RESUMEN
Raphanus sativus (Cruciferaceae), commonly known as radish is widely available throughout the world. From antiquity it has been used in folk medicine as a natural drug against many toxicants. The present study was designed to evaluate the hepatoprotective activity of radish (Raphanus sativus) enzyme extract (REE) in vitro and in vivo test. The IC50 values of REE in human liver derived HepG2 cells was over 5,000 microg/ml in tested maximum concentration. The effect of REE to protect tacrine-induced cytotoxicity in HepG2 cells was evaluated by MTT assay. REE showed their hepatoprotective activities on tacrine-induced cytotoxicity and the EC50 value was 1,250 microg/ml. Silymarin, an antihepatotoxic agent used as a positive control exhibited 59.7% hepatoprotective activitiy at 100 microg/ml. Moreover, we tested the effect of REE on carbon tetrachloride (CCl4)-induced liver toxicity in rats. REE at dose of 50 and 100 mg/kg and silymarin at dose of 50 mg/kg were orally administered to CCl4-treated rats. The results showed that REE and silymarin significantly reduced the elevated levels of serum enzyme markers induced by CCl4. The biochemical data were supported by evaluation with liver histopathology. These findings suggest that REE, can significantly diminish hepatic damage by toxic agent such as tacrine or CCl4.
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Animales , Humanos , Ratas , Tetracloruro de Carbono , Células Hep G2 , Concentración 50 Inhibidora , Hígado , Medicina Tradicional , Raphanus , Silimarina , TacrinaRESUMEN
Plasma cholesterol is increased in normal aging in both rodents and humans. This is associated with reduced elimination of cholesterol and decreased receptor-mediated clearance of plasma low-density lipoprotein (LDL) cholesterol. The aims of this study were: (1) to determine age-related changes in plasma lipid profiles, and (2) to determine the effect of fenofibrate, an activator of peroxisome proliferator activated receptor alpha (PPAR alpha), on plasma lipid profiles in normal rats on a standard diet. Male Sprague-Dawley (SD) rats (n=15) were fed standard chow and water from 10 to 25 weeks of age. During that period, we measured daily food intake, body weight, fasting and random blood glucose levels, plasma total cholesterol (TC), triglycerides (TG), and free fatty acid (FFA) levels. At 20 weeks of age, all rats were randomly divided into two groups: a fenofibrate group (in which rats were gavaged with 300 mg/kg/day of fenofibrate) and a control group (gavaged with water). Fenofibrate treatment lasted 5 weeks. There were no significant changes in daily food intake, blood glucose, and plasma TG level with age. Body weight, plasma TC, and FFA levels were significantly increased with age. Fenofibrate significantly decreased plasma concentrations of TC and FFA, which had been increased with age. However, fenofibrate did not influence the plasma concentration of TG, which had not increased with age. These results suggest that fenofibrate might have a novel role in preventing age-related hypercholesterolemia in SD rats on a normal diet.
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Animales , Humanos , Masculino , Ratas , Envejecimiento , Glucemia , Peso Corporal , Colesterol , Dieta , Ingestión de Alimentos , Ayuno , Fenofibrato , Hipercolesterolemia , Lipoproteínas , Plasma , PPAR alfa , Ratas Sprague-Dawley , Roedores , Triglicéridos , AguaRESUMEN
The aim of this study was to determine the in vitro anti-inflammatory effect of hot water extract from Cordyceps militaris fruiting bodies (CMWE) on lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) release in RAW 264.7 cells. The treatment of macrophages with various concentrations of hot CMWE significantly reduced LPS-induced production as well as NO, TNF-alpha and IL-6 secretion in a concentration-dependent manner. These results suggest that CMWE have potent inhibitory effects on the production of these inflammatory mediators.
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Cordyceps , Frutas , Interleucina-6 , Macrófagos , Óxido Nítrico , Factor de Necrosis Tumoral alfa , AguaRESUMEN
In the peripheral nerves, injury-induced cytokines and growth factors perform critical functions in the activation of both the MEK/ERK and JAK/STAT3 pathways. In this study, we determined that nerve injury-induced ERK activation was temporally correlated with STAT3 phosphorylation at the serine 727 residue. In cultured Schwann cells, we noted that ERK activation is required for the serine phosphorylation of STAT3 by neuropoietic cytokine interleukin-6 (IL-6). Serine phosphorylated STAT3 by IL-6 was transported into Schwann cell nuclei, thereby indicating that ERK may regulate the transcriptional activity of STAT3 via the induction of serine phosphorylation of STAT3. Neuregulin-1 (NRG) also induced the serine phosphorylation of STAT3 in an ERK-dependent fashion. In contrast with the IL-6 response, serine phosphorylated STAT3 induced by NRG was not detected in the nucleus, thus indicating the non-nuclear function of serine phosphorylated STAT3 in response to NRG. Finally, we determined that the inhibition of ERK prevented injury-induced serine phosphorylation of STAT3 in an ex-vivo explants culture of the sciatic nerves. Collectively, the results of this study show that ERK may be an upstream kinase for the serine phosphorylation of STAT3 induced by multiple stimuli in Schwann cells after peripheral nerve injury.
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Núcleo Celular , Citocinas , Péptidos y Proteínas de Señalización Intercelular , Interleucina-6 , Neurregulina-1 , Traumatismos de los Nervios Periféricos , Nervios Periféricos , Fosforilación , Fosfotransferasas , Células de Schwann , Nervio Ciático , SerinaRESUMEN
The binding of interleukin-6 (IL-6) cytokine family ligands to the gp130 receptor complex activates the Janus kinase (JAK)/ signal transducer and activator of transcription 3 (STAT3) signal transduction pathway, where STAT3 plays an important role in cell survival and tumorigenesis. Constitutive activation of STAT3 has been frequently observed in many cancer tissues, and thus, blocking of the gp130 signaling pathway, at the JAK level, might be a useful therapeutic approach for the suppression of STAT3 activity, as anticancer therapy. AG490 is a tyrphostin tyrosine kinase inhibitor that has been extensively used for inhibiting JAK2 in vitro and in vivo. In this study, we demonstrate a novel mechanism associated with AG490 that inhibits the JAK/STAT3 pathway. AG490 induced downregulation of gp130, a common receptor for the IL-6 cytokine family compounds, but not JAK2 or STAT3, within three hours of exposure. The downregulation of gp130 was not caused by enhanced degradation of gp130 or by inhibition of mRNA transcription. It most likely occurred by translation inhibition of gp130 in association with phosphorylation of the eukaryotic initiation factor-2alpha. The inhibition of protein synthesis of gp130 by AG490 led to immediate loss of mature gp130 in cell membranes, due to its short half-life, thereby resulting in reduction in the STAT3 response to IL-6. Taken together, these results suggest that AG490 blocks the STAT3 activation pathway via a novel pathway.
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Humanos , Membrana Celular , Supervivencia Celular , Transformación Celular Neoplásica , Regulación hacia Abajo , Estrés del Retículo Endoplásmico , Semivida , Interleucina-6 , Janus Quinasa 2 , Ligandos , Fosforilación , Fosfotransferasas , Biosíntesis de Proteínas , Proteínas Tirosina Quinasas , ARN Mensajero , Transducción de Señal , Factor de Transcripción STAT3 , TirfostinosRESUMEN
Mesenchymal stem cells (MSC) are multipotent in nature and believed to facilitate the engraftment of hematopoietic stem cells (HSC) when transplanted simultaneously in animal studies and even in human trials. In this study, we transfected culture-expanded MSC with granulocyte macrophage-colony stimulating factor (GMCSF) and stem cell factor (SCF) cytokine genes and then cotransplanted with mononuclear cells (MNC) to further promote HSC engraftment. MNC were harvested from cord blood and seeded in long-term culture for ex vivo MSC expansion. A total of 1 x 10(7) MNC plus MSC/microliter were introduced to the tail vein of nonobese diabetic/severe combined immunodeficiency mice. After 6-8 weeks later, homing and engraftment of human cells were determined by flow cytometry and fluorescence in situ hybridization studies. The total nucleated cell count and the engraftment of CD45+/CD34+ cells and XX or XY positive human cells were significantly increased in cotransplanted mice and even higher with the cytokine gene-transfected MSC (GM-CSF>SCF, p<0.05) than in transplantation of MNC alone. These results suggest that MSC transfected with hematopoietic growth factor genes are capable of enhancing the hematopoietic engraftment. Delivering genes involved in homing and cell adhesions, CXCR4 or VLA, would further increase the efficiency of stem cell transplantation in the future.
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Ratones , Animales , Transfección/métodos , Factor de Células Madre/genética , Ratones SCID , Células Madre Mesenquimatosas/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Supervivencia de Injerto/inmunología , Mejoramiento Genético/métodosRESUMEN
PURPOSE: To investigate the degree and effect of cyclooxygenase (COX)-2 expression on the survival of patients with glioblastoma multiforme (GM). MATERIALS AND METHODS: Between 1997 and 2006, thirty consecutive GM patients treated with surgery and postoperative radiotherapy (dose range: 44~65.1 Gy, median dose: 61.2 Gy) were included in the study. Three patients were excluded that discontinued radiotherapy before receiving a dose of 40 Gy due to mental deterioration. The expression of the COX-2 protein in surgical specimens was examined by immunohistochemical analysis. Survival analysis and verification were performed with respect to sex, age, performance status, resection extent, radiotherapy dose, and degree of COX-2 expression using the Kaplan-Meier method and the log rank test. RESULTS: The median length of follow-up was 13.3 months (range: 6~83 months). Staining for COX-2 was positive in all patient samples. Staining for COX-2 that was positive for over 75% of the tumor cells was found in 24 patients. Staining for COX-2 that was positive in less than 25% of tumor cells was found in 3 patients (10.0%), staining for COX-2 that was positive in 25 to 50% of tumor cells was found in 1 patient (3.3%), staining for COX-2 that was positive in 50 to 75% of tumor cells was found in 2 patients (6.7%) and staining for COX-2 that was positive in 75 to 100% of tumor cells was found in 24 patients (80.0%). The median survival and two-year survival rate were 13.5 months and 17.5%, respectively. The survival rate was influenced significantly by the degree of resection (tumor removal by 50% or more) and radiotherapy dose (59 Gy or greater) (p0.05), and the two-year survival for these groups was 33.3 and 13.3%, respectively (p>0.05). CONCLUSION: The absence of a statistical correlation between the degree of COX-2 expression and survival in GM patients, despite the high rate of COX-2 positive tumor cells in the GM patient samples, requires further studies with a larger series to ascertain the prognostic value of the degree of COX-2 expression in GM patients.
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Humanos , Ciclooxigenasa 2 , Estudios de Seguimiento , Glioblastoma , Prostaglandina-Endoperóxido Sintasas , Radioterapia , Tasa de SupervivenciaRESUMEN
Type I diabetes (T1D) is an organ-specific autoimmune disease caused by the T cell-mediated destruction of the insulin-producing beta cells in the pancreatic islets. The onset of T1D is the consequence of a progressive destruction of islet beta cells mediated by an imbalance between effector CD4+ T helper (Th)1 and regulatory CD4+ Th2 cell function. Since interferon-alpha (IFN-alpha) has been known to modulate immune function and autoimmunity, we investigated whether administration of adenoviral-mediated IFN-alpha gene would inhibit the diabetic process in NOD mice. The development of diabetes was significantly inhibited by a single injection of adenoviral-mediated IFN-alpha gene before 8 weeks of age. Next, we examined the hypothesis that Th2-type cytokines are associated with host protection against autoimmune diabetes, whereas Th1-type cytokines are associated with pathogenesis of T1D. The expression of IFN-alpha induced increase of serum IL-4 and IL-6 (Th2 cytokines) levels and decrease of serum IL-12 and IFN-gamma (Th1 cytokines) levels. Therefore, overexpression of IFN-alpha by adenoviral-mediated delivery provides modulation of pathogenic progression and protection of NOD mice from T1D.
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Animales , Ratones , Enfermedades Autoinmunes , Autoinmunidad , Citocinas , Diabetes Mellitus Tipo 1 , Inmunomodulación , Interferón-alfa , Interleucina-12 , Interleucina-4 , Interleucina-6 , Islotes Pancreáticos , Ratones Endogámicos NOD , Células Th2RESUMEN
Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) has been reported to specifically kill malignant cells but to be relatively nontoxic to normal cells. One of disadvantages to previous in vivo protocols was the need for large quantities of TRAIL recombinant protein to suppress tumor growth. To evaluate the antitumor activity and therapeutic value of the TRAIL gene, we constructed adenoviral vectors expressing the human TRAIL gene (Ad.hTRAIL) and transferred them into malignant glioma cells in vitro and tumors in vivo, as an alternative to recombinant soluble TRAIL protein. The results show that TRAIL-sensitive glioma cells infected Ad.hTRAIL undergo apoptosis through the production and expression of TRAIL protein. The in vitro transfer elicited apoptosis, as demonstrated by the quantification of viable or apoptotic cells and by the analysis of cleavage of poly (ADP-ribose) polymerase. Furthermore, in vivo administration of Ad.hTRAIL at the site of tumor implantation suppressed the outgrowth of human glioma xenografts in SCID mice. These results further define Ad.hTRAIL as an anti-tumor therapeutic and demonstrate its potential use as an alternative approach to treatment for malignant glioma.
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Animales , Humanos , Ratones , Adenoviridae/genética , Apoptosis , Proteínas Reguladoras de la Apoptosis/genética , Línea Celular Tumoral , Expresión Génica , Terapia Genética/métodos , Glioma/patología , Glicoproteínas de Membrana/genética , Ratones SCID , Trasplante de Neoplasias , Trasplante Heterólogo , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
OBJECTIVE: Because of the limited penetration into the central nervous system after systemic administration of numerous therapeutic compounds, intratumoral chemotherapy for brain tumors has also been used. However, the efficacy of intratumoral drug administration is restricted by the poor diffusion of drug through tumor and brain interstitium. In order to enhance the diffusion of chemotherapeutic agent and increase the cytotoxicity with minimal dose, the authors report the results of convection-enhanced delivery(CED) of chemotherapeutic agent to the malignant brain tumor as a method of enhancing cerebral drug delivery. METHODS: Authors used "CADD-Micro(R) ambulatory infusion pump" from Deltec, which can be programmed for continuous infusion. Intratumoral injection of chemotherapeutic drug using the pump was applied to eight patients with glioma and one patient with lymphoma. Surgery was done and tumor was removed as much as possible. The tip of catheter was placed in the center of tumor cavity. Adriamycin (0.16~0.32mg) was put in the reservoir which was connected to the proximal catheter and fixed in the pump device. Twenty-four hours after surgery, Adriamycin was infused. RESULTS: There was no adverse reaction of CED technique. Compared with current delivery techniques, the improvement of survival rate has been observed(5 patients: alive, 3 patients: dead, 1 patient: lost(alive to 5 mo.)). CONCLUSION: CED can be useful method for distributing therapeutic molecules in the interstitial space of tumor and can be utilized for chemotherapeutic agents, immunotoxins, and gene etc..
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Humanos , Encéfalo , Neoplasias Encefálicas , Catéteres , Sistema Nervioso Central , Difusión , Doxorrubicina , Quimioterapia , Glioma , Inmunotoxinas , Linfoma , Tasa de SupervivenciaRESUMEN
PURPOSE: The relationship between environmental pH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. MATERIAL AND METHODS: Mammary adenocarcinoma cells of A/J mice (SCK cells) in exponential growth phase were irradiated with a 137Cs irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at 37degrees C for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. RESULTS: The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in G2/M phase rapidly increased to about 70% at 12 h after an exposure to 12Gy and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in G2/M increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about 45% at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as 30-35% of the cells were still in the G2/M phase 48 h after irradiation. The percentage of cells in G1 phase then increased as the G2/M arrest began to recede. The radiation-induced G2/M arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. CONCLUSION: Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced G2/M arrest is prolonged in an acidic environment indicating that the suppression of radiation- induced apoptosis and prolongation of radiation-induced G2/M arrest in an acidic environment are related.
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Animales , Ratones , Adenocarcinoma , Apoptosis , Ciclo Celular , Línea Celular , Electroforesis en Gel de Agar , Citometría de Flujo , Fase G1 , Mano , Concentración de Iones de HidrógenoRESUMEN
PURPOSE: The relationship between environmental pH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. MATERIAL AND METHODS: Mammary adenocarcinoma cells of A/J mice (SCK cells) in exponential growth phase were irradiated with a 137Cs irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at 37degrees C for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. RESULTS: The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in G2/M phase rapidly increased to about 70% at 12 h after an exposure to 12Gy and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in G2/M increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about 45% at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as 30-35% of the cells were still in the G2/M phase 48 h after irradiation. The percentage of cells in G1 phase then increased as the G2/M arrest began to recede. The radiation-induced G2/M arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. CONCLUSION: Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced G2/M arrest is prolonged in an acidic environment indicating that the suppression of radiation- induced apoptosis and prolongation of radiation-induced G2/M arrest in an acidic environment are related.
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Animales , Ratones , Adenocarcinoma , Apoptosis , Ciclo Celular , Línea Celular , Electroforesis en Gel de Agar , Citometría de Flujo , Fase G1 , Mano , Concentración de Iones de HidrógenoRESUMEN
PURPOSE: To obtain basic data for development of a glioblastoma-specific immunotoxin, the expression of variable cell surface receptors on a human glioblastoma xenograft model was evaluated, using NOD/SCID mice. MATERIALS AND METHODS: We developed a xenograft model in NOD/SCID mice implanted with a human glioblastoma cell line (U-87MG). Immunohistochemical studies were performed on implanted tumor nodules (n=8) using antibodies against CD71, EGFR, IGF-IRalpha, CXCR4 and IL-4Ralpha. RESULTS: Expression of IL-4Ralpha, in implanted tumornodules, was the highest of the cell surface receptors evaluated in this study. However, the endothelial cells in, and around, the tumor nodules also revealed immunopositivity against IL-4Ralpha. The immunoreactivity of IL-4Ralpha, and other surface receptors such as CD71, IGF-IRalpha and EGFR, was prominent in tumor nodules associated with tumor necrosis. CONCLUSION: IL-4Ralpha would be a possible target for the development of glioblastoma-specific immunotoxin, although there are limitations due to its endothelial expression.
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Animales , Humanos , Ratones , Anticuerpos , Línea Celular , Células Endoteliales , Glioblastoma , Xenoinjertos , Inmunotoxinas , Ratones SCID , Necrosis , Receptores de Superficie CelularRESUMEN
No abstract available.
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Humanos , Actinobacillus , Aggregatibacter actinomycetemcomitans , Apoptosis , Células JurkatRESUMEN
OBJECTIVE: Immunotoxin therapy is a novel approach for the treatment of tumor, and it has been successfully used in the central nervous system. The purpose of this study is to evaluate the cytotoxicity of OKT9 ScFv-Diphtheria toxin fusion immunotoxin on various human brain tumor cell lines. METHODS: Immunotoxin which was composed of OKT9 ScFv and Diphtheria toxin was made. Its cytotoxicity on glioblastoma cell lines(U87MG, U118MG) and medulloblastoma cell line(TE671) was tested and compared with anti-cancer chemotherapeutic agents. And we also examined the relationship between its cytotoxicity and transferrin receptor expression. RESULTS: It showed most cytotoxicity on U87MG cell line and nearly no effect on U118MG cell line, moderate cytotoxicity on TE671 cell line in sixteen hours exposure experiment. In continuous exposure experiment, it showed moderate cytotoxicity on U118MG cell line, but showed strong cytotoxicity on other cell lines comparable or higher than anti-cancer chemotherapeutic agents. The relationship between its cytotoxicity and transferrin receptor expression was tested using flow cytometry, but no direct relationship could be found. CONCLUSION: Collectively, the result shows the cytotoxic effects of OKT9 ScFv-Diphtheria toxin fusion immunotoxin against various human brain tumor cell lines in continuous exposure experiment. Therefore, we suggest that this immunotoxin could be developed as a potential immunotherapeutic agent in the treatment of various human brain tumor clinically.
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Humanos , Neoplasias Encefálicas , Encéfalo , Línea Celular , Sistema Nervioso Central , Toxina Diftérica , Citometría de Flujo , Glioblastoma , Inmunotoxinas , Meduloblastoma , Receptores de TransferrinaRESUMEN
We assessed the cytokine combinations that are best for ex vivo expansion of cord blood (CB) and the increment for cell numbers of nucleated cells, as well as stem cells expressing homing receptors, by an ex vivo expansion of cryopreserved and unselected CB. Frozen leukocyte concentrates (LC) from CB were thawed and cultured at a concentration of 1x10(5)/mL in media supplemented with a combination of SCF (20 ng/mL)+TPO (50 ng/mL)+FL (50 ng/mL)+/-IL-6 (20 ng/mL)+/-G-CSF (20 ng/mL). After culturing for 14 days, the expansion folds of cell numbers were as follows: TNC 22.3+/-7.8~26.3+/-4.9, CFU-GM 4.7+/-5.1~11.7+/-2.6, CD34+CD38- cell 214.0+/-251.9~464.1+/-566.1, CD34+CXCR4+ cell 4384.5+/-1664.7~7087.2+/-4669.3, CD34+VLA4+ cell 1444.3+/-1264.0~2074.9+/-1537.0, CD34+VLA5+ cell 86.2+/-50.9~ 113.2+/-57.1. These results revealed that the number of stem cells expressing homing receptors could be increased by an ex vivo expansion of cryopreserved and unselected CB using 3 cytokines (SCF, TPO, FL) only. Further in vivo studies regarding the engraftment after expansion of the nucleated cells, as well as the stem cells expressing homing receptors will be required.
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Humanos , ADP-Ribosil Ciclasa/metabolismo , Antígenos CD/metabolismo , Antígenos CD34/metabolismo , Criopreservación , Sangre Fetal/citología , Integrina alfa4beta1/metabolismo , Integrina alfa5beta1/metabolismo , Proteínas de la Membrana , Receptores CXCR4/metabolismo , Receptores Mensajeros de Linfocitos/metabolismo , Factor de Células Madre , Células Madre/citología , TrombopoyetinaRESUMEN
Homing-associated cell adhesion molecules (H-CAM) on the CD34+ cells play an important role for the engraftment process following hematopoietic stem cell transplantation (HSCT). However, it seems that not only CD34+ cells but also other nucleated cells (NCs) with H-CAM could be implicated in the engraftment process and the proliferation of hematopoietic stem cells. We investigated the differences of HCAM and cell cycle status on the NCs in cord blood (CB), bone marrow (BM), and mobilized peripheral blood (PB). The proportions of CXCR4+ cells within the NC populations were greater in CB than in PB or BM (p=0.0493), although the proportions of CXCR4+, CD44+, and CD49d+ cells within the CB CD34+ cell populations were same within BM or PB. A lower proportion of CD34+CD49d+ cells within the CD34+ cell populations was more noted in CB than in PB or BM (p=0.0085). There were no differences in cell cycle status between CB and BM or PB. Our results suggest that the migrating potential of CB would be enhanced with increased CXCR4 expression on the NCs, but the adhesion potential of CB CD34+ cells would be less than that of PB and BM. These findings may help explain why the lower cell dose is required and engraftment is delayed in cord blood stem cell transplantation.
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Humanos , Antígenos CD34/metabolismo , Receptores de Hialuranos/metabolismo , Células de la Médula Ósea/metabolismo , Moléculas de Adhesión Celular/metabolismo , Ciclo Celular/fisiología , Proliferación Celular , Separación Celular , Sangre Fetal/citología , Citometría de Flujo , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/metabolismo , Integrina alfa4/metabolismo , Receptores CXCR4/metabolismoRESUMEN
Actinobacillus actinomycetemcomitans, a gram-negative, capnophiTic bacterium, is associated with several human diseases including periodontal disease. Products of A. actinomycetemcomitans exert immunomodulatory effects on various lymphoid populations, some of which may be implicated in the pathogenesis of periodontitis. It has been recently suggested that some of periodontopathic bacterial products might possess superantigenic (SAg) activities. In order to examine SAg activity of A. actinomycetemcomitans, we tried to purify immunomodulating factor (IMF) which can induce proliferation of mouse splenocytes and human PBMC. IMF fraction was obtained from the culture supernatant of A. actinomycetemcomitans by alcohol precipitation, ultrafiltration, size exclusion chromatography, and dye ligand affinity chromatography which has been widely used for the puri5cation of known SAgs. SDS-PAGE analysis showed that the factor migrated to a molecular mass of 40 kDa. The concentration of IMF which elicited maximal proliferative response of mouse splenocytes was ranged 1-10 ug/ml of protein on day 3 in culture. Human PBMC gave a similar response profile to IMF, but their maximal response was obtained by lower concentraion of IMF on day 2 in culture. This activity of IMF was heat and proteinase K sensitive and was not blocked by co-incubation with polymyxin B, a ligand for the lipid A region of lipopolysaccharide. T cell-enriched fraction of mouse splenocytes obtained by nylon wool column lost the response to IMF. Even though mitomycin C-treated antigen presenting cells were added to T cell-enriched fraction, the response to IMF was feeble as compared to unfractionated cells. Splenocytes depleted of T cells by anti-Thy 1.2 and complement also did not respond to IMF. These findings demonstrated that T cells are responsible for a minor proportion of the observed proliferation induced by IMF and the help of these cells are essential to the most of the proliferating cells which may be B cells. This observation was confirmed by flow cytometric analysis of responding lymphocyte subpopulations. These results indicate that IMF of A. actinomycetemcomitans does not act in a manner consistent with known SAgs but is more relevant to the explanation of pathologic findings of periodontal lesions.