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Biomedical subjects

Hidehisa Saeki

Publications and source records attributed to Hidehisa Saeki.

At least 37 records · Page 2Linked to original sources
PubMed2004

Enhanced TARC production by dust-mite allergens and its modulation by immunosuppressive drugs in PBMCs from patients with atopic dermatitis.

BACKGROUND: Thymus and activation regulated chemokine (TARC) is a CC chemokine that attracts CCR4+ T cells. We reported previously that TARC is an important chemokine that defines Th2 imbalance in the pathogenesis of atopic dermatitis (AD). OBJECTIVES: This study was undertaken to clarify TARC producing cells in peripheral blood mononuclear cells (PBMCs), the regulation of dust mite-allergen clude extract (DME) and different immunosuppressive drugs (Tacrolimus (FK506), cyclosporine (CsA), dexamethasone (Dex)) on TARC production by peripheral PBMCs from AD patients in vitro. METHODS: Monocyte derived dendritic cells (MoDCs) were generated from and TARC mRNA levels were examined and comapared with those from T cells in PBMCs from AD patients. PBMCs were cultured with or without DME and/or immunosuppressive drugs (Tacrolimus, CsA, Dex) for 7 days and TARC levels were measured. RESULTS: PBMCs from AD patients which were cultured with DME stimulation for 7 days showed significantly higher levels of TARC production than those from healthy controls. RT-PCR demonstrated that TARC mRNA was expressed in CD4+ T cells, CD8+ T cells and MoDCs. Tacrolimus, CsA and Dex individually suppressed TARC production by PBMCs from AD patients which were co-cultured with DME for 7 days. Gel shift analysis revealed differential inhibitory effects of these immunosuppressive drugs on NFkappaB activity in PBMCs from AD patients. CONCLUSION: Our data demonstrate that TARC producing cells are MoDCs, T cells as well as epidermal keratinocytes in AD. We suggest that MoDCs might regulate the immune responses by attracting T cells and CD25+ T cells in the pathogenesis of AD. We also showed the important role of DME on TARC production and the inhibitory effect of the immunosuppressive drugs on TARC production by PBMCs from AD patients, that can regulate ongoing immune responses in the pathogenesis of AD.

Adult↗
PubMed2004

Differential expression and function of Toll-like receptors in Langerhans cells: comparison with splenic dendritic cells.

Toll-like receptors are key elements in pathogen recognition by the host immune system. Although the expression pattern and functions of Toll-like receptors have been studied in a variety of cytokine-induced dendritic cells, it remains unknown whether Toll-like receptor stimulation influences maturation and cytokine production of authentic Langerhans cells. We purified murine epidermal Langerhans cells along with splenic dendritic cell using a panning method. Langerhans cells expressed Toll-like receptor 2, 4, and 9 but not 7, the pattern of which suggests Langerhans cells are the closest to one of the murine dendritic cell lineage, CD11c+11b+8 alpha-4-. Then we stimulated Toll-like receptor 2, 4, and 9 with the corresponding ligand, Staphylococcus aureus Cowan 1, lipopolysaccharide, and CpG, and found that all of these stimuli upregulated expression of B7-1 and B7-2 in splenic dendritic cells but not in Langerhans cells. As in human Langerhans cells, stimulation of murine Langerhans cells with Staphylococcus aureus Cowan 1, lipopolysaccharide, and CpG overall resulted in T helper 1-polarizing cytokine production (namely, induction of IL-12p40 and inhibition of TARC (thymus and activation-regulated chemokine)/CCL17). Exceptionally, lipopolysaccharide exhibited no effect on IL-12p40 production by Langerhans cells and inhibited IL-12p40 production by splenic dendritic cells. These results may represent the functional heterogeneity between Langerhans cells and splenic dendritic cells, and are important for better understanding of innate immunity to bacterial infections differentially regulated in the skin and spleen. MeSH terms: Toll-like receptors, Langerhans cells, dendritic cells.

Animals↗
PubMed2004

Lack of association of CCR4 single nucleotide polymorphism with atopic dermatitis in Japanese patients.

CCR4, a member of the CC chemokine receptor family, is believed to play an important role in the pathogenesis of atopic dermatitis. To examine whether CCR4 single nucleotide polymorphism (SNP) is associated with susceptibility to atopic dermatitis, we investigated the allele and genotype frequencies of C1014T SNP of CCR4 in 198 Japanese patients with atopic dermatitis and controls by a PCR-restriction fragment length polymorphism method. There was no significant difference in allele or genotype frequencies between patients with atopic dermatitis and controls. Serum IgE levels and peripheral blood eosinophil counts were not significantly different among genotypes. There was also no significant difference in allele or genotype frequencies between the patient subgroup with and without asthma, with mild or moderate disease, with and without family history of atopic dermatitis, or with and without family history of atopic disorders. C1014T SNP of CCR4 does not appear to be associated with susceptibility to atopic dermatitis in Japanese patients.

Adolescent↗
PubMed2004

The -431C>T polymorphism of thymus and activation-regulated chemokine increases the promoter activity but is not associated with susceptibility to atopic dermatitis in Japanese patients.

BACKGROUND: Thymus and activation-regulated chemokine (TARC) plays an important role in the pathogenesis of atopic dermatitis (AD). We recently detected the single nucleotide polymorphism (SNP) (-431C>T) in the 5'-flanking region of TARC gene. OBJECTIVES: To examine whether the -431C>T SNP of the TARC gene is associated with susceptibility to AD and whether it affects the promoter activity of the TARC gene. METHODS: We investigated the genotype and allele frequencies of the SNP in 193 AD patients and 158 healthy controls by polymerase chain reaction-restriction fragment length polymorphism method. We compared the promoter activities between TARC promoter carrying 431C and that carrying -431T by transient-transfection assay in DJM-1 cell line. RESULTS: There were no significant differences in genotype or allele frequencies between AD patients and controls (genotype: P = 0.38, allele: P = 0.22). Luciferase activity was higher in -431T constructs than in -431C constructs (2.3-fold, P = 9.5 x 10(-6)). CONCLUSION: These results suggest that the -431C>T SNP of the TARC gene enhances the promoter activity of TARC gene but is not associated with susceptibility to AD in Japanese population.

Adolescent↗
PubMed2004

The lesional skin of linear IgA bullous dermatosis expresses growth-regulated peptide (GRO)-alpha.

The patient was a 62-year-old man with erythema with tense vesiculobullae and erosions on the bilateral elbows, right knee, and one buttock. A skin biopsy specimen revealed subepidermal blister formation with a predominant infiltration of neutrophils and papillary neutrophilic microabscesses. Direct immunofluorescence study showed linear deposition of IgA and weak deposition of IgG at the basement membrane zone of the lesional skin, and indirect immunofluorescence study showed linear deposition of IgA at the epidermal side of the 1M NaCl-separated normal skin. He was diagnosed with linear IgA bullous dermatosis. Immunohistochemical study revealed that the lesional and perilesional keratinocytes expressed growth-regulated peptide (GRO) -alpha, a potent chemoattractant for neutrophils. This suggests that GRO-alpha plays a role in the infiltration of neutrophils into the lesional skin and in bulla formation in linear IgA bullous dermatosis.

Autoantibodies↗
PubMed2004

High-frequency ultrasound as a useful device in the preliminary differentiation of lichen sclerosus et atrophicus from morphea.

High-frequency ultrasound diagnostic equipment (HFUS) using probes with frequencies above 15-MHz has been utilized conventionally in preoperative assessments and postoperative follow-up of skin tumors. The advent of probes with even higher frequencies (up to 30-MHz) has widened the clinical applications of HFUS to inflammatory dermatoses which are histologically confined to the epidermis and upper dermis, such as psoriasis and atopic dermatitis. Ultrasound imaging has the advantage of being a noninvasive and relatively inexpensive technology that is quick and easy to perform. In addition, information obtained from HFUS is unique and useful for clinical diagnosis and evaluation for various skin disorders. We believe that HFUS has the potential to become a powerful tool for either clinical or investigative dermatology. Herein, we present a case of lichen sclerosus et atrophicus (LSA) to which we applied HFUS before skin biopsy and obtained substantial information for the differential diagnosis from morphea, and we reemphasize the usefulness of HFUS in studying the inflammatory skin disorders.

Biopsy, Needle↗
PubMed2003

Variations in the human Th2-specific chemokine TARC gene.

Th2-specific chemokine thymus and activation-regulated chemokine (TARC)/CC chemokine ligand (CCL)17 is highly implicated in the pathogenesis of Th-2-dominated allergic diseases such as bronchial asthma (BA) and atopic dermatitis (AD). We performed polymorphism screening of the coding and promoter regions of the TARC gene. We found two rare variations in the coding region of exon 3 (2134C>T and 2037G>A) and a single nucleotide polymorphism (SNP) in the 5'-flanking region (-431C>T). Individuals carrying the 431T allele showed significantly increased serum levels of TARC compared with those not carrying the 431T allele, suggesting that this SNP has functional significance. However, when the genotypes at the SNP site were determined for 158 healthy individuals, 105 patients with BA and 148 patients with AD, we observed no significant association of the SNP with susceptibility to BA or AD.

Asthma↗
PubMed2003

Both IL-4 and IL-13 inhibit the TNF-alpha and IFN-gamma enhanced MDC production in a human keratinocyte cell line, HaCaT cells.

BACKGROUND: Macrophage-derived chemokine (MDC) is a Th2 type chemokine and its receptor CC chemokine receptor 4 (CCR4) is preferentially expressed on Th2 cells. Recent reports demonstrated that MDC is expressed not only by macrophages, dendritic cells and lymphocytes, but also by cultured human keratinocytes (KCs). However, the regulation of MDC production in KCs by various cytokines has not been well documented. OBJECTIVE: In this study, we investigated how Th1/Th2 cytokines regulate MDC production in a human KC cell line, HaCaT cells. METHODS: HaCaT cells were cultured with or without various cytokines for 24 h and RT-PCR was performed using these cells to evaluate MDC mRNA levels. ELISA was carried out using supernatant of HaCaT cells to calculate secreted MDC protein levels. RESULTS: MDC mRNA was weakly expressed in HaCaT cells, and upon stimulation with TNF-alpha or IFN-gamma, MDC expression was strongly upregulated. The supernatant MDC levels when stimulated with TNF-alpha or IFN-gamma were significantly higher than those without stimulation, and were synergistically increased when stimulated with a combination of TNF-alpha and IFN-gamma. Both interleukin-4 (IL-4) and IL-13 inhibited TNF-alpha and IFN-gamma enhanced MDC production in HaCaT cells in a dose-dependent manner. CONCLUSION: Th2-type cytokines IL-4 and IL-13 downregulate the production of MDC, a Th2 type chemokine, by KCs. This may partially contribute to maintaining Th1/Th2 balance in inflammatory skin diseases like atopic dermatitis.

Anti-Inflammatory Agents↗
PubMed2003

Human keratinocytes express fractalkine/CX3CL1.

BACKGROUND: fractalkine/CX3CL1 is a unique chemokine that has properties of both chemoattractants and adhesion molecules. The major source of this chemokine in the skin is still controversial. OBJECTIVE: studies were undertaken to determine the expression of fractalkine in human skin. METHODS: RT-PCR, Western blotting, and immunostaining were performed with normal human epidermal keratinocytes (NHEK) and HaCaT cells, human keratinocyte cell line, for the presence of fractalkine. Biopsy specimens of normal and diseased skin were also investigated. RESULTS: we identified that NHEK and HaCaT cells expressed fractalkine mRNA and protein. The combination of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma upregulated their expression by NHEK. Immunohistochemistry demonstrated fractalkine expression in keratinocytes in lichen planus and psoriasis vulgaris. RT-PCR also showed that lesional skin of psoriatic patients expressed higher levels of fractalkine mRNA than non-lesional skin from the same patients. CONCLUSION: these results suggests that keratinocytes strongly express fractalkine in lichen planus and psoriasis vulgaris and that the fractalkine-CXC3CR1 system in the diseased skin can be a target for the treatment.

Cell Line↗
PubMed2003

Analysis of gene mutations in three cases of dermatofibrosarcoma protuberans (DFSP): ordinary DFSP, DFSP with fibrosarcomatous lesion (DFSP-FS) and lung metastasis of DFSP-FS.

BACKGROUND: Fusion of the collagen type I alpha 1 (COL1A1) gene with the platelet-derived growth factor B-chain (PDGFB) gene has been pointed out in dermatofibrosarcoma protuberans (DFSP). Various exons of the COL1A1 gene have been shown to be involved in the fusion with exon 2 of the PDGFB gene. OBJECTIVE: We studied the breakpoints of the COL1A1 gene using the tumor specimens from three patients with DFSP. METHODS: Reverse transcriptase-polymerase chain reaction (PCR) was performed using cultured DFSP tumor cells or frozen tissue. Nucleotide sequence analysis was carried out using the PCR products to identify the breakpoints. RESULTS: Cases 1, 2 and 3 were diagnosed as ordinary DFSP, DFSP with fibrosarcomatous lesion (DFSP-FS) and lung metastasis of DFSP-FS, respectively. The COL1A1-PDGFB fusion transcripts were detected from the tumor specimens. Sequence analysis revealed that the ends of exons 42, 29 and 38 in the COL1A1 gene were fused with the start of exon 2 in the PDGFB gene in case 1, 2 and 3, respectively. CONCLUSION: This study identified a novel COL1A1 breakpoint, namely, exon 42 of the COL1A1 gene. Detection of the aberrant fusion transcript seems to be useful at differential diagnosis both in primary and metastatic lesions.

Adolescent↗
PubMed2003

Increased serum cutaneous T cell-attracting chemokine (CCL27) levels in patients with atopic dermatitis and psoriasis vulgaris.

BACKGROUND: Both atopic dermatitis (AD) and psoriasis vulgaris (PsV) are characterized as chronic and relapsing inflammatory skin diseases associated with various immunologic abnormalities. Cutaneous T cell-attracting chemokine (CTACK; CCL27) is a member of the CC chemokine family and a functional ligand for CC chemokine receptor 10. It is selectively expressed in skin and attracts CC chemokine receptor 10-expressing skin-homing memory T cells. The epidermal keratinocyte is a main source of CTACK, suggesting the involvement of various inflammatory skin diseases. OBJECTIVE: The purpose of this investigation was to clarify whether CTACK produced by keratinocytes is detected in the sera of patients with AD and PsV and to examine the correlation between the serum CTACK levels and disease activity of patients with AD and PsV. METHODS: We measured the serum CTACK levels in 50 patients with AD, 30 patients with PsV, and 22 healthy control subjects. We also divided 50 patients with AD into 3 groups (ie, those with mild, moderate, and severe disease) and compared them among 3 categories. Moreover, we compared the serum CTACK levels of patients with AD and PsV with clinical or laboratory data. Immunohistochemical staining of CTACK and IFN-induced protein of 10 kd (IP-10; CXCL10) was performed on the lesional skin of patients with AD and PsV. RESULTS: The serum CTACK levels in patients with AD and PsV were significantly higher than those in healthy control subjects. The serum CTACK levels in patients with AD significantly correlated with scoring atopic dermatitis (SCORAD) scores, serum soluble IL-2 receptor levels, serum soluble E-selectin levels, serum thymus and activation-regulated chemokine levels, and serum macrophage-derived chemokine levels. Serum CTACK levels in patients with PsV significantly correlated with the serum IP-10 levels but not with the Psoriasis Area and Severity Index score. Immunohistochemical staining showed CTACK was strongly expressed in lesional ke-ratinocytes of patients with AD and PsV, whereas IP-10 was strongly expressed in lesional keratinocytes of patients with PsV and focally in those with AD. CONCLUSION: These results suggest that CTACK might be one of the important chemokines for the pathogenesis of AD and PsV.

Adult↗
PubMed2003

Multiple eruptive dermatofibromas with CD34+ cells in a patient with hypertriglyceridemia.

Multiple eruptive dermatofibromas (MEDF) are rare and have been thought to be associated with altered immunity. It has been reported that dermatofibromas (DFs) are positive for factor X IIIa but not for CD34. In this report, we describe a 34-year-old Japanese woman with MEDF and persistent hypertriglyceridemia. Histopathological examination revealed that several areas in larger nodules, showing higher cellularity and storiform growth pattern, had CD34+ cells. Our case and the review of previous reports suggest that hyperlipidemia, including hypertriglyceridemia, could induce MEDF and that highly cellular areas in DFs are sometimes positive for CD34.

Adult↗
PubMed2003

Lack of association between the promoter polymorphisms at positions -308 and -238 of the tumor necrosis factor alpha gene and psoriasis vulgaris in Japanese patients.

BACKGROUND: Psoriasis features an increased level and activity of tumor necrosis factor alpha (TNF-alpha). The TNF-alpha gene has single nucleotide polymorphisms (SNPs) at positions -308 (-308G>A) and -238 (-238G>A) in the promoter region, and the -238G>A SNP has been reported to be associated with psoriasis vulgaris (PV) and psoriatic arthritis in Caucasians. OBJECTIVE: To examine whether these SNPs are associated with susceptibility to PV in Japanese patients, we investigated the genotype and allele frequencies at each SNP in Japanese PV patients and in controls. METHODS: We examined 163 PV patients and 96 healthy individuals. Genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: No significant association between the genotypes or alleles of these SNPs and susceptibility to PV was observed. CONCLUSION: These SNPs themselves are not associated with susceptibility to PV in the Japanese.

Gene Frequency↗