Assessing the toxicity of one-step-synthesized PEG-coated gold nanoparticles: in vitro and in vivo studies.

OBJECTIVE: To evaluate the in vitro and in vivo toxicities of polyethylene glycol-coated gold nanoparticles synthesized using a one-step process. METHODS: Gold nanoparticles were prepared via a co-precipitation method using polyethylene glycol, and the synthesis product was characterized. For the in vitro evaluation, a flow cytometry analysis with Annexin V and iodide propidium staining was used to assess cytotoxicity in MG-63 cells labeled with 10, 50, and 100µg/mL of nanoparticle concentration. For the in vivo evaluation, nanoparticles were administered intraperitoneally at a dose of 10mg/kg dose in 10-week-old mice. Toxicity was assessed 24 hours and 7 days after administration via histopathological analysis of various tissues, as well as through renal, hepatic, and hematopoietic evaluations. RESULTS: Synthesized nanoparticles exhibited different hydrodynamic sizes depending on the medium: 51.27±1.62nm in water and 268.12±28.45nm (0 hour) in culture medium. They demonstrated a maximum absorbance at 520nm and a zeta potential of -8.419mV. Cellular viability exceeded 90%, with less than 3% early apoptosis, 6% late apoptosis, and 1% necrosis across all labeling conditions, indicating minimal cytotoxicity differences. Histopathological analysis highlighted the accumulation of nanoparticles in the mesentery; however, no lesions or visible agglomeration was observed in the remaining tissues. Renal, hepatic, and hematopoietic analyses showed no significant differences at any time point. CONCLUSION: Polyethylene glycol-coated gold nanoparticles exhibit extremely low toxicity and high biocompatibility, showing promise for future studies.

Breast Cancer Treatment Using the Magneto-Hyperthermia Technique Associated with Omega-3 Polyunsaturated Fatty Acids' Supplementation and Physical Training.

Breast cancer (BC) presents a growing global concern, mainly for the female population of working age. Their pathophysiology shows challenges when attempting to ensure conventional treatment efficacy without adverse effects. This study aimed to evaluate the efficacy of magneto-hyperthermia (MHT) therapy associated with supplementation with omega-3 polyunsaturated fatty acid (w-3 PUFA) and engagement in physical training (PT) for the triple-negative BC (TNBC) model. First, we assessed the physicochemical properties of iron oxide nanoparticles (ION) in biological conditions, as well as their heating potential for MHT therapy. Then, a bioluminescence (BLI) evaluation of the best tumor growth conditions in the TNBC model (the quantity of implanted cells and time), as well as the efficacy of MHT therapy (5 consecutive days) associated with the previous administration of 8 weeks of w-3 PUFA and PT, was carried out. The results showed the good stability and potential of ION for MHT using 300 Gauss and 420 kHz. In the TNBC model, adequate tumor growth was observed after 14 days of 2 × 106 cells implantation by BLI. There was a delay in tumor growth in animals that received w-3 and PT and a significant decrease associated with MHT. This pioneering combination therapy approach (MHT, omega-3, and exercise) showed a positive effect on TNBC tumor reduction and demonstrated promise for pre-clinical and clinical studies in the future.

Assessing the toxicity of one-step-synthesized PEG-coated gold nanoparticles: in vitro and in vivo studies

ABSTRACT Objective To evaluate the in vitro and in vivo toxicities of polyethylene glycol-coated gold nanoparticles synthesized using a one-step process. Methods Gold nanoparticles were prepared via a co-precipitation method using polyethylene glycol, and the synthesis product was characterized. For the in vitro evaluation, a flow cytometry analysis with Annexin V and iodide propidium staining was used to assess cytotoxicity in MG-63 cells labeled with 10, 50, and 100µg/mL of nanoparticle concentration. For the in vivo evaluation, nanoparticles were administered intraperitoneally at a dose of 10mg/kg dose in 10-week-old mice. Toxicity was assessed 24 hours and 7 days after administration via histopathological analysis of various tissues, as well as through renal, hepatic, and hematopoietic evaluations. Results Synthesized nanoparticles exhibited different hydrodynamic sizes depending on the medium: 51.27±1.62nm in water and 268.12±28.45nm (0 hour) in culture medium. They demonstrated a maximum absorbance at 520nm and a zeta potential of -8.419mV. Cellular viability exceeded 90%, with less than 3% early apoptosis, 6% late apoptosis, and 1% necrosis across all labeling conditions, indicating minimal cytotoxicity differences. Histopathological analysis highlighted the accumulation of nanoparticles in the mesentery; however, no lesions or visible agglomeration was observed in the remaining tissues. Renal, hepatic, and hematopoietic analyses showed no significant differences at any time point. Conclusion Polyethylene glycol-coated gold nanoparticles exhibit extremely low toxicity and high biocompatibility, showing promise for future studies.

Current overview of induced pluripotent stem cell-based blood-brain barrier-on-a-chip.

BACKGROUND: Induced pluripotent stem cells (iPSCs) show great ability to differentiate into any tissue, making them attractive candidates for pathophysiological investigations. The rise of organ-on-a-chip technology in the past century has introduced a novel way to make in vitro cell cultures that more closely resemble their in vivo environments, both structural and functionally. The literature still lacks consensus on the best conditions to mimic the blood-brain barrier (BBB) for drug screening and other personalized therapies. The development of models based on BBB-on-a-chip using iPSCs is promising and is a potential alternative to the use of animals in research. AIM: To analyze the literature for BBB models on-a-chip involving iPSCs, describe the microdevices, the BBB in vitro construction, and applications. METHODS: We searched for original articles indexed in PubMed and Scopus that used iPSCs to mimic the BBB and its microenvironment in microfluidic devices. Thirty articles were identified, wherein only 14 articles were finally selected according to the inclusion and exclusion criteria. Data compiled from the selected articles were organized into four topics: (1) Microfluidic devices design and fabrication; (2) characteristics of the iPSCs used in the BBB model and their differentiation conditions; (3) BBB-on-a-chip reconstruction process; and (4) applications of BBB microfluidic three-dimensional models using iPSCs. RESULTS: This study showed that BBB models with iPSCs in microdevices are quite novel in scientific research. Important technological advances in this area regarding the use of commercial BBB-on-a-chip were identified in the most recent articles by different research groups. Conventional polydimethylsiloxane was the most used material to fabricate in-house chips (57%), whereas few studies (14.3%) adopted polymethylmethacrylate. Half the models were constructed using a porous membrane made of diverse materials to separate the channels. iPSC sources were divergent among the studies, but the main line used was IMR90-C4 from human fetal lung fibroblast (41.2%). The cells were differentiated through diverse and complex processes either to endothelial or neural cells, wherein only one study promoted differentiation inside the chip. The construction process of the BBB-on-a-chip involved previous coating mostly with fibronectin/collagen IV (39.3%), followed by cell seeding in single cultures (36%) or co-cultures (64%) under controlled conditions, aimed at developing an in vitro BBB that mimics the human BBB for future applications. CONCLUSION: This review evidenced technological advances in the construction of BBB models using iPSCs. Nonetheless, a definitive BBB-on-a-chip has not yet been achieved, hindering the applicability of the models.

How mesenchymal stem cell cotransplantation with hematopoietic stem cells can improve engraftment in animal models.

BACKGROUND: Bone marrow transplantation (BMT) can be applied to both hematopoietic and nonhematopoietic diseases; nonetheless, it still comes with a number of challenges and limitations that contribute to treatment failure. Bearing this in mind, a possible way to increase the success rate of BMT would be cotransplantation of mesenchymal stem cells (MSCs) and hematopoietic stem cells (HSCs) to improve the bone marrow niche and secrete molecules that enhance the hematopoietic engraftment. AIM: To analyze HSC and MSC characteristics and their interactions through cotransplantation in murine models. METHODS: We searched for original articles indexed in PubMed and Scopus during the last decade that used HSC and MSC cotransplantation and in vivo BMT in animal models while evaluating cell engraftment. We excluded in vitro studies or studies that involved graft versus host disease or other hematological diseases and publications in languages other than English. In PubMed, we initially identified 555 articles and after selection, only 12 were chosen. In Scopus, 2010 were identified, and six were left after the screening and eligibility process. RESULTS: Of the 2565 articles found in the databases, only 18 original studies met the eligibility criteria. HSC distribution by source showed similar ratios, with human umbilical cord blood or animal bone marrow being administered mainly with a dose of 1 × 107 cells by intravenous or intrabone routes. However, MSCs had a high prevalence of human donors with a variety of sources (umbilical cord blood, bone marrow, tonsil, adipose tissue or fetal lung), using a lower dose, mainly 106 cells and ranging 104 to 1.5 × 107 cells, utilizing the same routes. MSCs were characterized prior to administration in almost every experiment. The recipient used was mostly immunodeficient mice submitted to low-dose irradiation or chemotherapy. The main technique of engraftment for HSC and MSC cotransplantation evaluation was chimerism, followed by hematopoietic reconstitution and survival analysis. Besides the engraftment, homing and cellularity were also evaluated in some studies. CONCLUSION: The preclinical findings validate the potential of MSCs to enable HSC engraftment in vivo in both xenogeneic and allogeneic hematopoietic cell transplantation animal models, in the absence of toxicity.

Convalescent plasma therapy in COVID-19 critically ill patients during advanced phases of clinical trials and their preliminary results.

The objective of this study was to highlight the global scientific effort to fight the SARS-CoV-2, addressing the preliminary results of passive immunization through convalescent plasma. We performed a search at the major databases of interventional clinical trial protocols about the transfusion of convalescent plasma in patients with COVID-19, as well as, published articles (n≥25), using the following search strategy: [(COVID-19 OR SARS-CoV-2 OR nCoV-2019) AND (Convalescent plasma OR Plasma exchange) AND (Treatment OR Therapy)]. A total of 24 interventional clinical trial protocols (advanced in phases II-III, III, and IV) were included in this review, as well as three studies that had enough outcomes to evaluate the efficacy of convalescent plasma therapy for patients with COVID-19. All interventional clinical trial protocols applied approximately 500mL of convalescent plasma (from single or more donations) in hospitalized patients, mainly in patients with severe disease associated with standard therapy for COVID-19, and compared to placebo or standard therapy plus specific drugs. Most of interventional clinical trial protocols are multicenter, and the phase IV studies are recruiting at intercontinental centers of North America, Oceania, Europe, but most are recruiting center inside their own county. The three studies published reported similar approach of convalescent plasma intervention with decrease in length of stay, mortality, with less than 4% of adverse events, mainly for treating critical cases with life-threatening disease. All advanced clinical trials focused on convalescent plasma therapy in patients with COVID-19 hospitalized in severe conditions, and the preliminary results provide strong evidence for therapy for the COVID-19 patients.

Convalescent plasma therapy in COVID-19 critically ill patients during advanced phases of clinical trials and their preliminary results / Terapia com plasma convalescente em pacientes graves com COVID-19 nas fases avançadas dos ensaios clínicos e seus resultados preliminares

ABSTRACT The objective of this study was to highlight the global scientific effort to fight the SARS-CoV-2, addressing the preliminary results of passive immunization through convalescent plasma. We performed a search at the major databases of interventional clinical trial protocols about the transfusion of convalescent plasma in patients with COVID-19, as well as, published articles (n≥25), using the following search strategy: [(COVID-19 OR SARS-CoV-2 OR nCoV-2019) AND (Convalescent plasma OR Plasma exchange) AND (Treatment OR Therapy)]. A total of 24 interventional clinical trial protocols (advanced in phases II-III, III, and IV) were included in this review, as well as three studies that had enough outcomes to evaluate the efficacy of convalescent plasma therapy for patients with COVID-19. All interventional clinical trial protocols applied approximately 500mL of convalescent plasma (from single or more donations) in hospitalized patients, mainly in patients with severe disease associated with standard therapy for COVID-19, and compared to placebo or standard therapy plus specific drugs. Most of interventional clinical trial protocols are multicenter, and the phase IV studies are recruiting at intercontinental centers of North America, Oceania, Europe, but most are recruiting center inside their own county. The three studies published reported similar approach of convalescent plasma intervention with decrease in length of stay, mortality, with less than 4% of adverse events, mainly for treating critical cases with life-threatening disease. All advanced clinical trials focused on convalescent plasma therapy in patients with COVID-19 hospitalized in severe conditions, and the preliminary results provide strong evidence for therapy for the COVID-19 patients.

RESUMO O objetivo deste estudo foi destacar o esforço científico global para combater o SARS-CoV-2 abordando os resultados preliminares da imunização passiva por plasma convalescente. Foi realizada uma busca nas principais bases de dados dos protocolos de ensaios clínicos intervencionistas sobre transfusão de plasma convalescente em pacientes com COVID-19, bem como artigos publicados (n≥25), utilizando a seguinte estratégia de busca: [(COVID-19 OR SARS-CoV-2 OR nCoV-2019) AND (Convalescent plasma OR Plasma exchange) AND (Treatment OR Therapy)]. Um total de 24 protocolos de ensaios clínicos intervencionistas (avançados nas fases II-III, III e IV) foi incluído nesta revisão, assim como três estudos que tiveram resultados suficientes para avaliar a eficácia da terapia com plasma convalescente para pacientes com COVID-19. Todos os protocolos de ensaios clínicos intervencionistas aplicaram cerca de 500mL de plasma convalescente (de uma ou mais doações) em pacientes hospitalizados, principalmente naqueles com grau grave de doença associada à terapia-padrão para COVID-19 em comparação com placebo ou terapia-padrão mais medicamentos específicos. A maioria dos protocolos de ensaios clínicos intervencionistas é multicêntrica, e os estudos de fase IV estão recrutando em centros intercontinentais da América do Norte, Oceania e Europa, mas a maior parte dos centros de recrutamento está dentro de seu próprio país. Os três estudos publicados relataram abordagem semelhante de intervenção para plasma convalescente com redução do tempo de internação, mortalidade e menos de 4% de eventos adversos, principalmente para o tratamento de casos críticos com risco de vida. Todos os ensaios clínicos avançados focaram na terapia com plasma convalescente em pacientes com COVID-19 hospitalizados em condições graves, e os resultados preliminares fornecem fortes evidências para a terapia para esses pacientes com COVID-19.