iBB

Polyurea oxide (PURO) biodendrimers are a class of dendrimers that can trigger osteogenic differentiation of human mesenchymal stem cells (hMSCs). The effect of PURO biodendrimers in the differentiation of hMSCs was found by the single addition to a standard growth medium for MSCs differentiation (without differentiation inducers, e.g. dexamethasone, ascorbic acid, and β-glycerophosphate). These results, published in ACS Applied Bio Materials by Rita Pires and Vasco Bonifácio from BSIRG-iBB and with colleague João Conde from NOVA Medical School, constitute the first report of in vitro osteodifferentiation fully regulated by synthetic soft polymers. The outstanding role of dendrimers in nanomedicine, under clinic translation, combined with this feature is envisaged to foster PURO dendrimers as an important strategy in cell therapy and regenerative medicine.

There is a wide diversity of non-conventional yeast species, which often present distinctive metabolic properties and can therefore impart different flavours and aromas to beer. Because of this, brewers now regard non-conventional yeast species as a tool to differentiate their beers from other products in the market. In fact, some of these yeasts are already used to produce specific beer styles, such as lambics. A study recently published in Food Microbiology, coordinated by Dr. Margarida Palma and Prof. Isabel Sá-Correia and first authored by the BIOTECnico PhD student Nuno Melo, investigates how two non-conventional yeast species commonly found in wineries, Hanseniaspora guilliermondii and Hanseniaspora opuntiae, influence the volatile composition of beer. These two species, initially selected by a preliminary organoleptic evaluation, were found to modulate the aroma profile of beer, namely by increasing phenylethyl acetate concentration (‘rose’, ‘honey’ aroma). These findings highlight the importance of non-conventional yeasts in shaping the aroma profile of beer and suggest a role for Hanseniaspora spp. in improving it.

Cell-based therapies have been showing unprecedented therapeutic potential, already changing the landscape of medical care. Extracellular vesicles are nanoparticles naturally secreted by cells, which are important mediators of intercellular communication in our organism and are able to mediate therapeutic effects from their cells of origin. These vesicles can also be used as drug delivery vehicles to target multiple diseases. In a paper recently published in Frontiers in Cell and Developmental Biology, iBB researchers in collaboration with iMM Lisboa, CQE-IST and the companies PBS Biotech and AventaCell Biomedical, developed a new strategy for the robust and scalable production of extracellular vesicles from mesenchymal stromal cells, using bioreactors and an animal serum-free cell culture supplement. This strategy, developed within the frame of the PhD Program in Bioengineering of Miguel de Almeida Fuzeta, is a relevant step towards the large scale production of extracellular vesicles form different human tissue sources, which are promising tools for the development of new therapies against a variety of diseases, from cardiovascular diseases to cancer.

While pulmonary delivery is highly attractive due to its non-invasive nature, large surface area, possibility of topical and systemic administration, and rapid absorption circumventing the first-pass effect, the absorption of therapeutic proteins is still ineffective, largely due to the immunological and physicochemical barriers of the lungs. Most studies using spray-drying for the nanoencapsulation of drugs focus on the delivery of conventional drugs, which are less susceptible to bioactivity loss, compared to proteins. In a recent publication in the journal Pharmaceutics, Pedro Fonte from BERG-iBB reviewed the development of polymeric nanoparticles by spray-drying for the delivery of therapeutic proteins with an emphasis on its advantages and challenges, and the techniques to evaluate their in vitro and in vivo performance. The protein stability within the carrier and its features were also addressed.

Understanding the rules that govern complex transcriptional regulation has been attempted for many years. In this study, the full network of transcriptional regulatory associations currently known for Saccharomyces cerevisiae, as gathered in the latest release of the YEASTRACT database, was topologically evaluated. Overall, our analyses challenge previous results, pointing out towards the paucity of experimental evidence to support theories. This study, that stems from a collaboration between researchers from BSRG/iBB (Miguel Cacho Teixeira), INESC-ID (Pedro Monteiro) and IGC (Claudine Chaouiya), was just published in Scientific Reports.

Umbilical cord blood (UCB) is an accepted and appealing alternative source of hematopoietic stem/progenitor cells (HSPC) for hematopoietic cell transplants. However, low UCB volume recovered from births results in an unsatisfactory cell dose for transplants in adults, having initially limited transplants of a single UCB unit to pediatric patients. Ex vivo expansion of HSPC based on the addition of exogenous cytokines.has been pursued to address this problem. Notably, selection of individual cytokines and their concentrations for an expansion cocktail has differed between existing strategies. To improve the effectiveness of these platforms, namely targeting clinical approval, iBB researchers optimized the cytokine cocktails in two clinically relevant expansion platforms for HSPC, a liquid suspension culture system (CS_HSPC) and a co-culture system with bone marrow derived mesenchymal stromal cells (CS_HSPC/MSC).. The tailored and novel optimized cocktails determined made it possible to individually maximize cytokine contribution in both studied platforms, leading to an increase in the expansion platform performance, while allowing a rational side-by-side comparison between them and enhancing our knowledge on the impact of cytokine supplementation on the HSPC expansion process. The results achieved were published in Frontiers in Bioengineering and Biotechnology, Stem Cell Systems Bioengineering section.

New drugs are highly needed to treat human candidiasis. The ability to find interesting new drug targets is now expanded by the construction and validation of a global stoichiometric model describing the whole metabolic network in the human pathogen Candida albicans. This application of Systems Biology to tackle pathogenesis is highly innovative, and stems from a collaboration between researchers from BSRG/iBB (Miguel Cacho Teixeira), ITQB-NOVA (Isabel Rocha) and CEB-UMinho (Óscar Dias). The description of this model and of its potential have just been published in Journal of Fungi.

Several studies have shown that the bacterial protein azurin and its derived peptide p28, can serve as a source for the development of emerging therapeutic drugs to treat cancer as well as against various infectious agents, such as viruses and parasites. Based on that, Arsenio M Fialho started collaboration with two Indian partners aiming to study the feasibility of using azurin and its derived peptide p28 as a protein-peptide-based strategy to inhibit/block SARS-CoV-2 infections. So far, based on a molecular docking and molecular dynamics simulations study, we observed that azurin and particularly the p28 peptide interact with SARS-CoV-2- spike (S) receptor-binding domain and form stable complexes. This work has been published in the Journal of Biomolecular Structure and Dynamics.

Cell-based therapies can enhance the specificity of anti-cancer therapeutic agents. In this context, human mesenchymal stromal cells (MSC) hold a promising future as cell delivery systems for anti-cancer proteins due to their innate tropism for tumors. iBB researchers Marília Silva, Gabriel Monteiro, Arsénio Fialho, Nuno Bernardes and Cláudia Lobato da Silva, engineered human MSC through non-viral methods to secrete a human codon-optimized version of azurin (hazu), a bacterial protein with demonstrated anti-cancer activity towards different cancer models in vitro and in vivo. Upon treatment with conditioned media (CM) from these engineered cells, a decrease in cancer cell proliferation, migration and invasion was seen, and an increase in cell death was observed for breast and lung cancer cell models. The results achieved by SCERG- and BSRG-iBB researchers were published in Frontiers in Cell and Developmental Biology, Stem Cell Research section.

The Burkholderia cepacia complex (Bcc) bacteria are feared contaminants in pharmaceutical industries and cause nosocomial outbreaks, posing health threats to immunocompromised individuals and cystic fibrosis (CF) patients. In this study, the adaptation and survival of B. cepacia and B. contaminans isolates was investigated after long-term incubation in nutrient depleted saline solutions supplemented with increasing concentrations of the biocidal preservative benzalkonium chloride (BZK), recreating the storage conditions of pharmaceutical products. This study just published in the section Biosafety and Biosecurity of Frontiers in Bioengineering and Biotechnology is co-authored by several members of Isabel Sá-Correia team from iBB/BSRG. This study reveals mechanisms underlying the prevalence of Bcc bacteria as contaminants of aqueous pharmaceutical products containing BZK, which often lead to false-negative results during quality control and routine testing.

Engineering brain organoids from human induced pluripotent stem cells (hiPSCs) is a powerful tool for modeling brain development and neurological disorders. Rett syndrome (RTT), a rare neurodevelopmental disorder, can greatly benefit from this technology, since it affects multiple neuronal subtypes in forebrain sub-regions. SCERG-iBB researchers have recently established dorsal and ventral forebrain organoids from control and RTT patient-specific hiPSCs recapitulating the 3D organization and functional network complexity of this brain region. The data obtained revealed a premature development of the deep-cortical layer, associated to the formation of TBR1 and CTIP2 neurons, and a lower expression of neural progenitor/proliferative cells in RTT dorsal organoids. Moreover, calcium imaging and electrophysiology analysis demonstrated functional defects of RTT neurons. Additionally, assembly of RTT dorsal and ventral organoids revealed impairments of interneuron’s migration. Overall, these models provide a better understanding of RTT during early stages of neural development, demonstrating a great potential for personalized diagnosis and drug screening. The paper was published in Frontiers in Cell Development Biology.

Quinic acid (QA) is a cyclic polyol exhibiting anticancer properties on several cancers. However, the potential role of QA derivatives against glioblastoma is not well established. Pedro Fonte from BERG-IBB in a joint collaboration with Tampere University, Lady Doak College, University of Aveiro, Faculty of Pharmacy-University of Lisbon, and the Institute for Systems Biology proposed a new strategy for quinic acid delivery for glioblastoma treatment in a recent publication in Future Medicinal Chemistry. Sixteen novel QA derivatives and QA-16 encapsulated poly (lactic-co-glycolic acid) nanoparticles (QA-16-NPs) were screened for their anti-glioblastoma effect. The presence of a tertiary hydroxy and silylether groups in the lead compound were identified for the antitumor activity. QA-16 displayed 90% inhibition with the IC50 of 10.66 μM and 28.22 μM for LN229 and SNB19, respectively. The induction of apoptosis is faster with the increased fold change of caspase 3/7 and reactive oxygen species. Overall, it was observed the QA-16 and QA-16-NPs shows similar cytotoxicity effect, providing the opportunity to use QA-16 as a potential chemotherapeutic agent.

Candida glabrata’s ability to cause persistent human infections is tightly linked to its impressive ability to overcome host immune system defenses. The molecular basis of virulence in this pathogen are far from being clarified, as it lacks many of the typical pathogenesis features displayed by other Candida species. In this study, the transcription factor Tog1 was found to play a key role in the transcriptome-wide response to oxidative stress, enabling higher proliferation upon phagocytosis and increased virulence. The knowledge gathered through this study, by an international team led by Miguel Cacho Teixeira, BSRG-iBB, and just published in Virulence, is expected to contribute to guide the design of more successful therapeutic approaches.

Poly-ɛ-caprolactone (PCL) is a biodegradable polyester that has FDA and CE approval as a medical device. Despite PCL-based NPs being widely studied in the biomedical field for their advantages as controlled drug delivery systems, little data describe PCL NPs’ toxicity, particularly immunotoxicity. In a recent publication in the journal Chemical Research in Toxicology,  Pedro Fonte from BERG-iBB in collaboration with colleagues from the Center for Neuroscience and Cell Biology, University of Coimbra describe the safe-by-design development of nanoparticles for nanomedicine applications. It was concluded that generalizations among different PCL NP delivery systems must be avoided, and that immunotoxicity assessments should be performed in the early stage of product development to increase the clinical success of the nanomedicine.

During chronic respiratory infections of cystic fibrosis (CF) patients, bacteria adaptively evolve in response to the nutritional and immune environment. A research paper from iBB-BSRG researchers, just published in Frontiers in Microbiology (part of the Research Topic: Evolutionary Mechanisms of Infectious Diseases), contributes to the understanding of shared and species specific evolutionary patterns of B. cenocepacia and B. multivorans evolving in the same CF lung environment. Results support the idea that positive selection might be driven by the action of the host immune system, antibiotic therapy and low oxygen and iron concentrations. This research work, coordinated by Prof. Isabel Sá-Correia, results from the PhD thesis in Biotechnology and Biosciences (BIOTECnico program) of A. Amir Hassan. Dr. AA Hassan is currently working at the Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Belgium.

A new paper by researchers from iBB-BSRG describes, for the first time, the involvement of a plasma membrane multidrug/multixenobiotic resistance (MDR/MXR) ABC transporter in yeast thermotolerance. The expression of the ABC transporter Pdr18, required for pleotropic drug resistance and involved in ergosterol transport at the plasma membrane level, is related with decreased plasma membrane permeabilization induced by a supraoptimal growth temperature. Ergosterol biosynthesis and plasma membrane ergosterol content were implicated in yeast response and capacity to overcome stress induced by supraoptimal growth temperatures. These results support the notion that MDR/MXR transporters perform biological activities other than their accepted role as drug/xenobiotic exporters. Cláudia Godinho is the first author of this research work, coordinated by Isabel Sá-Correia and published in the journal Environmental Microbiology.

The effectiveness of antiplasmodial drugs against the blood stage of infection is increasingly threatened by the emergence and spread of drug-resistant parasites. Here a small library of “half-sandwich” cyclopentadienylruthenium(II) compounds of the general formula [(η5-C5R5)Ru(PPh3)(N-N)][PF6] was screened for activity against the blood stage of CQ-sensitive 3D7-GFP, CQ-resistant Dd2, and artemisinin-resistant IPC5202 Plasmodium falciparum strains and the liver stage of Plasmodium berghei. We showed that some of the compounds are potent dual-stage antiplasmodials, displaying Plasmodium falciparum-selective accumulation in infected erythrocytes. The study was coordinated by researchers from Faculdade de Farmácia with collaboration of researchers from IHMT, IMM and iBB-IST (Sandra Pinto). The results were published in Inorg. Chem. 

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) stands out from other plasma membrane lipids as one of the most important regulators of membrane-associated signaling events. PI(4,5)P2 is able to engage in a multitude of simultaneous cellular functions that are temporally and spatially regulated through the presence of localized transient pools of PI(4,5)P2 in the membrane. These pools are crucial for the recruitment, activation, and organization of signaling proteins and consequent regulation of downstream signaling. A review published by the PhD student Luís Borges-Araújo (from the Medical Biochemistry and Biophysics Doctoral Program)  and Fábio Fernandes showcases some of the most important PI(4,5)P2 molecular and biophysical properties, as well as their impact on its membrane dynamics, lateral organization, and interactions with other biochemical partners. The review was published in the Molecules Journal and was selected as the cover of the September issue.

Optimization of biocatalytic processes is crucial to drive down the price of pharmaceutical and other high-value molecules. L-DOPA and dopamine are two molecules with pharmaceutical relevance, often used in the treatment of neurological diseases such as Parkinson’s disease. In a paper published in the Journal of Biotechnology, Biotechnology PhD student Eduardo Brás and supervisors João Pedro Conde (INESC-MN/DBE) and Pedro Fernandes (IBB) used a microfluidic packed-bed reactor to optimize the enzymatic conversion of L-tyrosine to dopamine. The work culminated with the up-scale (780-fold) of the optimal conditions for L-DOPA synthesis, while maintaining the same output as obtained in the miniaturized system. This type of system can be used to expedite process development in the future.

Affinity-triggered hydrogels were created using one of the most selective and high-affinity pairs found in Nature, avidin-biotin. The multimerization of biotin was studied by conjugation into different multi-arm polyethylene glycol molecules. Depending on the multimerization, assemblies with tunable affinity constant were obtained leading to hydrogels with different mechanical properties and controllable erosion time and profiles. The results showed that mimicking natural multivalency gave rise to robust biocompatible hydrogel with applications in tissue engineering and stem cell research. The study results from ongoing collaboration between Cecília Roque (FCT-NOVA) and Tiago Fernandes (DBE-Técnico) and was recently published in the ACS journal Biomacromolecules.

The ability to acquire azole resistance is an emblematic trait of the fungal pathogen Candida glabrata. Understanding the molecular basis of azole resistance in this pathogen is crucial to design more suitable therapeutic strategies. In this study, the transcription factor Rpn4 was found to play a key role in the transcriptome-wide response to fluconazole. Rpn4 is described a new regulator of the ergosterol biosynthesis pathway in C. glabrata, contributing to plasma membrane homeostasis, decreasing azole drug accumulation and, thus, conferring azole resistance. These results  obtained by an international team led by Miguel Cacho Teixeira, BSRG-iBB, just published in Antimicrobial Agents and Chemotherapy, are expected to contribute to maintain the usability of this drug in antifungal therapy.