. NPs were successfully taken-up by the cells in 2D, but in a significant less extent in the 3D model. However, these NPs were able to induce an anti-proliferative effect both in the 2D and in the 3D models. Moreover, Nut3a was able to partially shift the polarization of the macrophages present in the MCTS 3D model towards an anti-tumor M1-like phenotype. Overall, the developed MCTS 3D model showed to recapitulate key features of tumors, while representing a valuable model to assess the effect of combinatorial nano-therapeutic strategies in CRC. In addition, the developed NPs could represent a promising approach for CRC treatment.Peer reviewe
Targeted Reinforcement of Macrophage Reprogramming Towards M2 Polarization by IL-4 Loaded Hyaluronic Acid Particles
Correction: ACS Omega 2019, 4, 3, 5931-5931 DOI: 10.1021/acsomega.9b00668Peer reviewe
Hybrid red blood cell membrane coated porous silicon nanoparticles functionalized with cancer antigen induce depletion of T cells
Erythrocyte-based drug delivery systems have been investigated for their biocompatibility, long circulation time, and capability to transport cargo all around the body, thus presenting enormous potential in medical applications. In this study, we investigated hybrid nanoparticles consisting of nano-sized autologous or allogeneic red blood cell (RBC) membranes encapsulating porous silicon nanoparticles (PSi NPs). These NPs were functionalized with a model cancer antigen TRP2, which was either expressed on the surface of the RBCs by a cell membrane-mimicking block copolymer polydimethylsiloxane-b-poly-2-methyl-2-oxazoline, or attached on the PSi NPs, thus hidden within the encapsulation. When in the presence of peripheral blood immune cells, these NPs resulted in apoptotic cell death of T cells, where the NPs having TRP2 within the encapsulation led to a stronger T cell deletion. The deletion of the T cells did not change the relative proportion of CD4+ and cytotoxic CD8+ T cells. Overall, this work shows the combination of nano-sized RBCs, PSi, and antigenic peptides may have use in the treatment of autoimmune diseases.Peer reviewe
Scaffold Vaccines for Generating Robust and Tunable Antibody Responses
Traditional bolus vaccines often fail to sustain robust adaptive immune responses, typically requiring multiple booster shots for optimal efficacy. Additionally, these provide few opportunities to control the resulting subclasses of antibodies produced, which can mediate effector functions relevant to distinct disease settings. Here, it is found that three scaffold-based vaccines, fabricated from poly(lactide-co-glycolide) (PLG), mesoporous silica rods, and alginate cryogels, induce robust, long-term antibody responses to a model peptide antigen gonadotropin-releasing hormone with single-shot immunization. Compared to a bolus vaccine, PLG vaccines prolong germinal center formation and T follicular helper cell responses. Altering the presentation and release of the adjuvant (cytosine-guanosine oligodeoxynucleotide, CpG) tunes the resulting IgG subclasses. Further, PLG vaccines elicit strong humoral responses against disease-associated antigens HER2 peptide and pathogenic E. coli, protecting mice against E. coli challenge more effectively than a bolus vaccine. Scaffold-based vaccines may thus enable potent, durable and versatile humoral immune responses against disease
Relatório de estágio em farmácia comunitária
Relatório de estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia da Universidade de Coimbr
EpCAM-Conjugated porous silicon nanoparticles for targeted cancer chemoimmunotherapy
Monografia realizada no âmbito da unidade Estágio Curricular do Mestrado Integrado em Ciências Farmacêuticas, apresentada à Faculdade de Farmácia da Universidade de CoimbraPorous silicon (PSi) nanoparticles (NPs) are known for being high efficient drug
delivery vehicles for poorly water-soluble drugs, e.g. anticancer agents. However, bare NPs
lack efficiency as they do not specifically target cancer cells, thus not avoiding interaction
with healthy cells.
In this work, sorafenib, an anticancer agent, loaded undecylenic acid thermally
hydrocarbonized PSi (UnTHCPSi) NPs were successfully biofunctionalized with anti-EpCAM
antibody (Ab), to target CD326 receptor overexpressing cells in order to enhance
intracellular uptake and avoid interaction with healthy cells. In addition to the improvement
of sorafenib dissolution in plasma by the UnTHCPSi NPs, these NPs have also shown low
cytotoxicity, resulting in enhanced biocompatibility. The biofunctionalization with the
antibody have led to a significant increase in cellular uptake by MCF-7 breast cancer cells
(CD326 overexpressing cells) when compared with the control, MDA-MB-231 breast cancer
cells (do not express CD326). Besides, the enhanced cellular uptake has resulted in a
significant increase in the in vitro antiproliferation effect. The results were confirmed by TEM,
flow cytometry and confocal microscopy.
Our achievements demonstrated the potential of the anti-EpCAM conjugated
UnTHCPSi NPs to enhance anticancer therapy by improving drug release, intracellular
uptake and active targeting.Nanoparticulas (NPs) porosas de silício (PSi) são veículos altamente eficientes para
entrega de fármacos pouco hidrossolúveis, como por exemplo, fármacos anticancerígenos.
Contudo, este tipo de NPs têm falta de eficácia se não sofrerem funcionalização. Isto devese
à sua baixa especificidade para células cancerígenas, o que leva a interacções indesejáveis
com as células saudáveis.
Neste trabalho, o fármaco anticancerígeno sorafenib foi incorporado, com sucesso, em
NPs porosas de silício tratadas com ácido undecilénico (UnTHCPSi) e posteriormente
biofuncionalizadas com o anticorpo anti-EpCAM. Além de promoverem a dissolução do
sorafenib no plasma, estas NPs possuem baixa citotoxicidade, resultando numa maior
biocompatibilidade. A biofuncionalização com o anticorpo levou a um aumento significativo
do uptake pelas células mamárias cancerígenas MCF-7 (sobreexpressam o receptor CD326),b quando comparadas com as MDA-MB-231 (não expressam o receptor e por isso são
consideradas como grupo controlo). Este aumento resultou num maior efeito
antiproliferativo, in vitro.
Os resultados, confirmados por microscopia electrónica de transmissão, citometria de
fluxo e microscopia confocal, demonstraram que as UnTHCPSi NPs conjugadas com o
anticorpo anti-EpCAM, têm capacidade para melhorar a terapia anticancerígena, através de
um aperfeiçoamento da libertação do fármaco, uptake intracelular e targeting
Relatório de estágio em farmácia comunitária
Relatório de estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia da Universidade de Coimbr
Progress in Stimuli-Responsive Biomaterials for Treating Cardiovascular and Cerebrovascular Diseases
Cardiovascular and cerebrovascular diseases (CCVDs) describe abnormal vascular system conditions affecting the brain and heart. Among these, ischemic heart disease and ischemic stroke are the leading causes of death worldwide, resulting in 16% and 11% of deaths globally. Although several therapeutic approaches are presented over the years, the continuously increasing mortality rates suggest the need for more advanced strategies for their treatment. One of these strategies lies in the use of stimuli-responsive biomaterials. These “smart” biomaterials can specifically target the diseased tissue, and after “reading” the altered environmental cues, they can respond by altering their physicochemical properties and/or their morphology. In this review, the progress in the field of stimuli-responsive biomaterials for CCVDs in the last five years, aiming at highlighting their potential as early-stage therapeutics in the preclinical scenery, is described