Impact of social distancing from the COVID-19 pandemic on the immuno-inflammatory response of older adults.

BACKGROUND: Older adults, as the population considered at increased risk for severe COVID-19, were the most impacted by social isolation. Thus, this study aimed to assess the salivary immune/inflammatory response of older adults before and during the COVID-19 pandemic. METHODS: A cohort of 11 older adults (mean age 66.8 ± 6.1) was followed at three different time points: before (S1) and after 6 (S2) and 20 months (S3) of the beginning of the COVID-19 pandemic in Brazil. Unstimulated saliva samples were obtained to assess the levels of antibodies (secretory IgA, IgG and IgM) by ELISA and cytokines (IL-2, IL-5, IL-6, IL-8 and IL-10, TSLP, IFN-γ, TNF-α) by multiplex analysis. Significant differences were evaluated using the Kruskal-Wallis test with Dunn's post-test. RESULTS: None volunteer presented periodontal disease or caries. All volunteers received at least two doses of the COVID-19 vaccines after S2 and before S3. A tendency to increase salivary levels of SIgA and IgM at S2 and of IgG at S3 were observed compared to the values found at S1 and S2. Significantly decreased levels of IL-2 and IL-5 were found at S2 and S3 (p < 0.001) time points. Lower levels of IFN-γ were found at S2 as compared to the values observed at S1 (p < 0.01). A significant decrease in the IFN-γ/IL-10 ratio was found at S2 (p < 0.01). When assessing the Th1/Th2 ratios, a significant decrease was found in the IFN-γ/TSLP ratio at S2 (p < 0.001) and S3 (p < 0.001) when compared to the values at S1. In addition, a significant increase was observed in the TNF-α/IL-5 ratio at S2 (p < 0.001) and S3 (p < 0.001) in comparison to the values at S1. In a similar way, an increase in the TNF-α/IL-6 ratio (Fig. 5E) was observed at S3 (p < 0.001) when compared to the values at S1. CONCLUSIONS: Overall, this study provides valuable insights into the impact of COVID-19-induced social isolation on immune/inflammatory responses in the upper airway mucosa, particularly those present in oral cavity, of older adults. It demonstrates that a controlled shift in Th1 and Th2 immune responses, both during infection and post-vaccination, can create favorable conditions to combat viral infections without exacerbating the immune response or worsening the pathology.

Development of a highly cytotoxic, clinical-grade virus-specific T cell product for adoptive T cell therapy.

At present, recipients of allogeneic hematopoietic stem-cells are still suffering from recurrent infections after transplantation. Infusion of virus-specific T cells (VST) post-transplant reportedly fights several viruses without increasing the risk of de novo graft-versus-host disease. This study targeted cytomegalovirus (CMV) for the development of an innovative approach for generating a very specific VST product following Good Manufacturing Practices (GMP) guidelines. We used a sterile disposable compartment named the Leukoreduction System Chamber (LRS-chamber) from the apheresis platelet donation kit as the starting material, which has demonstrated high levels of T cells. Using a combination of IL-2 and IL-7 we could improve expansion of CMV-specific T cells. Moreover, by developing and establishing a new product protocol, we were able to stimulate VST proliferation and favors T cell effector memory profile. The expanded VST were enriched in a closed automated system, creating a highly pure anti-CMV product, which was pre-clinically tested for specificity in vitro and for persistence, biodistribution, and toxicity in vivo using NOD scid mice. Our results demonstrated very specific VST, able to secrete high amounts of interferon only in the presence of cells infected by the human CMV strain (AD169), and innocuous to cells partially HLA compatible without viral infection.

A Review of Advanced Cutaneous Melanoma Therapies and Their Mechanisms, from Immunotherapies to Lysine Histone Methyl Transferase Inhibitors.

Advanced cutaneous melanoma is considered to be the most aggressive type of skin cancer and has variable rates of treatment response. Currently, there are some classes of immunotherapy and target therapies for its treatment. Immunotherapy can inhibit tumor growth and its recurrence by triggering the host's immune system, whereas targeted therapy inhibits specific molecules or signaling pathways. However, melanoma responses to these treatments are highly heterogeneous, and patients can develop resistance. Epigenomics (DNA/histone modifications) contribute to cancer initiation and progression. Epigenetic alterations are divided into four levels of gene expression regulation: DNA methylation, histone modification, chromatin remodeling, and non-coding RNA regulation. Deregulation of lysine methyltransferase enzymes is associated with tumor initiation, invasion, development of metastases, changes in the immune microenvironment, and drug resistance. The study of lysine histone methyltransferase (KMT) and nicotinamide N-methyltransferase (NNMT) inhibitors is important for understanding cancer epigenetic mechanisms and biological processes. In addition to immunotherapy and target therapy, the research and development of KMT and NNMT inhibitors is ongoing. Many studies are exploring the therapeutic implications and possible side effects of these compounds, in addition to their adjuvant potential to the approved current therapies. Importantly, as with any drug development, safety, efficacy, and specificity are crucial considerations when developing methyltransferase inhibitors for clinical applications. Thus, this review article presents the recently available therapies and those in development for advanced cutaneous melanoma therapy.

Bioluminescence Imaging and ICP-MS Associated with SPION as a Tool for Hematopoietic Stem and Progenitor Cells Homing and Engraftment Evaluation.

Bone marrow transplantation is a treatment for a variety of hematological and non-hematological diseases. For the transplant success, it is mandatory to have a thriving engraftment of transplanted cells, which directly depends on their homing. The present study proposes an alternative method to evaluate the homing and engraftment of hematopoietic stem cells using bioluminescence imaging and inductively coupled plasma mass spectrometry (ICP-MS) associated with superparamagnetic iron oxide nanoparticles. We have identified an enriched population of hematopoietic stem cells in the bone marrow following the administration of Fluorouracil (5-FU). Lately, the cell labeling with nanoparticles displayed the greatest internalization status when treated with 30 µg Fe/mL. The quantification by ICP-MS evaluate the stem cells homing by identifying 3.95 ± 0.37 µg Fe/mL in the control and 6.61 ± 0.84 µg Fe/mL in the bone marrow of transplanted animals. In addition, 2.14 ± 0.66 mg Fe/g in the spleen of the control group and 2.17 ± 0.59 mg Fe/g in the spleen of the experimental group was also measured. Moreover, the bioluminescence imaging provided the follow up on the hematopoietic stem cells behavior by monitoring their distribution by the bioluminescence signal. Lastly, the blood count enabled the monitoring of animal hematopoietic reconstitution and ensured the transplantation effectiveness.

In vitro differentiation of myeloid suppressor cells (MDSC-like) from an immature myelomonocytic precursor THP-1.

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with a potent suppressor profile that regulates immune responses. These cells are one of the main components of the microenvironment of several diseases, including solid and hematologic tumors, autoimmunities, and chronic inflammation. However, their wide use in studies is limited due to they comprehend a rare population, which is difficult to isolate, expand, differentiate, and maintain in culture. Additionally, this population has a complex phenotypic and functional characterization. OBJECTIVE: To develop a protocol for the in vitro production of MDSC-like population from the differentiation of the immature myeloid cell line THP-1. METHODS: We stimulated THP-1 with G-CSF (100 ng/mL) and IL-4 (20 ng/mL) for seven days to differentiate into the MDSC-like profile. At the end of the protocol, we characterized these cells phenotypically and functionally by immunophenotyping, gene expression analysis, cytokine release dosage, lymphocyte proliferation, and NK-mediated killing essays. RESULTS: We differentiate THP-1 cells in an MDSC-like population, named THP1-MDSC-like, which presented immunophenotyping and gene expression profiles compatible with that described in the literature. Furthermore, we verified that this phenotypic and functional differentiation did not deviate to a macrophage profile of M1 or M2. These THP1-MDSC-like cells secreted several immunoregulatory cytokines into the microenvironment, consistent with the suppressor profile related to MDSC. In addition, the supernatant of these cells decreased the proliferation of activated lymphocytes and impaired the apoptosis of leukemic cells induced by NK cells. CONCLUSIONS: We developed an effective protocol for MDSC in vitro production from the differentiation of the immature myeloid cell line THP-1 induced by G-CSF and IL-4. Furthermore, we demonstrated that THP1-MDSC-like suppressor cells contribute to the immune escape of AML cells. Potentially, these THP1-MDSC-like cells can be applied on a large-scale platform, thus being able to impact the course of several studies and models such as cancer, immunodeficiencies, autoimmunity, and chronic inflammation.

Evaluation of Atypical Chemokine Receptor Expression in T Cell Subsets.

Chemokines are molecules that pertain to a family of small cytokines and can generate cell chemotaxis through the interaction with their receptors. Chemokines can trigger signaling via conventional G-protein-coupled receptors or through atypical chemokine receptors. Currently, four atypical chemokine receptors have been are described (ACKR1, ACKR2, ACKR3 and ACKR4). ACKRs are expressed in various cells and tissues, including T lymphocytes. These receptors' main function is related to the internalization and degradation of chemokines, as well as to the inflammation control. However, the expression of these receptors in human T lymphocytes is unclear in the literature. The objective of this study was to evaluate the expression of ACKRs in different subpopulations of T lymphocytes. For this, peripheral blood from healthy donors was used to analyze the expression of ACKR2, ACKR3 and ACKR4 by immunophenotyping CD4, CD8 T lymphocytes and, in their subsets, naive, transition and memory. Results obtained in this study demonstrated that ACKR2, ACKR3 and ACKR4 receptors were expressed by T lymphocytes subsets in different proportions. These receptors are highly expressed in the cytoplasmic milieu of all subsets of T lymphocytes, therefore suggesting that their expression in plasma membrane is regulated after transcription, and it must be dependent on a stimulus, which was not identified in our study. Thus, regarding ACKRs function as scavenger receptors, at least for the ACKR3, this function does not impair the chemotaxis exert for their ligand compared to the typical counterpart receptor.

HLA-DRB1 and cytokine polymorphisms in Brazilian patients with myelodysplastic syndromes and its association with red blood cell alloimmunization.

OBJECTIVE(S): This study aimed investigate association of HLA-DRB1 and cytokine polymorphisms with red blood cell(RBC) alloimmunization in Brazilian Myelodysplastic syndrome(MDS) patients with prior exposure to RBC transfusion. BACKGROUND: MDS patients are at risk RBC alloimmunization due to chronic RBC transfusion. However, differences in immune response of MDS transfused patients are not completely known. METHODS/MATERIALS: A retrospective cohort of 87 polytransfused patients with MDS including 28 alloimmunized (PA) and 59 non-alloimmunized (PNA) was evaluated in three Brazilian reference hospitals. HLA-DRB1genotype was performed by polymerase chain reaction (PCR)-SSOP (Luminex platform) and cytokine polymorphisms analysed by PCR and TaqMan assays. RESULTS: While HLA-DRB1 allele frequencies did not differ between groups, IL17A 197G > A SNP and IL4 polymorphisms showed significant correlation with RBC alloimmunization. IL17A 197A allele A and AA genotype were significantly more frequent in PA than PNA(A, 46.4% versus 27.1%, p = 0.012; OR = 2.3; 95%CI = 1.1-4.9; AA, 25% versus 6.8%, p = 0.041; OR = 6.2; 95%CI 1.3-30.8). Moreover, significant association of alloimmunization to Rh antigens with IL17A 197A allele and AA genotype was also identified in PA group(A, 45% versus 27.1%, p = 0.036; OR = 2.5; 95% CI 1.1-5.7; AA, 30% versus 6.8%, p = 0.042; OR = 7.9; 95%CI 1.5-42.3). Genotype A1A2 of IL4 intron 3 was overrepresented in PA(50% versus 16.9%, p = 0.009; OR = 4.97; 95%CI 1.6-15.5). Similarly, IL4-590 CT genotype was overrepresented in PA(53.6% versus 28.8%, p = 0.049; OR = 3.3; 95%CI 1.2-9.3). CONCLUSIONS: This study showed no association regarding HLA-DRB1 alleles for RBC alloimmunization risk or protection, however the IL17A 197G>A, IL4 intron 3 and IL4 590C>T SNP was significantly associated to RBC alloimmunization risk in this cohort of Brazilian MDS patients.

Optimization of Multimodal Nanoparticles Internalization Process in Mesenchymal Stem Cells for Cell Therapy Studies.

Considering there are several difficulties and limitations in labeling stem cells using multifunctional nanoparticles (MFNP), the purpose of this study was to determine the optimal conditions for labeling human bone marrow mesenchymal stem cells (hBM-MSC), aiming to monitor these cells in vivo. Thus, this study provides information on hBM-MSC direct labeling using multimodal nanoparticles in terms of concentration, magnetic field, and period of incubation while maintaining these cells' viability and the homing ability for in vivo experiments. The cell labeling process was assessed using 10, 30, and 50 µg Fe/mL of MFNP, with periods of incubation ranging from 4 to 24 h, with or without a magnetic field, using optical microscopy, near-infrared fluorescence (NIRF), and inductively coupled plasma mass spectrometry (ICP-MS). After the determination of optimal labeling conditions, these cells were applied in vivo 24 h after stroke induction, intending to evaluate cell homing and improve NIRF signal detection. In the presence of a magnetic field and utilizing the maximal concentration of MFNP during cell labeling, the iron load assessed by NIRF and ICP-MS was four times higher than what was achieved before. In addition, considering cell viability higher than 98%, the recommended incubation time was 9 h, which corresponded to a 25.4 pg Fe/cell iron load (86% of the iron load internalized in 24 h). The optimization of cellular labeling for application in the in vivo study promoted an increase in the NIRF signal by 215% at 1 h and 201% at 7 h due to the use of a magnetized field during the cellular labeling process. In the case of BLI, the signal does not depend on cell labeling showing no significant differences between unlabeled or labeled cells (with or without a magnetic field). Therefore, the in vitro cellular optimized labeling process using magnetic fields resulted in a shorter period of incubation with efficient iron load internalization using higher MFNP concentration (50 µgFe/mL), leading to significant improvement in cell detection by NIRF technique without compromising cellular viability in the stroke model.

Senescence State in Mesenchymal Stem Cells at Low Passages: Implications in Clinical Use.

Mesenchymal stem cells (MSCs) are multipotent cells found in various tissues and are easily cultivated. For use in clinical protocols, MSCs must be expanded to obtain an adequate number of cells, but a senescence state may be instituted after some passages, reducing their replicative potential. In this study, we report a case where MSC derived from an elderly donor acquired a senescence state after three passages. The bone marrow was aspirated from a female patient submitted to a cell therapy for the incontinency urinary protocol; MSCs were cultivated with DMEM low glucose, supplemented with 10% autologous serum (AS) plus 1% L-glutamine and 1% antibiotic/antimycotic. Senescence analysis was performed by ß-galactosidase staining after 24 and 48 h. Controls were established using BM-MSC from healthy donors and used for senescence and gene expression assays. Gene expression was performed using RT-PCR for pluripotency genes, such as SOX2, POU5F1, NANOG, and KLF4. MSC telomere length was measured by the Southern blotting technique, and MSCs were also analyzed for their capacity to differentiate into adipocytes, chondrocytes, and osteocytes. The patient's MSC expansion using AS displayed an early senescence state. In order to understand the role of AS in senescence, MSCs were then submitted to two different culture conditions: 1) with AS or 2) with FBS supplementation. Senescence state was assessed after 24 h, and no statistical differences were observed between the two conditions. However, patients' cells cultured with AS displayed a higher number of senescence cells than FBS medium after 48 h (p = 0.0018). Gene expression was performed in both conditions; increased expression of KLF4 was observed in the patient's cells in comparison to healthy controls (p = 0.0016); reduced gene expression was observed for NANOG (p = 0.0016) and SOX2 (p = 0.0014) genes. Telomere length of the patient's cells was shorter than that of a healthy donor and that of a patient of similar age. Osteocyte differentiation seemed to be more diffuse than that of the healthy donor and that of the patient of similar age. MSCs could enter a senescence state during expansion in early passages and can impact MSC quality for clinical applications, reducing their efficacy when administered.

Extracellular vesicles cargo from head and neck cancer cell lines disrupt dendritic cells function and match plasma microRNAs.

Extracellular vesicles (EVs) are mediators of the immune system response. Encapsulated in EVs, microRNAs can be transferred between cancer and immune cells. To define the potential effects of EVs originated from squamous cell carcinoma cells on immune system response, we performed microRNA profiling of EVs released from two distinct cell lines and treated dendritic cells derived from circulating monocytes (mono-DCs) with these EVs. We confirmed the internalization of EVs by mono-DCs and the down-regulation of microRNA mRNA targets in treated mono-DCs. Differences in surface markers of dendritic cells cultivated in the presence of EVs indicated that their content disrupts the maturation process. Additionally, microRNAs known to interfere with dendritic cell function, and detected in EVs, matched microRNAs from squamous cell carcinoma patients' plasma: miR-17-5p in oropharyngeal squamous cell carcinoma, miR-21 in oral squamous cell carcinoma, miR-16, miR-24, and miR-181a circulating in both oral and oropharyngeal squamous cell carcinoma, and miR-23b, which has not been previously described in plasma of head and neck squamous cell carcinoma, was found in plasma from patients with these cancer subtypes. This study contributes with insights on EVs in signaling between cancer and immune cells in squamous cell carcinoma of the head and neck.

In Vitro Evaluation of Hyperthermia Magnetic Technique Indicating the Best Strategy for Internalization of Magnetic Nanoparticles Applied in Glioblastoma Tumor Cells.

This in vitro study aims to evaluate the magnetic hyperthermia (MHT) technique and the best strategy for internalization of magnetic nanoparticles coated with aminosilane (SPIONAmine) in glioblastoma tumor cells. SPIONAmine of 50 and 100 nm were used for specific absorption rate (SAR) analysis, performing the MHT with intensities of 50, 150, and 300 Gauss and frequencies varying between 305 and 557 kHz. The internalization strategy was performed using 100, 200, and 300 µgFe/mL of SPIONAmine, with or without Poly-L-Lysine (PLL) and filter, and with or without static or dynamic magnet field. The cell viability was evaluated after determination of MHT best condition of SPIONAmine internalization. The maximum SAR values of SPIONAmine (50 nm) and SPIONAmine (100 nm) identified were 184.41 W/g and 337.83 W/g, respectively, using a frequency of 557 kHz and intensity of 300 Gauss (≈23.93 kA/m). The best internalization strategy was 100 µgFe/mL of SPIONAmine (100 nm) using PLL with filter and dynamic magnet field, submitted to MHT for 40 min at 44 °C. This condition displayed 70.0% decreased in cell viability by flow cytometry and 68.1% by BLI. We can conclude that our study is promising as an antitumor treatment, based on intra- and extracellular MHT effects. The optimization of the nanoparticles internalization process associated with their magnetic characteristics potentiates the extracellular acute and late intracellular effect of MHT achieving greater efficiency in the therapeutic process.

LN-Derived Fibroblastic Reticular Cells and Their Impact on T Cell Response-A Systematic Review.

Fibroblastic reticular cells (FRCs), usually found and isolated from the T cell zone of lymph nodes, have recently been described as much more than simple structural cells. Originally, these cells were described to form a conduit system called the "reticular fiber network" and for being responsible for transferring the lymph fluid drained from tissues through afferent lymphatic vessels to the T cell zone. However, nowadays, these cells are described as being capable of secreting several cytokines and chemokines and possessing the ability to interfere with the immune response, improving it, and also controlling lymphocyte proliferation. Here, we performed a systematic review of the several methods employed to investigate the mechanisms used by fibroblastic reticular cells to control the immune response, as well as their ability in determining the fate of T cells. We searched articles indexed and published in the last five years, between 2016 and 2020, in PubMed, Scopus, and Cochrane, following the PRISMA guidelines. We found 175 articles published in the literature using our searching strategies, but only 24 articles fulfilled our inclusion criteria and are discussed here. Other articles important in the built knowledge of FRCs were included in the introduction and discussion. The studies selected for this review used different strategies in order to access the contribution of FRCs to different mechanisms involved in the immune response: 21% evaluated viral infection in this context, 13% used a model of autoimmunity, 8% used a model of GvHD or cancer, 4% used a model of Ischemic-reperfusion injury (IRI). Another four studies just targeted a particular signaling pathway, such as MHC II expression, FRC microvesicles, FRC secretion of IL-15, FRC network, or ablation of the lysophosphatidic acid (LPA)-producing ectoenzyme autotaxin. In conclusion, our review shows the strategies used by several studies to isolate and culture fibroblastic reticular cells, the models chosen by each one, and dissects their main findings and implications in homeostasis and disease.

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.

Current Clinical Trials Protocols and the Global Effort for Immunization against SARS-CoV-2.

Coronavirus disease 2019 (COVID-19) is the biggest health challenge of the 21st century, affecting millions of people globally. The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has ignited an unprecedented effort from the scientific community in the development of new vaccines on different platforms due to the absence of a broad and effective treatment for COVID-19 or prevention strategy for SARS-CoV-2 dissemination. Based on 50 current studies selected from the main clinical trial databases, this systematic review summarizes the global race for vaccine development against COVID-19. For each study, the main intervention characteristics, the design used, and the local or global center partnerships created are highlighted. Most vaccine developments have taken place in Asia, using a viral vector method. Two purified inactivated SARS-CoV-2 vaccine candidates, an mRNA-based vaccine mRNA1273, and the chimpanzee adenoviral vaccine ChAdOx1 are currently in phase III clinical trials in the respective countries Brazil, the United Arab Emirates, the USA, and the United Kingdom. These vaccines are being developed based on a quickly formed network of collaboration.

Bone Marrow Monocytes and Derived Dendritic Cells from Myelodysplastic Patients Have Functional Abnormalities Associated with Defective Response to Bacterial Infection.

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic stem cell diseases characterized by dysplasia of one or more hematologic lineages and a high risk of developing into acute myeloid leukemia. MDS patients have recurrent bacterial infections and abnormal expression of CD56 by monocytes. We investigated MDS patients' bone marrow CD56+/CD56- monocytes and their in vitro-derived dendritic cell populations in comparison with cells obtained from disease-free subjects. We found that monocytes from MDS patients, irrespective of CD56 expression, have reduced phagocytosis activity and low expression of genes involved in triggering immune responses, regulation of immune and inflammatory response signaling pathways, and in the response to LPS. Dendritic cells derived in vitro from MDS monocytes failed to develop dendritic projections and had reduced expression of HLA-DR and CD86, suggesting that Ag processing and T cell activation capabilities are impaired. In conclusion, we identified, in both CD56+ and CD56- monocytes from MDS patients, several abnormalities that may be related to the increased susceptibility to infections observed in these patients.

Therapeutic Efficiency of Multiple Applications of Magnetic Hyperthermia Technique in Glioblastoma Using Aminosilane Coated Iron Oxide Nanoparticles: In Vitro and In Vivo Study.

Magnetic hyperthermia (MHT) has been shown as a promising alternative therapy for glioblastoma (GBM) treatment. This study consists of three parts: The first part evaluates the heating potential of aminosilane-coated superparamagnetic iron oxide nanoparticles (SPIONa). The second and third parts comprise the evaluation of MHT multiple applications in GBM model, either in vitro or in vivo. The obtained heating curves of SPIONa (100 nm, +20 mV) and their specific absorption rates (SAR) stablished the best therapeutic conditions for frequencies (309 kHz and 557 kHz) and magnetic field (300 Gauss), which were stablished based on three in vitro MHT application in C6 GBM cell line. The bioluminescence (BLI) signal decayed in all applications and parameters tested and 309 kHz with 300 Gauss have shown to provide the best therapeutic effect. These parameters were also established for three MHT applications in vivo, in which the decay of BLI signal correlates with reduced tumor and also with decreased tumor glucose uptake assessed by positron emission tomography (PET) images. The behavior assessment showed a slight improvement after each MHT therapy, but after three applications the motor function displayed a relevant and progressive improvement until the latest evaluation. Thus, MHT multiple applications allowed an almost total regression of the GBM tumor in vivo. However, futher evaluations after the therapy acute phase are necessary to follow the evolution or tumor total regression. BLI, positron emission tomography (PET), and spontaneous locomotion evaluation techniques were effective in longitudinally monitoring the therapeutic effects of the MHT technique.

Anticancer Activities of the Quinone-Methide Triterpenes Maytenin and 22-ß-hydroxymaytenin Obtained from Cultivated Maytenus ilicifolia Roots Associated with Down-Regulation of miRNA-27a and miR-20a/miR-17-5p.

Natural triterpenes exhibit a wide range of biological activities. Since this group of secondary metabolites is structurally diverse, effects may vary due to distinct biochemical interactions within biological systems. In this work, we investigated the anticancer-related activities of the quinone-methide triterpene maytenin and its derivative compound 22-ß-hydroxymaytenin, obtained from Maytenus ilicifolia roots cultivated in vitro. Their antiproliferative and pro-apoptotic activities were evaluated in monolayer and three-dimensional cultures of immortalized cell lines. Additionally, we investigated the toxicity of maytenin in SCID mice harboring tumors derived from a squamous cell carcinoma cell line. Both isolated molecules presented pronounced pro-apoptotic activities in four cell lines derived from head and neck squamous cell carcinomas, including a metastasis-derived cell line. The molecules also induced reactive oxygen species (ROS) and down-regulated microRNA-27a and microRNA-20a/miR-17-5p, corroborating with the literature data for triterpenoids. Intraperitoneal administration of maytenin to tumor-bearing mice did not lead to pronounced histopathological changes in kidney tissue, suggesting low nephrotoxicity. The wide-ranging activity of maytenin and 22-ß-hydroxymaytenin in head and neck cancer cells indicates that these molecules should be further explored in plant biochemistry and biotechnology for therapeutic applications.

Cytokines Levels and Salivary Microbiome Play A Potential Role in Oral Lichen Planus Diagnosis.

Oral lichen planus (OLP) is a chronic Th1-mediated inflammatory mucocutaneous disease of the skin and oral mucosa that can have various clinical presentations. Lesions are usually bilateral and often painful. While cutaneous Lichen Planus (LP) lesions are self-limiting, the oral lesions are chronic and rarely remissive. The diagnosis of oral lichen planus (OLP) is often challenging, and confirmation by histopathological criterion is generally advised. The aim of our study was to identify the cytokines present in OLP-suggestive lesions and in non-specific inflammatory lesions (NSIL) used as controls. Moreover, assess cytokines protein levels and oral microbiota composition in whole saliva samples. Histopathological analysis, immunohistochemistry and gene expression were used as techniques to analyze the oral mucosal tissue samples. ELISA was conducted to analyze salivary cytokine levels and 16S rRNA sequencing was used to determine the salivary microbiome. As a result we observed larger number of infiltrated lymphocytes (p = 0.025), as well, more T CD4 lymphocytes in the epithelial tissue (p = 0.006) in OLP samples compared to NSIL. In addition, the OLP samples displayed more apoptotic cells compared to NSIL (p = 0.047). Regarding the cytokine analysis, IFN-γ and IL-33 were more expressed in OLP lesions than in NSIL samples (p < 0.001; p = 0.026). Furthermore, our results demonstrated higher levels of IFN-γ protein expression in the saliva of OLP group compared to controls (p = 0.0156). We also observed noted differences in the oral microbiota composition between OLP and NSIL saliva samples. In conclusion, OLP lesions presented larger numbers of apoptotic and inflammatory cells, higher levels of IFN-γ and IL-33 compared to NSIL, and these lesions also differ regarding oral microbiota composition. These results are consistent with the Th-1-mediated chronic inflammation nature of oral lichen planus investigated lesions and displayed unique features that could be used as a diagnostic tool.

Intravenous Grafts of Human Amniotic Fluid-Derived Stem Cells Reduce Behavioral Deficits in Experimental Ischemic Stroke.

Amniotic fluid has been investigated as new cell source for stem cells in the development of future cell-based transplantation. This study reports isolation of viable human amniotic fluid-derived stem cells, labeled with multimodal iron oxide nanoparticles, and its effect on focal cerebral ischemia-reperfusion injury in Wistar rats. Middle cerebral artery occlusion of 60 min followed by reperfusion for 1 h, 6 h, and 24 h was employed in the present study to produce ischemia and reperfusion-induced cerebral injury in rats. Tests were employed to assess the functional outcome of the sensorimotor center activity in the brain, through a set of modified neurological severity scores used to assess motor and exploratory capacity 24 h, 14, and 28 days after receiving cellular therapy via tail vein. In our animal model of stroke, transplanted cells migrated to the ischemic focus, infarct volume decreased, and motor deficits improved. Therefore, we concluded that these cells appear to have beneficial effects on the ischemic brain, possibly based on their ability to enhance endogenous repair mechanisms.