Evaluation of skin perfusion pressure to assess refractory foot ulcers.

OBJECTIVE: The number of patients with foot gangrene caused by critical ischaemia and severe infection is increasing significantly in developed countries. The measurement of perilesional skin blood flow by skin perfusion pressure (SPP) is useful to select the appropriate treatment of gangrenous lesions, in that it is not affected by calcifications of blood vessels. However, the prognosis of a foot ulcer may also be affected by the level of blood sugar and infections. This study aimed to validate the use of SPP in cases of foot gangrene and ulcers in patients with and without diabetes mellitus (DM) and infection. METHOD: Clinical symptoms, ankle-brachial pressure index (ABPI) and SPP were assessed to evaluate the condition of each foot ulcer. Every foot ulcer was treated as independent, even if a participant had multiple ulcers. All ulcers for which we measured SPP were subject to the analysis. All ulcers were purely ischaemic in nature and were exclusively located on the foot or toes. RESULTS: Data were collected from 117 foot ulcers on 91 toes and feet from 65 patients. Almost all SPP values in healed cases were > 27 mmHg. There were three patients whose ulcers failed to heal by conservative treatments were complicated with severe infection. However, no effect of DM on the relationship between SPP values and prognosis was observed. Logistic regression analysis of all ulcers except for the 5 cases complicated with infection revealed that those with 30 mmHg or lower SPP values are likely to heal by conservative treatment with 23% or lower probability, whereas any ulcer with more than 50 mmHg SPP value and without severe infection may heal without the need for further operations with 80% or higher probability. CONCLUSION: The combination of SPP and careful evaluation of infection may be a good parameter to decide the appropriate treatment for ischaemic skin ulcers, regardless of the complication of DM.

Prognosis of chronic spontaneous urticaria in 117 patients not controlled by a standard dose of antihistamine.

BACKGROUND: Chronic spontaneous urticaria (CSU) is a common skin disorder, but its clinical course reported so far is largely variable, probably due to the heterogeneity of the clinical background of patients and pathogenesis of this disease. METHODS: To reveal the prognosis of refractory CSU, we retrospectively studied the patients who suffered from spontaneous urticaria for six weeks or longer at their first visit to our outpatient clinic, who were insufficiently controlled by a standard dose of antihistamine, and revisited from 2003 to 2009. RESULTS: Among 223 patients with CSU, 117 patients fulfilled the criteria mentioned above. Mean disease duration at first visit and mean duration of follow-up at our hospital were 27.4 ± 4.2 months and 18.7 ± 1.9 months, respectively. By using Kaplan-Meier methods, the estimated improved rates at 12 months, 24 months, and 60 months were 36.6%, 51.2%, and 66.1%, respectively. The overall improvement rate of childhood cases (<19 years) was significantly higher than that of adult cases (P = 0.007, log-rank test). Moreover, the improvement rate of patients with short disease durations (<1 year at the first visit) was significantly (P = 0.003, log-rank test) higher than that of patients with long disease durations (one year or more). CONCLUSION: Our data indicate that the condition of patients with CSU can be gradually improved even in intractable cases. Information about the clinical course and prognostic factors of CSU in this study could help physicians predict the prognosis of patients and ensure medication adherence of patients with CSU.

Cellulose sulfate suppresses immunoglobulin E production by murine B lymphocytes in vitro.

BACKGROUND: Immunoglobulin (Ig) E plays an important role in the pathogenesis of allergic diseases such as atopic dermatitis and allergic asthma.We previously reported that a sulfate polysaccharide, fucoidan, suppressed IgE production by murine B cells in vitro. However, the mechanism by which fucoidan suppresses IgE production remains unclear. OBJECTIVE: We incorporated sulfate groups into cellulose and studied their biological characteristics in vitro to explore the possibility of converting biologically neutral polysaccharides to active reagents with antiallergic functions. MATERIAL AND METHODS: Cellulose was chemically processed using N,N-dimethylformamide (DMF) and DMF-sulfurtrioxide and recovered as cellulose sulfate with a molecular weight of around 10 kDa. We then studied the effect of cellulose sulfate on IgE production from B cells, IgE class-switching, and populations of IgE-secreting B cells prepared from murine spleen. We also investigated the effects of sulfated cellulose on the production of interleukin (IL) 4 and interferon (IFN) gamma and the expression of T-bet mRNA by splenic T cells. The cytotoxicity of cellulose sulfate was also examined. RESULTS: Cellulose sulfate suppressed IgE production in B cells stimulated with IL-4 and anti-CD40 antibody by inhibiting IgE class-switch recombination and decreasing the number of IgE-secreting B cells in vitro. Moreover, both cellulose sulfate and fucoidan suppressed IL-4 production and enhanced IFN-gamma production by murine T cells stimulated with anti-CD3 and anti-CD28 antibodies, despite the decrease in T-bet mRNA expression. CONCLUSIONS: Cellulose gains an antiallergic effect on B cells and T cells with the addition of sulfate groups.

The IL-6 family cytokines, interleukin-6, interleukin-11, oncostatin M, and leukemia inhibitory factor, enhance mast cell growth through fibroblast-dependent pathway in mice.

Mast cell hyperplasia is observed in various inflammatory skin diseases. Although the mechanisms involved in the pathogenesis of these conditions remains largely uninvestigated, it is speculated that mediators produced in the lesional skin provide a favorable microenvironment for mast cell growth. Among the proinflammatory mediators, leukemia inhibitory factor (LIF), which shares a receptor component (gp130 subunit) with interleukin-6 (IL-6), has been identified as a mast cell growth-enhancing factor produced by cells of the keratinocyte-derived cell line (KCMH-1). In this study, we investigated the effect of four IL-6 family cytokines, IL-6, IL-11, oncostatin M (OSM) and LIF on mast cell growth in a mast cell/fibroblast co-culture system. When mouse bone marrow-derived cultured mast cells (BMMC) were maintained on a NIH/3T3 fibroblast monolayer, these cytokines induced proliferation of the mast cells, but none of the cytokines had any effect on mast cell proliferation in the absence of fibroblasts. mRNA for gp130 and receptors for the four IL-6 family cytokines were detected in NIH/3T3 fibroblasts by reverse transcriptase-mediated polymerase chain reaction. In contrast, only mRNA for the IL-11 receptor and gp130 were detected in BMMC. Tyrosine phosphorylation of gp130 was observed in NIH/3T3 fibroblasts after stimulation with all the cytokines. Some IL-6 family cytokines enhanced the production of stem cell factor (SCF), a potent mast cell growth factor, from NIH/3T3 fibroblasts, but the amount of SCF produced by NIH/3T3 fibroblasts was not paralleled by the mast cell growth-enhancement induced by the IL-6 family cytokines. When anti-SCF antibody was added with the IL-6 family cytokines in the BMMC/fibroblast coculture system, a significant effect of these cytokines remained, although the growth-enhancing activity was markedly reduced. A similar result was obtained when BMMC were prepared from W/W(V)-mice, which lack functional c-kit, in the BMMC/ fibroblast coculture system. These results suggest that IL-6 family cytokines stimulate mast cell growth by a fibroblast-dependent mechanism, and also suggest the existence of another pathway between BMMC and NIH/3T3 fibroblasts cooperating with the SCF/c-kit pathway. IL-6 family cytokines may thus contribute to mast cell hyperplasia in skin diseases.

Interleukin-1 alpha enhances mast cell growth by a fibroblast-dependent mechanism.

Mast cell hyperplasia is observed in various inflammatory skin diseases. Although the pathogenesis of these conditions remains largely uninvestigated, it has been speculated that lesional mediators provide a favorable microenvironment for mast cell growth. We investigated the effect of an inflammatory cytokine, IL-1 alpha, on mast cell growth in a mast cell/fibroblast coculture system. When mouse bone marrow-derived cultured mast cells (BMMC) were cultured on a NIH/3T3 fibroblast monolayer, IL-1 alpha stimulated mast cell proliferation. However, IL-1 alpha did not stimulate 3H-thymidine incorporation in BMMC in the absence of fibroblasts. Separation of BMMC from fibroblasts by a permeable micropore membrane reduced the effect of IL-1 alpha. When BMMC were prepared from W/Wv mice, which lack a functional c-kit, or when NIH/3T3 fibroblasts were substituted with Sl/Sld-derived fibroblasts, which lack membrane-bound stem cell factor (SCF), a lower, but significant, effect of IL-1 alpha was observed. Flow cytometric analysis revealed no enhancement of SCF expression on fibroblasts following stimulation with IL-1 alpha. Neutralizing antibodies against IL-3, IL-4, IL-10, and nerve growth factor (NGF) showed no inhibition. On the other hand, indomethacin inhibited the effect of IL-1 alpha, and prostaglandin E2 induced mast cell growth in the co-cultures. These results indicate that IL-1 alpha stimulates mast cell growth by a fibroblast-dependent mechanism, in which SCF/c-kit interaction may participate in a major way. The mast cell growth activity induced by this cytokine can, at least in part, be attributed to prostaglandins. Inflammatory cytokines may thus contribute to mast cell hyperplasia in skin diseases.

Altered in vitro apoptosis of cultured mast cells prepared from an inbred strain of mice, NC/Kuj.

BACKGROUND: An inbred strain of mice, NC, develops dermatitis associated with highly elevated serum IgE and dermal mast cell hyperplasia. OBJECTIVES AND METHODS: To clarify the mechanisms for the dermal mast cell hyperplasia in NC, we prepared bone marrow-derived mast cells (BMMCs) from three strains of mice, NC/Kuj, C57BL/6 and BALB/c, and compare histamine contents, histamine release abilities, adhesive properties and apoptosis of the BMMCs. RESULTS: Compared with BMMCs obtained from C57BL/6 and BALB/c, NC/Kuj BMMC possessed higher histamine content and higher adhesive ability to plastic plates, although histamine release from BMMCs was found to be similar in the three strains. The most intriguing finding is the lack of apoptosis in the BMMCs from NC/Kuj upon growth factor deprivation as determined by DNA ladder formation and loss of membrane phospholipid asymmetry. CONCLUSION: The altered in vitro properties of mast cells in NC/Kuj partially account for an increase of dermal mast cells, which might be involved in the development of skin lesions in NC.

Leukemia inhibitory factor enhances mast cell growth in a mast cell/fibroblast co-culture system through stat3 signaling pathway of fibroblasts.

Leukemia inhibitory factor (LIF) enhanced mast cell growth in a mast cell/3T3 fibroblast co-culture system, however the precise mechanisms have not been defined. Western blot analysis showed that bone marrow-derived mast cells failed to express both LIF receptor (LIFR) and gp130, whereas 3T3 fibroblasts expressed both LIFR and gp130. This result indicates that the activity of LIF for mast cell growth is mediated by 3T3 fibroblasts. Signal transducer and activator of transcription (Stat) 3-transfected 3T3 fibroblasts enhanced mast cell growth. In addition, dominant-negative Stat3-transfected fibroblasts blocked LIF-mediated mast cell growth in the co-culture system. In conclusion, LIF-induced mast cell growth in the co-culture system is mediated by an indirect pathway via 3T3 fibroblasts through activating Stat3 signaling pathway in 3T3 fibroblasts.

Fur mites induce dermatitis associated with IgE hyperproduction in an inbred strain of mice, NC/Kuj.

An inbred strain of mice, NC, has been introduced as an animal model for atopic dermatitis because the mice develop dermatitis associated with severe scratch preceded by elevated serum IgE level when kept in conventional conditions. Although hypersensitivity to some environmental factors is suggested to cause dermatitis, the precise factor remains unclear. As the mice maintained under conventional conditions were often infected with fur mites, we investigated whether an infection of fur mites induces skin lesions in NC. Infection with the fur mites induced NC to develop skin lesions associated with highly elevated serum IgE, whereas no obvious skin lesions were observed in BALB/c and C57BL/6, and the elevation of serum IgE level was minimal in these two strains of mice. The role of the fur mites in the manifestation of skin lesions and IgE hyperproduction was confirmed by eliminating the fur mites by treatment with ivermectin. In addition, the existence of specific IgE antibody to Myocoptes musculinus antigen in the sera of mite-infested NC was detected by the antigen-induced histamine release from bone marrow-derived cultured mast cells after sensitization with the serum. These results suggest that continuous exposure to fur mite antigen is a potential factor in the development of dermatitis in NC. We provide a new model system of antigen-induced dermatitis for investigating the role of IgE in eliciting dermatitis.

A fibrogenic cytokine, platelet-derived growth factor (PDGF), enhances mast cell growth indirectly via a SCF- and fibroblast-dependent pathway.

Mast cell hyperplasia is often observed in dermatoses characterized by fibrosis. Evidence has accumulated showing that a potent fibrogenic cytokine, platelet-derived growth factor (PDGF), plays a pathogenic role in dermal fibrosis. To clarify the mechanism of mast cell hyperplasia associated with fibrosis, we investigated the effect of PDGF on mast cell proliferation and the expression of stem cell factor (SCF), a potent growth factor for mast cells, in fibroblasts. When mouse bone marrow-derived mast cells (BMMC) were cultured on a NIH/3T3 fibroblast monolayer, mast cell proliferation was stimulated in both cell number and total histamine content by all isoforms of PDGF (-AA, -AB, and -BB); however, none of the isoforms had any effect on [3H] thymidine incorporation in BMMC in the absence of fibroblasts. The effect of PDGF-AB and -BB were abrogated either by the addition of anti-PDGF-AB antibody or by the separation of mast cells and fibroblasts by a permeable membrane filter with a pore size of 0.2 microm. Immunoblotting of the NIH/3T3 fibroblasts treated with PDGF revealed an enhanced expression of SCF in the membrane fraction and the effect of PDGF was neutralized by the addition of antibody against SCF. Moreover, no effect of PDGF was observed when BMMC were prepared from W/W(v) mice that lack functional c-kit as the SCF receptor or when 3T3 fibroblasts were prepared from Sl/Sl(d) mice that lack membrane-bound SCF. These results suggest that the fibrogenic cytokine PDGF stimulates mast cell hyperplasia via the expression of membrane-bound SCF by fibroblasts in association with fibrosis of the skin.

A novel point mutation in the steroid sulfatase gene in X-linked ichthyosis.

We analyzed the steroid sulfatase (STS) gene in nine Japanese patients with X-linked ichthyosis (XLI) by a polymerase chain reaction technique and subsequent DNA sequencing. Eight of nine patients showed complete deletion of the STS gene. In a patient of XLI exhibiting a normal amplifying pattern with predicted sizes of the STS gene, a novel mutation was found resulting in the appearance of a stop codon in exon 7 of the STS gene. This suggests that exon 7 or an area in its downstream region is important for STS activity.