Kang Ji-houn;Kim Ju-hyang;Chung Chung-soo;Lee Chul-young;Yang Mhan-pyo
Journal of Veterinary Clinics
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v.21
no.4
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pp.336-342
/
2004
The immunoenhancing effect of CLA isomers (CLA mixture, 10t-12c CLA, 9c-11c CLA, 9c-11c CLA, and 9t-11t CLA) on phagocytic activity of porcine peripheral blood leukocytes was examined. The phagocytic activities of peripheral blood mononuclear cells (PBMC) and polymorphonuclear cells (PMN) were analyzed by a flow cytometry system. The direct treatments of CLA isomers have no effect on phagocytosis of PMN as well as PBMC composed of approximately 10% monocytes and 90% lymphocytes. However, the phagocytic activities of PMN and monocyterich fraction from PBMC were remarkably enhanced by culture supernatant from PBMC treated with CLA mixture, 10t-12c CLA and 9c-11t CLA but not 9c-11c CLA and 9t-11t CLA. The phagocytic activity of PBMC was not enhanced by culture supernatant from PBMC treated with all CLA isomers. These results indicated that CLA isomers such as CLA mixture, l0t -12c CLA and 9c-11t CLA have an enhancing effect on phagocytosis of PMN and monocytes, which may be mediated through active humoral substances produced by CLA-stimulated PBMC. This study suggested that CLA stimulates PBMC to elaborate soluble factor(s), which may be an important mechanism for the enhancement of phagocytosis in non-specific immunity.
This study was undertaken to clarify the effects of omega-3 fatty acid on endotoxin-induced acute lung injury. Rabbits were randomly assigned to one of four groups. Each group received intravenous infusion of saline only, saline and Escherichia coli endotoxin, omegaven infuison (0.5 mL/kg/hr) and endotoxin, lipoven (0.5 mL/kg/hr) and endotoxin respectively. Infusion of saline was started 0.5 hr before the infusion of saline or endotoxin, and omegaven and lipoven were started 2 hours after endotoxin infusion for 4 hours. The lungs of rabbits were ventilated with 40% oxygen. Mean blood pressure, heart rate, arterial oxygen tension (PaO2), and peripheral blood leukocyte were recorded. The wet/dry (W/D) weight ratio of lung and lung injury score were measured, and analysis of bronchoalveolar lavage fluid (BALF) was done. Endotoxin decreased PaO2, and peripheral blood leukocyte and platelet count. And it increased W/D ratio of lung, lung injury score and leukocyte count, percentage of PMN cells, concentration of IL-8 in BALF. Omegaven attenuated all these changes except for peripheral blood leukocyte counts. Omegaven attenuated endotoxin-induced acute lung injury in rabbits mainly by inhibiting neutrophil and IL-8 responses, which may play a central role in endotoxin-related lung injury.
This study examined the effect of pine needle distillate (Pinus densiflora Sieb. et Zucc) on the immune system and hematological parameters. C57BL/6 male mice weighing 20 ~21 g were divided into 3 groups and intraperitonially injected with either 200 $\mu$L of saline (control), 50% diluted (P50) or 100% pine needle distillate (P100) once a day for 24 days. At the end of the experiment, the mice were anesthetized by ether and peripheral blood was collected from the femoral artery and the spleen was excised. Spleen weight decreased significantly (p<0.001) in the pine needle groups compared to the control group. The blood was used for a complete blood count and flow cytometrical analysis after immunofluorescence staining. The pine needle distillate dose-dependently decreased the CD4$^{+}$/CD8 sup +/ ratio (p <0.05), and showed a tendency to increase the mean FSC (forward scatter) values of the CD8$^{+}$T cells, while decrease the values of the CD4$^{+}$T cells. There were no significant differences in WBC, RBC and platelet counts among the three groups, but hemoglobin and hemoglobin-related parameters and platelet volume increased and red blood cell volumes decreased with the administration of the pine needle distillate. These results suggest that the pine needle distillate may have immunosuppressive effects.
Lee, Dae Hyoung;Chung, Nak Gyun;Jeong, Dae Chul;Cho, Bin;Kim, Hack Ki
Clinical and Experimental Pediatrics
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v.51
no.12
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pp.1336-1341
/
2008
Purpose : This study aimed to determine the frequencies of $CD4^+CD25^+$ T cells in donor graft and peripheral blood $CD4^+CD25^+$ T cells in recipients after hematopoietic stem cell transplantation (HSCT) and their association with graft-versus-host disease (GVHD). Methods : Seventeen children who underwent HSCT were investigated. $CD4^+CD25^+$ T cells in samples from donor grafts and recipient peripheral blood were assessed by flow cytometry at 1 and 3 months after transplantation. Results : $CD4^+CD25^+$ T cell frequencies in the grafts showed no significant difference between patients with and without acute GVHD (0.90% vs. 1.06%, P=0.62). Absolute $CD4^+CD25^+$ T cell number in grafts were lower in patients with acute GVHD than in those without acute GVHD ($6.18{\times}10^5/kg$ vs. $25.85{\times}10^5/kg$, P=0.09). Patients without acute GVHD showed a significant decrease in peripheral blood $CD4^+CD25^+$ T cell percentage at 3 months compared to those at 1 month after HSCT (2.11% vs. 1.43%, P=0.028). However, in patients with acute GVHD, $CD4^+CD25^+$ T cell percentage at 3 months was not different from the corresponding percentage at 1 month after HSCT (2.47% vs. 2.30%, P=0.5). Conclusion : The effect of frequencies of $CD4^+CD25^+$ T cells in donor grafts on acute GVHD after HSCT could not be identified, and the majority of peripheral blood $CD4^+CD25^+$ T cells in patients who underwent HSCT may be activated T cells related to acute GVHD rather than regulatory T cells. Further studies with additional markers for regulatory T cells are needed to validate our results.
Hypertension caused by high-fat and high-salt diets is is a well-known significant risk factor for cardiovascular and cerebrovascular diseases. In this study, to confirm the relationship between hypertension and immune cells, angiotensin (Ang) II was administered to Dahl salt-sensitive (SS) rats and Dahl salt-resistant (SR) rats. Then the expression of immune cells and the proinflammatory cytokines were compared between the SS and SR rats. It was observed that after administration of Ang II (50ng/kg/min) for three weeks, blood pressure was increased in the SS rats, but there was no significant change in the SR rats. In addition, the expression of T helper (Th) cells and Th 17 cells in the spleen and the expression of Th cell Rorγt and regulatory T regulatory (Treg) cells in the peripheral blood mononuclear cells did not show a significant difference between the two experimental groups even after the administration of Ang II.IL-1β expression was significantly increased in the kidney tissue of the SS rats, while there was no significant difference in the IL-6 expression in all the experimental groups. The results of this study suggest that Ang II induces hypertension by stimulating IL-1β secretion from renal macrophage in SS rats.
Purpose : This study quantitatively evaluated the apoptosis In human peripheral blood lymphocytes using flow cytometry, and investigated the possibility of using this method, with a small amount of blood, and the time and dose dependence of radiation-induced apoptosls. Materials and Methods : Peripheral blood lymphocyes were isolated from the heparinized venous blood of 11 healthy volunteers, 8 men and 3 women, with each 10 ml of blood being divided Into IS samples. The blood lymphocytes were Irradiated using a linear accelerator at a dose rate of 2.4 Gy/min, to deliver doses of 0.5, 1, 2 and S Gy. The control samples, and Irradiated cells, were maintained in culture medium for 24, 48 and 72 hours fellowing the Irradiation. The number of apoptotic cells after the in vitro X-irradiation was measured by flow cytometry after Incubation periods of 24, 48 and 72 hours. We also observed the apoptotic cells using a DNA fragmentation assay and electron microscopy. Results : The rate oi spontaneous apoptosis increased in relation to the time interval following irradiation (1.761 ${\pm}$0.161, 3.563${\pm}$0.554, 11.098${\pm}$2.849, at 24, 48, and 72 hours). The apoptotli cells also increased In the samples irradiated with 0.5, 1, 2 and 5 Gy, In a radiation dose and time interval after Irradiation manner, with the apoptosls being too great at 72 hours after Irradiation. The dose-response curves were characterized by an Initial steep Increase In the number of apoptotic cells for Irradiation doses below 2 Gy, with a flattening of the curves as the dose approached towards 5 Gy. Conclusion :The flow cytometric assay technique yielded adequate data, and required less than 1 mL of blood. The time and dose dependence of the radiation-induced apoptosis, was also shown. It is suggested that the adequate time Interval required for the evaluation of apoptosis would be 24 to 48 hours after blood sampling.
Cha, Sun Hwa;Park, Chan Woo;Kim, Hae Suk;Cho, Dong Hee;Kim, Jin Young;Kang, Inn Soo;Koong, Mi Kyoung;Yang, Kwang Moon
Clinical and Experimental Reproductive Medicine
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v.32
no.2
/
pp.165-170
/
2005
Objective: The aim of present study was to evaluate the effectiveness of low-dose intravenous immunoglobulin (IVIg) therapy in women with recurrent spontaneous abortions (RSA) and elevated pre-conceptional peripheral blood CD56+Natural Killer (NK) cell percentage. Study Design: Retrospective case control study. Materials and Methods: Thirty three women with RSA and elevated pre-conceptional peripheral blood CD56+NK cell percentage who had received low-dose IVIg therapy (400 mg/kg per day, every 4 week, until 20 gestational weeks) were included in this study. Controls were nine women with RSA and elevated pre-conceptional peripheral blood CD56+ Natural Killer (NK) cell percentage who had not received IVIg therapy were included in this study. Medical records of study and control groups were retrospectively analyzed and we compared the successful pregnancy outcomes between two groups. Successful pregnancy outcome was defined as pregnancy ongoing beyond 25 gestational weeks. Results: Age, number of previous abortions, pre-conceptional CD56+NK cell percentage and type of RSA were not statistically different between two groups. Otherwise, twenty-five women who received IVIg therapy (25/33, 75.8%) but, only three women who had not received (3/9, 33.3%) had a successful pregnancy outcome and the rate difference between two groups was statistically significant. Conclusion: Based on our study, low-dose IVIg therapy have a effective role in treatment of RSA patients with elevated pre-conceptional peripheral blood CD56+ Natural Killer (NK) cell percentage, but more larger scaled prospective study is needed for available of conclusive evidence.
Plasma protein which has been known as one of nonspecific immunostimulators was added to feedstuff to examine its effect on the enhancement of cellular immune response in porcine immune system. A total of 40 piglets, 20 male and 20 female each, were fed for 30 days with or without plasma protein. The peripheral blood were collected and analyzed for the investigation of leukocyte subpopulations and their activities by using a panel of monoclonal antibodies specific to porcine leukocyte differentiation antigens and flow cytometry. The results obtained as follows. 1. Total weight gain, daily feed intake and feed conversion rate for 10 days were significantly improved to 56%, 20% and 22% in the piglets fed plasma protein, respectively. 2. A significant increase in N (null or non T/non B) cells was also noticed. Leukocyte proportion from piglets fed plasma protein was 20.2-24.7%, otherwise that from piglets fed without plasma protein was 12.3-13.4%, respectively. 3. A significant increase in the proportion of B cells and cells expressing poCD1 was not found in piglets fed plasma protein. 4. Reaction with monoclonal antibodies specific to adhesion molecules, poCD11a, poCD11b, poCD44 and poCD45A and poCD45B, has shown that leukocyte subpopulation from piglets fed plasma protein did not significantly higher than that from piglets fed without plasma protein. 5. Total proportion of granulocytes and monocytes was about 50% in both group and the proportion after treated with Hypaque/Ficoll was 2.7% and 5.8% in each group, respectively.
We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.
The chances of accidental exposure are augmented as the application of ionizing radiation increases in various fields. Such accidental exposures may occur at nuclear power plants, laboratories, and hospitals. Cytogenetic assays have been used for estimating radiation dose in the situation of the accidents. The micronucleus assay has several advantages over the other cytogenetic methods as it is simple and fast. The present study aimed at investigation of the micronuclei frequencies in cytokinesis-block cells in human blood lymphocytes after ${\gamma}$-irradiation and at establishment of a standard dose response relationship. The samples of peripheral blood were obtained from 6 different donors aged between 24 and 30 years old. The bloods were irradiated in vitro with 0-5 Gy. A linear quadratic dose-response equation was obtained by scoring the micronuclei in binucleated cells; $y=27.87x^2+46.13x+2.08$ ($r^2=0.99$). Irradiation caused a significant decrease in the nuclear division index. Necrotic and apoptotic cells increased in number after irradiation in a dose-dependent manner. In conclusion, the conventional cytokinesis-block micronucleus assay has proven to be the great technique in biological dosimetry. Dose-response calibration curve derived from CMBN assay could be used to estimate the exposure dose during a radiological emergency.
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