Glomerular infiltration by neutrophils is a hallmark of acute glomerulonephritis. The pathophysiological role of interleukin-8 (IL-8), a potent neutrophil chemotactic cytokine (chemokine), was explored in an animal model of acute immune complex-mediated glomerulonephritis by administering a neutralizing antibody against IL-8. Repeated injection of bovine serum albumin (BSA) into rabbits caused the deposition of immune complexes consisting of BSA and rabbit IgG in glomeruli. Histological analyses revealed a small but significant number of neutrophils in glomeruli and the fusion of epithelial cell foot processes. Concomitantly, urinary levels of protein and albumin increased markedly (3.20±0.97 and 1.39±0.53 mg/hr, respectively) compared with those of untreated animals (0.77±0.21 and 0.01±0.01 mg/hr, respectively) . Anti-IL-8 antibody treatment decreased the number of neutrophils in glomeruli by 40% and dramatically prevented the fusion of epithelial cell foot process. Furthermore, treatment with anti-IL-8 antibody completely normalized the urinary levels of protein and albumin (0.89±0.15 and 0.02±0.01 mg/hr, respectively) . These results indicated that IL-8 participated in the impairment of renal functions in experimental acute immune complex-mediated glomerulonephritis through activating as well as recruiting neutrophils. Here, we will overview the roles of chemokine in human diseases and discuss our therapeutic approaches to intervene inflammation targeting chemokine.

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Periodontitis is infectious disease by periodontopathic bacteria and characterized by gingival connective tissue loss, periodontal pocket formation and alveolar bone resorption. Unbalance of local immune responses may cause onset and progression of periodontitis. Gingival crevicular fluid (GCF) from the pocket of periodontitis patients contains immuno-competent cells, namely, polymorphonuclear leukocytes, lymphocytes, and macrophages.
Cell surface expression of Fcγ receptor II, III in GCF-polymorphonuclear leukocytes decreased in contrast to increase of complement receptor 3 as compared with those of autologous peripheral blood-polymorphonuclear leukocytes. Transcript levels of Fcγ receptor III and complement receptor 1, 3 significantly decreased. These phenomena may induce impaired phagocytosis of GCF-polymorphonuclear leukocytes and progression of periodontitis.
Regarding for GCF-lymphocytes, decreased T cell/B cell ratio and activated helper T cells and B cells were observed as compared with autologous peripheral blood-lymphocytes. ICAM-1 positive pocket epithelium and LFA-1 expression of GCF-lymphocytes may be related to cell exudation from connective tissue to gingival crevice.
HIV gag protein p24 positive macrophages in GCF increased dramatically in AIDS patients with periodontitis. PCR and RT-PCR of GCF-leukocytes yielded positive signals of p 24, demonstrating viral integration and production. These findings could be considered as a within-mouth source of viral reservoir.
These characteristics of immuno-competent cells in GCF may reflect local immune responses of inflammatory gingival tissues.

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It has been postulated that disturbances of ionic homeostasis may determine the vulnerability of the heart to reperfusion-induced injury, and that reactive oxygen species produced during reperfusion, cause oxidant stress to membrane protein or lipid that leads to disturbances of ionic homeostasis and arrhythmias. To test this hypothesis, we studied the efficacies of various reactive oxygen species scavengers in reducing ischemia-reperfusion (I/R) -induced myocardial injury in isolated perfused rat hearts. The effect of in vitro free radical generating system consisting of hypoxanthine (hyX) and xanthine oxidase (XO) on sarcoplasmic reticulum (SR) function was also investigated. In I/R hearts, the contractile function and coronary flow were reduced; reperfusion with histidine or a cocktail of superoxide dismutase (SOD) -catalase-mannitol resulted in significant protection against the effect of I/R. The incidence of arrhythmias during reperfusion was 100% in I/R hearts; the duration of arrhythmias was shortened with histidine or with SOD-catalase-mannitol. The decreased duration of normal sinus rhythm in I/R hearts was also protected with histidine or SOD-catalase-mannitol. The SR function assessed by oxalate-supported Ca²⁺ uptake rate in cell free preparations in the presence or absence of ruthenium red, a selective SR Ca²⁺-release channel blocker, was depressed by exposure to hyX-XO reaction. The observed effect of hyX-XO was SOD-inhibitable and was protected by SOD-catalase-mannitol. In samples where the Ca²⁺-release channel was blocked with ruthenium red, no changes in Ca²⁺ uptake rates were noted after ischemia only; the Ca²⁺ uptake rates in the presence of ruthenium red decreased in samples from ischemia-reperfused hearts, suggesting Ca²⁺-release channel dysfunction caused by oxygen-derived free radicals generated during reperfusion. Exposure of isolated heavy SR to hyX-XO reaction produced potent increase in Ca²⁺ efflux; the effect of hyX-XO reaction was protected by SOD or by established optimal conditions for specific closure of heavy SR Ca²⁺-release channel by ryanodine. Based on these lines of results, we conclude that the action of reactive oxygen species (possibly, superoxide radicals or singlet molecular oxygen) may be mediated in part through SR Ca²⁺-release channel, thereby causing Ca²⁺ overload linked to arrhythmogenic electrophysiological changes.

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Defensin has been known as a major antimicrobial component of neutrophil granules. Recently, we have purified a novel cationic antibacterial polypeptide of 11 kDa (CAP11) from guinea pig neutrophilis. In this study, we have compared the biological activity and gene expression between CAP11 and defensin. When stimulated, CAP11 was extracellularly released from neutrophils, accompanied by the release of a specific granule component (lysozyme), whereas defensin was released, accompanied by the release of an azurophil granule component (β-glucoronidase) . Defensin modulated neutrophil functions such as adhesion, phagocytosis and superoxide anion generation. However, CAP11 did not affected the neutrophil functions. Both CAP11 and defensin possessed histamine-releasing activity for mast cells, but CAP11 was 10-fold less potent than defensins. CAP11 exhibited 8-fold more antibacterial activity against Escherichia coli than defensin, and the activity was retained even in the presence of physiological concentration of NaCl, although the activity of defensin was completely lost in the presence of NaCl. Sequence analysis of CAP11 cDNA showed that pre-prosequence of CAP11 was similar to the sequences of cathelicidin family polypeptides. Furthemore, in situ hybridization study revealed that CAP11 mRNA was highly expressed in metamyelocytes among bone marrow cells. In contrast, defensin mRNA was expressed in promyelocytes and myelocytes. Together these observations indicate that CAP11, a member of cathelicidin family, which is synthesized during the late stage of neutrophil maturation and stored possibly in the specific granules, is released from stimulated neutrophils and functions as an antibacterial molecule in the extracellular milieu, whereas defensin released from the azurophil granules likely participate in the modulation of neutrophil functions and mast cell histamine release.

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The effect of a monoclonal antibody against IL-4 (11B11) on oral tolerance was investigated. Oral tolerance was induced by feeding mice with hen egg lysozyme (HEL) before immunization with HEL. 11B11 was ip injected 30 min before oral administration of HEL. The results showed that the oral administration of HEL suppressed immune responses to the antigen including DTH responses, production of both isotypes of IgG 1 and IgG2a antibodies, and proliferation of lymph node cells in a dose-dependent manner. These suppression were associated with a marked reduction of IFN-γ secretion and a partial decrease in IL-4 production by lymphoid cells. The treatment of the tolerant animals with 11B11 significantly blocked the suppression of DTH responses, IgG2a antibody production, and proliferative responses as well as IFN-γ secretion. In contrast, the monoclonal antibody facilitated the suppression of anti-HEL IgG1 antibody production and IL-4 secretion. Thus, oral antigens appear to induce not only Th1 but also Th2 cell tolerance and the neutralizing IL-4 with anti-IL-4 antibodies seems to reverse the suppression of Th1 cell responses, while the antibodies further reduce Th2 cell responses in oral tolerance, indicating the implication of IL-4 in the oral tolerization of Th1 cells.

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Tumor necrosis factor (TNF) -α is present in synovial fluid of patients with rheumatoid arthritis. It induces the expression of chemotactic cytokines (chemokines) such as interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in synovial cells.
Based on our recent finding that reactive oxygen intermediates play important roles in mediating TNF-α action, we examined the effect of an antioxidant flavonoid, quercetin, on TNF-α-induced expression of IL-8 and MCP-1 in cultured human synovial cells. Quercetin suppressed the TNF-α-induced increase in the mRNAs for IL-8 and MCP-1 in a dose dependent manner. H₂O₂-mediated induction of these genes was also inhibited by quercetin. Electrophoretic mobility shift assays revealed that quercetin inhibited the activation of NF-κB by TNF-α.
These results demonstrate for the first time that quercetin suppresses TNF-α-mediated stimulation of IL-8 and MCP-1 expression, at least in part, by inhibiting the activation of NF-κB.

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Clinical usefulness of TS-110 against rheumatoid arthritis in long-term administration was evaluated in an open study.
1. A total of 134 subjects were included; 108 subjects (80.6%) were treated for 12 weeks or more, 82 subjects (61.2%) for 24 weeks or more, and 30 subjects (22.4%) for 48 weeks.
2. In the examination of the clinical evaluation items at final observation, there were significant improvement for number of painful and swallen joints, joint score, pain score and activities of daily living (upper limb), comparing at baseline.
3. In the patients' satisfaction rating, the rate of “satisfied” or better was found in 16.2% (12/74 cases) after 24 weeks, almost constant value of more than 20% was seen after 32 or more weeks, and the rate was 26.7% (8/30 cases) after 48 weeks.
According to evaluation of symptom-improvement by physicians, the rate of “improved” or better results was found in 33.3% (25/75 cases) after 24 weeks, more than 30% thereafter and 37.9% (11/29 cases) after 48 weeks.
4. With respect to the global improvement rating, the rate of “improved” or better results was found in 33.8% (25/74 cases) at the time after 24 weeks of administration and 40.0% (12/30 cases) after 48 weeks of administration. The final global improvement rate was 30.5% (36/118 cases) .
5. Sixty-four episodes of adverse drug reactions were found in 41 of 133 patents (30.8%), and every case was mild or moderate. Every abnormal change of clinical laboratory value of which causal relation to the trial drug could not be denied was handled as adverse drug reactions.
The incidence did not rise and the types of adverse drug reactions were not different with prolonging administration period.
6. Conerning the overall safety rating, the safety rate with “safe” was found in 85.3% (64/75 cases) at the time after 24 weeks of administration and 90.0% (27/30 cases) after 48 weeks of administration. The final overall safety rate was 69.2% (92/133 cases) .
7. As to the utility rating, the usefulness rate with “useful” or better was found in 36.5% (27/74 cases) at the time after 24 weeks of administration and 43.3% (13/34 cases) after 48 weeks of administration. The final usefulness rate was 26.8% (34/127 cases) .
In conclusion, TS-110 exhibited good efficacy and safety in a long-term administration against rheumatoid arthritis, and therefore, is considered to be a useful drug clinically.

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We compared TS-110 with a control drug, indomethacin, in a double blind study to evaluate clinical usefulness of TS-110 in rheumatoid arthritis. TS-110 (Group T) and indomethacin (Group I) were orally administered for 6 weeks at daily doses of 12 mg t.i.d. and 75 mg t.i.d., respectively.
1. Study drugs were administered to a total of 189 subjects (95 subjects in Group T and 94 in Group I) . A total of 183 subjects (91 in Group T and 92 in Group I) were included in ITT for efficacy, safety and usefulness.
2. No deviations were noted in background factors except for “sex” (p=0.0566) and “use of concomitant drugs” (p=0.0313) . Influences of the deviations on the improvement rating were tested by the Mantel-Haensel method, but no influences were noted.
3. With respect to the final overall improvement rating, the improvement rates with “improved” or better results were 29.7% (27/91 subjects) and 17.4% (16/92 subjects) in Groups T and I, respectively, demonstrating equivalent efficacy for Group T and I.
4. Incidences of adverse reactions were 19.8% (18/91 subjects) and 26.1% (24/92 subjects) in Groups T and I, respectively. According to symptoms, gastrointestinal symptoms were noted in 13 and 17 subjects in Groups T and I, respectively, hypersensitivity including anthema and itchiness was noted in one subject each in Groups T and I, mental and neurological symptoms such as dizziness and headache were observed in one subject in Group T and 11 subjects in Group I, and abnormal variations in clinical laboratory values were observed in 11 and 7 subjects in Groups T and I, respectively.
5. Concerning overall safety rating, the safety rates with the grading of “safe” were 80.2% (78/91 subjects) and 78.9% (68/92 subjects) in Groups T and I, respectively, demonstrating equivalent safety for Groups T and I.
6. As to utility rating, the usefulness rates with “useful” or better grading were 28.6% (26/91 subjects) and 15.2% (14/92 subjects) in Groups T and I, respectively, showing a significantly higher result for Group T than Group I (p=0.0289) .
7. With respect to other secondary evaluation parameters, the patient satisfaction rate with grading of “satisfied” or better on the final day of evaluation was significantly higher in Group T than in Group I (p=0.0166) .
In light of these results, TS-110 at dose of 12 mg/day has equivalent levels of efficacy and safety as indomethacin at dose of 75 mg/day against rheumatoid arthritis, in addition, TS-110 has been judged to be a clinically highly useful drug with respect to the patient satisfaction.

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