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Thymoquinone is the most biologically active constituent of Nigella sativa (black seed). A monoterpene compound chemically known as 2-methyl-5-isopropyl-1, 4-quinone. In this study, the gender-dependent pharmacokinetic behavior of thymoquinone in rats was investigated. Thymoquinone was administered orally (20â¯mg/kg) and intravenously (5â¯mg/kg) to male and female rats and blood samples were collected at specific time points. Plasma concentration-time curves were plotted and pharmacokinetic parameters were determined using the non-compartmental analysis. In addition, simulations of steady state concentrations of thymoquinone in male and female rats were performed using GastroPlus PK software. After oral administration, the maximum plasma concentration (Cmax) of thymoquinone was 4.52⯱â¯0.092⯵g/ml in male rats and 5.22⯱â¯0.154⯵g/ml in female rats (pâ¯=â¯0.002). Similarly, after intravenous administration, the Cmax was 8.36⯱â¯0.132⯵g/ml in males and 9.51⯱â¯0.158⯵g/ml in females (pâ¯=â¯0.550). The area under the plasma concentration-time curve (AUC)0-∞ following oral dosing was 47.38⯱â¯0.821⯵g/ml·h in females and 43.63⯱â¯0.953⯵g/ml·h in males (pâ¯=â¯0.014). Pharmacokinetics and plasma concentration vs. time profiles for multiple oral doses of thymoquinone in rats were predicted using a simulation model to compare the simulation results with the experimental plasma pharmacokinetic data. The differences observed in thymoquinone pharmacokinetics between male and female rats after a single dose were not evident for the simulated steady-state parameters. The findings suggest that the gender difference does not seem to play a significant role in thymoquinone disposition at steady state.
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Considerable debate exists regarding the potential antineoplastic effect of dietary long-chain n-3 PUFA contained in fatty fishes. Since the majority of published data has proven that their intake does not induce toxic or carcinogenic effects in humans, their possible preventive use against cancer has been suggested. On the other hand, it is unlikely that they could be effective in cancer patients as a single therapy. Nevertheless, a considerable effort has been put forth in recent years to evaluate the hypothesis that n-3 PUFA might improve the antineoplastic efficiency of currently used anticancer agents. The rationale for this therapeutic combinatory strategy is trying to increase cancer sensitivity to conventional therapies. This could allow the use of lower drug/radiation doses and, thereby, a reduction in the detrimental health effects associated with these treatments. We will here critically examine the studies that have investigated this possibility, by focusing particularly on the biological and molecular mechanisms underlying the antineoplastic effect of these combined treatments. A possible use of n-3 PUFA in combination with the innovative single-targeted anti-cancer therapies, that often are not completely devoid of dangerous side-effects, is also suggested.
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Ácidos Graxos Ômega-3 , Neoplasias/dietoterapia , Antineoplásicos , Quimiorradioterapia Adjuvante , Terapia Combinada , Dieta , Gorduras na Dieta , Humanos , Alimentos MarinhosRESUMO
Background: During percutaneous transluminal coronary angioplasty (PTCA), activated clotting time (ACT) measurements are recommended to attest a correct anticoagulation level and, if needed, to administer further unfractionated heparin (UFH) to obtain a therapeutic ACT value. Our clinical routine led us to observe that smokers had lower ACT values after standardized UFH administration during PTCA. Procoagulant status in smokers is well documented. Objectives: To determine whether tobacco negatively affects UFH anticoagulation during PTCA when evaluated by ACT. Methods: The ACT-TOBACCO trial is a single-center, noninterventional, prospective study. The primary end point is the comparison of ACT values after standardized UFH administration between active smokers and nonsmokers (active smoker group vs nonsmoker group) requiring coronary angiography followed by PTCA. The main secondary end points include ACT comparison after the first and second standardized UFH administration according to the patient's smoking status (active, ex-, or nonsmoker) and the clinical presentation of ischemic cardiomyopathy: stable (silent ischemia or stable angina) or unstable (unstable angina or acute coronary syndrome without or with ST-segment elevation). Conclusions: To the best of our knowledge, ACT values during PTCA between smokers and nonsmokers have not previously been compared. As current PTCA procedures increase in complexity and duration, the understanding of procoagulant risk factors such as smoking and the need for reliable anticoagulation monitoring becomes essential to balance hemorrhagic risk against thrombotic risk.
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Chronic spinal adhesive arachnoiditis (CSAA) is a rare condition with limited therapeutic options. Surgical treatment proves effective in approximately 60% of cases. Conservative treatment options have not been extensively investigated. Here, we report the course of the disease, analyze the effect of immune treatments in patients with CSAA who were treated in the University Hospital Essen between 2015 and 2020, and conduct a literature review. Three out of four patients showed no improvement after treatment with corticosteroids, methotrexate, or plasmapheresis. All non-responders suffered from CSAA for several years, while one patient who had a disease duration of less than one month fully recovered. It is necessary to verify whether treatment at an early stage of the disease is better than treatment after chronic adhesion manifestation, as it interrupts the development of adhesions and all subsequent complications.
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OBJECTIVE: The venom neutralization potential of silver nanoparticle(AgNP-AS) mediated bark extract of Alstonia scholaris Linn R.Br was investigated in the study. METHODS & MATERIALS: AgNP-AS was synthesized with respect to optimal temperature, pH of extract. UV-vis, FT-IR, XRD, TEM, SEM studies were used to characterize silver nanoparticles of Alstonia scholaris Linn(AgNP-AS). The potential of AgNP-AS in neutralization of venom lethality, rise in myotoxicity markers(LDH) and proinflammatory cytokines(IL6, TNFα) were evaluated in animal models. RESULTS: AgNP-AS was synthesized optimally with AgNO3 (2 mM); extract concentration, 0.2 gm/l (1% w/v); extract (pH 9) and optimal temperature (40 °C). The colour change and synthesis of AgNP-AS was validated by UV-vis analysis at 432 nm. Transmission electron microscopy of AgNP-AS showed that the particle size for AgNP-AS was 14 nm-20 nm. FT-IR revealed peaks at 3445 cm-1, 1646 cm-1, 1346 cm-1 and 1108 cm-1. From the dynamic light scattering studies the hydrodynamic diameter (115.87 nm) and zeta potential(-29.8 mV) were estimated. The EDAX exhibited a peak for silver validating that the synthesized silver was pure. The biosynthesized (AgNP-AS) could significantly neutralize Viper russelli venom(VRV) induced rise in serum lactate dehydrogenase(LDH) and proinflammatory cytokines(IL6, TNFα) in animal models. CONCLUSION: The culmination of nanotechnology with herbal medicine might endow with a really constructive tool in coming up with future drugs with fewer toxicity.
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Medulloblastoma (MB) is a common yet highly heterogeneous childhood malignant brain tumor, however, clinically effective molecular targeted therapy is lacking. Modulation of hedgehog (HH) signaling by epigenetically targeting the transcriptional factors GLI through bromodomain-containing protein 4 (BRD4) has recently spurred new interest as potential treatment of HH-driven MB. Through screening of current clinical BRD4 inhibitors for their inhibitory potency against glioma-associated oncogene homolog (GLI) protein, the BRD4 inhibitor 2 was selected as the lead for further structural optimization, which led to the identification of compounds 25 and 35 as the high potency HH inhibitors. Mechanism profiling showed that both compounds suppressed HH signaling by interacting with the transcriptional factor GLI, and were equally potent against the clinical resistant mutants and the wild type of smoothened (SMO) receptor with IC50 values around 1 nmol/L. In the resistant MB allograft mice, compound 25 was well tolerated and markedly suppressed tumor growth at both 5 mg/kg (TGI = 83.3%) and 10 mg/kg (TGI = 87.6%) doses. Although further modification is needed to improve the pharmacokinetic (PK) parameters, compound 25 represents an efficacious lead compound of GLI inhibitors, possessing optimal safety and tolerance to fight against HH-driven MB.
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Percutaneous liver biopsy is a relatively safe procedure with low complication rates. Infections following liver biopsy are uncommon and can lead to a poor outcome. There are limited data on liver biopsy-related infections among liver transplant (LT) recipients. Also, there is a paucity of data regarding the use of prophylactic antibiotics in LT patients undergoing percutaneous liver biopsy. We report a case of systemic sepsis following percutaneous liver biopsy in a LT recipient with choledochojejunal anastomosis. This was followed by severe rejection and deterioration of liver function and recurrence of primary sclerosing cholangitis (PSC) to the extent that he has been listed for retransplantation. This case report emphasizes the potential risk of sepsis in LT recipients with bilioenteric anastomosis undergoing percutaneous liver biopsy. This increased risk may warrant periprocedural broad spectrum antibiotic prophylaxis, in this subgroup of patients.
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BACKGROUND: Checkpoint inhibitors show impressive and durable responses in various cancer types and provide new avenues for cancer immunotherapy. However, these drugs have a variety of adverse events. Common autoimmune-related adverse effects include fatigue, hepatitis, skin rash, endocrine deficiencies, and colitis. Neurotoxicity has been reported, but its incidence and course remain unclear. METHODS: To illustrate the broad spectrum of neurotoxicity, we exemplarily report the neurological adverse events of five patients with melanoma and one patient with differentiated thyroid cancer who received checkpoint inhibitors at Essen University Hospital (Essen, Germany). RESULTS: After treatment with ipilimumab, nivolumab or pembrolizumab, neurotoxic effects included hypophysitis-associated neck pain and headache, Guillain-Barré syndrome, transverse myelitis, acute brachial plexus neuritis, and ocular myasthenia gravis. CONCLUSIONS: Checkpoint inhibitor therapy remains a success story; however, neurological immune-related adverse events may cause severe life-threatening conditions. We propose a guide for the early detection of neurological adverse events during routine clinical treatment to prevent more severe courses of checkpoint inhibitor-induced neurotoxicity.
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BACKGROUND & AIMS: Human allogeneic liver-derived progenitor cells (HALPC, HepaStem®; Promethera Biosciences, Mont-Saint-Guibert, Belgium) are an advanced therapy medicinal product that could potentially alleviate systemic inflammation and ameliorate liver function in patients with acute-on-chronic liver failure (ACLF) or acute decompensation of cirrhosis (AD). METHODS: This open-label phase II study was conducted in 9 centres in Belgium, Spain, and Bulgaria between 2016 and 2019. The primary objective was to assess the safety of HALPC therapy up to Day 28 and the secondary objectives were to assess its safety and preliminary efficacy up to Month 3. RESULTS: The 24 treated patients (mean age: 51 years) were mostly male with an alcoholic cirrhosis. On pre-infusion Day 1, 15 patients had ACLF and 9 patients had AD. Two of the 3 initial patients treated with high HALPC doses (â¼5×106 cells/kg body weight [BW]) had severe adverse bleeding events attributed to treatment. In 21 patients subsequently treated with lower HALPC doses (0.6 or 1.2×106 cells/kg BW, 1 or 2 times 7 days apart), no serious adverse events were related to treatment, and the other adverse events were in line with those expected in patients with ACLF and AD. Overall, markers of systemic inflammation and altered liver function decreased gradually for the surviving patients. The Day-28 and Month-3 survival rates were 83% (20/24) and 71% (17/24), and at Month 3, no patient had ACLF. CONCLUSIONS: The treatment of patients with ACLF or AD with up to 2 doses of 1.2×106 HALPC/kg BW appeared safe. The results of this study support the initiation of a proof-of-concept study in a larger cohort of patients with ACLF to further confirm the safety and evaluate the efficacy of HALPC therapy. CLINICAL TRIALS REGISTRATION: EudraCT 2016-001177-32. LAY SUMMARY: Patients with liver cirrhosis may suffer from the rapid onset of organ failure or multiple organ failure associated with a high risk of death in the short term. This clinical study of 24 patients suggests that an advanced therapy based on the intravenous infusion of low doses of human allogeneic liver-derived progenitor cells is safe and supports the next phase of clinical development of this type of therapy.
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This review covers some of the recent progress in the field of peptide antibiotics with a focus on compounds with novel or established mode of action and with demonstrated efficacy in animal infection models. Novel drug discovery approaches, linear and macrocyclic peptide antibiotics, lipopeptides like the polymyxins as well as peptides addressing targets located in the plasma membrane or in the outer membrane of bacterial cells are discussed.
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BACKGROUND: Intranasally administered dendritic cells (DCs) migrate into blood and thymus to induce immune responses. Regulatory dendritic cells (DCs) are also useful agents for allergy control. However, to the best of our knowledge, the effects of intranasal administration of regulatory DCs on allergy have not been reported until now. Therefore, we examined the effects of intranasal route of administration of CD40-silenced DCs on allergic responses and compared these with the effects of other administration routes, based on our previous findings on the inhibitory effects of CD40-silenced DCs on allergic responses. METHODS: Mice with allergic rhinitis were treated intranasally, subcutaneously, intraperitoneally, or intravenously with CD40-silenced ovalbumin (OVA)-pulsed DCs that were transfected with CD40 siRNAs and pulsed with OVA antigen. The effects of these DCs on allergic reactions and symptoms were estimated. RESULTS: Intranasal, subcutaneous, intraperitoneal, or intravenous administration of OVA-pulsed CD40-silenced DCs inhibited allergic responses and symptoms in mice. Furthermore, intranasal administration of OVA-pulsed CD40-silenced DCs significantly reduced allergic symptoms and the number of eosinophils in the nasal mucosa compared with subcutaneous, intraperitoneal, or intravenous administration of these DCs. Intranasal administration of OVA-pulsed CD40-silenced DCs resulted in significantly up-regulated IL-10, IL-35, and Foxp3 expression, and enhanced the percentage of CD11c+CD40- and CD4+CD25+ cells within the cervical lymph nodes compared to subcutaneous, intraperitoneal, or intravenous routes of administration. CONCLUSIONS: We believe that this is the first report to demonstrate that regulatory DCs infiltrate into the cervical lymph nodes after intranasal administration of these cells and that intranasal administration of regulatory DCs is more effective for the induction of tolerance in the nasal mucosa than subcutaneous, intraperitoneal, or intravenous administration.
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The rapid progress achieved in the development of many biopharmaceuticals had a tremendous impact on the therapy of many metabolic/genetic disorders. This type of fruitful approach, called protein replacement therapy (PRT), aimed to either replace the deficient or malfunctional protein in human tissues that act either in plasma membrane or via a specific cell surface receptor. However, there are also many metabolic/genetic disorders attributed to either deficient or malfunctional proteins acting intracellularly. The recent developments of Protein Transduction Domain (PTD) technology offer new opportunities by allowing the intracellular delivery of recombinant proteins of a given therapeutic interest into different subcellular sites and organelles, such as mitochondria and other entities. Towards this pathway, we applied successfully PTD Technology as a protein therapeutic approach, in vitro, in SCO2 deficient primary fibroblasts, derived from patient with mutations in human SCO2 gene, responsible for fatal, infantile cardioencephalomyopathy and cytochrome c oxidase deficiency. In this work, we radiolabeled the recombinant TAT-L-Sco2 fusion protein with technetium-99 m to assess its in vivo biodistribution and fate, by increasing the sensitivity of detection of even low levels of the transduced recombinant protein. The biodistribution pattern of [99mTc]Tc-TAT-L-Sco2 in mice demonstrated fast blood clearance, significant hepatobiliary and renal clearance. In addition, western blot analysis detected the recombinant TAT-L-Sco2 protein in the isolated mitochondria of several mouse tissues, including heart, muscle and brain. These results pave the way to further consider this PTD-mediated Protein Therapy Approach as a potentially alternative treatment of genetic/metabolic disorders.
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Mucopolysaccharidosis III A (MPS IIIA) is an autosomal recessive lysosomal storage disorder caused by deficiency of the enzyme sulfamidase. The disorder results in accumulation of heparan sulfate, lysosomal enlargement and cellular and organ dysfunction. Patients exhibit progressive neurodegeneration and behavioral problems and no treatment is currently available. Enzyme replacement therapy is explored as potential treatment strategy for MPS IIIA patients and to modify the disease, sulfamidase must reach the brain. The glycans of recombinant human sulfamidase (rhSulfamidase) can be chemically modified to generate CM-rhSulfamidase. The chemical modification reduced the affinity to the cation-independent mannose-6-phosphate receptor with the aim a prolonged higher concentration in circulation and thus at the blood brain barrier. The pharmacokinetic properties in serum and the distribution to brain and to cerebrospinal fluid (CSF) of chemically modified recombinant human sulfamidase (CM-rhSulfamidase) were studied and compared to those of rhSulfamidase, after a single intravenous (i.v.) 30 mg/kg dose in awake, freely-moving male Sprague Dawley rats. Distribution to brain was studied by microdialysis of the interstitial fluid in prefrontal cortex and by repeated intra-individual CSF sampling from the cisterna magna. Push-pull microdialysis facilitated sampling of brain interstitial fluid to determine large molecule concentrations in awake, freely-moving male Sprague Dawley rats. Together with repeated serum and CSF sampling, push-pull microdialysis facilitated determination of CM-rhSulfamidase and rhSulfamidase kinetics after i.v. administration by non-compartments analysis and by a population modelling approach. Chemical modification increased the area under the concentration versus time in serum, CSF and brain interstitial fluid at least 7-fold. The results and the outcome of a population modelling approach of the concentration versus time data indicated that both compounds pass the BBB with an equilibrium established fairly rapid after administration. We suggest that prolonged high serum concentrations facilitated high brain interstitial fluid concentrations, which could be favorable to reach various target cells in the brain.
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BACKGROUND: Primary Immunodeficiency Disorders (PIDs) are well-known disorders in the West. but the recognition and diagnosis of these disorders is challenging in developing countries. We present the spectrum of PIDs seen at a tertiary care center in Pakistan, identified using clinical case definitions and molecular methods. METHODS: A retrospective chart review of children suspected to have PID was conducted at the Aga Khan University Hospital (AKUH) Karachi, Pakistan from 2010 to 2016. Data on demographics, clinical features, family history of consanguinity, sibling death, details of laboratory workup done for PID and molecular tests targeted panel next generation sequencing (NGS) or whole exome sequencing (WES) performed at the Geha laboratory at Boston Children's Hospital, USA was collected. The study was exempted from the Ethical Review Committee of AKUH. RESULTS: A total of 43 children visited the hospital with suspected PID during the study period. Genetic testing was performed in 31/43 (72.1%) children. A confirmed diagnosis of PID was established in 20/43 (46.5%) children. A pathogenic gene variant was identified in 17(85%) of the 20 confirmed cases (Table 1). Twelve (60%) of the confirmed cases of PID were male. The most common presenting symptom was recurrent diarrhea 11/20 (55%). The mean (±S.D) age of the cases at the time of diagnosis was 4.2 (±4.1) years. Chronic granulomatous disease (CGD) was the most common 6/20 (30%) disorder, followed by severe combined immunodeficiency (SCID) 3/20 (15%), leukocyte adhesion deficiency (LAD) 3/20 (15%), agammaglobulinemia/hypogammaglobulinemia 3/20 (15%), and Hermansky-Pudlak Syndrome (HPS) 2/20 (10%). Wiskott-Aldrich Syndrome, Immunodeficiency Centromeric Instability and Facial Anomalies Syndrome (ICF 2), Trichohepatoenteric syndrome (TRES), and C3 deficiency were each diagnosed once {1/20 (4.3%) each} (Table 1). Of these 20 confirmed cases, almost all 19/20 (95%) had a family history of consanguinity. Sibling death was reported in 5/20 (25%) of these cases. Five out of the 20 (25%) children died over the 7-year period for various reasons. CONCLUSION: PIDs are not uncommon in Pakistan; their diagnosis may be missed or delayed due to the overlapping of clinical features of PID with other diseases and a lack of diagnostic facilities. There is a need to build capacity for early recognition and diagnosis of PIDs to decrease morbidity and mortality.
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Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure-activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRß simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy.
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Pyroptosis is a form of programmed cell death, and recently described as a new molecular mechanism of chemotherapy drugs in the treatment of tumors. Miltirone, a derivative of phenanthrene-quinone isolated from the root of Salvia miltiorrhiza Bunge, has been shown to possess anti-cancer activities. Here, we found that miltirone inhibited the cell viability of either HepG2 or Hepa1-6 cells, and induced the proteolytic cleavage of gasdermin E (GSDME) in each hepatocellular carcinoma (HCC) cell line, with concomitant cleavage of caspase 3. Knocking out GSDME switched miltirone-induced cell death from pyroptosis to apoptosis. Additionally, the induction effects of miltirone on GSDME-dependent pyroptosis were attenuated by siRNA-mediated caspase three silencing and the specific caspase three inhibitor Z-DEVD-FMK, respectively. Miltirone effectively elicited intracellular accumulation of reactive oxygen species (ROS), and suppressed phosphorylation of mitogen-activated and extracellular signal-regulated kinase (MEK) and extracellular regulated protein kinases 1/2 (ERK1/2) for pyroptosis induction. Moreover, miltirone significantly inhibited tumor growth and induced pyroptosis in the Hepa1-6 mouse HCC syngeneic model. These results provide a new insight that miltirone is a potential therapeutic agent for the treatment of HCC via GSDME-dependent pyroptosis.
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EGCG (Epigallocatechin-3-gallate) is the major active principle catechin found in green tea. Skepticism regarding the safety of consuming EGCG is gaining attention, despite the fact that it is widely being touted for its potential health benefits, including anti-cancer properties. The lack of scientific data on safe dose levels of pure EGCG is of concern, while EGCG has been commonly studied as a component of GTE (Green tea extract) and not as a single active constituent. This study has been carried out to estimate the maximum tolerated non-toxic dose of pure EGCG and to identify the treatment related risk factors. In a fourteen day consecutive treatment, two different administration modalities were compared, offering an improved [i.p (intraperitoneal)] and limited [p.o (oral)] bioavailability. A trend of dose and route dependant hepatotoxicity was observed particularly with i.p treatment and EGCG increased serum lipid profile in parallel to hepatotoxicity. Fourteen day tolerable dose of EGCG was established as 21.1 mg/kg for i.p and 67.8 mg/kg for p.o. We also observed that, EGCG induced effects by both treatment routes are reversible, subsequent to an observation period for further fourteen days after cessation of treatment. It was demonstrated that the severity of EGCG induced toxicity appears to be a function of dose, route of administration and period of treatment.
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The physical and chemical integrity of a biopharmaceutical must be maintained not only during long-term storage but also during administration. Specifically for the intravenous (i.v.) delivery of a protein drug, loss of stability can occur when the protein formulation is compounded with i.v. bag diluents, thus modifying the original composition of the drug product. Here we present the challenges associated with the delivery of a low-dose, highly potent monoclonal antibody (mAb) via the i.v. route. Through parallel in-use stability studies and conventional formulation development, a drug product was developed in which adsorptive losses and critical oxidative degradation pathways were effectively controlled. This development approach enabled the i.v. administration of clinical doses in the range of 0.1 to 0.5 mg total protein, while ensuring liquid drug product storage stability under refrigerated conditions.
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Anticorpos Monoclonais Humanizados/química , Imunoglobulina G/química , Administração Intravenosa , Animais , Anticorpos Monoclonais Humanizados/uso terapêutico , Células CHO , Cricetinae , Cricetulus , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Estabilidade ProteicaRESUMO
A novel approach for the treatment of ovarian cancer includes immunotherapy with genetically engineered T cells targeted to ovarian cancer cell antigens. Using retroviral transduction, T cells can be created that express an artificial T cell receptor (TCR) termed a chimeric antigen receptor (CAR). We have generated a CAR, 4H11-28z, specific to MUC-16ecto antigen, which is the over-expressed on a majority of ovarian tumor cells and is the retained portion of MUC-16 after cleavage of CA-125. We previously demonstrated that T cells modified to express the 4H11-28z CAR eradicate orthotopic human ovarian cancer xenografts in SCID-Beige mice. However, despite the ability of CAR T cells to localize to tumors, their activation in the clinical setting can be inhibited by the tumor microenvironment, as is commonly seen for endogenous antitumor immune response. To potentially overcome this limitation, we have recently developed a construct that co-expresses both MUC16ecto CAR and IL-12 (4H11-28z/IL-12). In vitro, 4H11-28z/IL-12 CAR T cells show enhanced proliferation and robust IFNγ secretion compared to 4H11-28z CAR T cells. In SCID-Beige mice with human ovarian cancer xenografts, IL-12 secreting CAR T cells exhibit enhanced antitumor efficacy as determined by increased survival, prolonged persistence of T cells, and higher systemic IFNγ. Furthermore, in anticipation of translating these results into a phase I clinical trial which will be the first to study IL-12 secreting CAR T cells in ovarian cancer, an elimination gene has been included to allow for deletion of CAR T cells in the context of unforeseen or off-tumor on-target toxicity.
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Metastatic lesions are responsible for over 90% of breast cancer associated deaths. Therefore, strategies that target metastasis are of particular interest. This study examined the efficacy of natural killer T (NKT) cell activation as a post-surgical immunotherapy in a mouse model of metastatic breast cancer. Following surgical resection of orthotopic 4T1 mammary carcinoma tumors, BALB/c mice were treated with NKT cell activating glycolipid antigens (α-GalCer, α-C-GalCer or OCH) or α-GalCer-loaded dendritic cells (DCs). Low doses of glycolipids transiently reduced metastasis but did not increase survival. A high dose of α-GalCer enhanced overall survival, but was associated with increased toxicity and mortality at early time points. Treatment with α-GalCer-loaded DCs limited tumor metastasis, prolonged survival, and provided curative outcomes in â¼45% of mice. However, survival was not increased further by additional DC treatments or co-transfer of expanded NKT cells. NKT cell activation via glycolipid-loaded DCs decreased the frequency and immunosuppressive activity of myeloid derived suppressor cells (MDSCs) in tumor-resected mice. In vitro, NKT cells were resistant to the immunosuppressive effects of MDSCs and were able to reverse the inhibitory effects of MDSCs on T cell proliferation. NKT cell activation enhanced antitumor immunity in tumor-resected mice, increasing 4T1-specific cytotoxic responses and IFNγ production from natural killer (NK) cells and CD8+ T cells. Consistent with increased tumor immunity, mice surviving to day 150 were resistant to a second tumor challenge. This work provides a clear rationale for manipulating NKT cells to target metastatic disease.