Osamu Iizawa

Long-term follow-up study of changes in lipid peroxide levels and the activity of superoxide dismutase, catalase and glutathione peroxidase in mouse skin after acute and chronic UV irradiation.

Lipid peroxide levels, the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px), and the development of tanning in the skin of C57 BL/6 mice were assessed for long periods, from very early to late stages, after acute or chronic UVB irradiation. Acute UVB irradiation produced an increase in lipid peroxide levels that peaked 18 h after irradiation, after which the levels declined to a minimum 2–3 days after irradiation and then gradually rose to baseline. Chronic irradiation caused the lipid peroxide level to fall to a minimum at 0.5–1.0 weeks, after which it gradually returned to baseline by the third week. SOD and GSH-Px activities decreased sharply after acute irradiation, reaching a minimum 18 h after irradiation. Following chronic irradiation, these enzyme levels peaked after 0.5 weeks, and thereafter declined gradually to the original levels 3 weeks after irradiation. In contrast, catalase activity did not change significantly. Tanning began to increase at 1.5 weeks after irradiation, with an accelerated rate of increase from the third week. Although UVB has been reported only to decrease or impair reactive oxygen species (ROS) scavenging enzyme activity, we postulate the following from our results: (1) the increase in lipid peroxide levels observed after irradiation was due to UVB-induced ROS; (2) the parallel decrease in enzyme activities may have been due to inactivation by ROS; (3) the decrease in lipid peroxide levels following the peak at 18-h resulted from the scavenging effect of increasing SOD and GSH-Px activities, and (4) the increase in these two enzyme activities was the result of their induction by the increased lipid peroxides or ROS. In addition, these results seem to suggest a possible correlation of melanogenesis with UVB-induced ROS.

Multicentric reticulohistiocytosis in a child with sclerosing lesion of the leg: Immunohistopathologic studies and therapeutic trial with systemic cyclosporine

Multicentric reticulohistiocytosis affecting a 13-year-old boy induced a sclerosing change of the leg. The cellular infiltrate comprising activated T lymphocytes and macrophages and human lymphocyte antigen (HLA)-DR expression by keratinocytes in lesional skin all suggest the involvement of cellular immune reactions. We administered systemic cyclosporine but could not obtain a favorable effect without a concomitant low dosage of prednisone.

Neutrophil Chemotaxis, Phagocytosis, and Generation of Reactive Oxygen Species Show a Hierarchy of Responsiveness to Increasing Concentrations of N-Formyl-Met-Leu-Phe

We assessed the effect of varying concentrations of N-formyl-methionyl-leucyl-phenylalanine (fMLP) on neutrophil chemotaxis, phagocytosis, and reactive oxygen species generation. Boyden chamber chemotaxis was first elicited at an fMLP concentration of 10(-11) M, reached a peak at 10(-10) M, and declined at higher concentrations. Phagocytosis was first activated at 10(-10) M, reached its highest level at 10(-9) M, and declined at higher concentrations. O2-, H2O2 and OH. generation were elicited to a significant degree only at a fMLP concentration of 10(-8) M, or higher, reaching a peak at 10(-6) M. Thus, a distinct hierarchy was observed in the order of activation of these three neutrophil functions to varying concentrations of a soluble agonist. A teleologic model of neutrophil function that accounts for these observations is proposed.

Tuberculosis verrucosa cutis in a tumour-like form

An unusual case of tuberculosis verrucosa cutis that presented with a tumour‐like lesion on the heel is described. This responded rapidly to treatment with isoniazid.

Electromagnetic wave emitting products and “Kikoh” potentiate human leukocyte functions

Tourmaline (electric stone, a type of granite stone), common granite stone, ceramic disks, hot spring water and human palmar energy (called “Kikoh” in Japan and China), all which emit electromagnetic radiation in the far infrared region (wavelength 4–14 µm). These materials were thus examined for effects on human leukocyte activity and on lipid peroxidation of unsaturated fatty acids. It was revealed that these materials significantly increased intracellular calcium ion concentration, phagocytosis, and generation of reactive oxygen species in neutrophils, and the blastogenetic response of lymphocytes to mitogens. Chemotactic activity by neutrophils was also enhanced by exposure to tourmaline and the palm of “Kikohshi” i.e., a person who heals professionally by the laying on of hands. Despite the increase in reactive oxygen species generated by neutrophils, lipid peroxidation from unsaturated fatty acid was markedly inhibited by these four materials. The results suggest that materials emitting electromagnetic radiation in the far infrared range, which are widely used in Japan for cosmetic, therapeutic, and preservative purposes, appear capable of potentiating leukocyte functions without promoting oxidative injury.

Lucigenin-dependent chemiluminescence in neutrophils stimulated with stratum corneum sheet

It is known that a direct exposure of the stratum corneum (SC) to living tissues induces intense inflammatory changes [2]. Moreover, there are several dermatoses characterized by sterile pustule formation at the subcorneal locations, in which we frequently find C3 deposition at the SC [1, 3] that is densely attacked by neutrophils. We have found through in vitro experiments that both human SC homogenates [10] and the insoluble contents of epidermal cysts [11] activate the alternative complement pathway to produce leukocyte chemotactic C5a anaphylatoxin. In this paper, we present evidence that a direct interaction of neutrophils with SC in the presence of plasma or preopsonized generated reactive oxygen species assessed by lucigenin-dependent chemiluminescence (eL). The CL assay using isolated neutrophils is a simple and rapid method for monitoring the respiratory burst of neutrophils. However, CL responses assayed in isolated neutrophils frequently suffer from much variation. On the other hand, better reproducibility as well as no spontaneous responses are obtained by CL assay with whole blood [6] with similar levels of peak intensity when measured within 4 h after preparation [7]. In our preliminary study we found that SC-induced CL noted in whole blood, however, was too low to detect. Therefore, in this study we used a neutrophil suspension supplemented with 50 times diluted sediment of erythrocytes, which resulted in a good reproducibility as well as a decreased spontaneous CL response. A sheet of the normal human SC was obtained by stripping with adhesive cellophane tape 5 cm in width (Nichiban, Tokyo), from the flexor surface of the forearm of healthy individuals. After removing overlying SC

Lucigenin-Induced Chemiluminescence in Human Neutrophils in the Process of Chemotactic Migration Measured in a Modified Boyden Chamber

To the question of whether an oxidative metabolism of neutrophils occurs in the process of chemotactic migration, we have already demonstrated that formyl-peptide and zymosan-activated serum effectively induced lucigenin-dependent chemiluminescence (CL) in a specially devised Boyden chamber. In the present study we confirmed this and, furthermore, demonstrated that superoxide dismutase partially suppressed the neutrophil chemotaxis to formyl-peptide and concanavalin A, suggesting the participation of superoxide in a chemotactically migrating mechanism. However, monocyte-derived chemotactic factor did not cause any light emission, irrespective of its chemotactic activity. Based on these results, neutrophil chemotactic factors seem to be divided into two types, that is, oxidative metabolism-related and nonrelated. To the former group of chemotactic factors a premature activation of oxidative metabolism in neutrophils may start even at the initial stage of chemotaxis, and these primed cells may respond with a respiratory burst to higher concentrations of the chemoattractant itself or to other chemical mediators present at the site of inflammation.

Interaction between human neutrophils and corneocytes: corneocyte-induced respiratory burst of neutrophils assessed by chemiluminescence.

In an in vitro study to examine whether corneocytes stimulate neutrophils to cause a respiratory burst, we found that stratum corneum (SC) homogenates obtained from the sole of healthy individuals induced a substantial respiratory burst in human neutrophils when assessed by lucigenin-dependent chemiluminescence (CL) in the presence of the fresh human serum. Electron microscopically, the interaction between corneocytes and neutrophils was shown as distinctive deformation of the neutrophils adhering to the surface of the corneocytes that suggested a specific binding between SC and neutrophils. In contrast, in the heat-inactivated serum-supplemented system, the peak intensity of SC-induced CL was significantly decreased, being only slightly higher than that noted in the SC-free background. To circumvent the time-consuming preparation of the SC homogenates, we measured CL with a sheet of SC obtained by stripping with adhesive cellophane tape. In this case we used plasma because the complement was easily activated by cellophane tape itself when serum was used. To evaluate the influence of the location of horny tissue in the SC on CL in neutrophils, we used SC sheets stripped with cellophane tape from various levels of the SC. However, there was no significant difference in CL responses between SC sheets obtained by 1, 2, 3, 5, 10, or 15 strippings. Our findings suggest that when SC comes in contact with serum, it is opsonized by C3b, and such SC causes a respiratory burst of neutrophils following their specific binding on the surface of corneocytes.

Enhancing effect of protein A on the interaction between opsonized corneocytes and neutrophils in Staphylococcal infection

Abstract Formation of subcorneal pustules characterizes skin lesions infected by Staphyloeoccus aureus. To elucidate the mechanism underlying the subcorneal pustule formation as well as that of anti‐bacterial host defence, we studied the effect of Staphylococcal protein A on the interaction between the stratum corneum (SC) and neutrophils. We found that protein A significantly promoted opsonized SC‐induced chemiluminescence (CL) in neulrophils. This was specific to SC because no enhancement was observed with opsonized zymosan. It look place even with the serum obtained from a patient with agammaglobulinemia, ruling out the possibility of the involvement of Fc‐receptors of neutrophils in this phenomenon. Microscopic observation of such SC revealed an increase in the number of neutrophils adhering to the surface of the protein A‐coated corneocytes. Ultrastructural observation showed a distinct deformation of the neutrophils adhering to the surface of thc corneocytes, suggesting that they are in an activated stale. Such an enhanced interaction between protein A‐attached SC and neutrophils seems lo play an important role in the host defence mechanism against the invading S. aureus and in the production of the characteristic pustules by the neutrophil‐mediated damage of the surrounding epidermal tissue.

M2-Polarized Macrophages Compose Lupus Vulgaris Arising from a Bacillus Calmette-Guérin Vaccination Site

Since bacillus Calmette-Guérin (BCG) is an attenuated strain of Mycobacterium bovis, lupus vulgaris (LV) is reported as one of the rare complications after BCG vaccination, correlating with immunosuppression in the lesional skin. In this report, we describe a case of LV arising from the BCG vaccination site 22 years after vaccination. Interestingly, in the present case, granuloma cells were composed of M2-polarized macrophages. Our case might explain the contribution of M2-polarized macrophages to the biology of LV arising from a BCG vaccination site.