The aim of this study was to explore the usefulness of a human monocyte cell line in the development of in vitro models for predictive testing of contact sensitizers. Several studies have shown that contact sensitizers induce CD86 expression and enhanced internalization of MHC class II molecules in dendritic cells (DCs). We used THP-1, a human monocyte cell line, as a replacement for DCs for evaluation of these phenotypical alterations as predictive endpoints for contact sensitizers. Known sensitizers and irritants were evaluated. After 24-h exposure to samples, the expression of CD86 on THP-1 cells was measured by flow cytometry. Sensitizers such as dinitrochlorobenzene (DNCB), 2-mercaptobenzothiazole (MBT), eugenol, p-phenylenediamine (PPDA) and ammonium tetrachloroplatinate (Pt) enhanced CD86 expression on THP-1 cells, while nickel sulfate, cobalt sulfate and irritants such as methylsalicylate (MS), sodium dodecyl sulfate (SDS) and dimethyl sulfoxide (DMSO) did not augment CD86 expression. A synergistic effect was observed when DNCB and IFN-alpha were added simultaneously to a culture of THP-1 cells. Furthermore, internalization of MHC class II molecules was observed when the cells were treated with some of sensitizers for 2 h. The inducing effects of chemicals on the two phenotypical alterations were the same. These results suggest that these test systems can be used to predict contact-sensitizing ability of chemicals as an in vitro sensitization assay.

Animal Testing Alternatives↗

PubMed2002

Butyl benzyl phthalate, an endocrine disrupter, inhibits pulsatile luteinizing hormone secretion under an insulin-induced hypoglycaemic state in ovariectomized rats.

Butyl benzyl phthalate (BBP) and bisphenol A (BPA), termed endocrine disrupters, are known to mimic oestrogen in their actions, and therefore there is concern about their effect on reproductive functions. Since it is reported that the inhibitory action of oestrogen on the pulsatile secretion of luteinizing hormone (LH) is enhanced under insulin-induced hypoglycaemia, whether this also applies to BBP and BPA was examined in the present study. In adult ovariectomized (OVX) rats, the pulsatile LH secretion 24 h after subcutaneous injection of 10 mg BBP (BBP-treated), 10 mg BPA (BPA-treated) or 100 ng 17beta-oestradiol (E2-treated), all of which were dissolved in sesame oil, was not changed significantly compared to that after the injection of sesame oil only. Furthermore, in oil-treated OVX rats, the pulsatile LH secretion immediately after intravenous injection of insulin (1.0 U) was not changed compared to that after saline injection. In BBP-treated OVX rats, the injection of insulin (1.0 U) significantly decreased the number of LH pulses as in E2-treated OVX rats. The injection of insulin did not significantly affect the amplitude of LH pulses in BBP-, BPA- and E2-treated OVX rats. The results indicate that the oestrogenic action of BBP is significantly enhanced by insulin-induced hypoglycaemia and thus the pulsatile LH secretion is inhibited. We suggest that weak oestrogenic endocrine disrupters may become harmful to reproductive functions even in adult female rats, if acting under a low energy state.

Animals↗

PubMed2001

Thermolysin improves mutation analysis in skin epidermis from ultraviolet light-irradiated Muta Mouse.

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Animals↗

PubMed2001

Efficacy of early piston-type high-frequency oscillatory ventilation in infants with respiratory distress syndrome.

We investigated whether the combination of surfactant replacement therapy and early application of high-frequency oscillatory ventilation (HFOV) was more effective in patients with respiratory distress syndrome (RDS) than late application of HFOV and conventional mechanical ventilation (CMV). To determine this, we retrospectively reviewed the cases of 126 neonates with RDS who received surfactant replacement therapy within 4 hr after birth. Patients were grouped into those who received HFOV immediately after birth (HFOV group), those who initially were ventilated by CMV and subsequently received HFOV (CMV/HFOV group), and those who did not receive HFOV (CMV group). Changes in respiratory system compliance (Crs), arterial-alveolar oxygen gradient (a/ApO(2)), and mean airway pressure (MAP) were compared. Infants who received HFOV were less mature than those who received CMV. The a/ApO(2) measured immediately after birth before surfactant replacement therapy was significantly lower in the HFOV and CMV/HFOV group than in the CMV group. After 72 hr, the Crs in the HFOV group was higher than in any other group and was significantly higher than the CMV/HFOV group at 48 and 120 hr. These results suggest that initiating HFOV in combination with surfactant replacement therapy immediately after birth provides effective ventilatory support for infants with RDS.

Equipment Design↗

PubMed2001

Proliferative activity of CD8(+) T cells as an important clue to analyze T cell-mediated inflammatory dermatoses.

To elucidate the pathogenesis of T cell-mediated inflammatory skin diseases, we examined the exact sites where CD8(+) T cells proliferate, correlating them with the localization of antigen-presenting dendritic cells. We performed CD8/Ki-67 double immunohistochemical staining and single staining for CD1a, CD68, and factor XIIIa on sections of paraffin-embedded tissue samples of inflammatory dermatoses in which T lymphocytes are thought to play a crucial role. The dermatoses were lichen planus (12 samples), acute graft-versus host disease (GVHD) (12 samples), chronic GVHD (10 samples), spongiotic dermatitis (8 samples) and psoriasis (7 samples). Labelling for Ki-67 among CD8(+) T cells was predominantly observed in the subepidermal lymphoid infiltrate, and was scanty in the epidermis. This suggested that proliferation of CD8(+) T cells occurred preferentially in the dermis. The labelling index for Ki-67 among dermal and epidermal CD8(+) cells was quite different among the different diseases studied (P < 0.05). They were rich in the subepidermal portion of the dermis of spongiotic dermatitis, acute GVHD and chronic GVHD, but rare in the dermis of psoriasis and lichen planus. A moderate infiltrate was also observed in lesional epidermis of spongiotic dermatitis, acute GVHD and chronic GVHD, whereas they was almost none in the epidermis of psoriasis and lichen planus. CD1a(+) dermal dendritic cells were densely distributed within the lymphoid infiltrate in the affected dermis of spongiotic dermatitis, psoriasis and lichen planus, whereas they were minimal in GVHD. These dermal dendritic cells are candidates as stimulators on T cells in the dermis. In conclusion, the proliferative status of T cells could be an important clue in the elucidation of the pathophysiology of T cell-mediated inflammatory dermatoses.

Acute Disease↗

PubMed2001

Normal proliferative responses of peripheral blood mononuclear cells to streptococcal preparation OK-432 in patients with pustulosis palmaris et plantaris constitute a distinct feature from the reduced responses observed in those with psoriasis vulgaris, pustular psoriasis, and acrodermatitis continua of Hallopeau.

It was previously reported that peripheral blood mononuclear cells (PBMC) from the patients with psoriasis vulgaris (PV) showed a reduced proliferative response in vitro to the stimulation of a lyophilized preparation of penicillin-treated low virulence Su-strain of Streptococcus pyogenes group 3, OK-432. In this study, at first it was examined whether OK-432 acts as a superantigen. By analyzing the usage of Vbeta T-cell receptor (TCR) of proliferating T cells stimulated with OK-432, it was found that OK-432 stimulated preferentially Vbeta2 TCR-bearing T cells. Next, to find differences in in vitro responses of PBMC among various types of sterile pustular dermatoses such as pustulosis palmaris et plantaris (PPP), acrodermatitis continua of Hallopeau (AC), and generalized pustular psoriasis (GPP), the proliferative responses of PBMC obtained from these patients under the stimulation of OK-432 were compared. When the PBMC was stimulated with interleukin (IL)-2, no significant difference was found in their proliferative responses among those obtained from the patients with these sterile pustular dermatoses, PV or healthy controls. However, like those from PV patients, PBMC from AC and GPP patients showed significantly smaller responses to OK-432 than those from the healthy controls. In contrast, the proliferative responses of PBMC from the patients with PPP to OK-432 was comparable to those from healthy controls. These results, in addition to its unique clinical and histopathological characteristics, suggest that PPP has a different pathogenetic background from that underlying PV, AC, or GPP.

Acrodermatitis↗

PubMed2001

Cytokine mRNA profiles in cultured human skin component cells exposed to various chemicals: a simulation model of epicutaneous stimuli induced by skin barrier perturbation in comparison with that due to exposure to haptens or irritant.

The skin protects our body by producing an efficient barrier membrane, the stratum corneum, from desiccation as well as from various damaging effects of environmental chemicals. Although the skin expresses various cytokines after barrier perturbation, exact cell types producing each cytokine have not been determined. Using a cell culture system, we analyzed the initial responses of various cutaneous cells to treatments simulating epicutaneous stimuli induced by a barrier perturbation of the skin in comparison with those caused by irritant or hapten exposure. We used cultured normal human epidermal keratinocytes (NHEK), human microvascular endothelial cells (HMVEC) and normal human dermal fibroblasts (NHDF). We treated them with the following chemicals and examined their cytokine mRNA levels 6 h later: high osmotic (0.5 molar) NaCl and hydrogen peroxide (H2O2), which simulate desiccation and exposure to high oxygen pressure, respectively, that may take place in vivo after perturbation of the barrier. In addition, we also studied their response to two representive haptens, nickel chloride (NiCl2) and dinitrochlorobenzene (DNCB), and an irritant, sodium dodecyl sulfate (SDS). We found that 0.5 M NaCl treatment increased mRNA levels of proinflammatory cytokines such as IL-1alpha, IL-6 and IL-8 as well as ICAM-1 in NHEK and IL-1alpha, IL-1beta and IL-6 mRNA levels in NHDF. In contrast, H2O2 treatment remarkably increased IL-10, GMCSF and ICAM-1 mRNA levels in NHEK, and IL-6 mRNA levels in HMVEC and NHDF. The exposure to haptens did not induce any remarkable increase in mRNA levels of the proinflammatory cytokines in NHEK. But NiCl2 increased IL-1alpha, IL-6 and IL-8 mRNA levels in HMVEC, while DNCB increased only their IL-6 mRNA levels. By contrast, SDS stimulated all the cell types to increase at least some of these proinflammatory cytokine mRNA levels. Our present data suggest that each skin component cell participates in inflammatory processes of the skin through its distinctive cytokine production profile when the skin barrier is compromized physically or chemically.

Cells, Cultured↗

PubMed2001

Human follicular papilla cells carry out nonadipose tissue production of leptin.

Leptin, a satiety-regulating cytokine, is predominantly expressed by adipocytes, although recently the nonadipose tissue production of leptin has been reported. To investigate the possibility of leptin production by human scalp hair follicles, we examined leptin production and its mRNA expression by cultured human follicular papilla cells. We isolated 12 human follicular papilla cell lines from different individuals. They were identified by their morphology, their high alpha-smooth-muscle actin expression, their inability to differentiate into adipocytes, and by the lack of mRNA for adipose-specific fatty acid binding protein. All the human follicular papilla cell lines, but not neonatal human dermal fibroblasts, produced significant amounts of leptin demonstrable by enzyme-linked immunosorbent assay. We demonstrated leptin mRNA expression by human follicular papilla cell lines, but not by neonatal human dermal fibroblasts, by reverse transcription polymerase chain reaction. By immunohistochemistry and in situ hybridization, we detected both leptin protein and mRNA at the lower portion of the hair follicle, i.e., hair matrix, inner root sheath of the hair bulb, and human follicular papilla cells. In contrast, the leptin receptor with intracytoplasmic signal sequence was detected in the follicular papilla cells immunohistochemically, and the long isoform of the leptin receptor mRNA was demonstrated in the human follicular papilla cell lines by reverse transcription polymerase chain reaction. Finally, by using these human follicular papilla cell lines, we showed that cytokines such as interleukin-1 beta, tumor necrosis factor alpha, interferon-gamma, and interleukin-4, and growth factors such as epidermal growth factor, basic fibroblast growth factor, and transforming growth factor beta1, but not vascular endothelial growth factor, hepatocyte growth factor, keratinocyte growth factor, and insulin-like growth factor 1, significantly downregulated the production of leptin. These data demonstrated that human follicular papilla cells produce leptin and express the functional leptin receptor in vivo and in vitro, suggesting its autocrine function. Moreover, the regulation pattern of its production by various factors suggests a pivotal role of leptin in hair biology.

Adipocytes↗

PubMed2001

Increased urinary leukotriene E4 excretion in patients with atopic dermatitis.

BACKGROUND: Synthesis of cysteinyl leukotrienes (LTs) is known to play a part in the pathogenesis of inflammatory diseases. OBJECTIVES: To define the involvement of cysteinyl LTs in atopic dermatitis (AD). METHODS: Synthesis of cysteinyl LTs was assessed in patients with AD and healthy volunteers by measuring urinary LTE4, a useful index of systemic cysteinyl LT synthesis, using liquid chromatography/tandem mass spectrometry. RESULTS: Mean +/- SD urinary LTE4 levels in patients with AD (125 +/- 69 pg mg(-1) creatinine, n = 20) were significantly higher (P < 0.01) than in healthy volunteers (60 +/- 19 pg mg(-1) creatinine, n = 17). A significant correlation between urinary LTE4 and total serum IgE levels in patients with AD was observed (r = 0.643, P < 0.05). CONCLUSIONS: Our findings demonstrate an enhanced synthesis of cysteinyl LTs in patients with AD and suggest that cysteinyl LTs are involved in the pathophysiology of AD.

Adolescent↗

PubMed2001

Acral angiokeratoma-like pseudolymphoma: one adolescent and two adults.

In 1988, Ramsay et al proposed an entity of acral pseudolymphomatous angiokeratoma of children (with an abbreviation of APACHE) for the unilateral multiple angiomatous papules affecting the acral region of the extremities of children. We report here similar lesions that developed in the acral portions of 1 female adolescent and 2 women. Histopathologically, they showed pseudolymphomatous features rather than those of angiokeratoma. Thus, the term should be acral angiokeratoma-like pseudolymphoma would be more appropriate than APACHE originally proposed.

Adult↗

PubMed2001

Erythematous swelling of the lip associated with Sjögren's syndrome and mimicking cheilitis granulomatosa.

A 64-year-old Japanese woman developed therapy-resistant erythematous swelling of her upper lip. Our tentative clinical diagnosis of cheilitis granulomatosa was ruled out later by the laboratory findings including increased levels of anti-nuclear-antibody (ANA), anti-SSA/Ro antibody, and positive Schirmer test as well as by a histopathological picture showing a dense perivascular infiltration of plasma cells and mononuclear cells in the dermis instead of granulomatous changes. To the best of our knowledge, this is the first patient in whom annular erythema associated with S ogren's syndrome involved only the upper lip and produced clinical features simulating cheilitis granulomatosa.

Diagnosis, Differential↗

PubMed2000

Kinetics of product inhibition in alcohol fermentation. Reprinted from Biotechnology and Bioengineering, Vol. X, Issue 6, Pages 845-864 (1968).

The inhibitory effect of ethanol concentration p in a medium on the specific rates of growth mu and ethanol production nu of a specific strain of baker's yeast was studied in a chemostat, where except for ethanol as the product, only the concentration of glucose S was controlled to limit the metabolic activity of the yeast. This was designed to supplement the previous findings from the batch experiment, in which ethanol was added artificially and no substrate components were limiting the metabolism of the same yeast, that mu = mu(0)e(-k(1)p) and nu = nu(0)e(-k(1)p), where k(1) and k(2) are empirical constants and subscript the 0 denotes respective values at p = 0. The effects of p on the values of mu and nu were confirmed by the Line-weaver-Burk plot to belong to noncompetitive inhibition. The formulas here for mu and nu as affected by p, if extrapolated to the case of no limiting substrates, were in good agreement in respective forms with those derived previously from the batch experiment, though the values of corresponding coefficients in these formulas were different. The differential equations for mu and nu as functions of both p and S and, in addition for the rate of glucose consumption as correlated by the yield factors either with the cell growth rate or the rate of ethanol production, were solved properly with a digital computer. A kinetic pattern calculated so far was discussed with reference to the data obtained in the batch experiment and those relevant to actual "sake" brewing.

Culture Media↗

PubMed2000

In vitro treatment of human transforming growth factor-beta1-treated monocyte-derived dendritic cells with haptens can induce the phenotypic and functional changes similar to epidermal Langerhans cells in the initiation phase of allergic contact sensitivity reaction.

Human monocyte-derived dendritic cells (MoDCs) obtained from peripheral blood monocytes (PBMC) cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) can be activated in vitro by a variety of simple chemicals such as haptens and several metals. Recently, it has been demonstrated that transforming growth factor-beta1 (TGF-beta1) can induce further differentiation of MoDCs to the cells that share some characteristics with epidermal Langerhans cells, i.e. they contain Birbeck granules and express E-cadherin. In this study, using such TGF-beta1-treated dendritic cells (TGF-beta1+ DCs), we examined the in vitro effects of representative haptens, i.e. NiCl2 and dinitrochlorobenzene (DNCB), on their phenotypic and functional characteristics, comparing with those reported in vivo in epidermal Langerhans cells during the sensitization phase of a contact sensitivity reaction. Treatment of TGF-beta1+ DCs with NiCl2 increased their expression of the molecules related to antigen presentation such as CD86, major histocompatibility complex class I and class II, and CD83, although weakly, in addition to that of those essential for their migration to the regional lymph nodes, such as CD49e, CD44 and its variant 6, while it down-regulated the expression of the molecules required for homing to the skin and staying in the epidermis, such as cutaneous leucocyte antigen (CLA) and E-cadherin. It also increased the production of tumour necrosis factor-alpha, but not that of IL-1beta or IL-12. DNCB also increased their CD86 expression and down-regulated E-cadherin and CLA, but did not affect other phenotypic changes that were observed in TGF-beta1+ DCs treated with NiCl2. TGF-beta1+ DCs treated with either NiCl2 or DNCB increased their allogeneic T-cell stimulatory function. In addition, reverse transcribed polymerase chain reaction revealed augmented expression of chemokine receptor 7 mRNA by TGF-beta1+ DCs when treated with either NiCl2 or DNCB. Moreover, consistent with this data, TGF-beta1+ DCs treated with these chemicals chemotactically responded to macrophage inflammatory protein-3beta. These data suggest the possibility that TGF-beta1+ DCs present a good in vitro model to study the biology of epidermal Langerhans cells.

Antigens, Differentiation, T-Lymphocyte↗

PubMed2000

Dermatofibroma with diffuse eosinophilic infiltrate.

Dermatofibroma, a common form of benign fibrous histiocytoma, is characterized by the presence of different cell types consisting of fibroblastic, histiocytic, and even multinucleated cells. Dermatofibromas are always accompanied by an inflammatory lymphoid cell reaction, including B cells and T cells at their border. To our knowledge, however, there is no report of an infiltration of eosinophils within this tumor. We describe a dermatofibroma on the pretibial region of an 8-year-old boy. Microscopic examination revealed a diffuse eosinophilic infiltration within the dermatofibroma, which was typically composed of histiocytic cells and mature collagen. The diagnosis of dermatofibroma was confirmed by demonstrating the immunoreactivity of tumor cells to an anti-factor XIIIa antibody.

Child↗