Development and Validation of Deep Learning-Based Automated Detection of Cervical Lymphadenopathy in Patients with Lymphoma for Treatment Response Assessment: A Bi-institutional Feasibility Study.

The purpose is to train and evaluate a deep learning (DL) model for the accurate detection and segmentation of abnormal cervical lymph nodes (LN) on head and neck contrast-enhanced CT scans in patients diagnosed with lymphoma and evaluate the clinical utility of the DL model in response assessment. This retrospective study included patients who underwent CT for abnormal cervical LN and lymphoma assessment between January 2021 and July 2022. Patients were grouped into the development (n = 76), internal test 1 (n = 27), internal test 2 (n = 87), and external test (n = 26) cohorts. A 3D SegResNet model was used to train the CT images. The volume change rates of cervical LN across longitudinal CT scans were compared among patients with different treatment outcomes (stable, response, and progression). Dice similarity coefficient (DSC) and the Bland-Altman plot were used to assess the model's segmentation performance and reliability, respectively. No significant differences in baseline clinical characteristics were found across cohorts (age, P = 0.55; sex, P = 0.13; diagnoses, P = 0.06). The mean DSC was 0.39 ± 0.2 with a precision and recall of 60.9% and 57.0%, respectively. Most LN volumes were within the limits of agreement on the Bland-Altman plot. The volume change rates among the three groups differed significantly (progression (n = 74), 342.2%; response (n = 8), - 79.2%; stable (n = 5), - 8.1%; all P < 0.01). Our proposed DL segmentation model showed modest performance in quantifying the cervical LN burden on CT in patients with lymphoma. Longitudinal changes in cervical LN volume, as predicted by the DL model, were useful for treatment response assessment.

In vitro and in vivo genotoxicity evaluation of ALP1018, a nanomineral food supplement.

The use of nano-based dietary supplements is increasing around the world, as nanotechnology can help enhance nutrient bioavailability. ALP1018 is a newly developed iron-zinc complex supplement designed as a nanoformulation to improve the efficacy of iron and zinc supplementation. However, safety concerns have been raised, as there is no clear evaluation of ALP1018 toxicity. The goal of this study was to determine the potential mutagenicity and genotoxicity of ALP1018 through three standard screenings: the Ames test, which evaluates bacterial reverse mutations; the in vitro test of chromosomal aberration in Chinese hamster lung cells; and the in vivo micronucleus assay using ICR mice. ALP1018 showed no mutagenic effect, as no increase was observed in the presence or absence of metabolic activation (S9 mix) in revertant colonies on all the bacterial strains used in the Ames test. No structural chromosomal abnormalities were observed in the presence or absence of the S9 mix in mammalian cells used in the chromosomal aberration assay. In the micronucleus test, the frequency of micronucleated polychromatic erythrocytes was not significantly increased in mouse bone marrow cells. Based on these findings, we can conclude that ALP1018 is safe to use and has no mutagenic or genotoxic potential.

Self-assembled adipose-derived mesenchymal stem cells as an extracellular matrix component- and growth factor-enriched filler.

The clinical application of mesenchymal stem cells (MSCs) is attracting attention due to their excellent safety, convenient acquisition, multipotency, and trophic activity. The clinical effectiveness of transplanted MSCs is well-known in regenerative and immunomodulatory medicine, but there is a demand for their improved viability and regenerative function after transplantation. In this study, we isolated MSCs from adipose tissue from three human donors and generated uniformly sized MSC spheroids (∼100 µm in diameter) called microblocks (MiBs) for dermal reconstitution. The viability and MSC marker expression of MSCs in MiBs were similar to those of monolayer MSCs. Compared with monolayer MSCs, MiBs produced more extracellular matrix (ECM) components, including type I collagen, fibronectin, and hyaluronic acid, and growth factors such as vascular endothelial growth factor and hepatocyte growth factor. Subcutaneously injected MiBs showed skin volume retaining capacity in mice. These results indicate that MiBs could be applied as regenerative medicine for skin conditions such as atrophic scar by having high ECM and bioactive factor expression.

CD19 chimeric antigen receptor T cell therapy in leukemia xenograft mouse: Anti-leukemic efficacy, kinetics, and 4-week single-dose toxicity.

CD19 Chimeric antigen receptor T (CAR-T) cell therapy has shown a promising response rate for relapsed/refractory B-cell malignancies. However, serious side effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome arose in early case reports. Though several preclinical and clinical studies of CAR-T cell therapy have been reported, there is a lack of toxicological assessments. This study was carried out as a preclinical assessment of CD19 CAR-T cell therapy, including the anti-leukemic efficacy, kinetics in peripheral blood, and 4-week single-dose toxicity evaluation in leukemia xenograft mice. Leukemia xenograft mice model was established by injecting 1.0 × 105 cells/mouse of luciferase-labeled human B cell acute lymphoblastic leukemia (B-ALL) cell line via the tail vein, and after 3 days, 2.0 or 4.0 × 106 cells/mouse of CD19 CAR-T cells were injected intravenously. CD19 CAR-T cells showed significant anti-leukemic efficacy, showing inhibition of tumor progression in the bioluminescence-based in-vivo imaging system. In the kinetics study using qPCR, CAR-T cells peaked in peripheral blood on day 60 in males and day 30 in females. In a 4-week single-dose toxicity study, CD19 CAR-T cell injected groups showed no mortality and toxicological signs, or changes in body weight, food/water consumption, hematology, clinical chemistry, organ weights, and histopathology compared to control groups. These results suggested that 4.0 × 106 cells/mouse of CD19 CAR-T cells were effective in B-ALL xenograft mice without serious side effects, so the no-observed adverse effect level (NOAEL) was estimated to be higher than 4.0 × 106 cells/mouse, under the condition examined in the current study.

Tagmentation-based analysis reveals the clonal behavior of CAR-T cells in association with lentivector integration sites.

Integration site (IS) analysis is essential in ensuring safety and efficacy of gene therapies when integrating vectors are used. Although clinical trials of gene therapy are rapidly increasing, current methods have limited use in clinical settings because of their lengthy protocols. Here, we describe a novel genome-wide IS analysis method, "detection of the integration sites in a time-efficient manner, quantifying clonal size using tagmentation sequencing" (DIStinct-seq). In DIStinct-seq, a bead-linked Tn5 transposome is used, allowing the sequencing library to be prepared within a single day. We validated the quantification performance of DIStinct-seq for measuring clonal size with clones of known IS. Using ex vivo chimeric antigen receptor (CAR)-T cells, we revealed the characteristics of lentiviral IS. We then applied it to CAR-T cells collected at various times from tumor-engrafted mice, detecting 1,034-6,233 IS. Notably, we observed that the highly expanded clones had a higher integration frequency in the transcription units and vice versa in genomic safe harbors (GSH). Also, in GSH, persistent clones had more frequent IS. Together with these findings, the new IS analysis method will help to improve the safety and efficacy of gene therapies.

Nonclinical safety evaluation of food colorant lac dye via systematic toxicity profiling with assessment of in vivo antigenic potential.

Lac dye is a natural colorant derived mainly from the insect Kerria lacca (Kerr) and has been used in food and beverage as a red-coloring additive. Despite its increasing use for human consumption as an alternative for allergy-associated cochineal, its toxicity profile remained incomplete to sufficiently assess its safety for the intended use. In this study, we evaluated systemic and genetic toxicity by performing acute and subacute oral toxicity studies in Sprague-Dawley (SD) rats using highly purified lac dye (LD) formulated in water and a battery of genotoxicity tests, respectively. To assess antigenic potentials, we carried out an in vivo passive cutaneous anaphylaxis test. A single dose of LD did not cause mortality at 5000 mg/kg body weight (BW), setting oral LD50 of >5000 mg/kg BW in SD rats. In the 90-day study, transient salivation without accompanying histopathological lesions in the salivary glands in 200 and 500 mg/kg BW groups and red-purple pigmentation on the surface of femora and skulls in 500 mg/kg groups were observed as nonadverse effects associated with LD, and no adverse effect was detected in all of the parameters examined, establishing a 500 mg/kg BW as no-observed-adverse-effect-level (NOAEL). Furthermore, LD was not mutagenic nor clastogenic in the genotoxicity tests. When tested for antigenicity, LD did not induce anaphylactic skin responses as opposed to the positive reaction by ovalbumin, suggesting a lack of antigenicity. Taken together, these findings provide extended toxicity information on LD with direct evidence supporting the lack of antigenicity, providing essential guidance for its safe use in humans.

Efficacy and safety evaluation of black ginseng (Panax ginseng C.A. Mey.) extract (CJ EnerG): broad spectrum cytotoxic activity in human cancer cell lines and 28-day repeated oral toxicity study in Sprague-Dawley rats.

BACKGROUND: Ginseng (Panax ginseng C.A. Mey.) has been used as a valuable ingredient in traditional medicine for thousands of years mostly in Asian countries due to its therapeutic effects in various diseases. Among the processed ginseng products, black ginseng is produced by a repeated steaming and drying process of ginseng roots and has been known for its superior efficacy based on high accumulation of minor ginsenosides as recently discovered. Despite its popularity and increasing use, the toxicity information on black ginseng still remained largely lacking, raising safety concerns. This study was therefore carried out to determine the repeated oral toxicity of black ginseng extract (BGE; CJ EnerG) with evaluation of cytotoxic activity as validation of its pharmacological activity for toxicity testing. METHODS: Prior to the toxicity test, we examined the cytotoxicity of BGE in six cancer cell lines derived from distinct human tissues in comparison with red ginseng extract (RGE), ginsenosides Rg5 and 20(S)-Rg3, and then assessed 28-day repeated oral toxicity in Sprague-Dawley (SD) rats using daily administration of up to 2000 mg/kg BGE. RESULTS: BGE showed higher cytotoxicity than RGE in all the cell lines used in this study. Interestingly, the efficacy of BGE closely resembled the cytotoxic pattern of Rg5, suggesting Rg5 as the main effector in the cytotoxic activity of BGE. During the toxicity study, BGE-treated groups showed no noticeable abnormality in clinical signs, body weight gain, food and water consumption and urinalysis. Furthermore, hematological, serum biochemical and histopathological analyses did not find any BGE-related toxicity. CONCLUSION: Our findings demonstrated that BGE has broad-spectrum in vitro cytotoxic activity, and that NOAEL of BGE in SD rats is > 2000 mg/kg, providing the essential safety information for human consumption.

Genotoxicity Evaluation of Termite Mushroom, Termitomyces albuminosus (Agaricomycetes), Powder.

Termitomyces albuminosus, also known as termite mushroom, is a palatable mushroom with therapeutic effects that has been used as a food and folk medicinal ingredient. Recent studies revealed that T. albuminosus contains pharmacologically active factors that exert anti-inflammatory, antihyperlipidemic, antidiabetic, hepatoprotective, and neuritogenic activities, leading to its increasing popularity as a supplement among the general public. Despite the increase in its use, however, lack of knowledge on the toxicity of T. albuminosus has raised safety concerns. In this study, we systemically evaluated the genotoxicity of T. albuminosus powder (TAP) by testing its potential in generating bacterial reverse mutation, in vitro chromosome aberration, and in vivo micronuclei. TAP did not increase revertant colonies in the bacterial reverse mutation test nor the number of cells with aberrant chromosomes at 5000 µg/plate and micronucleus-containing polychromatic erythrocytes at 2000 mg/kg body weight in mice, indicating that TAP is not mutagenic nor clastogenic. Our results, together with the previous data from the general toxicity studies, indicate that TAP is safe for human consumption.

Safety Assessment of Acer tegmentosum Maxim. Water Extract: General Toxicity Studies in Sprague-Dawley Rats and Beagle Dogs With Re-evaluation of Genotoxic Potentials.

Acer t egmentosum Maxim., commonly known as Manchurian stripe maple, is a deciduous tree belonging to the family of Aceraceae and has been traditionally used in folk medicine for its remedial effects in liver diseases and traumatic bleedings. With a growing body of experimental evidence for its pharmacological efficacies, such as neuroprotective, hepatoprotective, antioxidant, and anti-inflammatory activities, A. tegmentosum has gradually gained popularity as a health supplement and functional food. However, the large part of essential toxicity information still remained lacking despite the possibility of mutagenic potentials as previously suggested, posing safety concerns for human consumption. In this study, we evaluated 90-day repeated oral toxicity of A. tegmentosum Maxim. water extract (ATWE) in SD rats with acute toxicity assessment in beagle dogs, and reevaluated genotoxicity using a combination of in vitro and in vivo assays. During the oral study period, ATWE did not cause toxicity-related clinical signs and mortality in rodents without adverse effects observed in the analysis of hematology, serum biochemistry, and histopathology, establishing >5,000 mg/kg BW as the NOAEL. In addition, doses up to 5,000 mg/kg BW did not cause acute toxicity in beagle dogs. When assessed for genotoxicity using bacterial reverse mutation, chromosome aberration, and micronucleus formation, ATWE showed lack of mutagenicity and clastogenicity. These results demonstrated that AWTE was safe in the present preclinical study for systemic toxicity and genotoxicity at the tested doses, providing a guideline for safe use in humans.

Nonclinical toxicology studies with sodium taurodeoxycholate: acute and subacute toxicity in dogs.

Sodium taurodeoxycholate (TDCA) has been investigated for various inflammatory disorders such as sepsis. We recently evaluated nonclinical safety profile of TDCA using rats infused intravenously. As a series of preclinical safety investigations, we further conducted toxicity studies with TDCA delivered to dogs via intravenous administration under Good Laboratory Practice regulation in this study. In dose range-finding study (dose escalation study), dogs given with TDCA at a dose of 150 mg/kg showed marked changes in clinical signs, hematology, and serum biochemistry. And biochemical markers of liver damage and local skin lesions were observed following intravenous infusion of 100 mg/kg TDCA, suggesting that 100 mg/kg was chosen as the highest dose of TDCA for 4-week repeated-dose toxicity study using dogs. Despite no treatment-related significant changes in body weight, food consumption, ophthalmoscopy, and urinalysis, skin lesions were observed at the injection site of animals administered with higher than 50 mg/kg of TDCA along with biochemical and histopathological changes associated with liver injury. However, most of off-target effects were found to be reversible since these were recovered after stopping TDCA infusion. These findings indicate that the no-observed-adverse-effect-level (NOAEL) for TDCA in dogs was considered to be 5 mg/kg/d. Taken together, our results provide important toxicological profiles regarding the safe dose of TDCA for drug development or clinical application.

Evaluation of acute and subacute toxicity of sodium taurodeoxycholate in rats.

Taurodeoxycholate (TDCA) inhibits various inflammatory responses suggesting potential clinical application. However, the toxicity of TDCA has not been evaluated in detail in vivo. We investigated the acute toxicity and 4-week repeated-dose toxicity of TDCA following intravenous infusion under Good Laboratory Practice regulations. In the sighting study of acute toxicity, one of two rats (one male and one female) treated with 300 mg/kg TDCA died with hepatotoxicity, suggesting that the approximate 50% lethal dose of TDCA is 300 mg/kg. Edema and discoloration were observed at the injection sites of tails when rats were infused with 150 mg/kg or higher amount of TDCA once. In 4-week repeated-dose toxicity study, no treatment-related mortality or systemic changes in hematology and serum biochemistry, organ weights, gross pathology, or histopathology were observed. However, the tail injection site showed redness, discharge, hardening, and crust formation along with histopathological changes such as ulceration, edema, fibrosis, and thrombosis when rats were infused with 20 mg/kg TDCA. Taken together, TDCA induced no systemic toxicity or macroscopic lesions at the injection site at a dose of 10 mg/kg/day, which is 33 times higher than the median effective dose observed in a mouse sepsis model. These findings suggest that TDCA might have a favorable therapeutic index in clinical applications.

In vivo and in vitro safety evaluation of fermented Citrus sunki peel extract: acute and 90-day repeated oral toxicity studies with genotoxicity assessment.

BACKGROUND: Citrus sunki Hort. ex Tanaka peel has been traditionally used as an ingredient in folk medicine due to its therapeutic effects on promotion of splenic health and diuresis as well as relief of gastrointestinal symptoms. Although a growing interest in health-promoting natural products and the development of highly concentrated products have facilitated consumption of C. sunki peel, its safety assessment has not been explored, posing a potential health risk. In this study, we carried out a series of systemic and genetic toxicity tests on fermented C. sunki peel extract (FCPE) to provide the essential information required for safe use in human. METHODS: We conducted acute and 90-day repeated oral toxicity studies in Sprague-Dawley rats to evaluate systemic toxicity, and three genotoxicity assays to measure bacterial mutation reversion, cellular chromosome aberration and in vivo micronucleus formation. RESULTS: Single oral administration of FCPE did not cause any clinical signs and lethality in all animals, establishing LD50 to be over 2000 mg/kg BW. Repeated administration of up to 2000 mg/kg BW FCPE for 90 days revealed no test substance-related toxicity as demonstrated in analysis of body weight gain, food/water intake, blood, serum biochemistry, organ weight and histopathology, collectively determining that the no-observable-adverse-effect-level of FCPE is over 2000 mg/kg BW. In addition, we detected no mutagenicity and clastogenicity in FCPE at 5000 µg/plate for the in vitro assays and 2000 mg/kg BW for the in vivo micronucleus test. CONCLUSION: FCPE did not cause systemic and genetic toxicity in our model systems at the tested dose levels. These results suggest a guideline for safe consumption of C. sunki peel in human.

Toxicologic Evaluation for Amorphous Silica Nanoparticles: Genotoxic and Non-Genotoxic Tumor-Promoting Potential.

Amorphous silica nanoparticles (SiO2NPs) have been widely used in medicine including targeted drug/DNA delivery, cancer therapy, and enzyme immobilization. Nevertheless, SiO2NPs should be used with caution due to safety concerns associated with unique physical and chemical characteristics. The objective of this study was to determine the effects of SiO2NPs on genotoxic and non-genotoxic mechanisms associated with abnormal gap junctional intercellular communication (GJIC) in multistage carcinogenesis. The SiO2NPs exhibited negative responses in standard genotoxicity tests including the Ames test, chromosome aberration assay, and micronucleus assay. In contrast, the SiO2NPs significantly induced DNA breakage in comet assay. Meanwhile, SiO2NPs inhibited GJIC based on the results of scrape/loading dye transfer assay for the identification of non-genotoxic tumor-promoting potential. The reduction in expression and plasma membrane localization of Cx43 was detected following SiO2NP treatment. Particularly, SiO2NP treatment increased Cx43 phosphorylation state, which was significantly attenuated by inhibitors of extracellular signal-regulated kinases 1/2 (ERK1/2) and threonine and tyrosine kinase (MEK), but not by protein kinase C (PKC) inhibitor. Taken together, in addition to a significant increase in DNA breakage, SiO2NP treatment resulted in GJIC dysregulation involved in Cx43 phosphorylation through the activation of mitogen-activated protein kinase (MAPK) signaling. Overall findings of the genotoxic and non-genotoxic carcinogenic potential of SiO2NPs provide useful toxicological information for clinical application at an appropriate dose.

Differential manifestation of ocular phenotypes in TALEN-mediated p19arf knockout FVB/N and C57BL/6J mouse lines.

BACKGROUND: p19arf, primarily known as a tumor suppressor, has also been reported to play an essential role in normal development of mouse eyes. Consistently, lack of p19arf has been associated with ocular defects, but the mixed background of the knockout (KO) mouse strain used raised a concern on the accuracy of the phenotypes observed in association with the targeted gene due to genetic heterogeneity. OBJECT: We carried out a study to investigate into the effect of genetic background on the manifestation of p19arf KO associated phenotypes. METHODS: We characterized the phenotypes of novel p19arf KO mouse lines generated in FVB/N and C57BL/6J using a transcription activator-like effector nuclease (TALEN) system in comparison to the reported phenotypes of three other p19arf-deficient mouse lines generated using homologous recombination. RESULTS: Ninety-five percent of FVB/N-p19arf KO mice showed ocular opacity from week 4 after birth which worsened rapidly until week 6, while such abnormality was absent in C57BL/6J-p19arf KO mice up to the age of 26 weeks. Histopathological analysis revealed retrolental masses and dysplasia in the retinal layer in FVB/N-p19arf KO mice from week 4. Besides these, both strains developed normally from birth to week 26 without increased tumorigenesis except for a subcutaneous tumor found in a C57BL/6J-p19arf KO mouse. CONCLUSION: Our findings demonstrated surprisingly variable manifestation of p19arf-linked phenotypes between FVB/N and C57BL/6J mice, and furthermore between our mouse lines and the established lines, indicating a critical impact of genetic background on functional study of genes using gene targeting strategies in mice.

Preclinical study of safety of Dendropanax morbifera Leveille leaf extract: General and genetic toxicology.

ETHNOPHARMACOLOGY RELEVANCE: Dendropanax morbifera Leveille (DM) has been used in traditional medicines for infectious and skin diseases, and dysmenorrhea. It exhibits a diverse therapeutic potential including anti-cancer, anti-thrombotic, anti-diabetic, anti-oxidant, and anti-inflammatory activities. AIM OF THE STUDY: Despite promising health benefits of DM, knowledge of its potential adverse effects is very limited. The current study focused on the investigation of subchronic toxicity and genotoxicity of extract obtained from DM according to the test guidelines published by the Organization for Economic Cooperation and Development. MATERIALS AND METHODS: We conducted a toxicological evaluation of DM extracts using 14-day repeated-dose toxicity study and 13-week repeated-dose toxicity study in Sprague-Dawley rats administered orally at doses of 500, 1000, or 2000 mg/kg/day. The clastogenicity of DM extract was also evaluated by in vitro chromosome aberration assay and in vivo micronucleus assay. RESULTS: Assessment of subchronic toxicity of DM extract by oral administration in rats revealed unremarkable treatment-related findings with respect to food/water consumption, body weight, mortality, urinalysis, hematology, serum biochemistry, necropsy, organ weight and histopathology at doses of 500, 1000, and 2000 mg/kg. Accordingly, the level of no-observed-adverse-effect for DM extract in 13-week subchronic toxicity study was considered to be 2000 mg/kg/day in rats. The data observed from in vitro chromosome aberration assay and in vivo micronucleus assay exclude any clastogenicity of DM extract. CONCLUSION: The results suggest that the oral consumption of DM extract has no adverse effects in humans and represents a safe traditional medicine.

Assessment of acute, 14-day, and 13-week repeated oral dose toxicity of Tiglium seed extract in rats.

BACKGROUND: Seed of mature Croton tiglium Linne, also known as Tiglium seed (TS), has been widely used as a natural product due to its several health beneficial properties including anti-tumor and antifungal activities. Despite its ethnomedicinal beneficial properties, toxicological information regarding TS extract, especially its long-term toxicity, is currently limited. Therefore, the objective of the present study was to evaluate acute and subchronic toxicity of TS extract in rats after oral administration following test guidelines of the Organization for Economic Cooperation and Development (OECD). METHODS: Toxicological properties of TS extract were evaluated by toxicity assays to determine its single-dose acute toxicity (125, 250, 500, 1000, or 2000 mg/kg), 14-day repeated-dose toxicity (125, 250, 500, 1000, or 2000 mg/kg) and 13-week repeated-dose toxicity (31.25, 62.5, 125, 250, and 500 mg/kg) in Sprague-Dawley rats and F344 rats. Hematological, serum biochemical, and histopathological parameters were analyzed to determine its median lethal dose (LD50) and no-observed-adverse-effect-level (NOAEL). RESULTS: Oral single dose up to 2000 mg/kg of TS extract resulted in no mortalities or abnormal clinical signs. In 13-week toxicity study, TS extract exhibited no dose-related changes (mortality, body weight, food/water consumption, hematology, clinical biochemistry, organ weight, or histopathology) at dose up to 500 mg/kg, the highest dosage level suggested based on 14-day repeat-dose oral toxicity study. CONCLUSION: Acute oral LD50 of TS extract in rats was estimated to be greater than 2000 mg/kg. NOAEL of TS extract administered orally was determined to be 500 mg/kg/day in both male and female rats. Results from these acute and subchronic toxicity assessments of TS extract under Good Laboratory Practice regulations indicate that TS extract appears to be safe for human consumption.

In vitro and in vivo safety studies of cinnamon extract (Cinnamomum cassia) on general and genetic toxicology.

Cinnamomum cassia has been widely used as a natural product to treat diseases in Asia due to its diverse pharmacological functions including anti-inflammatory, anti-oxidant, anti-microbial, anti-diabetic, and anti-tumor effects. Despite its ethnomedicinal benefits, little information regarding its toxicity is currently available. The aim of this study was to evaluate its potential long-term toxicity and genotoxicity in compliance with test guidelines of the Organization for Economic Cooperation and Development. A 13-week repeat-dose oral toxicity study revealed that body weights of rats were normal after receiving cinnamon extract at up to 2000 mg/kg. High-dose intake of cinnamon extract (2000 mg/kg) showed potential nephrotoxicity and hepatotoxicity to both males and females as evidenced by obvious increases of kidney/liver weight along with a small but statistically elevation of total cholesterol level. Overall findings from genetic toxicity testing battery including Ames test, in vitro mammalian cell micronucleus assay, and in vivo bone marrow micronucleus assay indicated that cinnamon extract was not mutagenic or clastogenic. In conclusion, cinnamon extract may possess potential nephrotoxicity and hepatotoxicity at dose higher than its recommended daily safe dose. Further study is needed to clarify the mechanism involved in its induction of liver and kidney injury.

Enzymatic extract from Ecklonia cava: Acute and subchronic oral toxicity and genotoxicity studies.

Ecklonia cava (EC) is known to have antioxidant, anti-inflammatory, antidiabetic, and anticancer properties. Despite its wide use and beneficial properties, comprehensive toxicological information regarding EC extract is currently limited. Therefore, the purpose of this study was to investigate acute toxicity, subchronic toxicity, and genotoxicity of enzymatic EC extract according to test guidelines published by Organization for Economic Cooperation and Development. The acute oral LD50 values of this EC extract administered to rats and dogs were estimated to be more than 3000 mg/kg BW. In an oral 13-week toxicity study, changes in body weights of rats exposed to the EC extract up to 3000 mg/kg BW were found to be normal. In addition, repeated doses of EC extract failed to influence any systematic parameters of treatment-related toxic symptoms such as food/water consumption, mortality, urinalysis, hematology, serum biochemistry, organ weight, or histopathology. These results indicated that the no-observed-adverse-effect level for the EC extract was 3000 mg/kg/day for male and female rats. Data obtained from Ames test, chromosome aberration assay, and micronucleus assay indicated that EC extract was not mutagenic or clastogenic. Taken together, these results support the safety of enzymatic EC extract as a potential therapeutic for human consumption against various diseases.

CRISPR/Cas9-mediated knockout of Rag-2 causes systemic lymphopenia with hypoplastic lymphoid organs in FVB mice.

Recombination activating gene-2 (RAG-2) plays a crucial role in the development of lymphocytes by mediating recombination of T cell receptors and immunoglobulins, and loss of RAG-2 causes severe combined immunodeficiency (SCID) in humans. RAG-2 knockout mice created using homologous recombination in ES cells have served as a valuable immunodeficient platform, but concerns have persisted on the specificity of RAG-2-related phenotypes in these animals due to the limitations associated with the genome engineering method used. To precisely investigate the function of RAG-2, we recently established a new RAG-2 knockout FVB mouse line (RAG-2 -/-) manifesting lymphopenia by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease. In this study, we further characterized their phenotypes focusing on histopathological analysis of lymphoid organs. RAG-2 -/- mice showed no abnormality in development compared to their WT littermates for 26 weeks. At necropsy, gross examination revealed significantly smaller spleens and thymuses in RAG-2 -/- mice, while histopathological investigation revealed hypoplastic white pulps with intact red pulps in the spleen, severe atrophy of the thymic cortex and disappearance of follicles in lymph nodes. However, no perceivable change was observed in the bone marrow. Moreover, our analyses showed a specific reduction of lymphocytes with a complete loss of mature T cells and B cells in the lymphoid organs, while natural killer cells and splenic megakaryocytes were increased in RAG-2 -/- mice. These findings indicate that our RAG-2 -/- mice show systemic lymphopenia with the relevant histopathological changes in the lymphoid organs, suggesting them as an improved Rag-2-related immunodeficient model.

CRISPR/Cas9-mediated knockout of CD47 causes hemolytic anemia with splenomegaly in C57BL/6 mice.

CD47 (integrin-associated protein), a multi-spanning transmembrane protein expressed in all cells including red blood cells (RBCs) and leukocytes, interacts with signal regulatory protein α (SIRPα) on macrophages and thereby inhibits phagocytosis of RBCs. Recently, we generated a novel C57BL/6J CD47 knockout (CD47 -/- hereafter) mouse line by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease, and here report their hematological phenotypes. On monitoring their birth and development, CD47 -/- mice were born viable with a natural male-to-female sex ratio and normally developed from birth through puberty to adulthood without noticeable changes in growth, food/water intake compared to their age and sex-matched wild-type littermates up to 26 weeks. Hematological analysis revealed a mild but significant reduction of RBC counts and hemoglobin in 16 week-old male CD47 -/- mice which were aggravated at the age of 26 weeks with increased reticulocyte counts and mean corpuscular volume (MCV), suggesting hemolytic anemia. Interestingly, anemia in female CD47 -/- mice became evident at 26 weeks, but splenomegaly was identified in both genders of CD47 -/- mice from the age of 16 weeks, consistent with development of hemolytic anemia. Additionally, helper and cytotoxic T cell populations were considerably reduced in the spleen, but not in thymus, of CD47 -/- mice, suggesting a crucial role of CD47 in proliferation of T cells. Collectively, these findings indicate that our CD47 -/- mice have progressive hemolytic anemia and splenic depletion of mature T cell populations and therefore may be useful as an in vivo model to study the function of CD47.