Μl Medium Research Articles

A Novel Solid Media-Free In-Planta Soybean (Glycine max. (L) Merr.) Transformation Approach.

Soybean's lengthy protocols for transgenic plant production are a bottleneck in the transgenic breeding of this crop. Explants cultured on a medium for an extended duration exhibit unanticipated modifications. Stress-induced somaclonal variations and in vitro contaminations also cause substantial losses of transgenic plants. This effect could potentially be mitigated by direct shoot regeneration without solid media or in-planta transformation. The current study focused primarily on developing a rapid and effective media-free in-planta transformation technique for three soybean genotypes (Wm82) and our newly developed two hybrids, designated as ZX-16 and ZX-3. The whole procedure for a transgenic plant takes the same time as a stable grown seedling. Multiple axillary shoots were regenerated on stable-grown soybean seedlings without the ectopic expression of developmental regulatory genes. An approximate amount of 200 µL medium with a growth regulator was employed for shoot organogenesis and growth. The maximal shoot regeneration percentages in the Wm82 and ZX-3 genotypes were 87.1% and 84.5%, respectively. The stable transformation ranged from 3% to 8.0%, with an average of 5.5%. This approach seems to be the opposite of the hairy root transformation method, which allowed transgenic shoots to be regenerated on normal roots. Further improvement regarding an increase in the transformation efficiency and of this technique for a broad range of soybean genotypes and other dicot species would be extremely beneficial in achieving increased stable transformation.

Quantitatively measuring the cytotoxicity of viscous hydrogels with direct cell sampling in a micro scale format “MicroDrop” and its comparison to CCK8

Tissue engineering holds promise for developing therapeutic applications using viscous materials e.g. hydrogels. However, assessing the cytotoxicity of such materials with conventional assays can be challenging due to non-specific interactions. To address this, we optimized a live/dead staining method for quantitative evaluation and compared it with the conventional CCK8 assay. Our MicroDrop method involved seeding droplets containing 5000 cells in 10 µl medium on 12-well plates. After allowing them to adhere for 4 h, various viscous samples were applied to the cells and measurements were conducted using a fluorescence microscope immediately and at daily intervals up to 72 h. A sodium dodecyl sulfate (SDS) dilution series compared the MicroDrop with the CCK8 assay. The findings revealed a cell-type specific pattern for 10 mg/ml hyaluronic acid (HA), wherein MC3T3-E1 cells maintained 95% viability until 72 h, while L929 cells experienced a gradual decline to 17%. 2 mg/ml HA exhibited consistent viability above 90% across all time points and cell lines. Similarly, fibrin demonstrated 90% viability across dilutions and time points, except for undiluted samples showing a decrease from 85% to 20%. Gelatin-methacrylol sustained viability above 70% across all time points at both 5% and 10% concentrations. The comparison of the SDS dilution series between viability (MicroDrop) and metabolic activity (CCK8) assay showed a correlation coefficient of 0.95. The study validates the feasibility of the established assay, providing researchers with an efficient tool for assessing cytotoxicity in viscous materials. Additionally, it holds the potential to yield more precise data on well-known hydrogels.Graphical

Impact of Mycotoxin Metabolites Deepoxy-Deoxynivalenol and Beta-Zearalenol on Bovine Preimplantation Embryo Development in the Presence of Acetonitrile.

The quality of animal feed is increasingly affected by weather conditions, high humidity, and damage to grains, which have led to various mycotoxin-producing moulds. The aim of this study was to determine the effects of the combination of deepoxy-deoxynivalenol and beta-zearalenol on the development of preimplantation bovine embryos, the extent to which the presence of both mycotoxin metabolites affects the development of in vitro cultured bovine embryos, or whether the effect of both toxins enhances embryotoxicity. Ovaries were transported from the abattoir to the laboratory and, after maturation and fertilisation, zygotes were placed in an embryo culture medium (IVC) with different mycotoxin metabolite concentrations diluted in acetonitrile. It was found that the blastocyst rate of cleaved embryos was affected by 1 μL acetonitrile in 400 μL medium (0.25%) compared to the group without acetonitrile. For this reason, it was decided to use acetonitrile as a control group, and the desired mycotoxin metabolite concentrations were diluted in the lowest possible amount of acetonitrile (0.5 μL) that could be accurately added to the study groups. There was no statistical difference when the higher mycotoxin metabolite concentrations were added.

Comparison of Antioxidant and Antiproliferative Effects of Various Forms of Garlic and Ramsons.

Garlic is known to be rich in antioxidants, inhibit the proliferation of various cancer cells, and hamper cancer formation and growth, but various forms of garlic can differ greatly in these respects. This study aimed to compare the antioxidant properties of acetone, ethanol, and aqueous extracts of fresh Polish and Spanish garlic, black and granulated garlic, as well as fresh and dried ramsons. Extracts of black and granulated garlic showed the lowest total antioxidant capacity (TAC). The content of phenolic compounds correlated with TAC measured by ABTS• decolorization and FRAP methods, and with the results of FRAP and DPPH• decolorization assays. Garlic extracts inhibited the proliferation of PEO1 and SKOV3 ovarian cancer cells and, usually to a smaller extent, MRC-5 fibroblasts. PBS extracts of fresh Spanish garlic showed the highest potency for inhibition of proliferation of PEO1 cells (IC50 of 0.71 µg extract dry mass/100 µL medium). No significant correlation was found between the potency for inhibition of proliferation and the content of phenolics or flavonoids, confirming that phenolics are the main determinants of TAC but do not contribute significantly to the antiproliferative effects of garlic.

Biomimetic Design and Biocompatibility of Biomimetic Calcium Carbonate Nanocomposites for Skeletal Muscle Injury Repair

As an important part of the human body, skeletal muscle is easily damaged in the process of exercise. The purpose of this study is to investigate the controllable construction and biocompatibility of biomimetic calcium carbonate nanocomposites in exercise skeletal muscle repair. In this study, adult healthy mice were selected as the research objects. First, the mice were anesthetized with 2.5% pentobarbital sodium. Then, the mice were fixed and hit with steel balls on the middle part of the gastrocnemius muscle abdomen to establish a skeletal muscle contusion model. The mice were killed by cervical dislocation under anesthesia. The injured gastrocnemius muscles were quickly removed to prepare the cell suspension. 0.8600 g chitosan was weighed and dissolved in 200 ml deionized water. Then, 0.0660 g of calcium chloride dihydrate was added and stirred to dissolve to prepare chitosan calcium carbonate composite. The calcium carbonate composite material with a length of 8.0 cm is cut into a square sheet of stainless steel. The stainless steel plate was sterilized and then placed in a 12 culture plate to dilute the full cells in the culture bottle. The cells were seeded in 12 well culture plates, and 100 μL cells and 600 μL medium were added to each well. The samples were cultured in the incubator (there were three control holes in each group for SEM test, three control holes for fluorescence measurement, and six control holes for MTT measurement). The plates were taken out and placed in a new 24 plate. 1000 μL medium was added. Then. 100 μL MTT solution was added into each well. The biocompatibility test was conducted for 4 h. The GSH PX level in the chitosan calcium carbonate composite group was lower than that in the natural recovery group (P < 0.01). The results showed that chitosan calcium carbonate composite could promote the growth of skeletal muscle cells.

An Endogenous miRNA-Initiated Hybridization Chain Reaction and Subsequent DNAzyme Activation for Cellular Theranostics

An Endogenous miRNA-Initiated Hybridization Chain Reaction and Subsequent DNAzyme Activation for Cellular Theranostics

Abstract 1391: Self-assembling and disassembling bispecific antibody platform for pretargeted radioimmunotherapy against GPA33 in a xenograft model of colorectal peritoneal carcinomatosis

Abstract Objectives: There is increasing interest in the potential role of radioimmunotherapy in the treatment of peritoneal carcinomatosis (PC), locoregional metastasis throughout the peritoneal cavity. We recently described a SADA platform when applied to GD2-specific PRIT using beta and alpha emitting radioisotopes achieved exceptional therapeutic indices (TI) achieving tumor cures without myelo-, renal-, neuro-, or hepatic toxicities (1). We applied SADA technology to a tumor associated antigen GPA33 expressed by colorectal cancer in a PC model, and compared that to a 3 step PRIT which requires a clearing agent (CA), previously reported to produce durable responses including histologic cures of GPA33-expressing SW1222 subcutaneous (2) and intraperitoneal (ip) colorectal xenograft models (3). Methods: SADA BsAb built from a humanized anti-GPA33 single chain Fv (scFv) and a humanized anti-DOTA scFv were expressed using the Expi293 Expression System and purified by affinity chromatography (1). Biochemical purity of >90% was confirmed via size exclusion HPLC and antigen binding confirmed by surface plasmon resonance and by flow cytometry on GPA33(+) cell lines. 8 wk old female athymic nude mice were inoculated ip with 5E6 cells of stably luciferase/GFP-transfected SW1222 in 200 µL media. PC tumor progression was monitored by in vivo BLI. GPA33-SADA and control GD2-SADA were injected intravenously (iv) on day 26, followed 48 hr later with 1 mCi (37 MBq,200 pmol) [177Lu]Lu-DOTA-Bn ip. In the 3 step PRIT group, mice were treated with 250µg (1.19nmol) GPA33-BsAb (n=4) followed 24 hr later by 20 µg (2.21 nmol) of CA iv, before the injection of 1 mCi (37 MBq,200 pmol) [177Lu]Lu-DOTA-Bn ip 4 hr later. In an additional control group, no SADA was given before 1 mCi (37 MBq,200 pmol) [177Lu]Lu-DOTA-Bn ip. Biodistribution was performed 24 hr after injection of ip 177Lu radiohapten. Results: Radioactivity absorbed in harvested ip SW1222 xenograft tumors treated with SADA-GPA33 (4.92 + 1.59 [mean + SD] percentage injected dose per gram [%ID/g]) was greater than that of harvested tumors treated with the traditional 3 step PRIT to GPA33 (2.68 + 0.179 %ID/g, p=0.043) or with negative control SADA-GD2 (0.513 + 0.293 %ID/g, p<0.001). In mice treated with SADA-GPA33, the ratio of tumor-to-organ radioactivity uptake was 19.6 + 5.08 for all organs, 4.12 + 0.734 for kidneys, 30.5 + 6.14 for liver, and 122.8 + 22.6 for blood. Conclusions: SADA-PRIT targeting GPA33 has favorable TI for colorectal PC. When compared to 3 step PRIT, SADA showed more selectivity and TI. {{References}}: 1. Santich BH, Cheal SM, Ahmed M, et al. Clin Cancer Res. 2020; 2. Cheal SM, Xu H, Guo HF, et al. Eur J Nucl Med Mol Imaging. 2016;43(5):925-937.3. Chandler C, Cheal SM, Nash G, et al. Journal of Nuclear Medicine. 2020;61. Citation Format: Sebastian Chung, Mao Wang, Darren Veach, Sarah Cheal, Daniela Burnes Vargas, Shin Hyuk Seo, Blesida Punzalan, Brian Santich, Hong-fen Guo, Hong Xu, Garrett Nash, Andrea Cercek, Christopher Chandler, Steven Larson, Nai-Kong Cheung. Self-assembling and disassembling bispecific antibody platform for pretargeted radioimmunotherapy against GPA33 in a xenograft model of colorectal peritoneal carcinomatosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1391.

Green biosynthesis of silver nanoparticle using Commiphora myrrh extract and evaluation of their antimicrobial activity and colon cancer cells viability

There is increasing attention directed to mineral nanoparticle for intensive applications in various fields of science, such as medicine, chemistry, agriculture, and biotechnology. There is also a growing attentiveness to the use of eco-friendly methods to synthesize nanoparticle without making or using environmentally dangerous substances to human health. This article describes the biological methods for green synthesis using Commiphora myrrha silver nanoparticle (AgNP) extract. C. myrrha-synthesized AgNPs, which were completed by exposing myrrh aqueous extract to silver nitrate, were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, Zetasizer, and ultraviolet–visible spectral analyses. AgNPs were characterized by varying the color of the solution from light yellow to brown and then depicting the surface plasmon-resonance peaks at 445 nm. This study has promising results in the treatment of colon cancer, as it has impressive outcomes using different concentrations of AgNPs in 100 μl medium (30%) compared to control (100%). The results also showed increasing inhibition zones of antibacterial activity with AgNPs in Enterococcus faecalis (59 mm) and Bacillus cereus (51 mm) compared to myrrh aqueous extract. Fungi that were screened for growth inhibition zones were Fusarium oxysporum (20 mm), Alternaria alternata (14 mm), and Trichoderma (10 mm).

Neurokinin-1 Receptor Antagonism Ameliorates Dry Eye Disease by Inhibiting Antigen-Presenting Cell Maturation and T Helper 17 Cell Activation

Neuroinflammation plays an important role in the pathogenesis of ocular surface disease, including dry eye disease (DED), but little is known about the contribution of substance P (SP) to DED. In this study, we investigated the expression of SP at the ocular surface and evaluated its effect on maturation of antigen-presenting cells (APCs), the key cell component involved in the induction of type 17 helper T-cell (Th17) response in DED. The effect of topical blockade of SP signaling was further investigated using neurokinin-1 receptor (NK1R) inhibitors on APC maturation, Th17 cell activation, and disease severity in a mouse model of DED. The results demonstrate that SP is constitutively expressed at the ocular surface, and trigeminal ganglion neurons are the major source of SP in DED. SP derived from trigeminal ganglion enhanced the expression of major histocompatibility complex class II maturation marker by bone marrow-derived dendritic cells, an effect that is abrogated by blockade of SP signaling using NK1R antagonist spantide. Finally, using a well-established murine model of DED, topical treatment of DED mice with NK1R antagonists CP-99,994 and L-733,060 suppressed APC acquisition of major histocompatibility complex class II, reduced Th17 cell activity, and ameliorated DED severity. These findings are of translational value, as they suggest that antagonizing NK1R-mediated SP signaling may be an effective strategy in suppressing Th17-mediated ocular surface disease.

Production of piglets from in vitro-produced blastocysts by ultrasound-guided ovum pick-up from live donors

The objective of this research was to develop a system for piglet production by transvaginal ultrasound-guided ovum pick-up (OPU), in vitro production (IVP) of embryos and embryo transfer. First, to establish a culture system for a small number of oocytes or embryos, we evaluated the effect of different incubation volumes and culture densities on fertilizing ability and developmental competence in vitro. Porcine oocytes derived from slaughterhouse ovaries were matured, fertilized and then cultured in vitro in groups as follows: 50 oocytes in 500 μL medium for IVM, 20 oocytes in 100 μL medium for IVF and 20 embryos in 40 μL medium for IVC (Group I); 20 in 100 μL for IVM, 20 in 100 μL for IVF and 20 in 40 μL for IVC (Group II); and 10 in 100 μL for IVM, 10 in 100 μL for IVF and 10 in 40 μL for IVC (Group III). Percentages of sperm penetration, cleavage and blastocyst formation did not differ among the groups. Second, to increase the collection efficiency of porcine oocytes by transvaginal ultrasound-guided OPU, the effects of aspiration pressure on follicular oocyte collection were assessed. Oocytes were aspirated from ovaries of live sows using 80 or 100 mmHg. The recovered oocytes were divided into four categories according to the surrounding cumulus cells and quality of oocytes. The number of oocytes recovered using 100 mmHg pressure was significantly higher than with 80 mmHg pressure. However, there were no significant differences in the population of oocytes grouped by the morphological criteria, number of blastocysts per session and the total cell number in blastocysts between the two vacuum pressures. Finally, 81 oocytes obtained by OPU from five donor sows were subjected to IVP and 47 transferable embryos (9.4 ± 4.0 [mean ± SD] morulae/blastocysts per session) were obtained at 5 days after IVF. When they were transferred into five recipient gilts (5–16 embryos per recipient), three of five recipients became pregnant and farrowed a total of 12 live piglets. The present results demonstrate that porcine blastocysts can be produced by OPU-IVP and develop to full term after embryo transfer.

Synergistic Effect of Cannabidiol with Conventional Chemotherapy Treatment

Diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) represent the most common and most aggressive forms of Non-Hodgkin lymphoma (NHL) respectively. Traditional chemotherapy includes (C)yclophosphamide, (H)ydroxydaunorubicin, (O)ncovin (vincristine) and (P)rednisone or (P)rednisolone (CHOP); or (R)ituximab-CHOP. However, in the past 10 years, other more targeted drugs have been developed for treatment of NHLs that includes Bruton's tyrosine kinase (BTK) inhibitors such as ibrutinib (IBN) and proteasome inhibitors such as carfilzomib (CFZ). Presently, there is a high interest in the endocannabinoid system, with specific interest in CB1 and CB2 ligands as potential therapeutic targets for both DLBCL and MCL. Cannabidiol (CBD) is a natural cannabinoid analog that has mixed affinity across CB1 and CB2 receptors; known in the literature as a CB1 antagonist and a CB2 agonist. Our previous work has demonstrated that CB1 antagonists has activity against DLBCL and MCL cell lines. Our study is aimed at comparing CBD against conventional chemotherapeutics, individually and in combination, in DLBCL and MCL cell lines. Here, we demonstrate that CBD in combination with known chemotherapeutics, ibrutinib (IBN), carfilzomib (CFZ), zanubrutinib (BGB) and tumorex (TMX), has synergistic potential in treating DLBCL and MCL cell lines.To determine the activity of CBD in comparison to IBN, cells from representative DLBCL (RC) and MCL (Mino) cell lines were plated at 5,000 cells per well. The cells were incubated for 72 hours in 20 µL medium with 10% FBS and 25 µM CBD, IBN or a combination of both. Viability assays were conducted using Celltiter-Glo Luminescent Cell Viability Assay. Experiments were performed 2-3 times independently, and each concentration was tested in triplicate. We next recreated the experiment using a different BTK inhibitor, BGB, instead of IBN. Likewise we next compared CBD to a proteasome inhibitor where cells from representative DLBCL (RC) and MCL (Mino) cell lines were plated at 5,000 cells per well. The cells were incubated for 72 hours in 20 µL medium with 10% FBS and 6 µM CBD, 10 nM CFZ, or a combination of both. Viability assays were conducted using Celltiter-Glo Luminescent Cell Viability Assay. Experiments were performed 2-3 times independently, and each concentration was tested in triplicate. We then followed by recreating the experiment using 12.5 µM of CBD, 250 nM TMX or both.Synergistic potential of CBD with conventional treatment IBN was examined at concentrations of 25μM. Data shows a marked reduction in viability when drugs are used in combination as compared to individual drug response. Combining CBD with IBN lowered the viability to under 25% as compared to control whereas, individually the drugs never fall under 75% of control. A similar pattern of synergy was demonstrated amongst CBD with BGB, CFZ and TMX respectively. This synergist effect more than likely is the result of the drugs effecting two or more different biochemical pathways. However, within keeping of our previous studies, it is a further indication of the viability of targeting the cannabinoid pathway for therapeutic intervention of malignant lymphoma cancer. DisclosuresNo relevant conflicts of interest to declare.

Creatine enhances the duration of sperm capacitation: a novel factor for improving in vitro fertilization with small numbers of sperm.

Why are many sperm required for successful fertilization of oocytes in vitro, even though fertilization occurs in vivo when only a few sperm reach the oocyte? Creatine produced in the ovary promotes efficient fertilization in vivo; however, in vitro, creatine is not contained in the in vitro fertilization (IVF) medium. The IVF medium enables capacitation of sperm. However, the IVF medium does not fully mimic the in vivo environment during fertilization. Consequently, fertilization in vitro is more inefficient than in the oviduct. Follicular and oviductal fluids were collected and then analyzed for creatine and glucose levels. To determine the physiological functions of creatine, the creatine antagonist 3-guanidinopropionic acid (GPA) was injected into hormonally primed mice. Using conventional IVF protocols, sperm were pre-incubated in IVF medium with creatine and then co-cultured with 10 ovulated cumulus-oocyte complexes (1-1000 per oocyte) in 50 μl medium droplets. Glucose and creatine levels were measured using commercial enzymatic assay kits. The effect of creatine in vivo was assessed by mating experiments using mice treated with or without GPA just before ovulation. To assess the functions of sperm incubated in IVF medium containing creatine, we analyzed (1) the motility of sperm using computer-assisted sperm assay, (2) the capacitation level of sperm by western blot analyses, and (3) the condition of sperm acrosomes by peanut agglutinin lectin-FITC staining. Oviductal creatine levels were significantly increased following ovulation. Injecting mice with GPA just before ovulation significantly reduced the number of fertilized oocytes. The addition of creatine to IVF medium enhanced sperm capacitation by increasing ATP levels. Successful fertilization was achieved with as few as five sperm/oocyte in the creatine group, and the number of fertilized oocytes was significantly higher than in the control without creatine (P < 0.01). In the present study, a pharmacological approach, creatine antagonist (GPA) treatment, but not a knockout mouse model, was used to understand the role of creatine in vivo. The role of creatine in fertilization processes can only be shown in a mouse model. A modified IVF technique using creatine-containing medium was developed and shown to markedly improve fertilization with small numbers of sperm. This approach has the potential to be highly beneficial for human assisted reproductive technologies, especially for patients with a limited number of good quality sperm. This work was supported in part by JSPS KAKENHI Grant numbers JP24688028, JP16H05017 (to M.S.), and JP15J05331 (to T.U.), the Japan Agency for Medical Research and Development (AMED) (16gk0110015h0001 to M.S.), and National Institutes of Health (NIH-HD-076980 to J.S.R). The authors have nothing to disclose.

Transplantation of Human Neural Progenitor Cells Reveals Structural and Functional Improvements in the Spastic Han-Wistar Rat Model of Ataxia

The use of regenerative medicine to treat nervous system disorders like ataxia has been proposed to either replace or support degenerating neurons. In this study, we assessed the ability of human neural progenitor cells (hNPCs) to repair and restore the function of dying neurons within the spastic Han-Wistar rat (sHW), a model of ataxia. The sHW rat suffers from neurodegeneration of specific neurons, including cerebellar Purkinje cells and hippocampal CA3 pyramidal cells leading to the observed symptoms of forelimb tremor, hind-leg rigidity, gait abnormality, motor incoordination, and a shortened life span. To alleviate the symptoms of neurodegeneration and to replace or augment dying neurons, neuronal human progenitor cells were implanted into the sHW rats. At 30 d of age, male sHW mutant rats underwent subcutaneous implantation of an Alzet osmotic pump that infused cyclosporine (15 mg/kg/d) used to suppress the rat’s immune system. At 40 d, sHW rats received bilateral injections (500,000 cells in 5 µL media) of live hNPCs, dead hNPCs, live human embryonic kidney cells, or growth media either into the cerebellar cortex or into the hippocampus. To monitor results, motor activity scores (open-field testing) and weights of the animals were recorded weekly. The sHW rats that received hNPC transplantation into the cerebellum, at 60 d of age, displayed significantly higher motor activity scores and sustained greater weights and longevities than control-treated sHW rats or any hippocampal treatment group. In addition, cerebellar histology revealed that the transplanted hNPCs displayed signs of migration and signs of neuronal development in the degenerated Purkinje cell layer. This study revealed that implanted human progenitor cells reduced the ataxic symptoms in the sHW rat, identifying a future clinical use of these progenitor cells against ataxia and associated neurodegenerative diseases.

Performance of Biocept's sample collection for tumor cell analysis.

e23036 Background: Liquid biopsy is a minimally invasive and cost effective way to assess cancer biomarkers without the risk of surgical biopsy complications. Circulating tumor cell (CTC) analysis from body fluids can provide critical information towards early detection, prognosis and treatment decisions. Accurate CTC evaluations require optimal cell preservation. Cell lysis, DNA degradation, or membrane alterations compromise CTC analyses and accurate diagnoses. This work compares Biocept’s proprietary CEE-Sure BCT and Saccomanno's Cytology Fixative largely used for sputum collection. Methods: One million BT474 (HER2 amplified) or H3112 (ALK re-arranged) cells were spiked into 500 µl medium; 500 µl of CEE-Sure or Saccomanno fixative was added. Tubes were stored at 4°C for 1 day, 1 week, or 1 month. Cells were centrifuged, resuspended, and counted (Celigo). Around 150 cells in 15 µl of RPMI medium were flowed into Biocept's microfludic system for cell capture; recovery (%) was calculated. Captured cells were subjected to fluorescent in situ hybridization (FISH) analyses for qualitative signal evaluation. Results: As similar results were observed for both cell lines and all time points, combined data will be shown. Median cell recovery after CEE-Sure incubation was 14.1% (range 1.7–44%, n = 12) vs 5.4% (range 0.07–26.9%, n = 12) in Saccomanno's fixative. Median cell capture of ~150 cells fed into Biocept’s microchannel was 96% (range 72-98%) for CEE-Sure vs 82% (range 21-96%) for Saccomanno. Paired t-tests showed significant differences for both recovery and capture. FISH signals from CEE-Sure samples were qualitatively rated Fair to Good, while Saccomanno samples had Poor to Fair, grainy, non-specific signals. Conclusions: This preliminary work shows consistently higher cell recovery, better cell membrane maintenance, and higher quality FISH signals for samples stored in Biocept's CEE-Sure vs Saccomano’s fixative. With liquid biopsy testing gaining rapid traction, maximal cell stability during the transport and storage are crucial. Additional fixative comparison is ongoing in various patient specimen types. These results support expansion of molecular analyses in sputum samples enriched for lung epithelial cells.

Human vascular endothelial cells transport foreign exosomes from cow's milk by endocytosis.

Encapsulation of microRNAs in exosomes confers protection against degradation and a vehicle for shuttling of microRNAs between cells and tissues, and cellular uptake by endocytosis. Exosomes can be found in foods including milk. Humans absorb cow's milk exosomes and deliver the microRNA cargo to peripheral tissues, consistent with gene regulation by dietary nucleic acids across species boundaries. Here, we tested the hypothesis that human vascular endothelial cells transport milk exosomes by endocytosis, constituting a step crucial for the delivery of dietary exosomes and their cargo to peripheral tissues. We tested this hypothesis by using human umbilical vein endothelial cells and fluorophore-labeled exosomes isolated from cow's milk. Exosome uptake followed Michaelis-Menten kinetics (Vmax = 0.057 ± 0.004 ng exosome protein × 40,000 cells/h; Km = 17.97 ± 3.84 μg exosomal protein/200 μl media) and decreased by 80% when the incubation temperature was lowered from 37°C to 4°C. When exosome surface proteins were removed by treatment with proteinase K, or transport was measured in the presence of the carbohydrate competitor d-galactose or measured in the presence of excess unlabeled exosomes, transport rates decreased by 45% to 80% compared with controls. Treatment with an inhibitor of endocytosis, cytochalasin D, caused a 50% decrease in transport. When fluorophore-labeled exosomes were administered retro-orbitally, exosomes accumulated in liver, spleen, and lungs in mice. We conclude that human vascular endothelial cells transport bovine exosomes by endocytosis and propose that this is an important step in the delivery of dietary exosomes and their cargo to peripheral tissues.

The healing effect of bone marrow-derived stem cells in acute radiation syndrome

Objectives:To determine the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on regeneration of bone marrow and intestinal tissue and survival rate in experimental mice with acute radiation syndrome (ARS).Methods:Forty mice were randomly divided into two equal groups of A receiving no BMSC transplantation and B receiving BMSCs. BMSCs were isolated from the bone marrow and cultured in DMEM media. Both groups were irradiated with 10 Gy (dose rate 0.28 Gy/ min) 60CO during 35 minutes with a field size of 35×35 for all the body area. Twenty-four hours after γ irradiation, 150×103 cells of passage 5 in 150 µl medium were injected intravenously into the tail. Animals were euthanized one and two weeks after cell transplantation. They were evaluated histologically for any changes in bone marrow and intestinal tissues. The survival rate in mice were also determined.Results:A significant increase for bone marrow cell count and survival rate were observed in group B in comparison to group A. Histological findings denoted to a healing in sample tissues.Conclusion:BMSCs could significantly reduce the side effects of ARS and increase the survival rate and healing in injured tissue. As such their transplantation may open a window in treatment of patients with ARS.

In Vitro Effects of FBS and Ovarian Steroids on Osteoblast Viability

We evaluated the effects of different concentrations (0, 10‐8 M and 10‐7M) of progesterone (P4), testosterone (T) and estradiol (E2) on the osteoblast viability in vitro. Osteoblast lineages (OSTEO‐1) were cultured in 96‐well plates in DMEM medium a density of 5 x 103 cells/100 μL medium, with or without 10% fetal bovine serum (FBS). Cells were maintained at 37 ºC, with 5% CO2, for up to 48 hours. Cell viability was analyzed by MTT tetrazolium assay. The cells cultured with 10% FBS were more viable than those cultured without FBS. When all hormones were put together, the cell viability was reduced at the 10‐7M concentrations compared with the control and 10‐8 M. The viability of cells cultured without FBS was a) stimulated by E2 (10‐7 M and 10‐8 M (0.1048 ± 0.0227 and 0.1069 ± 0.0124, respectively)) compared with the control group (0.0566 ± 0.008); b) stimulated by P4 (10‐7 M (0.1088 ± 0.0124)) compared with the control group (0.0566 ± 0.008) and 10‐8 M (0.0924 ± 0.022); and c) stimulated by both concentrations of T (10‐7 M (0.0908 ± 0.0153) and 10‐8 M (0.0924 ± 0.0022)) compared with the control group (0.0566 ± 0.008). Our results demonstrated that FBS stimulated osteoblast viability, and P4 (10‐7 M), and both concentrations of T and E2 stimulated the viability of the cells cultured without FBS, suggesting that these steroid hormones may be important at the onset of osteoblast cells viability in vitro for up to 48 hours.

Abstract A17: Cellular genomics approaches to defining toxicity pathways of chemotherapeutic agents in immune cells

Abstract Background: While the role of the immune system in cancer development is known, its role in response to chemotherapeutic agents remains elusive. Interpatient variability in immune and chemotherapeutic cytotoxic responses is likely due to complex genetic differences. Through the use of a panel of genetically diverse mouse inbred strains, we developed a drug screening platform aimed at examining novel mechanisms underlying these chemotherapeutic cytotoxic responses on immune cells. Drug effects were investigated by comparing more selective chemotherapeutic agents such as BEZ235 and selumetinib against conventional cytotoxic agents, including doxorubicin and idarubicin. Our ultimate goal is to identify genetic biomarkers to determine which patients are most likely to have an advantageous risk-benefit ratio for a particular therapy. Methods: Splenocytes were isolated from 35 isogenic strains of mice using standard procedures. Of note, the splenocytes were not stimulated to avoid attributing genes to cellular stimulation rather than toxicity. Cells at a density of 100,000 cells per well with 100 μl media were incubated with compounds on a 10-point logarithmic dosing scale ranging from 0 to 100 μM (37°C, 5% CO2). At 4 hours post-treatment, cells were labeled with antibodies and physiological indicator dyes and fixed with 4% paraformaldehyde. Cellular phenotypes (e.g., viability, mitochondrial membrane potential, and caspase activity) were collected with the BD Biosciences FACSCanto II flow cytometer and analyzed with Flow Jo version X. Dose response curves with response normalized to the zero dose as a function of log concentration were subsequently generated using GraphPad Prism 5. SNPster and EMMA algorithms were used to perform genome-wide association mapping, providing precision (1 to 2 Mb) in localizing quantitative trait loci. Potential candidate genes for validation studies were prioritized using genome-wide significance, spleen expression data, haplotype structure, biological relevance, etc. Validation of the candidate gene App consisted of isolating splenocytes from App knockout mice with a C57BL/6J background and comparing their response to idarubicin with control C57BL/6J mice. Results: Phenotypes were quantified using flow cytometry, yielding interstrain variation for measured endpoints in different immune cells. Our flow cytometry assay produced nearly 16,000 data points that were used to generate dose response curves. The more targeted agents, BEZ-235 and selumetinib, were less toxic to immune cells than the anthracycline agents. Also, heritability for the viability of immune cells was higher (approximately 70 to 90%) for anthracyclines than the novel agents (approximately 35 to 60%), making them ideal for genetic analysis. Using genome-wide association studies, we identified loci that contributed to the sensitivity of doxorubicin and idarubicin in immune cells. We identified multiple QTL containing 35 promising candidate genes. Of particular interest, App encoding for amyloid beta precursor protein was identified under a peak on chromosome 16 (p = 5.01x10-8) in T-cells exposed to idarubicin. Dose response curves verified that T-cells in App knockout mice were more sensitive to idarubicin than those in C57BL/6J control mice (p = 0.01). Conclusion: Using a cellular screening approach, we identified and subsequently validated a gene candidate encoding for amyloid beta precursor protein in T-cells exposed to idarubicin. The literature has suggested a role for App in in vitro and in vivo cytotoxicity to anticancer agents; the overexpression of App enhances resistance, while the knockdown of this gene is deleterious to cell viability. In the future, we aim to perform mechanistic studies in primary and immortalized immune cells and, ultimately, to translate our findings to in vivo and human studies. Citation Format: Amber D. Frick, Kristy Richards, Yuri Fedoriw, Russell Thomas, Timothy Wiltshire. Cellular genomics approaches to defining toxicity pathways of chemotherapeutic agents in immune cells. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Drug Sensitivity and Resistance: Improving Cancer Therapy; Jun 18-21, 2014; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(4 Suppl): Abstract nr A17.

An innate immune system-mimicking, real-time biosensing of infectious bacteria.

An animal cell-based biosensor was investigated to monitor bacterial contamination in an unattended manner by mimicking the innate immune response. The cells (RAW 264.7 cell line) were first attached onto the solid surfaces of a 96-well microtiter plate and co-incubated in the culture medium with a sample that might contain bacterial contaminants. As Toll-like receptors were present on the cell membrane surfaces, they acted as a sentinel by binding to pathogen-associated molecular patterns (PAMPs) of any contaminant. Such biological recognition initiates signal transmission along various pathways to produce different proinflammatory mediators, one of which, tumor necrosis factor-α (TNF-α) was measured using an immunosensor. To demonstrate automated bacterium monitoring, a capture antibody specific for TNF-α was immobilized on an optical fiber sensor tip and then used to measure complex formation in a label-free sensor system (e.g., Octet Red). The sensor response time depended significantly on the degree of agitation of the culture medium, controlling the biological recognition and further autocrine/paracrine signaling by cytokines. The response, particularly under non-agitated conditions, was also influenced by the medium volume, revealing a local gradient change of the cytokine concentration and also acidity, caused by bacterial growth near the bottom surfaces. A biosensor system retaining 50 μL medium and not employing agitation could be used for the early detection of bacterial contamination. This novel biosensing model was applied to the real-time monitoring of different bacteria, Shigella sonnei, Staphylococcus aureus, and Listeria monocytogenes. They (<100 CFU mL(-1)) could be detected automatically within the working time. Such analysis was carried out without any manual handling regardless of the bacterial species, suggesting the concept of non-targeted bacterial real-time monitoring. This technique was further applied to real sample testing (e.g., with milk) to exemplify, for example, the food quality control process without using any additional sample pretreatment such as magnetic concentration.

Granzyme B secretion by human memory CD4 T cells is less strictly regulated compared to memory CD8 T cells.

BackgroundGranzyme B (GrzB) is a serine proteinase expressed by memory T cells and NK cells. Methods to measure GrzB protein usually involve intracellular (flow cytometry) and extracellular (ELISA and ELISpot) assays. CD8 T cells are the main source of GrzB during immunological reactions, but activated CD4 T cells deploy GrzB as well. Because GrzB is an important mediator of cell death, tissue pathology and disease, clarification of differences of GrzB expression and secretion between CD4 and CD8 T cells is important for understanding effector functions of these cells.ResultsMemory CD4 and memory CD8 T cells were purified from human peripheral blood of healthy donors, and production of GrzB was directly compared between memory CD4 and memory CD8 T cells from the same donors using parallel measurements of flow cytometry (intracellular GrzB), ELISpot (single cell secretion of GrzB), and ELISA (bulk extracellular GrzB). Memory CD8 T cells constitutively stored significantly more GrzB protein (~25%) compared to memory CD4 T cells as determined by flow cytometry (~3%), and this difference remained stable after 24 hrs of activation. However, measurement of extracellular GrzB by ELISA revealed that activated memory CD4 T cells secrete similar amounts of GrzB (~1,000 pg/ml by 1x105 cells/200 μl medium) compared to memory CD8 T cells (~600 pg/ml). Measurement of individual GrzB-secreting cells by ELISpot also indicated that similar numbers of activated memory CD4 (~170/1x105) and memory CD8 (~200/1x105) T cells secreted GrzB. Expression of CD107a further indicated that Grzb is secreted similarly by activated CD4 and CD8 T cells, consistent with the ELISA and ELISpot results. However, memory CD8 T cells expressed and secreted more perforin compared to memory CD4 T cells, suggesting that perforin may be less associated with GrzB function for memory CD4 T cells.ConclusionsAlthough measurement of intracellular GrzB by flow cytometry suggests that a larger proportion of CD8 T cells have higher capacity for GrzB production compared to CD4 T cells, ELISpot and ELISA show that similar numbers of activated CD4 and CD8 T cells secrete similar amounts of GrzB. Secretion of GrzB by activated CD8 T cells may be more tightly controlled compared to CD4 T cells.