Hsin-Su Yu

Transepidermal water loss, serum IgE and β-endorphin as important and independent biological markers for development of itch intensity in atopic dermatitis

Backgroundu2002 Although itch is the predominant symptom of atopic dermatitis (AD), it is poorly characterized and subjective. The objective assessment of itch intensity is important for treatment and follow‐up in patients with AD.

FK506 inhibits tumour necrosis factor-α secretion in human keratinocytes via regulation of nuclear factor-κB

Backgroundu2002 Tacrolimus (FK506) ointment has been used for treatment of inflammatory dermatoses with remarkable success. Our previous studies have indicated that direct modulation of tacrolimus on keratinocytes (KCs) may have an impact on its therapeutic effect. The use of monoclonal antibody specific for tumour necrosis factor (TNF)‐α has shown efficacy in treating both psoriasis and Crohn disease. Topical tacrolimus has also been shown to be effective for treating cutaneous manifestations of both diseases.

Anti-dsDNA antibody up-regulates interleukin 6, but not cyclooxygenase, gene expression in glomerular mesangial cells: a marker of immune-mediated renal damage?

Abstract:Objective and Design: To determine whether anti-double stranded DNA antibody (anti-dsDNA) can affect the synthesis of eicosanoids and cytokines in rat glomerular mesangial cells (RMC).¶Materials or Subjects: Glomerular mesangial cells were isolated and subcultured from Sprague-Dawley rats. Monoclonal anti-dsDNA (12B3 clone) was derived from autoimmune MRL-lpr/lpr mouse by hybridoma technology.¶Methods: The mRNA expression of cyclo-oxygenase type 1 (COX-1), type 2 (COX-2), Th1 (IL-2 and IFN-γ)/Th2 (IL-4 and IL-10) and proinflammatory (IL-6 and TNF-α) and anti-inflammatory (TGF-β) cytokines of RMC ± anti-dsDNA was detected by RT-PCR. The PGE2 production by RMC ± anti-dsDNA was measured by ELISA. The statistical significance was assessed by non-parametric Wilcoxon signed rank test.¶Results: We found RMC spontaneously expressed COX-1, but not COX-2. The incubation of RMC with anti-dsDNA (50ng/ml) did not affect COX expression and PGE2 production by RMC. RMC also spontaneously expressed IL-6, TNF-α and TGF-β mRNA. However, only IL-6 was up-regulated by anti-dsDNA.¶Conclusions: Increased IL-6 expression in RMC may become a marker of anti-dsDNA-mediated immune damage of mesangial cells.¶

Interleukin-13 increases prostaglandin E2 (PGE2) production by normal human polymorphonuclear neutrophils by enhancing cyclooxygenase 2 (COX-2) gene expression

Objective: To investigate whether interleukin-13 (IL-13) can affect arachidonic acid metabolism and phagocytic activity of normal human polymorphonuclear neutrophils (PMN).¶Methods: Normal human PMN (1u2009×u2009106u2009cells/ml) were incubated with different concentrations of IL-13 (0.1–10u2009ng/ml) for a variety of times (30–120u2009min). Phagocytosis and intracellular cyclooxygenase-2 (COX-2) were detected by flow cytometry. The expression of COX-1 and COX-2 mRNA was detected by RT-PCR. The concentration of PGE2 in the PMN cultured supernatants was determined by EIA.¶Results: We found that IL-13 at an optimal concentration of 1u2009ng/ml significantly enhanced COX-2 gene expression and PGE2 production (121.57u2009±u200922.17u2009pg/ml in IL-13 stimulation vs. 73.16u2009±u200911.72u2009pg/ml in controls) by PMN. In addition, IL-13 stimulated PMN phagocytosis via increased complement receptor type 1 (CR1) and type 3 (CR3), but not IgG Fcγ receptor type 3 (FcγRIII). The cytoplasmic neutral esterase activity of PMN was also enhanced by IL-13 stimulation for 24u2009h.¶Conclusions: These results suggest that IL-13 can stimulate PMN and modulates the inflammatory reactions via the cyclooxygenase pathway.

Release of surface-expressed lactoferrin from polymorphonuclear neutrophils after contact with CD4+T cells and its modulation on Th1/Th2 cytokine production

It is conceivable that a membrane component(s) is transferred from antigen‐presenting cells to T cells after antigenic stimulation. However, it is not clear whether a certain membrane component(s) is transferred from polymorphonuclear neturophils (PMN) to T cells for immunomodulation. In the presence study, we cocultured two of the three autologous cells—PMN, CD4+T, and red blood cells (RBC)—homotypically or heterotypically for 1 h. Spontaneous membrane exchange between autologous PMN‐PMN and PMN‐CD4+T but not between CD4+T‐CD4+T or RBC‐CD4+T was observed with a confocal microscope. Loss of membrane exchange between two paraformaldehyde‐fixed cells suggests that mutual membrane exchange is via cell–cell contact. Different combinations of cellular enzyme‐linked immunosorbent assay for measuring the binding between fixed cells and biotinylated cell lysates showed the same tendency. To identify the molecule(s) mediating PMN‐CD4+T binding, we compared the banding of biotinylated PMN lysates and the banding of plain PMN lysate probed by biotinylated CD4+T lysate in 10% sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. We found that a 75‐ to 80‐kDa surface‐expressed molecule on PMN exists constantly to mediate PMN‐CD4+T binding. Peptide analysis disclosed that the molecule had 99.8% identity with lactoferrin (LF). The expression of LF on system lupus erythematosis (SLE)‐PMN is less than normal PMN. PMN‐CD4+T coculture increased LF expression on CD4+T. Normal PMN and human milk‐derived LF suppressed interferon‐γ (IFN‐γ) but enhanced interleukin (IL)‐10 production of anti‐CD3+anti‐CD28‐activated, normal CD4+T. In contrast, coculture of SLE‐PMN and autologous CD4+T suppressed IFN‐γ and IL‐10 production. These results suggest that the surface‐expressed LF released from PMN after contact with autologous CD4+T modulated its T helper cell type 1 (Th1)/Th2 cytokine production. Decreased LF expression on SLE‐PMN abnormally modulates Th1/Th2 production by CD4+T cells.

Interleukin 8 modulates interleukin-1β, interleukin-6 and tumor necrosis factor-α release from normal human mononuclear cells

Abstract Recombinant human interleukin 8 (IL-8) enhanced the release of inflammatory cytokines including interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) from normal human mononuclear cells in a dose-related manner (from 1 ng/ml to 10 ng/ml with a maximal effect at 5 ng/ml( when the cells incubated with IL-8 for 24 h. This cytokine-releasing activity of IL-8 is temperature-dependent and required protein synthesis since low temperature (4°C) and cycloheximide (100 μg/ml) minimized the cytokine release from MNC. However, when IL-8 concentration was greater than 20 ng/ml, the cytokine release was supressed. For further investigating the subcellular mechanism of the adverse effect of high dose IL-8 (20 ng/ml) in cytokine synthesis, human mononuclear cells (1 × 106/ml) were stimulated with PHA (1 μg/ml) in the presence of 20 ng/ml IL-8 for 3 days. We found not only [3H]thymidine incorporation of MNC was tremendously inhibited but DNA fragmentation appeared. Subsequently, the cell cycle of PHA-stimulated MNC retarded in the phase of G0/G1. These results suggest that in low concentration (5–10 ng/ml) IL-8 not only activated neutrophil phagocytosis but facilitated the release of inflammatory cytokines from mononuclear cells. Higher dose of IL-8 (more than 20 ng/ml) conversely suppressed these cytokine release from damaged cells by its cytotoxic effect. This newly found cytokine-releasing activity of IL-8 may play a role in the modulation of inflammation.

Anti-myeloperoxidase antibodies enhance phagocytosis, IL-8 production, and glucose uptake of polymorphonuclear neutrophils rather than anti-proteinase 3 antibodies leading to activation-induced cell death of the neutrophils

Anti-neutrophil cytoplasmic antibodies (ANCA) not only are triggered by target protein myeloperoxidase (MPO) and proteinase 3 (PR3) of polymorphonuclear neutrophil (PMN) but also react with primed PMN to exert the inflammatory process in vasculitis syndrome. To clarify the crucial role of PMN in ANCA-associated vasculitis and the related mechanism, PMN was cultured with monoclonal antibody MPO–ANCA and PR3–ANCA to determine the function of phagocytosis, Interleukin- 8 (IL-8) production, glucose uptake, and TNF-related apoptosis induced ligand (TRAIL) production. The spontaneous membrane expression of MPO and PR3 on PMN could be significantly increased by lipopolysaccharide (LPS) and TNF-α, but not by IL-8 or GRO-α. The PMN-stimulating activity of ANCA was demonstrated by enhancing phagocytosis, IL-8 production, and glucose uptake that was more prominent by MPO–ANCA. The PMN stimulation by ANCA was not through protein kinase, H2O2, or superoxide anion radicals as their inhibitors exerted no effect on ANCA-mediated activation. On the other hand, ANCA also accelerated PMN apoptosis and increased TRAIL production. These results demonstrate that activation-induced cell death (AICD) mechanism could be initiated in PMN with existence of ANCA. In conclusion, MPO–ANCA is more potent in stimulating PMN than PR3–ANCA. ANCA-activated PMN is not only responsible for the amplified inflammatory process in blood vessel but also initiates immune circuit via triggered macrophage/monocyte by apoptotic PMN through the mechanism of AICD elicited by ANCA.

Pigmented eccrine poroma with enhanced endothelin-1 expression: implications for mechanism of hyperpigmentation

which excluded systemic disease. As there were no remnants of lesion, radiotherapy was not performed. Mycophenolate mofetil and tacrolimus ANH were reduced to half the previous dosage. There was no recurrence at 12-month follow-up. Cutaneous CD30+ ALTCL is characterized by the expression of CD30 (an activation marker for B or T cells) in more than 75% of cells, and can be subdivided mainly into a primary cutaneous form, defined by skin-only involvement at presentation, or a systemic form, with secondary skin involvement from a node-based lymphoma, or following transformation of mycosis fungoides. The localization of PTLs in the skin, as well as the CD30+ ALTCL type, are very uncommon. To our knowledge, only five cases of CD30+ PT ALTCL have been reported to date: three in kidney recipients, one in a heart transplant and the other in a combined liver and heart transplantation recipient. Whereas classical primary cutaneous CD30+ ALTCL usually carries a good prognosis, CD30+ PT ALTCLs seem to pursue an aggressive course: the previously reported cases were characterized by multiple lesions at presentation and ⁄or a rapid appearance of new nodules within a few months. In our patient, there was a unique tumour at presentation, and no further lesions appeared within 12 months, although we think that a longer follow-up is necessary to evaluate the clinical behaviour more thoroughly. We think that the small size of the lesion was the most favourable prognostic factor in our case, as it allowed for a complete excision of tumour. We also found strong positivity for MUM1 ⁄ IRF4, which is thought to be crucial for lymphoid development and has been found to be strongly expressed in various types of leukaemia, Band T-cell lymphomas, including ALTCL. MUM1 ⁄ IRF4 expression is thought to be helpful for diagnostic purposes, whereas its prognostic role is controversial, probably depending on the type of leukaemia ⁄ lymphoma considered. MUM1 ⁄ IRF4 was not investigated in the previously reported cases of CD30+ PT ALTCLs; it could be worthwhile to study its expression on a larger series of PTLs. The unusual clinical behaviour and histotype and the immunophenotype of our case may add knowledge to the spectrum of PTLs.

Psoriatic patients with arthropathy show significant expression of free HLA class I heavy chains on circulating monocytes: a potential role in the pathogenesis of psoriatic arthropathy

Backgroundu2003 Surface free heavy chains on monocytes were recently implicated in playing a role in the pathogenesis of several forms of arthritis.

The cytotoxic effect of neonatal lupus erythematosus and maternal sera on keratinocyte cultures is complement‐dependent and can be augmented by ultraviolet irradiation

Summary To elucidate the role of autoantibodies and ultraviolet (UV) exposure in the pathogenesis of the skin lesions in neonatal lupus erythematostis (NLE). keratinocytes were cultured, as the target cells, from a patient with NLE and from a normal neonate. We demonstrated that the expression of nuclear/cytoplasmic Ro/SSA and La/SSB molecules on to the surface of NLE keratinocytes occurred to a much greater extent than that on normal keratinocytes. A dose of 200 ml/cm2 UVB irradiation on NLE keratinocytes induced a 2.5–3‐fold increase in Ro/SSA and La/SSB expression compared to non‐irradiated cells. Sera derived from both the NLE patient and from his mother exhibited a cytotoxie effect on NLE keratinocytes, but not on control cells, in the presence of complement. Furthermore, the cytotoxieity of the sera was enhanced on UVB‐irradiated NLE keratinocytes. whereas it had no cytotoxie efects on UVB‐irradiated control cells. This suggests that the abnormal expression of both Ro/SSA and La/SSB on the surface membrane of NLE keratinocytes induces the autoantibodies and complements to injure the cells. This complement‐mediated cytotoxic effect can be augmented by UV irradiation, a concept not incompatible with the exacerbation of the skin eruption in sun‐exposed skin sites.