Recent studies have showed that thrombosis is closely related to leucocytes involved in immunity. Interfering with the binding of leukocyte integrin Mac-1 and platelet GPIbα can inhibit thrombosis without affecting physiological coagulation. Mac-1-GPIbα is proposed as a potential safety target for antithrombotic agents. Guanxinning tablet (GXNT) is an oral Chinese patent medicine used for the treatment of angina pectoris, which contains phenolic acid active ingredients, such as salvianolic acids, ferulic acid, chlorogenic acid, caffeic acid, rosmarinic acid, tanshinol, and protocatechualdehyde. Our previous studies demonstrated that GXN exhibited significant antithrombotic effects, and clinical studies suggested that it did not increase bleeding risk. In addition, GXN exerted a significantly regulatory effect on immune inflammation. In the current study, we intended to evaluate the effects of GXN on bleeding events and explore the safety antithrombotic mechanism of GXN based on leukocyte-platelet interaction. First, we established a gastric ulcer model induced by acetic acid in rats and found that GXN not only did not increase the degree of gastrointestinal bleeding when gastric ulcer occurred, but also had a certain promoting effect on the healing of gastric ulcer. Second, in vitroexperiments showed that after pretreatment with GXN and activation by phorbol 12-myristate-13-acetate (PMA), the adhesion and aggregation of leukocytes with human platelets were reduced. It was also found that GXN reduced the expression and activation of Mac-1 in leucocytes, and inhibited platelet activation due to leukocyte engagement via Mac-1. Overall, the results suggest that GXN may be a safe antithrombotic agent, and its low bleeding risk mechanism is probably related to inhibited leukocyte-platelet aggregation and its interaction target Mac-1-GPIbα.
Animals ; Fibrinolytic Agents ; Humans ; Integrins ; Leukocytes ; Macrophage-1 Antigen ; Rats ; Stomach Ulcer ; Tablets ; Thrombosis

BACKGROUNDLittle is known of the effects of hydrocortisone on cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and its counterreceptors (LFA-1, Mac-1) in acute pancreatitis (AP). We investigated the effects of prior treatment with hydrocortisone on the production of ICAM-1 and its counterreceptors (LFA-1 and Mac-1) in AP of rats to clarify the effect of hydrocortisone on induced acute pancreatitis.

METHODSAcute pancreatitis was induced by infusion of 5% chenodeoxycholic acid into the pancreatic duct, followed by ligation of pancreatic duct. Before induction of acute pancreatitis, rats were treated with hydrocortisone (n = 20) or 0.9% saline (n = 20). Blood and specimens from pancreas and lung were obtained from 5 rats from each treatment euthanized at 1 hour or 3 hours, 6 hours, 12 hours. Expression of ICAM-1 was assessed by immunohistochemistry and Western blot analysis of pancreas and lungs. The expression of LFA-1 and Mac-1 on neutrophils was detected by flow cytometer. The therapeutic effect of hydrocortisone was assessed from injuries to pancreas and lung.

RESULTSICAM-1 expression in the pancreas of hydrocortisone group was significantly less than in control group at 3 hours and 6 hours. In the lungs of hydrocortisone group, ICAM-1 expression was significantly less than in control group at 3 hours, 6 hours and 12 hours. The expression of LFA-1 and Mac-1 on neutrophils in blood increased significantly in control group over hydrocortisone group. Increased expression of ICAM-1, LFA-1 and Mac-1 preceded leukocyte infiltration. Compared to untreated animals with acute pancreatitis, rats pretreated with hydrocortisone had significantly reduced histological lung injury and output of ascitic fluid.

CONCLUSIONSPrior treatment with hydrocortisone before the induction of acute pancreatitis ameliorates pulmonary injury and the output of ascitic fluid and reduces the expression of ICAM-1 and its counterreceptors (LFA-1, Mac-1) in acute pancreatitis.

Acute Disease ; Amylases ; blood ; Animals ; Hydrocortisone ; pharmacology ; therapeutic use ; Intercellular Adhesion Molecule-1 ; analysis ; Lymphocyte Function-Associated Antigen-1 ; blood ; Macrophage-1 Antigen ; blood ; Pancreatitis ; blood ; drug therapy ; Rats ; Rats, Sprague-Dawley

The role of Mac-1 as a receptor for Bordetella bronchiseptica infection of alveolar macrophages (AMphi) was examined using 6 strains (2 ATCC and 4 pathogenic field isolates) to assess B. bronchiseptica binding, uptake and replication in primary porcine AMphi. All B. bronchiseptica strains were rapidly killed by porcine serum in a dose- and time-dependent manner. However, heat-inactivated porcine serum (HIS) did not demonstrate any bacterial-killing activity, suggesting that complement may have a direct killing activity. All field isolates were more resistant to direct complement-mediated B. bronchiseptica killing. The uptake of B. bronchiseptica into AMphi was inhibited approximately 50% by antiMac-1 monoclonal antibodies in the medium. However, B. bronchiseptica phagocytosed in the presence of serum or HIS was not altered by anti-Mac-1 antibodies although more bacteria were internalized by addition of serum or HIS. These data suggest that Mac-1 is a target for direct uptake of B. bronchiseptica via opsoninindependent binding. The phagocytosed B. bronchiseptica, either via direct or serum-mediated binding, were efficiently killed by AMphi within 10 hr postinfection. This demonstrates that Mac-1-mediated B. bronchiseptica uptake is a bacterial killing pathway not leading to productive infections in AMphi.
Animals ; Antibodies, Bacterial/blood/immunology ; Bordetella bronchiseptica/*immunology ; Macrophage-1 Antigen/*immunology ; Macrophages, Alveolar/*immunology ; Phagocytosis ; Protein Binding ; Swine/*immunology/*microbiology

OBJECTIVETo construct a novel immunogene therapeutic plasmid that expresses human interleukin-12 (IL-12), granulocyte-macrophage colony stimulating factor (GM-CSF) and B7.1 and observe its expression in vivo and in vitro.

METHODSHuman IL-12 gene fragment was cloned into the upper stream of IRES gene in the previously constructed plasmid pVAX-IRES-GM-CSF-B7.1, and the positive recombinant plasmid pVAX-IL-12-GB was transfected into 293T cells via Lipofectamine 2000. The expressions of IL-12 and GM-CSF-B7.1 mRNA and proteins in the transfected cells were assayed by RT-PCR and ELISA, and B7.1 expression was tested by fluorescence-activated cell sorting and immunofluorescence assay. The plasmid pVAX-IL-12-GB was delivered into mouse muscle by electroporation, and the expression of IL-12 in the muscle tissue was identified by immunohistochemistry.

RESULTSEnzyme digestion, PCR and sequence analysis all confirmed successful construction of the recombinant plasmid pVAX-IL-12-GB. IL-12, GM-CSF and B7.1 expressions were all detected in transfected 293T cells, and the expression of IL-12 was also detected in the transfected mouse muscular tissues.

CONCLUSIONA novel anti-tumor immunogene vaccine constructed can be expressed both in vivo and in vitro, which facilitates further studies of tumor immunogene therapy.

Animals ; B7-1 Antigen ; genetics ; immunology ; Cancer Vaccines ; genetics ; immunology ; Electroporation ; Genetic Therapy ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; immunology ; Humans ; Interleukin-12 ; genetics ; immunology ; Mice ; Plasmids ; Transfection

Platelet clearance has already been studied in physiological and pathological conditions and shown its occurrence mainly in the liver and the spleen. It is still not clear what mechanisms are responsible for recognition and removal of either aged or damaged platelets by the scavenging system. So study of the clearance mechanism will be useful to prolong the survival time of platelets in vivo. And it may be related to a new strategy to store platelets. This article focuses on the advances in studies of the clearance mechanism of transfused platelet concentrates, including roles of P-selectin, GPI balpha and its receptor Mac-1 in platelet clearance, and effect of endogenous metalloproteinase in platelet clearance.
Blood Platelets ; physiology ; Blood Preservation ; Cellular Senescence ; Humans ; Macrophage-1 Antigen ; physiology ; Metalloproteases ; physiology ; P-Selectin ; physiology ; Platelet Activation ; Platelet Glycoprotein GPIb-IX Complex ; physiology ; Platelet Transfusion

BACKGROUNDIn response to the inflammatory reaction, circulating leukocytes aggregate and adhere to the endothelial cells and eventually pervade into tissues, resulting in cell damage. This study was to detect the inflammatory reactions in mouse focal cerebral ischemia and their distinct characteristics in the ischemic basal ganglia and surrounding cortex.

METHODSMice were subjected to permanent occlusion of the left middle cerebral artery (MCAO) by introducing a suture for 2 to 120 hours. The expression of intercellular adhesion molecule 1 (ICAM-1) and Mac-1 was determined immunohistochemically. The myeloperoxidase (MPO) activity of the ischemic regions was measured.

RESULTSFour hours after MCAO, the number of ICAM-1 positive vessels in the ischemic basal ganglia increased (9.2 +/- 2.8 per mm(2)), peaked at 48 hours (29.6 +/- 4.8 per mm(2)), and decreased after 72 hours. In the ischemic cortex, the number increased rapidly 4 hours after MCAO (19.4 +/- 6.1 per mm(2)), peaked at 48 hours (44.4 +/- 16.8 per mm(2)), and declined after 72 hours. Mac-1 positive cells were seen in the ischemic basal ganglia (3.4 +/- 1.2 per mm(2)) 12 hours after MCAO, peaked after 48 hours (20.2 +/- 6.3 per mm(2)), and decreased after 72 hours. In the ischemic cortex, however, the number increased 4 hours after MCAO (4.3 +/- 1.7 per mm(2)), peaked after 48 hours (20.9 +/- 8.4 per mm(2)), and remained high at 120 hours. The MPO activity increased in the ischemic basal ganglia 12 hours after MCAO (0.111 +/- 0.023 U/g), peaked after 24 hours (0.194 +/- 0.059 U/g), and decreased after 72 hours. In the ischemic cortex, the MPO activity increased 12 hours after MCAO (0.110 +/- 0.032 U/g), peaked after 24 hours (0.210 +/- 0.067 U/g), and remained elevated at 120 hours.

CONCLUSIONSThe increased expression of ICAM-1 in the ischemic brain of mouse in the early phase of MCAO followed by the over-expression of Mac-1 and the increased MPO activity suggests that focal ischemia leads to early onset of inflammation. The inflammatory response is more persistent and intensive in the ischemic cortex than in the ischemic basal ganglia.

Animals ; Basal Ganglia ; blood supply ; Brain Chemistry ; Brain Ischemia ; metabolism ; pathology ; Cerebral Cortex ; blood supply ; Cerebrovascular Circulation ; Inflammation ; etiology ; Intercellular Adhesion Molecule-1 ; analysis ; Macrophage-1 Antigen ; analysis ; Male ; Mice ; Middle Cerebral Artery ; Peroxidase ; analysis

OBJECTIVETo investigate the role of intercellular adhesion molecule-1 (ICAM-1) in the accumulation of polymorphonuclear neutrophils (PMN) in the lungs at the early stage of burns.

METHODSMyeloperoxidase content in lung tissues and bronchoalveolar lavage fluid (BALF) were detected. ICAM-1 and its mRNA expression in lung tissues were determined by immunohistochemical method and in situ hybridization. CD11b/CD18 expression on the peripheral PMNs was measured by flow cytometry.

RESULTSThe levels of myeloperoxidase in lung tissues and BALF after burn injury were markedly higher than those of control. Expression of ICAM-1 and its mRNA in the lung tissues and CD11b/CD18 on peripheral PMNs surface was significantly increased at 2, 6, 12, 24 h after burns.

CONCLUSIONSPMNs accumulation in the lungs is related to increased ICAM-1 expression on pulmonary microvascular endothelial cells and CD11b/CD18 expression on PMN at the early stage of burn injury.

Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; Burns ; blood ; immunology ; Cell Adhesion ; Immunohistochemistry ; In Situ Hybridization ; Intercellular Adhesion Molecule-1 ; analysis ; Lung ; blood supply ; Macrophage-1 Antigen ; analysis ; Neutrophils ; immunology ; pathology ; Peroxidase ; analysis ; RNA, Messenger ; analysis ; Rats ; Time Factors

Prostaglandin E2(PGE2) has been implicated as an immunosuppressive agent and plasma levels of PGE2 are elevated in patients sustaining thermal injury. We examined the effect of 10(-7) M prostaglandin E2(PGE2) on human polymorphonuclear leukocytes (PMN) to determine whether it directly inhibits stimulated responses of these cells. At this concentration, PGE2 alone was incapable of stimulating PMN intracellular hydrogen peroxide production (indirectly assayed by fluorescence of 2',7'ichlorofluorescin) or expression of the PMN CD11b/CD16 surface glycoproteins. PMN incubated in the presence of the soluble stimul phorbol myristate acetate(PMA, 100 ng/ml) or recombinant human C5a(rHC5a, 10(-8) M) generated significant amounts of hydrogen peroxide, increased their CD11b expression and decreased their CD16 expression. Pre-incubation of cells with PGE2 caused significant inhibition of all the observed changes stimulated by rHC5a. In contrast, events stimulated by PMA were not affected by preincubation of cells with PGE2. We conclude that PGE2, in concentrations identical to those found in the plasma of patients with burn injuries, is capable of selectively inhibiting some stimulated events and phenotypic expression of PMN in vitro study.
Dinoprostone/*pharmacology ; Dose-Response Relationship, Drug ; Human ; Hydrogen Peroxide/metabolism ; Immunosuppressive Agents/*pharmacology ; Macrophage-1 Antigen/biosynthesis ; Neutrophils/*drug effects/immunology ; Receptors, IgG/biosynthesis ; Support, Non-U.S. Gov't ; Temperature ; Tetradecanoylphorbol Acetate/pharmacology ; Time Factors

PURPOSE: Dendritic cells (DCs) are considered the most professional antigen-presenting cells (APCs) because of their unique role in initiating immunity against threatening antigens. Recently, hypertonicity has been suggested to be involved in the activation and development of immune cells such as T cells. And tonicity enhancer binding protein (TonEBP) has been thought to play a pivotal role in this process. Here, we studied the maturation status of DCs and expression of TonEBP in DCs exposed to hypertonic condition. METHODS: Murine bone marrow-derived DCs were generated in the presence of GM-CSF for 6 days, and then exposed to hypertonic media. We evaluated the functional capacities and maturation of DCs using flow cytometry, mixed lymphocyte reaction, and cytokine analysis. Also we investigated the expression of TonEBP in DCs cultured in variable hypertonic media. RESULTS: Mild hypertonicity made CD11c+ DCs to have up-regulation of CD40, 80, and 86. DCs exposed to 320 mOsm/kg media stimulated allogeneic T cell proliferation most effectively compared to DCs exposed to other tonic conditions. However, DCs exposed to 400 mOsm/kg media showed similar stimulatory capacities to isotonic control. Consistent with the phenotype changes, IL-1, 6, and TNF-alpha secretion increased in CD11c+ DCs exposed to mild hypertonic condition. Though we confirmed that TonEBP was expressed in CD11c+ DCs, the amount of upregulation was not dependent on the degree of hypertonicity. CONCLUSION: Our results suggest that hypertonicity enhances the maturation and activation of DCs.
Antigen-Presenting Cells ; Carrier Proteins ; Cell Proliferation ; Dendritic Cells ; Flow Cytometry ; Granulocyte-Macrophage Colony-Stimulating Factor ; Interleukin-1 ; Lymphocyte Culture Test, Mixed ; Osmolar Concentration ; Phenotype ; T-Lymphocytes ; Tumor Necrosis Factor-alpha ; Up-Regulation

This study was aimed to evaluate the in vivo antitumor effect of genetically modified myeloma cell vaccine on human myeloma xenografts implanted into nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Human immune system was established in NOD/SCID mice by intraperitoneal injection of human peripheral blood lymphocytes (PBLs). After being inoculated subcutaneously with irradiated myeloma cell line sko-007, adenovirally transferred with GFP or p53, granulocyte-macrophage colony-stimulating factor (GM-CSF) and B7-1 genes, huPBL-NOD/SCID mice were challenged by subcutaneous injection of non-transferred sko-007 cells. The results indicated that Ad-p53/GM-CSF/B7-1-infected sko-007 cell vaccination significantly reduced local tumor growth compared with controls. Histopathological and immunohistochemical analysis showed that tumor tissues increasingly displayed diffuse necrosis, mainly caused by apoptosis, accompanied with significant fibroplasias and blood vessel hyperplasia, and human T cells infiltrated into the tumor tissues. It is concluded that transgenic p53, GM-CSF and B7-1 expression produces an immune response against myeloma cells and may be of therapeutic value for multiple myeloma in human being.
Adenoviridae ; genetics ; Animals ; B7-1 Antigen ; genetics ; immunology ; Cancer Vaccines ; immunology ; Genes, p53 ; immunology ; Genetic Vectors ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; immunology ; Immunotherapy ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Multiple Myeloma ; immunology ; Neoplasm Transplantation