A Case of Possible Concurrence of Dermatitis Herpetiformis and Linear Immunoglobulin A / Immunoglobulin G Bullous Dermatosis.

Linear immunoglobulin (Ig) A bullous dermatosis (LABD), one subtype of subepidermal autoimmune bullous skin diseases (AIBDs), is characterized by linear deposit of only IgA along the basement membrane zone (BMZ) on direct immunofluorescence (DIF) (1,2). Patients showing linear deposits of both IgA and IgG are diagnosed with linear IgA/IgG bullous dermatosis (LAGBD) (3,4). Dermatitis herpetiformis (DH) is another type of subepidermal AIBD characterized by clinically pruritic erythematous skin lesions with vesicles on the elbows, knees, and buttocks with granular IgA deposits of IgA by DIF (5). In this study, we report a Japanese case of a patient who showed possible concurrence of DH and LAGBD based on clinical, histological, and immunological findings

A Case of Possible Concurrence of Dermatitis Herpetiformis and Linear Immunoglobulin A / Immunoglobulin G Bullous Dermatosis.

Linear immunoglobulin (Ig) A bullous dermatosis (LABD), one subtype of subepidermal autoimmune bullous skin diseases (AIBDs), is characterized by linear deposit of only IgA along the basement membrane zone (BMZ) on direct immunofluorescence (DIF) (1,2). Patients showing linear deposits of both IgA and IgG are diagnosed with linear IgA/IgG bullous dermatosis (LAGBD) (3,4). Dermatitis herpetiformis (DH) is another type of subepidermal AIBD characterized by clinically pruritic erythematous skin lesions with vesicles on the elbows, knees, and buttocks with granular IgA deposits of IgA by DIF (5). In this study, we report a Japanese case of a patient who showed possible concurrence of DH and LAGBD based on clinical, histological, and immunological findings

Keratinocyte Responsive Element 3: Analysis of a Keratinocyte-specific Regulatory Sequence in the 230-kDa Bullous Pemphigoid Antigen Gene Promoter

The 230-kDa bullous pemphigoid antigen gene is expressed primarily, if not exclusively, in basal keratinocytes of the epidermis. Keratinocyte responsive element 3, a cis-element at position –216 to –197 of the human 230-kDa bullous pemphigoid antigen gene promoter, confers tissue-specific expression to this gene (Tamai et al: J Biol Chem 270:7609–7614, 1995). In this study, we investigated the functional characteristics of keratinocyte responsive element 3 on the 230-kDa bullous pemphigoid antigen gene core promoter by transient transfections of cultured normal human keratinocytes and normal human fibroblasts, as well as of lung carcinoma (A549), osteosarcoma (OST), and gastric adenocarcinoma (GT3TKB) cell lines. A 230-kDa bullous pemphigoid antigen gene core promoter/luciferase reporter gene plasmid construct, pBPL, was modified to develop a series of constructs (pKBPL–p4KBPL), which have insertions of one, two, three, or four tandem repeats of keratinocyte responsive element 3, and these plasmids were used in transient transfections of the cultured cells. The promoter activities of pKBPL–p4KBPL constructs, relative to pBPL, in normal human keratinocytes were 7.6-, 15.5-, 4.6-, and 2.7-fold higher, respectively, whereas no upregulatory effect by keratinocyte responsive element 3 insertion was observed in other cell lines tested. prKBPL, a plasmid constructed with keratinocyte responsive element 3 in reverse orientation, showed essentially no activity in normal human keratinocytes. Insertion of a random 20 bp sequence between keratinocyte responsive element 3 and the 230-kDa bullous pemphigoid antigen gene core promoter resulted in about 40% reduction of luciferase activity in normal human keratinocytes. These data suggest that keratinocyte responsive element 3 functions as a position-, copy number-, and orientation-dependent cis-element contributing to tissue-specific regulation of the 230-kDa bullous pemphigoid antigen gene

Fibroblasts Show More Potential as Target Cells than Keratinocytes in COL7A1 Gene Therapy of Dystrophic Epidermolysis Bullosa

Dystrophic epidermolysis bullosa (DEB) is an inherited blistering skin disorder caused by mutations in the type VII collagen gene (COL7A1). Therapeutic introduction of COL7A1 into skin cells holds significant promise for the treatment of DEB. The purpose of this study was to establish an efficient retroviral transfer method for COL7A1 into DEB epidermal keratinocytes and dermal fibroblasts, and to determine which gene-transferred cells can most efficiently express collagen VII in the skin. We demonstrated that gene transfer using a combination of G protein of vesicular stomatitis virus-pseudotyped retroviral vector and retronectin introduced COL7A1 into keratinocytes and fibroblasts from a DEB patient with the lack of COL7A1 expression. Real-time polymerase chain reaction analysis of the normal human skin demonstrated that the quantity of COL7A1 expression in the epidermis was significantly higher than that in the dermis. Subsequently, we have produced skin grafts with the gene-transferred or untreated DEB keratinocytes and fibroblasts, and have transplanted them into nude rats. Interestingly, the series of skin graft experiments showed that the gene-transferred fibroblasts supplied higher amount of collagen VII to the new dermal–epidermal junction than the gene-transferred keratinocytes. An ultrastructural study revealed that collagen VII from gene-transferred cells formed proper anchoring fibrils. These results suggest that fibroblasts may be a better gene therapy target of DEB treatment than keratinocytes

Dominant and Recessive Compound Heterozygous Mutations in Epidermolysis Bullosa Simplex Demonstrate the Role of the Stutter Region in Keratin Intermediate Filament Assembly

Keratin intermediate filaments are important cytoskeletal structural proteins involved in maintaining cell shape and function. Mutations in the epidermal keratin genes, keratin 5 or keratin 14 lead to the disruption of keratin filament assembly, resulting in an autosomal dominant inherited blistering skin disease, epidermolysis bullosa simplex (EBS). We investigated a large EBS kindred who exhibited a markedly heterogeneous clinical presentation and detected two distinct keratin 5 mutations in the proband, the most severely affected. One missense mutation (E170K) in the highly conserved helix initiation peptide sequence of the 1A rod domain was found in all the affected family members. In contrast, the other missense mutation (E418K) was found only in the proband. The E418K mutation was located in the stutter region, an interruption in the heptad repeat regularity, whose function as yet remains unclear. We hypothesized that this mutated stutter allele was clinically silent when combined with the wild type allele but aggravates the clinical severity of EBS caused by the E170K mutation on the other allele. To confirm this in vitro, we transfected mutant keratin 5 cDNA into cultured cells. Although only 12.7% of the cells transfected with the E170K mutation alone showed disrupted keratin filament aggregations, significantly more cells (30.0%) cotransfected with both E170K and E418K mutations demonstrated keratin aggregation (p < 0.05). These transfection assay results corresponded to the heterogeneous clinical findings of the EBS patient in this kindred. We have identified the first case of both compound heterozygous dominant (E170K) and recessive (E418K) mutations in any keratin gene and confirmed the significant involvement of the stutter region in the assembly and organization of the keratin intermediate filament network in vitro

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2010: General view of the pathogens\u27 antibacterial susceptibility

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from patients in Japan, was conducted by Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases and Japanese Society for Clinical Microbiology in 2010.The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period from January and April 2010 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical and Laboratory Standard Institutes using maximum 45 antibacterial agents.Susceptibility testing was evaluable with 954 strains (206 Staphylococcus aureus, 189 Streptococcus pneumoniae, 4 Streptococcus pyogenes, 182 Haemophilus influenzae, 74 Moraxella catarrhalis, 139 Klebsiella pneumoniae and 160 Pseudomonas aeruginosa). Ratio of methicillin-resistant S.aureus was as high as 50.5%, and those of penicillin-intermediate and -resistant S.pneumoniae were 1.1% and 0.0%, respectively. Among H.influenzae, 17.6% of them were found to be β-lactamase-non-producing ampicillin (ABPC)-intermediately resistant, 33.5% to be β-lactamase-non-producing ABPC-resistant and 11.0% to be β-lactamase-producing ABPC-resistant strains. Extended spectrum β-lactamase-producing K.pneumoniae and multi-drug resistant P.aeruginosa with metallo β-lactamase were 2.9% and 0.6%, respectively.Continuous national surveillance of antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis