Therapeutic efficacy of human embryonic stem cell-derived endothelial cells in humanized mouse models harboring a human immune system.

OBJECTIVE: Allogeneic transplantation of human embryonic stem cell (hESC) derivatives has the potential to elicit the patient's immune response and lead to graft rejection. Although hESCs and their derivatives have been shown to have advantageous immune properties in vitro, such observations could not be determined experimentally in vivo because of ethical and technical constraints. However, the generation of humanized mice (hu-mice) harboring a human immune system has provided a tool to perform in vivo immunologic studies of human cells and tissues. Using this model, we sought to examine the therapeutic potential of hESC-derived endothelial cells, human embryonic fibroblasts, and cord blood-derived endothelial progenitor cells in a human immune system environment. APPROACH AND RESULTS: All cell types transplanted in hu-mice showed significantly reduced cell survival during the first 14 days post-transplantation compared with that observed in immunodeficient mice. During this period, no observable therapeutic effects were detected in the hindlimb ischemic mouse models. After this point, the cells demonstrated improved survival and contributed to a long-term improvement in blood perfusion. All cell types showed reduced therapeutic efficacy in hu-mice compared with NOD scid IL2 receptor gamma chain knockout mice. Interestingly, the eventual improvement in blood flow caused by the hESC-derived endothelial cells in hu-mice was not much lower than that observed in NOD scid IL2 receptor gamma chain knockout mice. CONCLUSIONS: These findings suggest that hESC derivatives may be considered a good source for cell therapy and that hu-mice could be used as a preclinical in vivo animal model for the evaluation of therapeutic efficacy to predict the outcomes of human clinical trials.

A therapeutic strategy for metastatic malignant fibrous histiocytoma through mesenchymal stromal cell-mediated TRAIL production.

OBJECTIVE: To overcome the therapeutic limitations of malignant fibrous histiocytoma (MFH), we evaluated human adipose tissue-derived mesenchymal stromal cells (MSCs) that secrete tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on metastatic MFH. BACKGROUND: MFH is a highly malignant and metastatic type of sarcoma but surgical removal is the only effective method for treating MFH. MSCs are easily transduced to express a high level of transgene and can migrate toward cancer. For this reason, MSCs are a promising candidate for metastatic MFH therapies. METHODS: In vitro sustainability of MSC-TRAIL against MFH-ino was analyzed by apoptosis assay. For preclinical study, anti-MFH effects of MSC-TRAILs were validated in murine models for local tumorigenesis and metastasis. Furthermore, a time-interval metastasis model of MFH was applied to confirm antimetastatic ability of MSC-TRAIL for preestablished metastatic MFH. RESULTS: We found that MFH-ino is highly susceptible to recombinant TRAIL and MSC-TRAIL, which selectively induce apoptosis via caspase-8 activation in vitro. Moreover, not only MFH-ino but xenograft explants were also significantly inhibited by MSC-TRAIL in local tumorigenesis. In particular, the metastatic ability of MFH-ino was considerably reduced by MSC-TRAIL in metastasis murine model, particularly for preestablished metastatic MFH. CONCLUSIONS: These results suggest that MSC-TRAIL is sufficiently effective in inhibiting MFH-ino metastasis and the application using MSC-TRAIL could be extended to other sarcomas and recurrent metastatic cancers for cell-mediated cancer therapy.

Enhancement of the immunosuppressive effect of human adipose tissue-derived mesenchymal stromal cells through HLA-G1 expression.

BACKGROUND AIMS: Mesenchymal stromal cells (MSC) from several tissues have immunomodulatory properties that involve various immunosuppressive molecules. An example is human leukocyte antigen (HLA)-G, a non-classical major histocompatibility complex (MHC) class I molecule that induces tolerance via interactions with inhibitory receptors present on major immune effector cells. Recently, the molecular mechanisms that regulate MSC-mediated immunosuppression have come under investigation. Our goal was to determine whether HLA-G plays a crucial role in immunosuppression and whether human adipose tissure (hAT) MSC can be used as a tool for biologic immunosuppression with HLA-G in transplantation. METHODS: MSC were characterized by fluorescence-activated cell sorting (FACS) analysis, reverse transcriptase (RT)-polymerase chain reaction (PCR) and staining for differentiation. The immunogenicity and immunomodulatory effects of MSC were monitored by peripheral blood mononuclear cell (PBMC) proliferation assay with or without phytohemagglutinin (PHA) stimulation. Stable expression of HLA-G1 in MSC was done using a lentiviral system. Results. MSC from different tissues had similar morphology, immunophenotypic characters and differentiation potential. We also found that the immunosuppressive effect of MSC was monitored along with their endogenous HLA-G mRNA and protein levels. Stable expression of HLA-G1 appeared to enhance the immunosuppressive effect of hAT MSC, and the function of HLA-G1 was significantly decreased by HLA-G antagonistic antibody in PBMC proliferation assays. CONCLUSIONS: Although the HLA-G molecule is not the sole factor for MSC-mediated immunosuppression, our data provide evidence that HLA-G plays an important role in immunosuppression and that hAT MSC can be used as a tool for biologic immunosuppression during transplantation procedures.

Increased Prevalence of Thalassemia in Young People in Korea: Impact of Increasing Immigration.

BACKGROUND: Thalassemia is highly prevalent in Southeast Asia but is rare in Korea; however, Southeast Asian immigrant population is recently rising in Korea. We investigated the prevalence of thalassemia in Korea in the context of increasing immigration. METHODS: This prospective, observational, multicenter study was conducted between September 2015 and August 2017. A total of 669 subjects <30 years living in Korea were grouped into the multiethnic (N=314) and Korean (N=355) groups. Hb electrophoresis and complete blood count (CBC) were performed. If low mean corpuscular volume with high red blood cell distribution width coefficient of variation or a high fetal Hb (HbF) or Hb alpha 2 (HbA2) level was observed, genetic testing of the α- and ß-globin genes was performed. In addition, the number of potential thalassemia carriers in Korea was estimated by multiplying the prevalence of thalassemia in a specific ethnicity by the number of immigrants of that ethnicity. RESULTS: Twenty-six multiethnic and 10 Korean subjects showed abnormal results for Hb electrophoresis and CBC. Eighteen multiethnic subjects and four Korean subjects were tested for α-globin and ß-globin gene mutations. Within the multiethnic group, five subjects (1.5%) were α-thalassemia carriers, and six (1.9%) were ß-thalassemia minor. The SEA deletion in HBA1 and HBA2, and c. 126_129delCTTT (p.Phe42Leufs*19) mutation of HBB were the dominant inherited mutations. CONCLUSIONS: The prevalence of thalassemia in young people in Korea is increasing due to the increasing number of Southeast Asian immigrants.

Frequency of Red Blood Cell Antigens According to Parent Ethnicity in Korea Using Molecular Typing.

Frequencies of red blood cell (RBC) blood group antigens differ by ethnicity. Since the number of immigrants is increasing in Korea, RBC antigens should be assessed in children/youths with parents of different ethnicities to ensure safe transfusions. We investigated the frequency of RBC antigens, except for ABO and RhD, in 382 children and youths with parents having Korean and non-Korean ethnicities. Subjects were divided into those with ethnically Korean parents (Korean group; N=252) and those with at least one parent of non-Korean ethnicity (non-Korean group; N=130). The 37 RBC antigens were genotyped using the ID CORE XT system (Progenika Biopharma-Grifols, Bizkaia, Spain). The frequencies of the Rh (E, C, e, hr(S), and hr(B)), Duffy (Fy(a)), MNS (Mi(a)), and Cartwright (Yt(b)) antigens differed significantly between the two groups. Eight and 11 subjects in the Korean and non-Korean groups, respectively, exhibited negative expression of high-frequency antigens, whereas 14 subjects in the non-Korean group showed positive expression of low-frequency antigens. The frequency of RBC antigens has altered alongside demographic changes in Korea and might lead to changes in distribution of RBC antibodies that cause acute or delayed hemolytic transfusion reaction.

Fatal systemic infection with multifocal liver and lung nodules caused by Brucella abortus.

We experienced a fatal case caused by Brucella abortus with multifocal necrosis confirmed by culture and polymerase chain reaction. Our case highlights that the clinician should be aware of the potential for fatality when a patient with brucellosis shows dissemination of abscess or nodules with no calcification in the liver, lung, pleura, and spine.

Performance review of the National Blood Safety Improvement Project in Korea (2004-2009).

BACKGROUND: In 2004, the Korean government and blood transfusion community deliberated on the issue of a national blood system reform and agreed to implement a 5-year project (2004-2009) to further improve safety measures. Our study delineates the basis of the current national blood program and analyzes the performance of this 5-year project initiated by the Korean government. METHODS: A performance review of the 5-year project was conducted from May 2009 to February 2010 using various approaches. Numerous data and documentation were collected from the Korean Red Cross and the Korean Centers for Disease Control and Prevention and reviewed by experts. Approximately 20 interviews with representatives of stakeholder groups were conducted to gather information, opinions, and perceptions. We conducted a nationwide field survey on a total of 144 blood donor centers. RESULTS: Among the 5 major categories of the 5-year project, blood donor recruitment, laboratory testing, and product manufacturing were improved in terms of quality performance. Specifically, government's financial support ensured that the infrastructure of blood donor centers and blood laboratory centers improved. The pivotal role of the government contributed to improvements in the national blood program and enhanced national surveillance for blood safety. CONCLUSION: Korea has made a tremendous effort with positive outcomes to provide safety measures for blood products for transfusion in its citizens. In all areas of blood management, from blood donations to transfusions, continuous developments in monitoring safety standards and practices are paramount.

Epidemiological characteristics of serologically confirmed q Fever cases in South Korea, 2006-2011.

OBJECTIVES: Q fever has been reported worldwide; however, there was almost no official report of Q fever in Korea. In this study, we describe the current status of human Q fever occurrence in Korea. METHODS: Demographic data of Q fever patients were collected from the National Notifiable Diseases Surveillance System from 2006 to 2011. Case investigation reports from regional public health departments were used for additional information, like risk factors and clinical manifestation, of the patients since 2008. RESULTS: There were 65 serologically confirmed cases during the study period. The annual notification rate of Q fever was 0.22 cases per million persons. The majority of cases were men (87.7%), adults (98.5%), and urban inhabitants (67.7%). Relevant exposures to risk factors were identified in 45.7% of patients. The most common symptoms of acute Q fever were fever (89.3%), myalgia (67.9%) and asthenia (53.6%). Two cases with endocarditis were identified in chronic Q fever. CONCLUSION: This study suggests that Q fever has a low endemicity in Korea. However, management and research at national level is required for prevention of a future epidemic.

Anesthetic management in patients suspected of Creutzfeldt-Jakob disease -A case report-.

Creutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disorder in which accumulation of the pathogenic prion protein induces neuronal damage and results in distinct pathologic features. This abnormal prion is an infectious protein and resistant to methods of sterilization currently being used. Therefore, management of definite, or suspected CJD patients requires additional precautions. We report our experience of a patient who had undergone brain biopsy for suspected of CJD. The patient was confirmed to have sporadic CJD.

Significance of CD133 as a cancer stem cell markers focusing on the tumorigenicity of pancreatic cancer cell lines.

PURPOSE: The cancer stem cell hypothesis states that the capacity of a cancer to grow and propagate is dependent on a small subset of cells. To determine the significances of the cancer stem cell markers CD133, CD44, and CD24 using a comparative analysis with a focus on tumorigenicity. METHODS: Four pancreatic cancer cell lines, Capan-1, Mia-PACA-2, Panc-1, and SNU-410 were analyzed for the expressions of CD133, CD44, and CD24 by flow cytometry. The tumorigenicity was compared using tumor volumes and numbers of tumors formed/numbers of injection in nonobese diabetic severe combined deficiency mice. Fluorescence-activated cell sorting (FACS) analysis was used to confirm that xenograft explants originated from human pancreatic cancer cells. RESULTS: CD133 was positive in only Capan-1, CD44 positive in all, CD24 partially positive in Panc-1. After injecting 2 × 10(6) cells, all mice administered Capan-1 or Mia-Paca-2 developed tumors, 3 of 5 administered Panc-1 developed tumors, but no mouse administered SNU-410 developed any tumors. The volumes of Capan-1 tumors were seven times larger than those of Mia-Paca-2 tumors. When 2 × 10(5) or 2 × 10(4) of Capan-1 or Mia-Paca-2 was injected, tumors developed in all Capan-1 treated mice, but not in Mia-Paca-2 treated mice. Furthermore, xenograft explants of Capan-1 expressed CD133+CD44+ and Capan-1 injected mice developed lung metastasis. FACS analysis showed that xenograft explants originated from human pancreatic cancer cell lines. CONCLUSION: CD133 positive cells have higher tumorigenic and metastatic potential than CD44 and CD24 positive cells, which suggests that CD133 might be a meaningful cell surface marker of pancreatic cancer stem cells.

The effect of nitroglycerin on hemodynamic changes during laparoscopic low anterior resection.

BACKGROUND: More laparoscopic low anterior resections (LAR) are being performed in recent years. There has been controversy around the hemodynamic changes affected by the Trendelenburg position and pneumoperitoneum during LAR. The goal of this study was to analyze the effect of nitroglycerin (NTG) on hemodynamic changes during LAR. METHODS: Forty ASA physical status I-II patients undergoing LAR were randomized into two groups: the NTG infused group (N group, n = 20) and the control group (C group, n = 20). Anesthesia was maintained with sevoflurane at 1-3 vol%, air/oxygen (50%/50%) and continuous infusion with remifentanil. The N group patients were given 0.5 µg/kg/min of NTG during anesthesia. Mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), cardiac index (CI), stroke volume (SV) and systemic vascular resistance (SVR) were assessed 10 min after induction (T1), 5 min after pneumoperitoneum in the supine position (T2), 10 min after pneumoperitoneum in the Trendelenburg position (T3), 30 min after pneumoperitoneum in the Trendelenburg position (T4), 1 hr after pneumoperitoneum in the Trendelenburg position (T5) in addition to 5 (T6), 10 (T7) and 30 min (T8) after removal of the pneumoperitoneum in the supine position. RESULTS: The increases of MAP were milder in the N group (22.6-7.3%) than the C group (32.3-17.7%) during pneumoperitoneum and while in the Trendelenburg position. The significant decreases of HR were maintained in the C group, but the changes in HR were not significant in N group during the operation. The increases in CVP were less in N group than C group. The increases of SVR were milder in N group (19.4-1.4%) than C group (41.7-16.6%) during pneumoperitoneum in the Trendelenburg position. CONCLUSIONS: Intraoperative NTG infusions were effective to some degree in reducing the hemodynamic changes during pneumoperitoneum with Trendelenburg positioning for LAR.

Registration of human embryonic stem cell lines: Korea, 2010.

In an effort to increase the credibility of human embryonic stem cell (hESC) lines established in Korea, obligatory registration was introduced by the Bioethics and Safety Act 2008, effective as of January 1, 2010. The DNA fingerprint, chromosome stability, expression of pluripotency markers, and contamination of mycoplasma of the submitted lines were analyzed by Korea Centers for Disease Control and Prevention (KCDC). The characterization data and ethical aspects, such as informed consent for donation of surplus embryos, were reviewed by a 10-member advisory review committee for stem cell registry. A total of 55 domestic hESC lines were submitted for registration in 2010; among them 51 were registered. Among these submitted lines, 26 were additionally characterized by KCDC, while 25 lines previously characterized by the Ministry of Education, Science and Technology were not additionally analyzed by KCDC. Registration completed an oversight system for embryo research by registering the products of licensed embryo research projects, making embryo research more transparent in Korea. Information about hESC lines is available at the website of the Korea Stem Cell Registry (kscr.nih.go.kr).

A sporadic outbreak of human brucellosis in Korea.

Eleven cases of human brucellosis occurred among livestock workers and a veterinarian who lived and worked in a rural area around Jeongeup City, Jeollabuk-Do, Korea from February 2003 to August 2003. Eight of the patients had taken care of Korean native cattle that were infected with bovine brucellosis and had already been slaughtered. Two of the patients had taken care of dairy cattle, and one case was a veterinarian who acquired the disease through an accidental contact with infected cattle while assisting in calf delivery. Eleven cases were identified by serologic work ups and four cases were identified via positive blood cultures. This study shows that the Republic of Korea is no longer free of human brucellosis, Brucella abortus biotype 1. We reviewed the patients' characteristics and serologic data during the one-year follow up period, and we also discuss on the efficacy and side effects of the rifampin and doxycyline regimen used for the treatment of human brucellosis.