Detection of lysyl oxidase gene expression in rat skin during wound healing.

Lysyl oxidase (LOX) initiates the crosslinking of the lysine-derived aldehyde and plays an essential role in maturation of collagen, for example in wound healing. Although the activity of this enzyme has been examined in various disorders, and a further intriguing aspect of the relationship between LOX and tumorigenesis has recently emerged, its gene expression pattern in tissues is still unknown. We examined LOX gene expression during wound healing in rat skin. In addition, type III collagen gene expression was studied to determine the formation of fibrils. The LOX mRNA level reached a peak by day 3 after injury, which was earlier than that of type III collagen, and continued at a high level until day 22. The type III collagen mRNA level began to rise from day 3 and had increased intensely by day 22. In situ hybridization revealed grains corresponding to LOX mRNA in the fibroblasts of the granulomatous tissue. These results suggest that LOX is produced before collagen synthesis in preparation for crosslinking in the early phase of wound healing.

Increased expression of lysyl oxidase in skin with scleroderma.

Lysyl oxidase initiates cross-linkage of collagen and elastin by catalysing the formation of a lysine-derived aldehyde. In order to study cross-linking in scleroderma, we used monoclonal antibodies to lysyl oxidase to determine the localization of this enzyme in systemic and localized scleroderma, and compared the distributions obtained with that in normal skin. Using an indirect immunofluorescent antibody method and an avidin-biotinylated enzyme complex method, 11 cases of diffuse type of systemic scleroderma and seven cases of localized scleroderma were studied. In the oedematous stage of systemic scleroderma, intracellular and extracellular lysyl oxidase were remarkably increased in the dermis, particularly in groups around blood vessels. In the sclerotic stage of systemic scleroderma, lysyl oxidase was detected intracellularly in fibroblasts and extracellularly among collagen bundles between the lower dermis and the subcutaneous fat tissue. In localized scleroderma, a marked increase in lysyl oxidase was observed in mononuclear cells and fibroblasts near blood vessels in the lower dermis and in the subcutaneous fat tissue, in addition to the extracellular deposits between collagen bundles. The increase in lysyl oxidase in localized scleroderma was much more common than in the oedematous stage of systemic scleroderma. These findings indicated that intracellular and extracellular expression of lysyl oxidase expression was greater in sclerodermatous skin than in normal skin.

Immunohistochemical localization of lysyl oxidase in normal human skin.

Lysyl oxidase (EC 1.4.3.13), a copper-dependent enzyme which catalyses the formation of aldehyde cross-links, and acts primarily on collagen and elastin, is known to be increased during wound healing and in fibrotic disorders including liver cirrhosis and atherosclerosis, and to be decreased in some hereditary connective tissue diseases and in malignant cell lines. A recent study showed that lysyl oxidase might possess tumour suppressor activity as an antioncogene for ras. Little is known about the localization of this enzyme in human skin. In this study, we determined immunohistochemically the localization of lysyl oxidase in normal skin of young and elderly subjects obtained from sun-exposed and unexposed regions of the body. All skin samples tested had similar distributions of lysyl oxidase. The enzyme was present both extracellularly and intracellularly. Extracellularly, a few granular aggregates of immunoreactants were observed along collagen and elastic fibres. These granules were more common in the adventitial portion of the dermis than in the reticular portion. Of all sun-exposed and unexposed regions studied, the skin of the face displayed the greatest amount of extracellular immunoreactants. Immunopositive granules were observed intracellularly in fibroblasts, vascular endothelial cells, sweat glands, sebaceous glands, arrector pili muscles and some keratinocytes. These findings provide evidence that, as suggested in recent reports, lysyl oxidase may have a variety of intracellular functions.

Recurrent generalized lichen nitidus associated with amenorrhea.

A case of recurrent generalized lichen nitidus is reported. The eruptions developed in the proliferative phase of the menstrual cycle, but there has been a marked improvement after administration of estrogen and progesterone for the treatment of amenorrhea. Hormonal factors may play a role in the development of lichenoid tissue reaction in the lesions of this disease.

Chédiak-Higashi syndrome: report of a case and review of the Japanese literature.

We report the case of a Japanese female infant with Chédiak-Higashi syndrome born to consanguineous parents. At birth she had fair skin but, when she was three months old, marked hyperpigmentation of the sun-exposed skin areas developed. Microscopic examination of blood and electron microscopic examination confirmed the diagnosis. She enjoyed good health until she was two years old when she had pneumonia with marked hepatosplenomegaly. It is important for dermatologists and pediatricians to be aware of the skin manifestations of this disease because hyperpigmentation after sun exposure may be a characteristic, initial feature of this condition.

Immunohistochemical localization of type I, III, IV, V, and VI collagens and laminin in neurofibroma and neurofibrosarcoma.

By using antibodies to type I, III, IV, V, and VI collagens and laminin, we examined the localization of interstitial collagens and basement membrane components with indirect immunofluorescence and immunoelectron microscopy (IEM). Furthermore, the morphological changes of these collagens in malignant transformation were investigated. In neurofibroma, IEM showed type I, III, and V collagens to be present diffusely on cross-striated collagen fibrils, whereas type VI collagen was present between the fibrils. Type IV collagen and laminin were observed to surround tumor cells. In neurofibrosarcoma, tumor collagen bundles that reacted with antibodies to type I, III, V, and VI collagens were irregularly arranged. Immunofluorescent deposits that reacted with anti-type IV collagen and anti-laminin antibodies were decreased in number, showing a thin and sparse arrangement.

Alteration of cartilagenous proteoglycan in psoriasis.

Articular tissue was obtained at surgery for a femoral neck fracture in a patient with psoriasis without arthritis. The proteoglycan of the cartilage of the sample was analysed biochemically. Normal cartilage is known to produce two types of proteoglycan monomers (fast- and slow-sedimenting groups), which are distinguishable by density-gradient ultracentrifugation. In the psoriatic cartilage analysed in the present study, it was shown that the former group was absent and only the latter group remained.

Primary cutaneous adenoid cystic carcinoma: ultrastructural study and immunolocalization of types I, III, IV, V collagens and laminin.

A primary adenoid cystic carcinoma of the skin is reported. Light microscopy revealed pseudocysts. PAS-positive basement membrane and true glandular lumen, which in aggregates are specific for adenoid cystic carcinoma. Perineural invasion was also observed. Ultrastructural examinations revealed three types of cystic spaces; pseudocysts, true glandular lumens and intercellular spaces. Enzyme histochemical examinations showed positive reactions for eccrine enzymes, including phosphorylase and succinic dehydrogenase and negative for apocrine enzymes. Immunolocalization of collagens and laminin revealed that basement membranes of the pseudocysts involve Type V collagen as well as Type IV collagen and laminin.

Possible formation of cutaneous amyloid from degenerative collagen fibers. Ultrastructural collagen changes and the immunoreactivity of cutaneous amyloidosis employing anti-type I, III, IV, V collagen antibodies.

The origins of primary cutaneous amyloid have been investigated and several possibilities are proposed. We investigated here several cases by electron microscopy and found in all cases characteristic filamentous changes which were identical with amyloid structures in the collagen bundles. These observations suggested a possible pathway of cutaneous amyloid formation from degenerative collagen fibers. Further studies were performed using immunoelectron microscopical and immunohistochemical methods employing a panel of anti-collagen antibodies to examine the reactivity of amyloid to them. Our results were much more suggestive of the collagen origin of this kind of amyloid.

Farber's lipogranulomatosis in siblings: light and electron microscopic studies.

Two cases of Farber's lipogranulomatosis in siblings are reported. The clinical features included contractures of the limbs with swelling of the joints and subcutaneous nodules and erythematous infiltrated plaques. On histology there were many large foam cells in the dermis, and electron microscopy showed numerous large cells with round cytoplasmic lamellar and microtubular bodies.

The subbasement membrane distribution of type IV collagen in normal human skin.

Samples of normal human skin were obtained from 48 sites in 26 subjects ranging in age from 2 to 85 years. The samples were examined by indirect immunofluorescence and immunoelectron microscopy using anti-human type IV collagen antibodies produced by immunizing rabbits with type IV collagen extracted from human placenta. Fluorescence was observed as granular or fine fibrous patterns, not only in the basement membrane at the dermo-epidermal junction, around the vessels, and the accessory organs of the skin, but also in the dermal regions in the vicinity of the basement membranes. This suggests the presence of type IV collagen in the dermis deep to the basement membrane. Ultrastructurally, the extrabasal lamina distribution of type IV collagen was noted as a partial distribution around the fibroblasts that existed close to the basal lamina. These findings are considered to be important in examining the function of this collagen in the dermis and the dynamics and metabolism of the basement membrane under normal and abnormal conditions.

Nevus lipomatosus cutaneus superficialis of the scalp.

A 12-year-old boy with nevus lipomatosus cutaneus superficialis of the scalp is described. Asymptomatic plaques made up of varying sized aggregates of elastic soft papules were observed on the occipital region. Histologic examination of a biopsy specimen revealed ectopic fat tissue in the dermis. Two types of nevus lipomatosus cutaneus superficialis can be differentiated clinically. The classic types, with multiple lesions in a zonal distribution, occur most often on the lumbar region, buttocks, and thigh. The other types, which involve a solitary papule or nodule, have no favored location. This is the first report of multiple lesions in a zonal distribution occurring characteristically on the scalp.

Immunohistochemical localization of type V collagen in normal human skin.

Tissue distribution of type V collagen in normal human skin was studied using an indirect immunofluorescent technique to determine whether type V collagen is present in the interstitium or in the basement membrane. Type V collagen was isolated from the human placenta by pepsin digestion and was purified with fractioning salt precipitations. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that type V collagen contained alpha 1(V) and alpha 2(V) chains, but not the alpha 3(V) chain. Specificity of the rabbit antibodies to type V collagen was assessed using enzyme-linked immunosorbent assay (ELISA) and an immunoblotting method. Antibodies showed no cross-reactivity to other collagens, laminin, and fibronectin. With an indirect immunofluorescent technique, type V collagen was found to be widely distributed throughout the dermis. Intense fluorescent staining was noted in the papillary dermis and adnexal dermis surrounding hair follicles and eccrine glands. The basement membrane of the dermoepidermal junction, skin appendages, and capillaries was not stained. By indirect immunoperoxidase double staining, type V collagen was not found to be deposited on type IV collagen present in the basement membrane. Immunoelectron microscopic studies showed that type V collagen was not located in the basal lamina. These results suggest that type V collagen is distributed in the interstitium, but not in the basement membrane of normal human skin.

Immunofluorescent localization of type I and III collagens in normal human skin with polyclonal and monoclonal antibodies.

Anti-type I and type III collagen polyclonal antibodies and anti-type III collagen monoclonal antibodies were produced using type I and type III collagen extracted from the human placenta. An indirect immunofluorescence technique using these antibodies showed the same distribution of type III as well as type I collagen in the entire dermis of the normal human skin in nearly identical patterns. Previous immunofluorescent study indicated that type III collagen is present predominantly in the papillary dermis. However, our observation that monoclonal antibody recognizing the helical portion of type III collagen reacted with the entire thickness of the dermis which suggested the presence of type I and III collagen in close proximity in the whole thickness of normal human dermis.