Nobuaki Maeno

Expression of vascular endothelial growth factor in sera and lymph nodes of the plasma cell type of Castleman's disease

To evaluate the possible involvement of vascular endothelial growth factor (VEGF) in the pathogenesis of Castlemans disease, we studied VEGF levels in sera and supernatants of cultured lymph nodes from two patients with the plasma cell type of Castlemans disease, and analysed the expression of VEGF immunohistochemically in the lymph nodes. Clinically, one patient was classified as the localized type and the other as the multicentric type. Histologically, mature plasma cells and hyalinized vessels were prominent in the interfollicular region. The VEGF levels of the sera and the supernatants of cultured lymph nodes of both patients were higher than those of normal controls. VEGF was strongly expressed in plasma cells in the interfollicular region of the lymph nodes of both patients, but rarely in normal lymph nodes. Our results suggest that VEGF may be involved in the marked vascular proliferation in the interfollicular region of the lymph nodes of the plasma cell type of Castlemans disease.

Increased Serum Levels of Vascular Endothelial Growth Factor in Kawasaki Disease

Vascular endothelial growth factor (VEGF) is an angiogenic mitogen that specifically targets vascular endothelial cells. The objective of this study was to evaluate the role of VEGF in Kawasaki disease (KD), the most common cause of systemic vasculitis in childhood. Serum VEGF levels were measured by ELISA in 22 patients with KD, 22 febrile children with infection, and 19 healthy children. Samples from KD patients were divided into three groups: acute stage (n = 20), subacute stage (n = 13), and convalescent stage (n = 15). The results showed that KD patients in the acute and subacute stages had significantly higher levels of VEGF than did patients with infectious diseases and the healthy control subjects. When compared with the VEGF levels of patients with and without coronary artery lesions (CAL), significantly higher levels of VEGF were observed in the subacute stage in patients with CAL and in patients without CAL in the acute stage. Serial examination revealed that the serum VEGF levels in KD patients with CAL increased from a relatively low level in the acute stage to an extremely high level in the subacute stage. In contrast, patients without CAL were found to have extremely high levels of VEGF only in the acute stage of KD. In KD patients, the serum VEGF levels did not correlate with the inflammatory markers and clinical symptoms. Our results raise the possibility that VEGF is involved in the pathogenesis of KD, especially in the development of CAL. Further study is needed to clarify the biologic effect of VEGF on coronary arteries in KD.

A promoter haplotype of the interleukin-18 gene is associated with juvenile idiopathic arthritis in the Japanese population.

Recently, we reported that genetic polymorphisms within the human IL18 gene were associated with disease susceptibility to adult-onset Stills disease (AOSD), which is characterized by extraordinarily high serum levels of IL-18. Because high serum IL-18 induction has also been observed in the systemic type of juvenile idiopathic arthritis (JIA), we investigated whether similar genetic skewing is present in this disease. Three haplotypes, S01, S02, and S03, composed of 13 genetic polymorphisms covering two distinct promoter regions, were determined for 33 JIA patients, including 17 with systemic JIA, 10 with polyarthritis, and 6 with oligoarthritis. Haplotypes were also analyzed for 28 AOSD patients, 164 rheumatoid arthritis (RA) patients, 102 patients with collagen diseases, and 173 healthy control subjects. The frequency of individuals carrying a diplotype configuration (a combination of two haplotypes) of S01/S01 was significantly higher in the JIA patients, including all subgroups, than in the healthy controls (P = 0.0045, Fischer exact probability test; odds ratio (OR) = 3.55, 95% confidence interval (CI) = 1.55–8.14). In patients with systemic JIA, its frequency did not differ statistically from that of normal controls. Nevertheless, it is possible that haplotype S01 is associated with the phenotype of high IL-18 production in systemic JIA because the patients carrying S01/S01 showed significantly higher serum IL-18 levels compared with patients with other diplotype configurations (P = 0.017, Mann-Whitney U test). We confirmed that the frequency of the diplotype configuration of S01/S01 was significantly higher in AOSD patients than in healthy control subjects (P = 0.011, OR = 3.45, 95% CI = 1.42–8.36). Furthermore, the RA patients were also more predisposed to have S01/S01 (P = 0.018, OR = 2.00, 95% CI = 1.14–3.50) than the healthy control subjects, whereas the patients with collagen diseases did not. In summary, the diplotype configuration of S01/S01 was associated with susceptibility to JIA as well as AOSD and RA, and linked to significantly higher IL-18 production in systemic JIA. Possession of the diplotype configuration of S01/S01 would be one of the genetic risk factors for susceptibility to arthritis in the Japanese population.

Clinical features of Japanese children and adolescents with systemic lupus erythematosus: results of 1980-1994 survey.

Marked advances have been made in the past decade in the management of adults with systemic lupus erythematosus (SLE). Therefore, a nationwide retrospective survey was conducted between 1980 and 1994 to investigate the clinical manifestations of SLE in Japanese children and adolescents. Questionnaires were sent to 340 hospitals. Of 405 patients reported by 176 hospitals, 373 patients, diagnosed by the criteria established by the Pediatric Study Group of the Japanese Ministry of Health and Welfare in 1985, were enrolled in the study. Forty‐nine of the 354 patients (13.8%) had relatives with a connective tissue disease within the third degree of consanguinity. The frequent manifestations in 373 patients were the presence of antinuclear antibody (98.9%), immunologic disorders (93.0%), hypocomplementemia (87.1%), malar rash (79.6%) and fever (74.0%). Lupus nephritis was present in 148 of the 309 patients (47.9%) at their first visit to a clinic, and 261 of the 373 patients (70.0%) developed renal involvement during the observation period. Of 370 patients, 92 patients (24.9%) exhibited central nervous system lupus. Of 368 patients, 192 patients (52.2%) were treated by methylprednisolone pulse therapy and 148 patients (40.2%) received immunosuppressants in combination with steroid therapy at some stage during the observation period. Survival rate at 5 years from onset was 95.9%. Management of infection, coagulopathies, and central nervous system involvement is essential to improve the prognosis of SLE in Japanese children and adolescents.

A heat-stable component of Bartonella henselae upregulates intercellular adhesion molecule-1 expression on vascular endothelial cells

Bartonella henselae upregulated the expression of intercellular adhesion molecule‐1 (ICAM‐1) on human umbilical vein endothelial cells (HUVECs). The induction level of ICAM‐1 depended on the inoculation bacterial dose. ICAM‐1 expression began increasing 4 h after infection and reached a sustained peak beginning at 12 h after B. henselae infection; this time course was similar to that of lipopolysaccharide (LPS) of Escherichia coli. The stimulatory effect was abolished when live B. henselae were separated from HUVECs by a filter membrane. The nonpiliated strain, which is unable to invade endothelial cells, induced ICAM‐1 expression to the same extent as the piliated strain. Inactivation of B. henselae by ultraviolet (UV) irradiation, heat (56 °C, 30 min), or sonication did not alter its stimulatory activity. Polymyxin B, which strongly inhibited the effect of LPS, did not exert any influence on the stimulatory activity of B. henselae. Furthermore, the effect of sonicated B. henselae was not inhibited even by boiling, which was also the case with LPS. Our data suggest that some heat‐stable component of B. henselae binds to the endothelial cell surface, inducing ICAM‐1 expression. Though the participation of LPS could not be completely ruled out, we suppose that some unidentified heat‐stable proteins, lipids, or polysaccharides may be the stimulatory factor(s). The ability of B. henselae to enhance the expression of adhesion molecules on endothelial cells may be an important mechanism in the pathogenesis of B. henselae infection.

Serum Levels of Interleukin-18 Are Elevated in the Subacute Phase of Kawasaki Syndrome

Background: Elevations of various cytokines, including Th1 and Th2 cytokines, have been reported in the acute phase of Kawasaki syndrome (KS). As interleukin (IL)-18 plays an important role in the Th1 cell response, investigating the relevance of IL-18 in KS should be helpful in determining the pathophysiology of KS. Therefore, we examined the IL-18 values in KS. Methods: Serum IL-18 values were measured by an enzyme-linked immunosorbent assay. Samples were obtained from 41 patients in the acute and subacute phase of KS, 35 age-matched febrile controls and 13 afebrile controls. Results: No difference was observed in the values of white blood cell counts or C-reactive protein between acute-phase KS patients and febrile controls. On the contrary, acute-phase KS patients showed a significantly lower mean IL-18 value (398 ± 206 pg/ml) than that of febrile controls (584 ± 307 pg/ml) (p = 0.006). Subacute-phase KS patients showed a significantly elevated level of IL-18 (517 ± 276 pg/ml) compared to acute-phase patients (p = 0.0008). The IL-18 values in the subacute-phase patients showed a significant positive correlation with the duration of fever (r = 0.427, p = 0.0055) and also with the presence of coronary artery abnormalities (r = 0.332, p = 0.0340). The incidence of elevated IL-18 values in the subacute-phase patients was significantly higher than that in the afebrile controls (p = 0.048). Conclusions: Patients with KS showed normal IL-18 values in the acute phase and elevated values in the subacute phase. IL-18 pathways were activated in the subacute phase of KS, and subacute IL-18 values might be reflected in the severity of KS.

Diagnostic significance of increased serum hyaluronic acid in juvenile rheumatoid arthritis

Background : We have previously reported that serum levels of hyaluronic acid (HA) objectively reflect the severity of arthritis in juvenile rheumatoid arthritis (JRA). However, clear diagnostic standards do not exist for JRA; it is difficult to evaluate arthritis in children, particularly in small children and the diagnostic criteria for JRA requires an exclusion of several diseases. Therefore, if a specific test finding associated with JRA could be established, it would enable general pediatricians to make an objective diagnosis.

Immune response to a laminin-binding protein (Lmb) in group A streptococcal infection

Abstract  Background : A laminin‐binding protein (Lmb) similar to that of group B streptococcus is conserved in group A streptococcus (GAS) and has a role in adhesion of GAS to epithelial cells. The role of this protein is yet to be clarified in disease process and thus, it is important to know its role in binding of GAS to laminin and the immunogenic response against it in patients related with GAS infection.

Efficacy of mizoribine in the treatment of systemic lupus erythematosus in children

Abstract Background : Mizoribine (MZR) is a novel immunosuppressant developed in Japan. As MZR is reported to be less toxic than other cytotoxic drugs, it is frequently used in Japan in the treatment of adult patients with rheumatoid arthritis or lupus nephritis. The objective of this study was to evaluate the efficacy of MZR in children with SLE. Nine female children with lupus nephritis who had undergone renal biopsy before starting MZR, were involved in this study. Their mean disease duration was 4.8 years at the time MZR treatment was initiated. Patients who had received intensive medications, such as methyl‐prednisolone pulse therapy, intravenous cyclophosphamide pulse therapy, and/or other immunosuppressants, within the 4 months prior to the start of the study, were excluded.

CD14-Mediated Induction of Interleukin-8 and Monocyte Chemoattractant Protein-1 by a Heat-Resistant Constituent of Porphyromonas gingivalis in Endothelial Cells

Viable and inactivated Porphyromonas gingivalis dose‐dependently induced interleukin‐8 (IL‐8) and monocyte chemoattractant protein‐1 (MCP‐1) secretion in human umbilical vein endothelial cells (HUVECs). The inactivated P. gingivalis, in comparison with viable bacteria, tended to enhance the production of both chemokines more strongly. The production of MCP‐1 protein began increasing immediately after stimulation by P. gingivalis, and there was a nearly linear increase from 0 to 8 h of incubation, whereas IL‐8 production showed a linear increase between 4 and 12 h of incubation. The IL‐8 and MCP‐1 mRNA expressions in HUVECs as determined by reverse transcriptase‐polymerase chain reaction (RT‐PCR) or Quantikine mRNA colorimetric quantification kits were found to be enhanced by P. gingivalis. Furthermore, the time courses of IL‐8 and MCP‐1 mRNA expressions were in accordance with those of protein production. Addition of polymyxin B or boiling did not weaken the stimulatory effect of P. gingivalis, which inhibited the effect of Escherichia coli lipopolysaccharide (E. coli LPS) and tumour necrosis factor‐α (TNF‐α), respectively. In contrast, the induction of IL‐8 and MCP‐1 by P. gingivalis was significantly reduced by anti‐CD14 antibody. Our results suggest that some heat‐stable component of P. gingivalis, including LPS, may be responsible for the induction of IL‐8 and MCP‐1 in HUVECs by a CD14‐dependent mechanism. These effects might be involved in the accumulation and activation of neutrophils and monocytes at an early stage of the periodontal pathogenesis.