Prostaglandin-endoperoxide synthase (cyclooxygenase, COX) catalyzes the first committed step of the biosynthesis of prostaglandins and thromboxane as potent biological mediators. Recently, a new isozyme of the COX (COX-2) was found whose expression is inducible by cytokines and growth factors. The expression of this inducible COX-2 is linked to inflammatory cell types and tissues, and is now believed to be a target enzyme for the anti-inflammatory activity of the NSAIDs.
To investigate the contribution of COX-2 in inflammatory process it is important to elucidate the regulatory mechanism of COX-2 gene expression. We have shown that the 5'-flanking region of human COX-2 gene contained a canonical TATA box and various transcriptional regulatory elements, and that the gene possesed a long 3'-flanking region containing many AUUUA motifs which have been shown to confer enhanced mRNA degradation.
Here, we review recent progress in the studies of the regulation of COX-2 gene expression.

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Gc globulin (Vitamin D₃ binding protein) modified by β-galactosidase of lysophosphatidylcholine-activated B cells and sialidase of T cells has been reported to enhance Fcγ receptor-mediated phagocytosis by murine peritoneal macrophages. In order to clarify the mechanism of enzymatically modified Gc globulin (mGc) -induced enhancement of Fc receptor mediated phagocytosis, we investigated the Fc receptor expression by rosette formation and flow cytometry. mGc enhanced Fc receptor-mediated phagocytosis and rosette formation dose dependently. Modified Gc also enhanced Fcγ receptor-mediated rosette formation in both the trypsintreated and cycloheximide-treated macrophages. Flow cytometric analysis revealed that mGc augmented the cell surface expression of FcγR I and FcγR II in macrophages. Modified Gc-induced enhancement of the Fc receptor-mediated phagocytosis and rosette formation was specifically inhibited by galactose and Nacetylgalactosamine.
These data suggest that mGc enhances Fcγ receptor-mediated phagocytosis in murine peritoneal macrophages by inducing translocation of FcγR I and FcγR II from intracellular storage compartments to the cell surface, and that Gal/GaINAc specific lectin of the macrophage surface membrane may be responsible for the mGc-induced activation.

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Synovial fibroblasts from patients with rheumatoid arthritis (RA) was tested for the proliferation and the production of IL-6. Synovial tissue was obtained from two or more joints of each patient for culture at radical multiple synovectomy (RaMS) .
The proliferation, determined by ³H-thimidine incorporation and by MTT assay, varies among patients and among joints. Although IL-6 was detected in culture supernatants, IL-6 levels did not correlate with the proliferation of synovial fibroblasts. The proliferation and IL-6 production did not correlate with RA activity nor laboratory findings (erythrocyte sedimentaion ratio, CRP) .
The proliferation of those cells from joints of upper extremities was higher than those from lower extremities. We speculate that the mechanism of cell proliferation is different from the mechanism of IL-6 production in Synovial fibroblasts.

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It is well known that persistent purulent nasal discharge with numerous neutrophils occurs in patients with chronic sinusitis (CS) . In recent years, IL-8 has been reported to be one of the major mediators which induce neutrophil activation and chemotaxis. The present study was performed in an attempt to investigate the role of IL-8 in neutrophil chemotaxis in CS. Immunohistochemical examinations revealed that IL-8 was expressed in polymorphonuclear cells in the nasal discharge and in epithelial and nasal gland cells of the ethmoidal mucosa. IL-8 concentration in the nasal discharge of CS determined by enzyme immunoassay was 28.3±7.3 nM (mean±SEM, n=10), which was significantly higher than that of nasal allergy. These results suggest that chemotactic factors in paranasal sinus effusion including IL-8 derived from epithelial cells and nasal gland cells attract neutrophils from the mucosa, and the neutrophils in the effusion secrete IL-8, which causes further neutrophil accumulation in the paranasal sinus effusion in CS.

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Objectives : In order to get an activating mechanism of cathepsin D, we immunohistochemically examined the production and transportation of H⁺ which activates an acid protease in pericellular region.
Materials and methods : Synovial tissues used in this study were obtained at total knee replacement. They were fixed in 4% paraformaldehyde for 2-3 hours, embedded in paraffin. 3μm thickened sections were examined by immunohistochemical method. Antibodies used in this study were anti-cathepsin D (Cat-D), carbonic anhydraseII (CAII), vacuolar type ATPase (V-ATPase) and CD68 (macrophage) antibodies. Serial sections were prepared for Cat-D, CAII and V-ATPase for elucidating Cat-D activation mechanism by H⁺ which is produced by CAII and is transported by V-ATPase. Furthermore, for identify the Cat-D positive cells in synovial tissues in which there are many kinds of cells, we used Immunohistochemical method.
Results : Osteoclasts and monocytes in granulation tissues around bony destruction (pannus), and chondrocytes neighboring to inflammatory region, and macrophages in synovial tissues intensively expressed Cat-D. The osteoclasts and chondrocytes intensively demonstrated CAII and V-ATPase, which indicated the Cat-D activation in pericellular region, however macrophages in synovial tissues did not always expressed CAII and V-ATPase intensively. Furthermore, immunoelectron microscopic study revealed that the macrophages with Cat-D had plenty of phagocytotic vacuoles, and these vacuoles fused with lysosomes containing Cat-D. These findings suggested that the Cat-D in macrophage of synovial tissues was utilized for digestive function of phagocytotic substance rather than deteriorating extracellular matrix.
Conclusion : It was histochemically revealed that cathepsin D in osteoclasts and chondrocyte participates in deteriorating the matrix, while in synovial tissue, this enzyme may play a role in digestion of intracytoplasmic substances.

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We evaluated the inhibitory effect of pretreatment of a mouse antiendotoxin monoclonal antibody (E5) on hypotension and oxygen radical production in the intact pulmonary microcirculation, using our original method which allows us to visualize the hydrogen peroxide production of white blood cells in vivo.
The rat sepsis model was developed by continuous infusion of endotoxin (5 mg/kg/hour) . Blood pressure was recorded by left femoral arterial intubation. After 2 hours, we visualized the hydrogen peroxide production by intravenous administration of 2', 7'-dichlorofluorescin diacetate, and observed the pulmonary microcirculation, using a fluorescence microscope, a SIT TV camera, and a videotape recorder. We calculated the hydrogen peroxide production by image analysis after the experiment. E5 (6 mg/kg), which was injected 1 hour before, significantly prevented the hypotension induced by the endotoxin. We found that the amount of fluorescence significantly decreased in the E5 pretreatment group compared with the endotoxin group.
In conclusion, E5 pretreatment inhibits hypotension and hydrogen peroxide production in the intact pulmonary microcirculation associated with endotoxin in a rat sepsis model.

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The effect of methotrexate on bone metabolism was investigated in adjuvant arthritis in rats (AA rats) . Methotrexate was orally administered to rats for 28 days from the next day after adjuvant inoculation. Twenty four-hour urine samples were obtained before sacrifice, pyridinoline (PY) and deoxypyridinoline (DPY), and creatinine concentrations in urine were measured by HPLC and the alkaline picronate method, respectively. Urinary PY and DPY in AA rats were increased 3.8 and 2.7 times that of age-matched controls, respectively. Doses of 0.05, 0.1 and 0.2 mg/kg caused a dose-dependent inhibition of the inflammatory parameters (fibrinogen, A/G) and the excretion of urinary PY and DPY in AA rats. Indomethacin (1 mg/kg, p. o.) had a significant inhibitory effect on both inflammatory parameters and urinary PY, but not on DPY. Moreover, the fourth lumbar of vertebra was used for determination of morphological changes. The trabecular number in the vertebra in the AA rats significantly decreased in comparison with that of age-matched normal. Methotrexate (0.05, 0.1 and 0.2 mg/kg) dose- dependently and completely inhibited severe changes observed in the vertebra of AA rats, while indomethacin only partly inhibited these changes. The present study indicates that MTX can prevent bone destruction in AA rats and measurement of urinary DPY is a useful marker for examination the effect of drugs on bone destruction.

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The effect of ciprofloxacin (CPFX), one of newquinolones, on histamine release from human dispersed skin mast cells and rat peritoneal mast cells was evaluated in vitro. It was demonstrated that CPFX did not induce significant histamine release from the relevant cells with the concentrations below 20μg/ml, indicating that CPFX itself does not activate mast cells directly as a nonimmunological stimuli with the dosis employed clinically.

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In this study, we measured nitric oxide (NO) concentration in exhaled air before and after attacks in asthmatics, and during exercise in healthy and asthmatic subjects.
The results revealed that NO concentration significantly increased after asthmatic attacks as compared with that before attacks, and that NO showed a tendency to decrease during exercise in healthy subjects whereas it increased in asthmatics. The decrease in healthy subjects depended on increased minute ventilation and the increase in asthmatics seemed to be based on induction of chemical mediators by exercise.
We conclude that NO concentration in exhaled air changes according to asthmatic states.

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