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The susceptibility of congenitally anemic, and mast cell deficient W/Wv mice to infection with Strongyloides ratti was examined. After a primary infection, W/Wv mice showed greater and more persistent peak larval counts than did normal littermates. Worm expulsion was also slower in W/Wv mice than in +/+ mice. Furthermore, difference in susceptibility was expressed as early as 24 h after infection, suggesting not only that protective mechanisms of the gut but also of the connective tissue were defective in W/Wv mice. Reconstitution with bone marrow or spleen cells from +/+ mice was effective in restoring the protective response in W/Wv mice, whereas thymocytes or mesenteric lymph nodes had no effect. Both connective tissue and mucosal mast cells were repaired in W/Wv mice after marrow reconstitution and infection. Since relatively long incubation period was required for the expression of such reconstituting activities, bone marrow cells seem to contain precursor cells of the effector and/or regulator cells.

Background: Several lines of in vitro and in vivo studies have demonstrated that interleukin-18 (IL-18) shows both antiallergic and allergy-promoting activities. But its expression in allergic diseases remains unknown. Methods: Serum IL-18 levels from atopic dermatitis (AD) model mice, NC/Nga and control mice and from patients with AD and healthy volunteers were measured by ELISA. The relationship between IL-18 levels and serum IgE levels or clinical severity was also examined. Results: Serum IL-18 levels from NC/Nga mice were significantly increased compared to those from control mice. The elevation of IL-18 in the sera was observed prior to the onset and during the development of dermatitis in NC/Nga mice. In addition, IL-18 levels in the sera from patients with AD were significantly (p < 0.05) elevated compared to those from healthy volunteers. However, serum IL-18 levels tended to correlate negatively with serum IgE levels in patients with AD and NC/Nga mice. Conclusion: IL-18 is overexpressed in AD.

In an attempt to reveal the role of antigen-laden marginal metallophil (MM) and other macrophages in the intrasplenic immune response of a specific B-cell lineage to a thymus-independent type-2 antigen (Ficoll conjugated with fluorescein isothiocyanate), simultaneous immunohistological observations of the involved cells were performed in the rat. By newly established methods of double or triple immunostainings, time-kinetics of the following parameters were studied and compared: (1) the antigen, (2) the specific antibody-forming cells (AFC) directed to the fluorescein-isothiocyanate determinant, (3) proliferating cells labeled with 5-bromo-2'-deoxyuridine (BrdU), and (4) macrophage subpopulations recognized by monoclonal antibodies (ED2 and ED3). The antigen localized stably not only in the marginal-zone macrophages but also in the MM except around the follicular area. The increase of BrdU-positive cells was observed from day 2 up to day 4 after antigen injection mostly in the periphery of the periarterial lymphoid sheath (outer PALS), which indicated antigen-induced proliferation. As a novel finding, the majority of AFC, both BrdU-positive and -negative, were either closely associated with the antigen-laden MM, or forming cell clusters with ED2-positive macrophages in the outer PALS. In contrast, there were very few AFC in juxtaposition to antigen-free MM in the follicular area or the antigen-laden marginal zone macrophages. The results led to the proposal of a hypothesis that the antigen-laden MM together with ED2-positive macrophages constitute an immunoproliferative microenvironment for the plasmacellular reaction by accumulating the antigen-specific B-cell lineage and promoting these cells to differentiate into the AFC and to proliferate in the outer PALS.

These observations suggest that persimmon leaf extract or the flavonoid astragalin may be alternative substances for the management of AD.

Simultaneous fiber-failure (SFF) model that determines tensile strengths for various systems of unidirectional composites comprehensively is presented. The SFF derives the strength of unidirectional composites as a function of the single-fiber strength distribution, interfacial shear strength, and matrix strength. The point of the SFF is that a fiber group which is considered to be experiencing simultaneous fiber failures triggered by neighboring fiber failures is assumed to fail when the weakest fiber in the fiber group fails. We discuss a method to determine the magnitude of the fiber group for various systems of composites on a basis of whether a crack located near a bi-materials interface penetrates into another material or deflects along the interface. The SFF is established by integrating the magnitude of the simultaneous fiber failures into the conventional Global load sharing model.

Many patients with atopic dermatitis are dissatisfied with conventional treatments based on topical steroids and have experienced some traditional remedies and alternative therapies. However, most of such therapies have not been evaluated scientifically and clinically by specialists. This study was designed to assess whether a certain vegetarian diet might be effective for atopic dermatitis and if so, to identify the mechanisms of this remedy through analyses of immunological parameters. An open-trial study was carried out in twenty patients with atopic dermatitis. An improvement of dermatitis was evaluated by SCORAD index and serological and immunological parameters were monitored. After a twomonth treatment, the severity of dermatitis was strikingly inhibited, as assessed by SCORAD index and serological parameters including LDH5 activity and a number of peripheral eosinophils. A sharp reduction in eosinophils and neutrophils was observed prior to improvement in the skin inflammation. In addition, PGE2 production by peripheral blood mononuclear cells was reduced by this treatment. In contrast, serum IgE levels did not change during the same period. Although this study is an open-trial one, it suggests that this treatment may be useful for the treatment of adult patients with severe atopic dermatitis.