During a search for keratinocyte differentiation-related genes, we obtained a cDNA fragment from the 5'-untranslated region of a previously identified splicing variant of desmoglein 3 (Dg3). This transcript encodes a protein of 282 amino acids, which corresponds to the N-terminal truncated intracellular domain of Dg3 (Delta NDg3). Northern blot analysis detected a 4.6-kb transcript matching the predicted size of Delta NDg3 mRNA, and Western blot analysis with an antibody raised against the Dg3 C-terminus (H-145) detected a 31-kDa protein. Increased Delta NDg3 expression was observed in differentiating keratinocytes by RT-PCR and Western blot analysis, suggesting that Delta NDg3 is indeed a differentiation-related gene product. In immunohistochemical studies of normal and pathologic tissues, H-145 antibody detected the protein in the cytoplasm of suprabasal layer cells, whereas an antibody directed against the N-terminal region of Dg3 (AF1720) reacted with a membrane protein in the basal layer. In addition, Delta NDg3 transcript and protein were upregulated in psoriatic epidermis, and protein expression appeared to increase in epidermal tumors including Bowen's disease and squamous cell carcinoma. Moreover, overexpression of Delta NDg3 led to increased migration and weakening of cell adhesion. These results suggest that Delta NDg3 have a role in keratinocyte differentiation, and that may be related with tumorigenesis of epithelial origin.
Cell Adhesion ; *Cell Differentiation ; Cell Movement ; Cells, Cultured ; Desmoglein 3/*genetics/*metabolism ; Epidermis/cytology ; Gene Expression ; Humans ; Keratinocytes/*cytology ; Skin Diseases/genetics/metabolism ; gamma Catenin/metabolism

Livedoid vasculopathy is a rare chronic relapsing disorder characterised by recurrent painful thrombotic and vasculitic ulcers on the legs. We present the cases of two Indian women with livedoid vasculopathy that were found to be associated with an underlying factor V Leiden heterozygous mutation. There were no other thrombotic manifestations, and livedoid vasculopathy was the sole presenting feature of the factor V Leiden mutation, although this could also be coincidental. Initial treatment with high-dose immunosuppressive therapy was suboptimal, and the addition of pentoxifylline and antiplatelet therapy was crucial in achieving disease control and remission. These cases highlight the possible association with an underlying prothrombotic disorder, such as factor V Leiden mutation, in patients with livedoid vasculopathy. Although this association is relatively uncommon, it is more relevant to Indian patients, as the presence of factor V Leiden mutation is highest in this ethnicity as compared to the local Malay and Chinese populations.
Adult ; Blood Vessels ; pathology ; DNA ; genetics ; Factor V ; genetics ; metabolism ; Female ; Humans ; Leg Ulcer ; blood ; genetics ; pathology ; Livedo Reticularis ; blood ; diagnosis ; genetics ; Point Mutation ; Polymerase Chain Reaction ; Skin ; blood supply ; Skin Diseases, Vascular ; blood ; genetics ; pathology

Defensins and cathelicidins (LL-37) are major antimicrobial peptides (AMPs) of the innate immune system of the human skin. In normal non-inflamed skin these peptides are negligible, but their expression can be markedly increased in inflammatory skin disease such as psoriasis. We designed this study to identify the expressions of LL-37 in normal human keratinocyte (NHK) and HaCaT cells after exposure to stimulants and to investigate difference of LL-37 expression accompanied with cell differentiation status, and come to understand difference of susceptibility to infection in atopic dermatitis and psoriasis. Expressions of LL-37 in NHKs and HaCaT cells were evaluated by using RT-PCR, Western blotting, and immunohistochemical (IHC) staining at 6, 12, and 24 hr post stimulation after exposure to Ultraviolet B irradiation and lipopolysaccharide. And expression of LL-37 in skin biopsy specimens from patients with atopic dermatitis and psoriasis was determined by immunohistochemical analysis. In time-sequential analyses of LL-37 expression revealed that LL-37 was expressed in NHKs, but not in HaCaT cells. IHC analysis confirmed the presence of abundant LL-37 in the epidermis of psoriasis. Therefore we deduced that expression of LL-37 is affected by UV irradiation, bacterial infection, and status of cell differentiation.
Antimicrobial Cationic Peptides/analysis/*genetics ; Blotting, Western ; Cell Line ; Cells, Cultured ; Comparative Study ; Defensins/analysis/genetics ; Dose-Response Relationship, Drug ; Gene Expression/drug effects/radiation effects ; Humans ; Immunohistochemistry ; Keratinocytes/cytology/*metabolism ; Lipopolysaccharides/pharmacology ; Male ; RNA, Messenger/genetics/metabolism ; Research Support, Non-U.S. Gov't ; Reverse Transcriptase Polymerase Chain Reaction ; Skin/cytology/metabolism ; Skin Diseases/*genetics/metabolism/pathology

Despite the various responses of human skin to female sex hormones, cellular and subcellular targets and the mechanisms of action of estrogen and progesterone in human skin are not well understood. The detection of estrogen receptor (ER) and progesterone receptor (PR) in the skin is of great importance to understand the effect of estrogen and progesterone. In primary cultures of human keratinocytes, expression of ER and PR was monitored by immunocytochemistry and reverse transcriptase polymerase chain reaction (RT-PCR). Paraffin embedded skin tissues were stained with monoclonal antibodies to human ER and PR by immunohistochemistry. Cultured human keratinocytes expressed cytoplasmic PR protein and PR mRNA transcripts. By contrast, ER was detected only at the mRNA level. Suprabasal keratinocytes from samples of pruritic urticarial papules, plaques of pregnancy (PUPPP) and psoriasis were stained positively only for PR, while those from samples of erythema nodosum were negative for both ER and PR. Lesional epidermis of PUPPP showed positive PR immunoreactivity, while nonlesional epidermis did not. No other cells in the normal human skin were stained with ER and PR. The present study suggests that by expressing PR human keratinocytes act as targets for progesterone action.
Adolescence ; Adult ; Aged ; Cells, Cultured ; Female ; Gene Expression ; Human ; Immunoenzyme Techniques ; Infant ; Keratinocytes/metabolism* ; Keratinocytes/cytology ; Male ; Middle Age ; Receptors, Estrogen/genetics ; Receptors, Estrogen/biosynthesis ; Receptors, Progesterone/genetics* ; Receptors, Progesterone/biosynthesis ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA/methods ; Skin/pathology ; Skin/metabolism ; Skin Diseases/metabolism

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.
Adult ; Cell Proliferation ; Chemokine CXCL12 ; genetics ; Epidermal Cells ; Epidermis ; pathology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Fibroblasts ; metabolism ; Gene Expression Regulation ; Humans ; Keratinocytes ; cytology ; pathology ; Signal Transduction ; Skin Diseases ; genetics ; pathology

OBJECTIVESTo study the clinicopathologic features of Rosai-Dorfman disease (RDD), expression of various antigens, human herpes virus type 8 (HHV8), human papillomavirus (HPV)-DNA and Epstein-Barr virus (EBV)-mRNA, and compare the findings with those in the literature.

METHODSThe clinicopathologic findings of 16 Rosai-Dorfman disease cases were retrospectively reviewed. Immunohistochemical study for S-100 protein, CD68 (PG-M1), CD163, CD21, CD1a, CD20, CD45RO, CD4, CD8, M-CSF and HHV8 was carried out in 9 of the 16 cases. In-situ hybridization for EBV-mRNA and HPV-DNA was also performed.

RESULTSThe male-to-female ratio of the patients was 4.33:1. Amongst the 16 cases studied, 62.5% (10/16) presented nodal RDD, with cervical lymph node predominantly involved. Half of these cases had affected lymph nodes in more than one anatomic site. Extranodal RDD represented 37.5% (6/16) of the cases. The relapse rate of extranodal RDD was higher than that of nodal RDD. Histologically, nodal RDD was characterized by dilated sinuses filled with large polygonal histiocytes which contained lymphocytes and plasma cells. For extranodal lesions, various degrees of stromal fibrosis were seen in association with mixed inflammatory cells (especially plasma cells). The large polygonal histiocytes varied in number and were distributed in clusters or patches. Immunohistochemical study showed that the abnormal histiocytes were strongly positive for S-100 protein. They also expressed CD68, CD163 and M-CSF, but were negative for CD1a, CD21 and HHV8. The lymphocytes in cytoplasm of these histiocytes were positive for both T and B cell markers (with T cell predominance, including a mixture of CD4- and CD8-positive cells). HPV-DNA and EBV-mRNA were not detected by in-situ hybridization. To date, 62 cases of RDD have been reported in mainland China, including 34 cases of nodal RDD and 18 cases of extranodal RDD. The remaining 10 cases involved both lymph nodes and extranodal sites. Compared with overseas reports, RDD occurring in China tended to affect older patients and with slight male predilection.

CONCLUSIONSRosai-Dorfman disease is relatively rare in China. Pathologic diagnosis of extranodal RDD may be difficult. The demographic data of RDD in China, including age and sex of patients, are different from those in the literature.

Adolescent ; Adult ; Aged ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Bone Diseases ; metabolism ; pathology ; virology ; Child ; DNA, Viral ; analysis ; Female ; Follow-Up Studies ; Herpesvirus 8, Human ; genetics ; isolation & purification ; Histiocytosis, Sinus ; metabolism ; pathology ; virology ; Humans ; Immunohistochemistry ; Lymph Nodes ; pathology ; Macrophage Colony-Stimulating Factor ; metabolism ; Male ; Middle Aged ; Nose Diseases ; metabolism ; pathology ; virology ; RNA, Viral ; analysis ; Receptors, Cell Surface ; metabolism ; Retrospective Studies ; S100 Proteins ; metabolism ; Skin Diseases ; metabolism ; pathology ; virology ; Young Adult

12(S)-Hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT) is an enzymatic product of prostaglandin H2 (PGH2) derived from cyclooxygenase (COX)-mediated arachidonic acid metabolism. Despite the high level of 12-HHT present in tissues and bodily fluids, its precise function remains largely unknown. In this study, we found that 12-HHT treatment in HaCaT cells remarkably down-regulated the ultraviolet B (UVB) irradiation-induced synthesis of interleukin-6 (IL-6), a pro-inflammatory cytokine associated with cutaneous inflammation. In an approach to identify the down-stream signaling mechanism by which 12-HHT down-regulates UVB-induced IL-6 synthesis in keratinocytes, we observed that 12-HHT inhibits the UVB-stimulated activation of p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-kappaB). In addition, we found that 12-HHT markedly up-regulates MAPK phosphatase-1 (MKP-1), a critical negative regulator of p38 MAPK. When MKP-1 was suppressed by siRNA knock-down, the 12-HHT-mediated inhibitory effects on the UVB-stimulated activation of p38 MAPK and NF-kappaB, as well as the production of IL-6, were attenuated in HaCaT cells. Taken together, our results suggest that 12-HHT exerts anti-inflammatory effect via up-regulation of MKP-1, which negatively regulates p38 MAPK and NF-kappaB, thus attenuating IL-6 production in UVB-irradiated HaCaT cells. Considering the critical role of IL-6 in cutaneous inflammation, our findings provide the basis for the application of 12-HHT as a potential anti-inflammatory therapeutic agent in UV-induced skin diseases.
Anti-Inflammatory Agents, Non-Steroidal/pharmacology ; Cell Line ; Dual Specificity Phosphatase 1/biosynthesis/genetics ; Enzyme Activation ; Fatty Acids, Unsaturated/*pharmacology ; Humans ; Interleukin-6/*biosynthesis ; Keratinocytes/*metabolism/radiation effects ; NF-kappa B/metabolism ; RNA Interference ; RNA, Small Interfering ; Receptors, Leukotriene B4/genetics ; Signal Transduction/drug effects ; Skin Diseases/drug therapy ; *Ultraviolet Rays ; Up-Regulation ; p38 Mitogen-Activated Protein Kinases/metabolism

The aim of this study was to investigate the clinical, pathological and biological features of biphenotypic acute leukemia. The morphology of tumor cells was observed by bone marrow examination; the immunophenotype was assayed by flow cytometry and immunohistochemistry; the chromosomal aberrations were detected by conventional chromosomal analysis and RT-multiplex nested PCR. The results showed that extramedullary skin lesions and myelodysplasia occurred before the onset of overt disease. At the time of diagnosis, this case had more than 30% blasts in bone marrow with meningeal involvement. Large-sized tumor cells predominated morphologically over other cells. Flow cytometry revealed the co-expression of myeloid antigens (cMPO, CD33 and CD117) and T-lymphoid antigens (cCD3, CD5, CD7, dual expression of CD4 and CD8). Immunohistochemical staining showed that CD43 and CD99 were strong positive which define the earliest hematopoietic progenitors. Partial tandem duplication of the MLL gene could be detected with normal cytogenetic method. All above-mentioned results led to the diagnosis of biphenotypic acute leukemia. It is concluded that the biphenotypic acute leukemia is an uncommon type of leukemia which may be preceded by myelodysplastic syndrome and has aggressive clinical and biological behavior. Immunophenotype, cytogenetics and molecular analysis can contribute to early diagnosis of BAL and evaluation of prognosis.
12E7 Antigen ; Acute Disease ; Antigens, CD ; metabolism ; Cell Adhesion Molecules ; metabolism ; Child, Preschool ; Diagnosis, Differential ; Histone-Lysine N-Methyltransferase ; Humans ; Immunophenotyping ; Leukemia ; diagnosis ; genetics ; Leukosialin ; metabolism ; Male ; Myelodysplastic Syndromes ; complications ; Myeloid-Lymphoid Leukemia Protein ; genetics ; Skin Diseases ; complications ; Tandem Repeat Sequences