A collaborative study to establish the second national standard for hepatitis B immunoglobulin in Korea.

This study aimed to establish a second national standard for hepatitis B immunoglobulin (HBIG) that can be used for potency assays of hepatitis B and normal immunoglobulin. The candidate material was manufactured using a process approved as Good Manufacturing Practice. The freeze-dried candidate preparation was tested for physicochemical and biological properties, including pH, residual moisture, molecular size distribution, and potency. A collaborative study was performed involving four laboratories, including the National Institute of Food and Drug Safety Evaluation, as an official national control laboratory in Korea and manufacturers. The potency was calibrated against the second international standard for HBIG using two enzyme immunoassays: enzyme-linked immunosorbent assay and electrochemiluminescence immunoassay. Results from 240 assays were obtained from four laboratories, and combined potency estimates were obtained by calculating the geometric means. Intra- and inter-laboratory variability showed acceptable geometric coefficients of variation of 1.3-6.0 and 3.2-3.6%, respectively. The candidate preparation showed satisfactory stability in accelerated thermal degradation and real-time stability tests. Based on these results, the potency value of 105 IU/vial was assigned (95% confidence intervals: 100.0-109.2 IU/vial), and it was deemed suitable to serve as the Korean national standard for HBIG.

Assessment of penetration of quantum dots through in vitro and in vivo human skin using the human skin equivalent model and the tape stripping method.

Quantum dots (QDs) are rapidly emerging as an important class of nanoparticles (NPs) with potential applications in medicine. However, little is known about penetration of QDs through human skin. This study investigated skin penetration of QDs in both in vivo and in vitro human skin. Using the tape stripping method, this study demonstrates for the first time that QDs can actually penetrate through the stratum corneum (SC) of human skin. Transmission electron microscope (TEM) and energy diverse X-ray (EDX) analysis showed accumulation of QDs in the SC of a human skin equivalent model (HSEM) after dermal exposure to QDs. These findings suggest possible transdermal absorption of QDs after dermal exposure over a relatively long period of time.

Role of interleukin-23 in the development of nonallergic eosinophilic inflammation in a murine model of asthma.

Nonallergic eosinophilic asthma (NAEA) is a clinically distinct subtype of asthma. Thus far, the pathophysiologic mechanisms underlying NAEA have not been fully elucidated. This study aimed to determine the role of IL-23 in the pathogenesis of NAEA. We developed a murine model of NAEA using recombinant IL-23 (rIL-23) plus a nonspecific airway irritant [polyinosinic-polycytidylic acid (polyI:C) or diesel exhaust particles (DEPs)] and investigated whether IL-23 plays an important role in the development of NAEA. Intranasal administration of rIL-23 (0.1 µg/mouse) plus polyI:C (0.01 µg/mouse) or DEPs (10 µg/mouse) without allergen resulted in methacholine bronchial hyperresponsiveness and eosinophilic airway inflammation in mice, which are characteristic features of NAEA. rIL-23 plus a low dose nonspecific airway irritants induced the release of innate cytokines from airway epithelium, including IL-33, thymic stromal lymphopoietin and IL-1ß; these factors activated types 2 and 3 innate lymphoid cells (ILC2s and ILC3s). ILC2s and ILC3s, but not CD4+ T cells (i.e., adaptive immune cells), were important in the development of NAEA. In addition, we observed that IL-23 receptor expressions increased in airway epithelial cells, which suggests the existence of a positive autocrine loop in our murine model of NAEA. To our knowledge, this is the first report in which administration of rIL-23 plus a nonspecific airway irritant (polyI:C or DEPs) without allergen resulted in features of NAEA in mice similar to those found in humans. IL-23 may constitute a therapeutic target for NAEA in humans.

Analysis of Individual Case Safety Reports of Severe Cutaneous Adverse Reactions in Korea.

PURPOSE: Despite morbidities and fatalities, nationwide epidemiologic data for severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS), are not widely available. We aimed to investigate SCAR epidemiology over the last two decades in Korea. MATERIALS AND METHODS: We analyzed individual case safety reports (ICSRs) of SCARs in the Korea Adverse Event Reporting System from 1988 to 2013. Administered drugs, demographic profiles, and causality assessment according to the World Health Organization-Uppsala Monitoring Center system were analyzed. RESULTS: A total of 755 SCAR cases (508 SJS/TEN, 247 DRESS) were reported. The number of SCAR ICSRs has been increasing with increasing ICSRs for overall adverse drug events. Since 2010, the number of SCAR ICSRs has increased up to 100 cases/year. Allopurinol was the most common causative drug (SJS/TEN: 10.2%; DRESS: 11.3%; SCAR ICSRs: 10.6%), followed by carbamazepine (SJS/TEN: 8.7%; DRESS: 9.7%; SCAR ICSRs: 8.6%). Regarding drug groups, antiepileptics (19.5%) and antibiotics for systemic use (12.7%) were common causative drug groups. Twenty SCAR-related deaths were recorded. Antibacterials were the most common causes of deaths (8 cases), followed by antiepileptics (5 cases). The potential risk of SCARs was not specified in the drug information leaflet for 40.2% of drugs causing SJS/TEN and 82.5% causing DRESS syndrome in Korea. CONCLUSION: The number of SCAR ICSRs has increased rapidly with recent active pharmacovigilance programs in Korea. Allopurinol and antiepileptics are the most common individual and categorical causative agents, respectively.

Comparative evaluation of alkylphenolic compounds on estrogenic activity in vitro and in vivo.

This study was undertaken to compare the sensitivity of screening test methods and to investigate the structure-activity relationships of the estrogenic activity of alkylphenolic compounds (APs) using in vitro and in vivo assays. Two in vitro systems, MCF-7 cell proliferation (E-screen assay) and competitive binding assay to estrogen receptor (ER), were selected to evaluate the estrogenic effects. Uterotrophic assay and Calbindin-D9K (CaBP9K) mRNA expression were also examined in ovariectomized Sprague-Dawley female rats. A series of APs with various alkyl groups were examined, namely, 4-propylphenol, 4-butylphenol, 4-t-butylphenol, 4-pentylphenol, 4-nonylphenol, 4-octylphenol, 4-t-octylphenol, and 4-phenylphenol, and 17beta-estradiol (E2) was used as a positive control. In the E-screen assay, E2 was found to induce maximum proliferation of MCF-7 cells at 1 nM. Among the APs, 4-t-octylphenol and 4-nonylphenol were found to be considerably more potent than any other compound and estrogenic effects were detectable at 1 and 10 microM, respectively. 4-t-Octylphenol and 4-nonylphenol inhibited the binding of E2 to the ER of MCF-7 cells in a competitive ER binding assay. The uterotrophic effects to APs (10, 50, 200, and 400 mg/kg/d) were compared to E2 (1 microg/kg) in ovariectomized rats after treatment for 3 d. 4-Nonylphenol, 4-t-octylphenol, and 4-phenylphenol produced dose-dependent increases in the uterine weights of ovariectomized rats. In the CaBP-9K mRNA expression test, CaBP-9K mRNA levels were detected in the uteri of ovariectomized rats treated with 4-pentylphenol (400 mg/kg), 4-nonylphenol, 4-phenylphenol (200 and 400 mg/kg), and 4-t-octylphenol (50 mg/kg and above), respectively. In the dot blot assay, CaBP-9K mRNA levels were significantly increased in rats exposed to 4-t-octylphenol (200 and 400 mg/kg), 4-pentylphenol, 4-nonylphenol, and 4-phenylphenol (400 mg/kg), respectively. Among the APs, compounds with bulky alkyl groups or higher carbon numbers possessed higher estrogenic capacity. In addition, the pattern of CaBP-9K expression correlated with that of the 3-d uterotrophic assay. Therefore, our results suggest that the CaBP-9K gene might be used as a potential biomarker for the screening of endocrine disruptors.

Effects of dibutyl phthalate and monobutyl phthalate on cytotoxicity and differentiation in cultured rat embryonic limb bud cells; protection by antioxidants.

This present study was undertaken to examine the effects of DBP and its metabolite mono-n-butyl phthalate (MBuP) on cytotoxicity and differentiation in cultured rat embryonic limb bud cells. When limb bud cells extracted from rats on gestation d 12.5 were treated with DBP or MBuP for 96 h, induction of cytotoxicity and inhibition of cell differentiation were observed in a concentration-dependent manner. However, MBuP elicited a toxic effect at higher concentrations than DBP. The IC50 values of DBP for cytotoxicity (measured by neutral red uptake) and cell differentiation (measured by alcian blue staining) were 25.54 microg/ml (91.75 microM) and 21.21 microg/ml (76.20 microM), respectively. The IC50 values of MBuP for cytotoxicity and cell differentiation were 307.24 microg/ml (1.38 mM) and 142.61 microg/ml (0.64 mM), respectively. in order to determine whether free radicals are related to induction of cytotoxicity and inhibition of differentiation by DBP in limb bud cells, DBP was coadministered with several antioxidants, including catalase and vitamin E acetate to limb bud cells. Cotreatment with catalase and vitamin E acetate decreased induction of cytotoxicity and inhibition of differentiation by DBP in limb bud cells. However, these compounds did not show any protective effect against MBuP. Results indicate that DBP and MBuP induced developmental toxicity in rat embryonic limb bud cells and suggest that this effect of DBP might be exerted through oxidative stress.

Polybrominated Diphenyl Ethers Orally Administration to Mice Were Tansferred to Offspring during Gestation and Lactation with Disruptions on the Immune System.

BACKGROUND: The present study was undertaken to examine the immunological effects of pentabrominated diphenyl ether (penta-BDE) and decabrominated diphenyl ether (deca-BDE) on the immune system of the dams and the developmental immune system of the offsprings. METHODS: In this study, mated female C57BL/6J mice were orally administered penta-BDE, deca-BDE or corn oil for 5 weeks, from gestational day 6 to lactational day 21. RESULTS: The body weight of PND21 exposed to penta-BDE was significantly decreased relative to control mice, but that of post-natal day 63 (PND63) were recovered. Orally dosed dams with penta-BDE had significantly smaller absolute and relative spleen masses than control mice. Absolute and relative spleen and thymus masses of PND21 exposed to penta-BDE were significantly decreased over control. The exposure of dams and PND21 with penta-BDE reduced the number of splenocytes and thymocytes. As results of hematologic analysis, percentage WBC and percentage neutrophils increased in dams with deca-BDE. Splenic T cell proliferation in dams and PND21 exposed to penta-BDE was increased, and there were no significant difference in splenic B cell proliferation in all treatment groups. As results of flow cytometric analysis of splenocyte, percentage total T cell, Th cell and Tc cell in PND21 exposed to penta-BDE was slightly increased, and percentage macrophage in dams and PND21 exposed to deca-BDE was decreased. The ELISA results of antibody production show no significant difference in all treatment groups relative to controls. CONCLUSION: These results imply that PBDEs given to the dam were transferred to the offspring during gestation and lactation, and PBDEs transferred from the dam affect immune system of offspring.

Assessment of dermal toxicity of nanosilica using cultured keratinocytes, a human skin equivalent model and an in vivo model.

Assessments of skin irritation potentials are important aspects of the development of nanotechnology. Nanosilica is currently being widely used for commercial purposes, but little literature is available on its skin toxicity and irritation potential. This study was designed to determine whether nanosilica has the potential to cause acute cutaneous toxicity, using cultured HaCaT keratinocytes (CHK), a human skin equivalent model (HSEM), and invivo model. Nanosilica was characterized by scanning electron microscopy. We evaluated the cytotoxic effects of nanosilica on CHKs and the HSEM. In addition, we also investigated whether two commercially available nanosilicas with different sizes (7 and 10-20 nm) have different effects. To confirm invitro results, we evaluated the irritation potentials of nanosilicas on rabbit skin. Nanosilicas reduced the cell viabilities of CHKs in a dose-dependent manner. However, the HSEM revealed no irritation at 500 microg/ml of nanosilica. Furthermore, this result concurred with Draize skin irritation test findings. The present study data indicate that nanosilica does not cause acute cutaneous irritation. Furthermore, this study shows that the HSEM used provides more useful screening data than the conventional cell culture model on the relative toxicities of NPs.