Selective planting of cationized,haptenized ovalbumin on the rat tubular basement membrane

We developed an experimental protocol for planting exogenous antigens with different molecular weights and charges on the constituents of the renal tubulointerstitium. The cationized antigens were injected selectively into the left renal arteries of Wistar rats. Antigen localization was documented by immunohistochemistry on frozen sections. Cationized bovine serum albumin (BSA; 68 kDa, isoelectric point =9.5) localized almost exclusively along the glomerular capillary wall. After application of highly cationic polyethyleneimine, cationized BSA given subsequently was found in a linear distribution along the glomerular capillary wall and along the peritubular capillaries. The fate of highly cationized ovalbumin conjugated with trinitrophenol (TNP-OA), subjected to gel filtration to obtain monomers (42 kDa, isoelectric point >10) differed; it was deposited in a linear pattern on the tubular basement membrane (TBM) and Bowman's capsule, and remained up to 36 h after injection. Noncationized, monomeric TNP-OA (42 kDa, isolectnic point =4.6) showed fine granular deposition in the tubular epithelium exclusively. These findings indicate that the barrier of the glomerular BM acts selectively on antigens with different molecular weights. They either settle on the peritubular capillaries, after passing the glomerular, or reach the urinary space, after which they are reabsorbed by the tubular epithelial cells to reach the TBM.     

Localization of T lymphocytes and macrophages expressing IL-1, IL-2 receptor,IL-6 and TNF in human aortic intima. Role of cell-mediated immunity in human atherogenesis

Recent observations have demonstrated the presence of activated T lymphocytes and macrophages in human atherosclerotic lesions. Cells found within these lesions produce cytokines that alter vascular homeostasis in a manner that promotes atherogenesis. To elucidate the role of these immunocompetent cells in human atherosclerosis, the localization of various cytokines with an analysis of immunophenotypic features of the cellular infiltrates was studied in normal aortas from children; and in later phases of the disease (including fatty streaks and fibrous or atheromatous plaques). Semi-quantitative analysis of cytokine-expressing cells was also investigated with serial sectioning. In 4 of 9 young subjects, the grossly normal aorta contained relatively cell-rich areas which were located preferentially around the ostia of intercostal arteries and were composed of isolated or layered T lymphocytes and macrophages. In these prelesional areas, interleukin-1 (IL-1), IL-2 receptor (IL-2R) and tumour necrosis factor (TNF) were detected in the cytoplasm of the infiltrating cells, whereas no detectable reactivity was noted for IL-2, IL-6, interferon-γ (IFN-γ) or lymphotoxin (LT). In fatty streaks and full-grown atheromas including “cap” and “shoulder” regions, various numbers of T lymphocytes, macrophages and macrophage foam cells were present. In these lesion areas, especially where the cellular infiltrates were numerous, macrophage foam cells and smooth muscle cells expressed not only IL-1 and TNF but also IL-6. The ratio of IL-2R positive cells showed a tendency to decrease with advance of the disease process. Electron-microscopic examination of lesion areas demonstrated ultrastructural aspects of the cognate cellto-cell interaction, as shown by the direct apposition of lymphocytes to macrophages or macrophage foam cells. These results suggest that a specific in situ, cell mediated hypersensitivity plays a pivotal role in the nascent as well as the progression stages of human atherosclerosis.     

The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization

Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation.     

Catecholaminergic neurites in senile plaques in prefrontal cortex of aged nonhuman primates

Immunocytochemical studies, using a polyclonal antibody directed against tyrosine hydroxylase, identified catecholaminergic axons in prefrontal cortex of young and aged nonhuman primates. Aged monkeys, who showed cortical senile plaques in silver stains, had swollen tyrosine hydroxylase-immunoreactive axons in neocortex. Some of these abnormal processes were associated with deposits of amyloid (visualized by thioflavin-T fluorescence) and were similar in appearance to neurites demonstrated by silver impregnation methods. This study provides evidence for structural abnormalities in catecholaminergic axons/nerve terminals in the neocortices of aged primates.     

Chromosome 1q terminal deletion resulting fromde novo translocation with an acrocentric chromosome

Summary Distal deletion of chromosome 1q has been reported in nearly 30 patients, all being associated with a deletion ranging from the 1q42 or q43 band to 1qter region. Here, we describe a girl with 1q terminal deletion resulting from an unbalancedde novo translocation t(1;D or G)(q44; p11), as revealed by the presence of a satellited feature and an NOR-stained region at the tip of 1q. We suggest that most of the phenotypic abnormalities seen in patients with 1q distal deletion are attributable to the monosomy for band 1q44.     

Redistribution of fibroblasts and macrophages as micrometastases develop into established liver metastases

Fibroblastic tissue is an important component of malignant tumors, involved in the establishment of metastatic foci from micrometastases, and thought to prevent invasion of metastatic tumor cells into surrounding tissue. However, experimental models of fibrosis during the growth of micrometastasis into established metastases were not previously available. In the present paper, we performed immunohistochemical studies on experimental hepatic metastasis with colon 38 mouse colon carcinoma cells injected into syngeneic C57BL/6 mice. Early and late stages of metastatic nodules were examined for the distribution of endothelial cells, fibroblasts, and macrophages by the use of markers of these cells. One week after intrasplenic injection of colon 38 cells, micrometastases mainly appeared in the region of sinusoids accompanied with invasion of F4/80-positive Kupffer cells. Transitional metastases can be defined based on the histological appearance and intensive infiltration of both macrophages and fibroblasts. These transitional metastases were connected by protrusions of fibroblast-rich tissues co-localized with collagen-rich matrix and CD31-positive cells. This protrusion preceded fibrosis formation characteristics to established metastases associated with angiogenesis and segregation of tumor cells from host cells. Three stages can thus be classified during the development of hepatic metastasis in this syngeneic experimental system: micrometastasis, transitional metastasis, and established metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.     

Mouse Colon Carcinoma Cells Established for High Incidence of Experimental Hepatic Metastasis Exhibit Accelerated and Anchorage-Independent Growth

Highly metastatic variants of mouse colon 38 colon carcinoma cells were established by repeated selection in vivo for liver metastasis and designated as SL4 cells. The SL4 cells formed colonies in the liver of 100% of syngenic mice when injected intrasplenically, while the incidence of liver metastasis was 27% of mice injected with parental cells. The weight of livers, which is an indicator of experimental hepatic metastasis formation, was significantly higher after intrasplenic injection and subsequent splenoctomy with SL4 cells than colon 38 cells. The incidence of hepatic metastasis after intracecal injection of SL4 cells was significantly higher than that of colon 38 cells. The SL4 cells were tested in vitro for their properties. Differences were not detected in the motility and invasive behavior between colon 38 cells and SL4 cells. SL4 cells showed a higher proliferation rate than colon 38 cells under adherent conditions. SL4 cells maintained a capacity to proliferate under non-adherent conditions whereas parental cells did not. SL4 cells should be a useful tool to study the mechanism of hepatic metastasis of colon carcinoma cells and to develop methods to prevent hepatic metastasis.     

PLASMA CELL GRANULOMA OF THE LUNG WITH EXTRAPULMONAL EXTENSION

A rare case of plasma cell granuloma of the lung in a 5-year-old girl showing extrapulmonal extension to the adjoining thoracic wall was reported. Intrapulmonal and thoracic wall granulomas revealed the same histopathologic features; proliferation of plasma cells and fibrous connective tissue. Although slightly atypical plasma cells were observed among many mature ones, immunohistochemical examination revealed polyclonal proliferation, confirming their inflammatory nature. Cellular components of fibrous connective tissue were identified as fibroblastic cells and myofibroblasts by electron microscopy. The present case and literature suggested the importance of the fact that "infiltrative" plasma cell granuloma had a tendency to occur in children. ACTA PATHOL. JPN. 35: 933–944, 1985.