The intraperitoneal administration of CAWS (water-soluble extracellular polysaccharide fraction obtained from the culture supernatant of Candida albicans) to mice induces coronaritis similar to Kawasaki disease. We analyzed differences in the production of cytokines involved in the occurrence of coronary arteritis among mouse strains, C3H/HeN, C57BL/6, DBA/2 and CBA/J that were injected with CAWS at 4 mg/mouse for 5 consecutive days in the first week and the fifth week of administration. The incidence of arteritis was 100% in C57BL/6, C3H/HeN and DBA/2 mice, but only 10% in CBA/J mice. The coronary arteritis observed in DBA/2 mice was the most serious, with several mice expiring during the observation period. The CAWS-sensitive strains revealed increased levels of IL-6 and IFN-gamma during the course of a specific response to CAWS by spleen cells. In contrast, IL-10 levels were observed to increase markedly in CAWS-resistant CBA/J mice, but not the CAWS-sensitive strains. However, TNF-alpha levels were more elevated only in DBA/2 mice. The difference in disease development and cytokine production strongly suggests that the genetic background of the immune response to CAWS contributes to the occurrence of coronary arteritis.

Candida albicans is a medically important fungus which induces a disseminated candidasis and candidemia in immunocompromised hosts, and releases a polysaccharide fraction into the blood. We recently found that C. albicans released a water-soluble polysaccharide fraction (CAWS) into synthetic medium and demonstrated that CAWS was mainly composed of a complex of mannan and b b-glucan. In the murine system, CAWS showed a lethality resembling anaphylactic shock when administered i.v., and induced coronary arteritis similar to Kawasaki Disease (KD) when given i.p. In the present study, we examined the biological activity of CAWS in the cell culture and found the following: i) CAWS slightly induced production of IFN-g g and IL-6 by splenocytes at lower dose (ca. 10 m mg/ml), but at a higher dose strongly inhibited the proliferation of splenocytes induced by a B cell mitogen, lipopolysaccharide (LPS) and a T cell mitogen, concanavalin A. ii) The viability of these splenocytes monitored by propidium iodide staining was significantly reduced. iii) The addition of CAWS to a culture of monophage RAW264.7 cells significantly reduced cellular growth rate dose dependently. iv) The LPS-mediated synthesis of cytokines by RAW264.7 cells was significantly inhibited by CAWS. v) CAWS induced an aggregation of platelets in human platelet-rich plasma, and vi) CAWS inhibited the production of thrombomodulin by human umbilical endothelial cells and acted synergistically with TNF-a a. Thus, CAWS strongly inhibited the cellular functions of leukocytes in vitro, partly through direct cytotoxicity. The enhanced production in injured cells of the vascular endothelium would be related to the local inflammatory response in the coronary artery.

Patients are becoming increasingly susceptible to infectious diseases. Deep mycoses are grave infections that occur in compromised hosts including patients with hematopoietic malignant diseases such as leukemia and malignant tumors, or AIDS, and continue to be a serious problem despite the availability of advanced medical technology. 1)The fungal cell wall typically contains b-glucans as its main constituent, and b-glucans are detected in the blood of patients with deep mycoses. Measurements of blood b-glucan levels are universally employed for the early diagnosis of deep mycoses. [2][3][4][5] We obtained a water-soluble extracellular polysaccharide fraction (Candida albicans water-soluble fraction: CAWS) in the culture supernatant obtained by culturing Candida spp. in a completely synthetic medium. CAWS was found to be composed of a mannoprotein-b-glucan complex, to be able to activate limulus G factor, 6) to demonstrate an activating effect on vascular endothelial cells, platelets, and lymphocytes, and to demonstrate vasculitis-inducing activity when administered to mice.7-11) Moreover, CAWS caused an acute lethal reaction when administered intravenously to mice. The vasculitis was strongly related to the structure of the mannan moiety, and the activity was significantly reduced in the presence of a beta-1,2-linked mannosyl segment which was synthesized under specific conditions.12) We found that water-soluble fractions derived from other strains of C. albicans and other species including C. parapsilosis and Saccharomyces cerevisiae were also lethal when administered intravenously (i.v.) to mice, suggesting that the toxicity is universal among yeast-like fungi. However, the water-soluble fraction derived from C. albicans strain NBRC 1385 (CAWS) was the most lethal CAWS of these species and strains. In addition, the toxicity varied depending on the strain of mouse.13) These differences among strains are a good example of the genetic background of the host having a remarkable effect on the expression of pathogen-associated molecular patterns (PAMPs). Detailed analyses of the toxicity of CAWS at the molecular level will be useful for the development of therapies against pathogenic fungi.We describe herein the results of our study of the mechanism underlying the acute lethal reaction to CAWS, using various inhibitors. MATERIALS AND METHODS Experimental AnimalsMale C3H/HeN and ICR mice were acquired from Japan SLC. The animals were raised in a specific pathogen-free (SPF) environment. Mice were purchased at 5 weeks of age and used at 6 to 8 weeks of age.Fungi Candida albicans strain NBRC 1385 was acquired from NITE Biological Resource Center on Sabouraud agar medium (Difco, U.S.A.) at 25°C, and sub-cultured once every 3 months.Preparation of the C. albicans Water-Soluble Extracellular Polysaccharide Fraction (CAWS) CAWS was prepared from C. albicans strain NBRC 1385 in accordance with conventional methods.3) The culture was performed in 5 l of C-limiting medium (Sucrose; 10 g, (NH 4 ) 2 SO 4 ; 2 g, KH 2 PO 4 ; 2 g,...

Purpose.We investigated the effects of immuoglobulin(IG) upon experimental giant cell myocarditis in rats with an analysis of the phenotypic characteristic of myocardial dendritic cell(DC) and ribonuclease protein assay(RPA) for myocardial cytokines. Also, we investigated which fragment of IG, F(ab') 2 or Fc, was effetive to ameliorate myocarditis. Methods. Giant cell myocarditis was induced in rats by immunization of porcine cardiac myosin. Human intact IG(1g/kg/day) or human F(ab') 2 were administered intraperitoneally everyday until 21st day. Immunohistochemistry was performed to analyze the immunological behavior of DC and other infliltrating cells. In addition, we performed the RPA to confirm the anti-inflammatory action of IG. Results. Intact IG therapy significantly ameliorated experimental giant cell myocarditis macroscopically and microscopically, but F(ab') 2 fragments did not ameliorate significantly. Immunohistochemichal analysis showed that intact IG therapy suppressed DC expression both during the early and the fulminant phases. The RPA analysis revealed that intact IG therapy completely suppressed the mRNA expressions of interleukin(IL)-1, IL-6, and interferon-␥. Conclusions. The present study provides the evidence that IG therapy suppressed giant cell myocarditis due to the suppression of DC expression and the antiinflammatory actions, and that these effects may be mediated via the Fc portion of IG. 102 CANDIDA ALBICANS -EXTRACT CAUSING SYSTEMIC VASCULITIS IN MICE AS AN ANIMAL MODEL OF KAWASAKI DISEASEKei Takahashi, Toshiaki Oharaseki, Shiro Naoe, Hitomi Yamada, Hisao Murata, Megumi Wakayama, Kazutoshi Shibuya Department of Pathology, Ohashi Hospital, Toho University School of Medicine, Tokyo, JapanWe established a systemic vasculitis mice model involving coronary arteries using C. albicansExtract. This model is evaluated as an animal model of Kawasaki disease (KD) since this model has many similar points of KD. Careful study of this model may provide fundamental information that increases our understanding of the pathogenesis, natural history, and appropriate therapy of this illness. Yeast cells of a C. albicans strain isolated from the feces of a KD patient were incubated at 37°C for 72 hours. After harvest, the extract was obtained from the yeast cells using boiling water and KOH. C. albicans-Extract suspended in PBS was injected intraperitoneally for five consecutive days at 1st and 5th week. At 9th week, mice were killed under anesthesia, and then, histological features of the arteritis in various organs were observed. There was a difference in susceptibility to vasculitis between inbred mice strains. BALB/c, DBA/2 and CBA/J mice were resistant to vasculitis, however, C3H/HeN and C57BL/6 mice were classified as sensitive strains. Coronary arteries were most frequently involved; aorta and other medium-sized arteries in kidney, retroperitoneum, testis etc. were sometimes involved. Vasculitis was defined as a productive inflammation, which shows dense infiltrates of large mononuclear cells and ...

No abstract