IMMUNOHISTOCHEMICAL LOCALIZATION OF TYPE I, II, III, AND IV COLLAGENS IN THE LUNG

Type specific rabbit antibodies to bovine type I, 11, 111, and IV (basement membrane) collagens showing no cross-reaction with other types of collagen were prepared by cross-adsorption and diethylamiuoethyl-cellulose romatography. The antibodies to bovine type I and I11 collagens showed a high cross-reaction with the corresponding human collagens, but those to type I1 and IV collagens did moderate and no cross-reactions with human type I1 and IV collagens, respectively. By using these antibodies, tissue distribution of various types of collagen in normal bovine lung was examined by indirect immunofluorescence microscopy. Both type I and I11 collagens were found to distribute widely in the interstitium of bronchial tree, bronchial
lamina propria and of interlobules as well as alveolar nipples and adventitia of pulmonary arteries. Type I1 collagen was located only in bronchial cartilage. The tissues mainly stained for type 11 collagen were the alveolar interstitium (also stained faintly for type I collagen) and the intima and media of the arteries. Type IV collagen was located in a membranous fashion in alveolar septa and bronchial smooth muscles and subepithelial layers as well as capillaries and the intima and media of arteries. ACTA PATHOL. JPN. 31: 601–610, 1981.     

A Case of Pneumocytoma (So-Called Sclerosing Hemangioma) With Lymph Node Metastasis

A case of "sclerosing hemangionia" (pneumocytoma) of the lungwith lymph node metastasis is reported. A 22-year-old Japaneseman was found to have a well-defined round lesion in the rightlung (S⁷), which increased in size slightly during a 2-yearfollow-up period. He underwent right lower lobectomy with a preoperative diagnosisof a benign lung tumor. The pulmonary tumor revealed histologicalfeatures characteristic of "sclerosing hemangioma" of the lung,in addition to which there were many large polygonal foamy cells,forming tubular or papillary structures. These cells were foundby electron microscopy to contain numerous cytoplasmic lamellarbodies and showed a positive reaction with anti-surfactant apoproteinantibody immunohistochemically. Therefore, they were consideredto be cells differentiating toward type II pneumocytes. Reviewof 21 typical "sclerosing hemangionia" disclosed a few or somesuch foamy cells in 10 cases. A single hilar lymph node wasthe site of microscopic metastases, which consisted of "largeclear foamy cells" and smaller polygonal or round cells withslightly eosinophilic cytoplasm, both of which were componentsof the pulmonary "sclerosing hemangioma" This case supportsthe theory that "sclerosing hemangioma" is a neoplasm of typeII pneumocyte lineage. Although it is said to be benign, rarecases apparently show metastatic potential.     

The Th2 cytokine,interleukin‐4, abrogates the cohesion of normal stratum corneum in mice: implications for pathogenesis of atopic dermatitis

There is mounting evidence that Th2 cytokines adversely affect skin barrier functions and contribute to the pathogenesis of atopic dermatitis (AD). AD is also characterized by abnormal cohesion in the stratum corneum (SC). However, the contribution of Th2 cytokines to this abnormality remains unknown. This study examined the effects of IL‐4, a prototypic Th2 cytokine, on the cohesion of the SC. Structural and physiological assessments revealed that repeated intradermal injections of IL‐4 compromised the cohesion of the SC of normal hairless mice. Two potential mechanisms were explored to account for the altered cohesion. First, IL‐4 decreased the amount of corneodesmosomes and down‐regulated the expression of desmoglein 1, but not of corneodesmosin (CDSN) or loricrin expression, in murine skin and in cultured human keratinocytes (KC). IL‐4 did not affect the skin surface pH, and in situ zymography revealed no net change in total serine protease activity in the IL‐4‐treated SC. Yet, IL‐4 enhanced expression of kallikrein (KLK)7, while simultaneously down‐regulating KLK5 and KLK14. Finally, IL‐4 did not alter the expression of the lympho‐epithelial Kazal‐type inhibitor (LEKTI) in KC. This study suggests that IL‐4 abrogates the cohesion of SC primarily by reducing epidermal differentiation.     

Adrenoleukodystrophy indicated by abnormal electroencephalography

An 8 year old boy with adrenoleukodystrophy and his asymptomatic brother, both with abnormal electro-encephalography as the initial sign of adrenoleukodystrophy, are reported. After suffering from aseptic meningitis caused by Echo virus 30, the first case was suspected of having a complication of meningitis because of persistent abnormal electro-encephalography (i.e. slow wave bursts in the occipital region). This patient was finally diagnosed as having adrenoleukodystrophy because of the increased level of very long chain saturated fatty acids, and typical occipital lesions demonstrated by magnetic resonance imaging and computed tomography. Dietary therapy was tried, but the course was progressive. The brother's electroencephalography was also abnormal and so was diagnosed as having asymptomatic adrenoleukodystrophy because of an increased level of very long chain saturated fatty acids, although brain magnetic resonance imaging was normal. Abnormal electro-encephalography can therefore be an initial sign of adrenoleukodystrophy even if magnetic resonance imaging shows no abnormality in the brain.     

Biophysical properties of protein-free,totally synthetic pulmonary surfactants,ALEC and Exosurf,in comparison with surfactant TA

An artificial pulmonary surfactant prepared from chloroform-methanol extract of bovine pulmonary surfactant (surfactant TA) has been shown to be effective in both the prevention and the treatment of respiratory distress syndrome in premature babies. Recently, two types of protein-free totally synthetic surfactants, artificial lung expanding compound (ALEC) and Exosurf, have been evaluated in clinical trials of surfactant therapy. Artificial lung expanding compound was used initially as a dry powder, but is now prepared as a crystalline suspension in saline at 4°C. In this study we compared the biophysical properties of three different forms of ALEC (dry powder, crystalline suspension at 4°C and 37°C), Exosurf and surfactant TA (Surfacten) using a modified Wilhelmy surface balance and a pulsating bubble surfactometer. Surface activity of a crystalline suspension of ALEC in cold saline was no better than the dry powder of ALEC. Surfactant activity of ALEC was improved by addition of hydrophobic surfactant protein B and C (SP-B, SP-C) which are important constituents of surfactant TA. Surface properties of ALEC in any form and Exosurf were not superior to those of surfactant TA. These results suggest that a surfactant which contains SP-B and SP-C does not necessarily have to be dry or crystalline for an effective exogenous surfactant.