We have identified a novel ligand for CD44, a cell surface glycoprotein implicat ed in tumor metastasis and lymphocyte homing. When a mouse T cell line CTLL-2 was transfected with cDNA encoding a hemopoietic form of mouse CD44, CTLL-2 cells exhibited a new self-abhesive phenotype, forming large aggregates. The aggregation was blocked by neutralizing antiCD44 monoclonal antibody but unaffected by hyaluronidase, indicating the involvement of CD44 and its nonhyaluronate ligand in the cell aggregation. The ability to induce CD44-dependent aggregation was found in culture supernatants of CTLL-2 and its CD44 transfectants. The use of soluble CD44 chimeric protein revealed that CTLL-2 and its transfectants synthesized a large-molecular weight protein (gp600) which bound specifically to CD44.
Biochemical analyses revealed that the gp600 is a non-hyaluronate proteoglycan termed serglycin which is stored in and shed from secretary granules of NK and myeloid cells.

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Interleukin 1 (IL-1), interleukin 6 (IL-6) and tumor necrosis factor α (TNFα) are proinflammatory cytokines which control many features of physiological and inflammatory responses. We studied the modulatory effect of Sairei-to on the production of three cytokines from peritoneal macrophages of mice. The macrophages were cultivated with LPS and Sairei-to or Sairei-to alone for 20 hrs and then each cytokine in the cultured supernatants was estimated by the bioassay or ELISA. Sairei-to blocked the LPS-induced generation of all cytokines, and this effect was found to be dosedependent. The highest dosage (1, 000 μg/ml) of Sairei-to without LPS induced thein vitroproduction of three cytokines. These findings were supported by the analysis of cytokine mRNA expressions. The LPS-stimulated macrophages from the mice, orally pretreated with Sairei-to for 7 days, did not produce TNFα, when cultivated with and without Sairei-to. In contrast, thein vitroIL-6 generation was significantly induced by the macrophages from the Sairei-to-pretreated mice in spite of the absence of LPS.
These results may demonstrate the dichotomy of pharmacological effects of Sairei-to on the cytokine production from murine macrophages because Sairei-to blocks the cytokine production in macrophages stimulated with LPSin vitro, whereas Sairei-to by itself induces cytokine production in macrophages.

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Chronic hypoxic exposure causes pulmonary hypertension and right ventricular hypertrophy associated with pulmonary vascular remodeling in rats. Since platelet-activating factor (PAF) production has been shown to increase during hypoxia, and since PAF contributes to pulmonary hypertension, we hypothesized that increased PAF during hypoxia might play a role in the development of pulmonary hypertension induced by hypoxic exposure, and examined the effect of PAF-antagonists on hypoxia-induced pulmonary hypertension. Pulmonary hypertension and right ventricular hypertrophy developed at 3 weeks of hypoxic exposure. Treatment with WEB 2170 or BN 50739, specific PAF-antagonists significantly reduced hypoxia-induced pulmonary hypertension. Hypoxia-induced pulmonary hypertension was associated with an increase in the vessel wall thickness of the muscular arteries. In WEB 2170-treated rats, this change was significantly less severe than that observed in untreated chronically hypoxic rats. These results indicate that the PAF-antagonists inhibit the development of pulmonary hypertension induced by chronic hypoxic exposure and suggest a role for PAF in the remodeling process of pulmonary vessels induced by chronic hypoxia in rats.

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To elucidate the role of neutrophil elatsase on joint destruction in rheumatoid arthritis (RA), the following experiments were performed.
1. A specific inhibitor of neutrophil elastase (ONO-5046) was injected into the knee joint three times a week for three weeks in heat-killed E. coli O: 14 induced arthritis in 10 rabbits, which were prepared as RA models. As a result, the development of pathological changes in the synovial membrane and cartilage was found to be suppressed.
2. Neutrophil elastase dissolved in saline was injected into the knee joint of rabbits for three to nine weeks in order to examine its effect on the joint histologically. A moderate degree of synovitis was observed in all the synovial membranes. In the long-term groups, the cartilage also degenerated.
These findings suggested that neutrophil elastase should play a role as one of the etiologies to the joint destructive process of RA, and that the clinical application of its inhibitors might be expected.

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Rheumatoid arthritis (RA) is a systemic and chronic disorder involving joint damage. Recent studies have demonstrated changes in bone metabolism in patients with RA. Therefore, the aim of this study was to investigate the effects of some therapeutic drugs for RA on bone resorptionin vitro. The bone resorption was studied by measuring of calcium contents in medium released from mouse calvaria in tissue culture. Parathyroid hormone (PTH) and recombinant human interleukin 1β (rhIL-1β), bone resorting factor, was used in this experiment. The calcium contents in the medium with mouse calvaria was significantly increased by the presence of PTH (10-100nM) and rhIL-1β (3 -30U/ml) in a dose dependent manner. The increase in the medium calcium contents induced by PTH was inhibited by the coexistence of cyclosporin (l0μM) and methotrexate (1-10μM) whereas was not blocked by the presence of 10μM sulfasalazine, aurothioglucose, indomethacin, diclofenac Na, ketoprofen and bucillamine. However, rhIL-1β stimulating bone resorption was inhibited completely by indomethacin, diclofenac Na, ketoprofen and cyclosporin at 10μM. However sulfasalazine, aurothioglucose and methotrexate had not effect on rhIL-1β stimulating calcium release. At 10μM, bucillamine tend to enhance the calcium release from mouse calvaria by rh1L-1β. Furthermore, the calcium release by PTH and rhIL-1β was strongly prevented by bafilomycin A₁ in doses between 1 nM and 10 nM.
The effect of therapeutic drugs for RA was investigated in cloned osteoblast-like osteosarcoma cell (Saos-2) . Cells were cultured for 1 day at 37°C in a CO₂incubator in plastic dishes containing McCoy's 5 A medium supplemented with 10% fetal bovine serum (FCS) . After the cultures, the medium exchanged for FCS-free medium containing upper drugs and the cells were cultured further for 72h. Alkaline phosphatase (ALP) activity and DNA content in Saos-2 cells was significantly inhibited by cyclosporin (10μM) . Also, only DNA content in Saos-2 cells was significantly inhibited by methotrexate (10μM) . However, diclofenac Na, indomethacin, ketoprofen, bucillamine, sulfasalazine and aurothioglucose at the concentration of 10μM did not effect on ALP activity and DNA contents in the cells.
These results indicated that NSAIDs had an inhibitory effects of bone resorption by rhIL-1β rather than PTH, but DMARDs had not directly inhibition by them, and, immunosuppresser, cyclosporine and methotrexate, had an inhibitory effects of bone resorption by PTH and/or rhIL-1β, but these two drugs also prevented osteoblastic function. From a clinical standpoint, the development of inhibitory drugs for bone resorption blocked or reduced the rate of progression of bone damage in RA without the inhibitory effect of osteoblast may be important.

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Oral gold compound, auranofin (AF), is clinically useful for the treatment of patients with rheumatoid arthritis (RA) as one of the disease modifying antirheumatic drugs, although its mechanism of action is not determined yet. In the present study, the effects of auranofin on production of soluble IL-2 receptor (sIL-2R), IL-4, interferon γ (IFN γ) and IL-6 by mononuclear cells (MNC) were studied.
MNC were isolated from the peripheral blood of 4 RA patients. MNC of each patients were cultured with or without AF for 24 hrs and the supernatants obtained by centrifugation were measured for sIL-2R, IFNγ, IL-4 and IL-6 by ELISA kits.
AF at the concentrations of 3μg/ml significantly inhibited production of sIL-2R, IL-4 and IL-6 in RA MNC. On the other hand, the inhibitory effects by gold sodium thiomalate and D-penicillamine were not significant.
The inhibition by AF of sIL-2R, IL-4 and IL-6 production by RA MNC may be one of the mechanisms by which AF shows clinical efficacy.

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Thrombin-antithrombin III complex (TAT) in plasma is a specific parameter for a latent activation of the clotting pathway. The concentration of the plasma TAT elevated in disseminated intravascular coagulation, deep vein thrombosis, pulmonary embolism, myocardial infarction, infectious diseases and malignant diseases. We serially monitored the plasma level of TAT in four collagen disease patients with active interstitial pneumonia. The degree of TAT in two patients who recovered from the interstitial pneumonia was decreased after the methylprednisolone pulse therapy. In contrast, the concentration of TAT in the two deceased patients was elevated. The concentration of plasma TAT may be a sensitive parameter for monitoring the disease activity of interstitial pneumonia in collagen diseases.

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Histamine is one of the important mediators that causes a variety of allergic inflammatory responses in the airway. In the present study, to determine the effect of histamine on ion transport function across the airway mucosa, we measured transepithelial potential difference (PD) of rabbit tracheal mucosa under open-circuit conditionsin vivo. A high impedance voltmeter was used to measure PD between a fluid-filled and perfused recording bridge located on the airway surface and a reference bridge in the subcutaneous space. Addition of histamine to the perfusate produced a biphasic response of PD consisting of a rapid decrease within 15 sec and the subsequent plateau, which was followed by a sustained increase after 5 min of addition. Pretreatment of tracheal mucosa with the Na channel blocker amiloride greatly inhibited the early phase reduction of PD in response to histamine, but had no effect on the late phase elevation. On the other hand, pretreatment with the Cl channel blocker diphenylamine-2-carboxylate inhibited the late phase increase of PD completely.
These results indicate that early and late responses of PD are dependent on Na and Cl, respectivly, and suggest that histamine may inhibit Na absorption and stimulate Cl secretion in the airway mucosa.

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Correlations between the amounts ofH.pylori (HP) or the titers of anti-HP Ab in the sera of the patients with chronic gastritis and neutrophil infiltration in the gastric specimens were studied. HP was detected in 57% (24/42) of the patients with chronic gastritis. Neutrophil infiltration in lamina propria, epithelial cell layer and mucous layer were abundant according to the amount of HP in the gastric specimens (P<0.01) . In the HP (+) group by culture, titers of anti-HP Ab of sera were higher than in HP (-) group (P<0.02) .
By the ultrastructural studies, 60% of HP were floating in the mucous layer. On the other hand, 30% of HP attached to the gastric epithelial cells. In cases HP were observed frequently, vacuolar degeneration of the epithelial cells and loosening of tight junctions or bacterial invasion in the cells were common.
In conclusion, direct influences of HP to the gastric epithelial cells or their environment such as neutrophil infiltration was detected in the HP (+) chronic gastritis.

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Cepharanthin ointment (2%) was investigated for its anti-inflammatory activity on the chronic adjuvant arthritis by local application in rats and its suppressive effect on the production of tumor necrosis factor-α (TNFα) . TNFα, an important cytokine in host defense mechanisms, is also implied in many acute and chronic disease states by its overproduction. Therefore, the inhibition of TNFα overproduction leads to suppression of inflammation.
Cepharanthin ointment inhibited markedly on the development of the chronic adjuvant arthritis in rats. And also, this drug significantly reduced the level of TNFα in which peaked 2 hr after LPS injection in the BCG treated mice. On the other hand, systemic side effects such as decrease in weight of adrental or thymus and body weight loss were most evident in the case of untreated control and lower with cepharanthin ointment. This study shows that cepharanthin ointment was effective on the inflammation at least in part by suppressing TNFα production.

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The anti-inflammatory activity of cepharanthin ointment (2%) was investigated by local application in mice and rats. The inhibitory activities of cephar-anthin ointment against the acute carrageenin-induced hind paw edema in mice, and edema induced by a drop of croton oil into the mouse ear were seen potently. Cepharanthin ointment also inhibited significantly the superficial inflammation such as increased vascular permeability induced by intradermal injection of histamine in rats. Cepharanthin ointment, like steroid and nonsteroid action, inhibited both the early phase of hind paw edema produced by mixed phlogistics and the delayed phase mediated by carrageenin and kaolin in mice. Therapeutic effect of cepharanthin ointment on the carrageenin-kaolin-induced hind paw edema in mice was observed. From these results, it was suggested that cepharanthin ointment was effective on various types of inflammation and showed particularly potent inhibitory activity against acute inflammation. These findings suggest that the mode of action of cepharanthin ointment is unique drugs similar to that of both steroidal and non-steroidal anti-inflammatory actions.

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