Expression of bcl-2 antagonist bak in inflammatory and neoplastic skin diseases

Bak (bcl-2 homologous antagonist/killer) is a proapoptotic member of the ever-expanding bcl-2 gene family, a recently described category of oncogenes that is critical for the regulation of programmed cell death. We investigated the expression of bak in several inflammatory and neoplastic skin diseases in comparison with normal skin. Immunohistochemical analysis revealed positive bak staining in epidermal keratinocytes of normal skin, with the granular layer being stained slightly more strongly than the basal and spinous layers, and in psoriasis vulgaris, lichen planus, actinic keratosis, keratoacanthoma and squamous cell carcinoma. We demonstrated the expression of bak in the follicular infundibulum in contrast to the outer root sheath of the lower follicle, which showed only negative to weak bak expression. Seventeen of 20 basal cell carcinomas examined showed negative immunostaining for bak, and the remaining three basal cell carcinomas showed only partial weak positivity, mainly in the palisading layers of some tumour formations. Immunoblot analysis using cultured normal human epidermal keratinocytes revealed the presence of bak protein in both undifferentiated and differentiated keratinocytes. The results of our study suggest that the loss of bak expression, in conjunction with the previously reported overexpression of bcl-2, might contribute to the pathogenesis of basal cell carcinoma.

Prolidase activity in chronic wound and blister fluids

We investigated prolidase activity in samples derived from wound fluid as well as blister fluid. Prolidase activity was elevated in fluid samples collected from wounds over the levels in sera collected from patients with chronic wounds (P < 0.05). Prolidase activity was also present in samples taken from blister diseases. However, prolidase activity in blister fluid was not higher than that in sera collected from patients with blister diseases. Our results indicate that prolidase may play a role in wound healing.

Amelioration of prolidase deficiency in fibroblasts using adenovirus mediated gene transfer

Prolidase deficiency is an autosomal recessive inherited disease characterized clinically by frequent infections, mental retardation, and various skin lesions. Fundamental treatments for these manifestations have not been established. We performed adenovirus-mediated gene transfer of human prolidase cDNA into fibroblasts from patients with prolidase deficiency. Infection with the adenovirus vector carrying human prolidase cDNA increased prolidase activity in fibroblasts up to approximately 7.5 times of that of normal control fibroblasts. This indicates the feasibility of adenovirus-mediated gene therapy to treat patients with prolidase deficiency in the future.

Requirement of CD4 T cells for skin graft rejection against thymus leukemia (TL) antigen and multiple epitopes on the TL molecule recognized by CD4 T cells

By selective depletion of CD4 and CD8 T cells in vivo using the respective mAbs, we demonstrate that CD4 T cells are necessary for skin graft rejection against thymus leukemia (TL) Ag. The skin expressing T3b-TL Ag from transgenic C3H Tg.Con.3-1 mice given chimeric H-2Kb/T3b-TL gene was rejected when grafted onto C3H/He recipient mice. Depletion of CD4, but not of CD8, T cells blocked rejection. CD8 CTL were generated in MEM (control)-treated C3H/He recipient mice, while Thy-1+ CD4- CD8- CTL were generated in CD8-depleted recipient mice after rejection. However, no CTL were generated in CD4-depleted or both CD4- and CD8-depleted recipient mice. Thus, the generation of both CD8 and Thy-1+ CD4- CD8- CTL was dependent on CD4 T cells. Ab blocking indicated that both CD8 and Thy-1+ CD4- CD8- CTL were TCR alphabeta and recognized TL Ag. We furthermore demonstrated that CD4 T cells in spleen cells from C3H/He mice that had rejected C3H Tg.Con.3-1 skin showed a weak, but significant, proliferative response to in vitro stimulation with mitomycin C-treated C3H Tg.Con.3-1 spleen cells. Analysis of the reactivity of bulk CD4 T cell lines to 73 synthetic overlapping peptides encompassing the entire T3b-TL molecule showed that CD4 T cells recognized multiple epitopes on the T3b-TL molecule in an APC-dependent manner.

Requirement of CD4 T cells for skin graft rejection against thymus leukemia (TL) antigen and multiple epitopes on the TL molecule recognized by CD4 T cells

By selective depletion of CD4 and CD8 T cells in vivo using the respective mAbs, we demonstrate that CD4 T cells are necessary for skin graft rejection against thymus leukemia (TL) Ag. The skin expressing T3b-TL Ag from transgenic C3H Tg.Con.3-1 mice given chimeric H-2Kb/T3b-TL gene was rejected when grafted onto C3H/He recipient mice. Depletion of CD4, but not of CD8, T cells blocked rejection. CD8 CTL were generated in MEM (control)-treated C3H/He recipient mice, while Thy-1+ CD4- CD8- CTL were generated in CD8-depleted recipient mice after rejection. However, no CTL were generated in CD4-depleted or both CD4- and CD8-depleted recipient mice. Thus, the generation of both CD8 and Thy-1+ CD4- CD8- CTL was dependent on CD4 T cells. Ab blocking indicated that both CD8 and Thy-1+ CD4- CD8- CTL were TCR alphabeta and recognized TL Ag. We furthermore demonstrated that CD4 T cells in spleen cells from C3H/He mice that had rejected C3H Tg.Con.3-1 skin showed a weak, but significant, proliferative response to in vitro stimulation with mitomycin C-treated C3H Tg.Con.3-1 spleen cells. Analysis of the reactivity of bulk CD4 T cell lines to 73 synthetic overlapping peptides encompassing the entire T3b-TL molecule showed that CD4 T cells recognized multiple epitopes on the T3b-TL molecule in an APC-dependent manner.

Expression of keratins (K10 and K17) in steatocystoma multiplex, eruptive vellus hair cysts, and epidermoid and trichilemmal cysts

We compared the patterns of keratin 10 (K10) and keratin 17 (K17) expression in epidermoid cysts, trichilemmal cysts, eruptive vellus hair cysts, and steatocystoma multiplex. Epidermoid cysts expressed K10 and eruptive vellus hair cysts expressed K17, whereas trichilemmal cysts and steatocystoma multiplex showed expression of both K10 and K17. Our findings support the opinion that eruptive vellus hair cysts, which stained negative for K10, and steatocystoma multiplex are distinct entities and not variants of one disorder.

IRF-1 expression in normal human epidermal keratinocytes

Interferon gamma (IFN-gamma) is a potent inducer of cell growth arrest in human epidermal keratinocytes. Interferon regulatory factor-1 (IRF-1), an interferon-inducible gene, is a mediator of interferon action. It has also been suggested that IRF-1 may have a functional role as a tumor suppressor gene and may be associated with the antiproliferative effect of IFN-gamma. We examined the expression of IRF-1 mRNA in normal human epidermal keratinocytes (NHEK). Northern blot analysis demonstrated an increased expression of IRF-1 mRNA by IFN-gamma in NHEKs. This increased expression of IRF-1 mRNA by IFN-gamma was not blocked by treatment with cycloheximide, but was abolished by treatment with actinomycin D. In addition, neither pretreatment with TPA, a protein kinase C (PKC) activator, nor treatment with H7, a PKC inhibitor, affected the induction of IRF-1 mRNA by IFN-gamma. These results indicate that IFN-gamma-induced IRF-1 mRNA in NHEKs is transcriptional and PKC-independent.

Differential expression of human cornifin alpha and beta in squamous differentiating epithelial tissues and several skin lesions

Cornifins/small proline-rich proteins (SPRRs) belong to a family of proline-rich proteins that function as cornified envelope precursors. We report here an immunohistochemical analysis of human cornifin-alpha and -beta expression in several stratified squamous epithelia. In normal human skin, cornifin-alpha was expressed in the granular layer of the epidermis of palmoplantar skin, in the inner lining cells of the follicular infundibulum, and in the inner root sheath of the hair follicle. It was also expressed in the upper squamous layers of the oral, esophageal, and vaginal epithelia. Cornifin-beta was detected in oral, esophageal, and vaginal epithelia, but not in normal skin. Immunoblot analysis revealed quantitative differences in cornifin-alpha expression in skin from different regions. Studies of specimens from various skin diseases showed that (i) cornifin-alpha was upregulated in inflammatory skin diseases, hyperplastic lesions, and in well-differentiated squamous cell carcinomas (SCCs), (ii) the expression of cornifin-beta was absent in inflammatory skin but was detected in highly differentiated keratinocytes in well-differentiated SCCs of the skin and some other hyperproliferative skin lesions, and in SCCs of the oral mucosa and esophagus. Northern blot analysis revealed that cornifin-alpha mRNA was present in all the squamous epithelial tissues studied, whereas cornifin-beta mRNA was expressed in oral mucosal epithelia and verrucous carcinoma of the skin but neither in normal nor in psoriatic skin. These results indicate that (i) the amount of cornifin alpha/SPRR1 expression in normal human skin depends on the body region, (ii) cornifin-alpha/SPRR1, but not cornifin-beta, contributes to the integrity of the hair follicle, and (iii) the expression of cornifin-beta is induced in some hyperplastic skin diseases only when the keratinocytes undergo extensive squamous differentiation.

Producibility of exfoliative toxin and staphylococcal coagulase types of Staphylococcus aureus strains isolated from skin infections and atopic dermatitis

BACKGROUND

Strains of Staphylococcus aureus which cause staphylococcal scalded skin syndrome (SSSS) and bullous impetigo secrete exfoliative toxin (ET). Two antigenically distinct serotypes of ET, ETA and ETB, have been reported.

MATERIALS AND METHODS

Two hundred eighty-three strains of S. aureus isolated from impetigo, SSSS, furuncles (including furunculosis) and atopic dermatitis were examined in terms of the producibility of ET, ET serotypes and coagulase types. We examined ET production and ET serotypes using the polymerase chain reaction with the oligonucleotide primers for eta and etb.

RESULTS

The incidence of ET producers was 69.4% (100/144) in impetigo, 100% (6/6) in SSSS, 2.8% (3/112) in atopic dermatitis and 0% (0/21) in furuncles. ETA alone was produced by 57 strains from impetigo and by 3 strains from atopic dermatitis. ETB alone was produced by 36 strains from impetigo and by all 6 strains from SSSS. Seven strains from impetigo produced both ETA and ETB. Most ETA producers belonged to coagulase type V and most ETB producers to coagulase type I. Impetigo strains mostly belonged to type I or V. All strains from SSSS were classified as type I. Type IV was most frequent among S. aureus isolates from furuncles.

CONCLUSION

These results add to the epidemiological information as to ET producibility and ET serotypes of S. aureus strains isolated from impetigo, SSSS, furunculosis and atopic dermatitis. We have found that there is a relationship between the ET serotypes and the coagulase types of ET-producing strains.

Adhesion of Staphylococcus aureus to horny layer: role of fibrinogen

Staphylococcus aureus cells attach to and invade the epidermis more easily under conditions of abrasion or occlusion or in the presence of irritant dermatitis than when the epidermis is intact. This fact strongly suggests that exuded plasma components may play an important role in the adherence of S. aureus cells to the horny layer. S. aureus cells (Cowan 1 strain, Wood 46 strain, and the protein A-deficient mutant, C7 strain, which was isolated from the Cowan 1 strain) were epicutaneously inoculated on the backs of mice. Biopsy specimens were taken from the mice at 1 h, 3 h, and 6 h after inoculation and examined using immunoelectron microscopy. Gold particles for fibrinogen gathered in a time-dependent manner at the interfaces of S. aureus cells and horny material in the lesions inoculated with the Cowan 1 and C7 strains but not in the lesions inoculated with the Wood 46 strain. These results suggest that fibrinogen plays a role in the binding of S. aureus cells to the horny layer.

Localization of prolidase gene expression in scar tissue using in situ hybridization

We investigated prolidase gene expression in human skin by means of Northern blot analysis and in situ hybridization. Northern blot analysis revealed that an mRNA species that was specific for prolidase was present in cultured human skin fibroblasts and keratinocytes. In situ hybridization using non-isotopic riboprobes labeled with digoxigenin and an isotopic riboprobe labeled with [35S]UTP localized prolidase gene expression to fibroblasts and endothelial cells of small vessels in scar tissue. Prolidase mRNA was also prominently expressed in keratinocytes near the basal layer overlying scar tissue. These findings indicate that prolidase may have an important role in wound healing.

Antiepiligrin cicatricial pemphigoid: the first case report from Japan

We describe a Japanese man with antiepiligrin cicatricial pemphigoid and typical clinical features, including ocular involvement. Direct immunofluorescence showed IgG deposition at the basement membrane zone. Indirect immunofluorescence of 1M sodium chloride-split skin showed circulating antibasement membrane zone antibodies of IgG class reactive with the dermal side of the split. Immunoblotting of human epidermal and dermal extracts, as well as a bacterial fusion protein of BP180 NC16a domain, showed no specific reactivity. In contrast, with immunoprecipitation of either culture medium or cell lysate from normal keratinocytes, the patient's serum clearly reacted with the protein epiligrin, a laminin isoform present in the lamina lucida of the human epidermal basement membrane zone. This is the first confirmed case of a Japanese patient with this disease entity.

Staphylococcus aureus infection on cut wounds in the mouse skin: experimental staphylococcal botryomycosis

Staphylococcus aureus cells were inoculated on the cut wounds in the skin of cyclophosphamide-treated mice. Biopsy specimens were taken from three mice at 1, 3, 6, 12, 24, 36, 48 and 60 h after the inoculation and were examined by light and electron microscopies. One hour after the inoculation Staphylococcus aureus cells were seen around the cut wound and deeper into the subcutaneous tissue. By 6 h after the inoculation, Staphylococcus aureus cells formed clusters of bacterial colonies. By 36 h after the inoculation inflammatory cells, mainly polymorphonuclear leukocytes and macrophages, were seen around the clusters. Electron microscopic examination revealed fibril-like structures around the Staphylococcus aureus cells at 1 h. The Staphylococcus aureus cells were enclosed in membrane-like structures at 3 h. The membrane-like structures and the fibril-like structures were positive for Ruthenium red. By 12 h after the inoculation, the membrane-like structures increased in thickness and in electron density. Inflammatory cells were seen around but outside of the membrane-like structures at 24, 36 and 48 h. At 60 h the tissues around the membrane-like structures were degenerated and almost necrotic. These results suggest that Staphylococcus aureus cells may form biofilm in dermal or subcutaneous tissues in a neutropenic condition.

[Variegate porphyria]

Variegate porphyria was reviewed in the epidemiological, clinical and biochemical aspects. Dual porphyrias were also referred to.

Neutrophilic eccrine hidradenitis: report of two cases

BACKGROUND

Neutrophilic eccrine hidradenitis (NEH) is an uncommon, self-limited dermatosis usually attributed to anti-cancer chemotherapy. It is characterized histologically by necrosis of the eccrine gland and neutrophilic infiltrate.

OBSERVATIONS

We saw NEH in a 5-year-old boy with acute lymphoblastic leukemia and a 4-year-old girl with acute monocytic leukemia. NEH developed after the anti-leukemic chemotherapy including high dose cytarabine. The eruption was composed of vesicles, papules, and plaques.

CONCLUSIONS

Histological findings were compatible with those described in the literature. NEH in our two patients could be attributed to high doses of cytarabine.

Allergic granulomatosis (Churg-Strauss) associated with cutaneous manifestations: report of two cases

Allergic granulomatosis (Churg-Strauss) is sometimes associated with cutaneous manifestations. Biopsies of these manifestations are characteristic enough to allow for the diagnosis of this disease through histological examination. Case 1 involved a 34-year-old man who developed a low-grade fever, blood eosinophilia, paralysis of the right oculomotor nerve, and a polymorphic eruption. In addition, he suffered from preceding asthma and paresthesia of the legs and eventually developed heart failure. The histological examination of a biopsy taken from a hemorrhagic bulla showed a dense perivascular infiltration of eosinophils in the upper dermis and basophilic degeneration of collagen fibers. Case 2 involved a 41-year-old man who was afflicted with urticarial erythemas, livedoid erythemas, preceding asthma, and blood eosinophilia. During the course of his illness, he also developed bilateral peroneal nerve paralysis and two small erythemato-bullous lesions. The histological examination of a urticarial lesion revealed an abundant eosinophil perivascular infiltration; examination of a nodule revealed basophilic degeneration with a granulomatous reaction. Clinical and laboratory studies strongly suggested the diagnosis of allergic granulomatosis in both of these cases. The diagnosis was also supported by a histological examination of the skin lesions.