Luminal Epithelial Surface Research Articles

Differentiation antigens expressed by epithelial cells in the lactating breast are also detectable in breast cancers.

Two monoclonal antibodies, 3.14.A3 and 1.10.F3, raised against a delipidated preparation of the human milk fat globule and characterized as epithelium-specific (Taylor-papadimitriou et al., 1981) were assayed histologically, by an indirect immunoperoxidase technique, against formalin-fixed, paraffin-embedded, normal and tumour tissue sections, in order to establish their in vivo specificity. Both antibodies bound to less than 10% of the alveoli and ducts in the resting breast, but bound to all areas of alveoli, ducts and secretion in the lactating breast. Binding was to the luminal surface of the alveolar and ductal epithelium. Antibody 3.14.A3 showed positive reactions with each of 20 primary breast carcinomas tested, and with metastatic lesions in lymph nodes from six of these. Antibody 1.10.F3 also reacted with most of the primary carcinomas but not with those of the mucoid type nor with metastatic lesions in lymph nodes. When tested against a variety of normal tissues, 1.10.F3 bound only to the luminal epithelial surface of classically defined exocrine glands, to their associated ducts and to the collecting tubules of kidney and bronchioles of the lung. 3.14.A3 showed a similar pattern of binding to 1.10.F3 but also bound to sweat glands, the alveolar epithelium of lung and the luminal epithelium of the ductuli efferentes of the epididymis. The only tumours, other than breast, showing a positive reaction with the antibodies were adenocarcinomas of the lung, uterus and ovary.

Trophoblastic and uterine luminal epithelial surfaces at the time of blastocyst adhesion in the rat.

Fixed uteri from rats on the afternoon of day 6 of pregnancy were split to expose the implantation chambers, their enclosed blastocysts, and the imprints of the blastocyst on the adjacent epithelium of the chamber. Some of the implantation chambers were prepared for scanning electron microscopy; other chambers were treated with colloidal iron hydroxide, with cationized ferritin, or with the tannic acid method, and subsequently were prepared for transmission electron microscopy. In this manner, the disposition of the surface-coat markers on the surface of the blastocysts, surface of the uterus within the chamber, and the surface of the uterus that had been apposed to a blastocyst were compared. Despite the pronounced morphological differences between the microvilli of the uterine luminal epithelium in the imprint and those in the rest of the chamber, the binding of the markers was remarkably similar. No evidence of removal of surface coat could be found in that area of the uterus in contact with the blastocyst. In addition, in two instances in the cationized ferritin-treated material, and in another instance in tannic acid-stained material, regions of the apparently adhering trophoblastic cell membranes and uterine cell membranes had abundant coat materials and, possibly, even secretory materials interposed. When blastocyst-sized glass beads were introduced into uteri from animals made pseudopregnant or unilaterally pregnant, the beads failed to elicit a decidual response and made an imprint that did not resemble the imprint of a blastocyst in an implantation chamber. It was concluded that, at least in the initial stages of adhesion, the blastocyst does not bring about a physical removal of the demonstrable aspects of the surface coat of the uterus. It was concluded further, that glass beads are not a suitable object for mimicking a blastocyst in the rat uterus.

Varying effects of an IUD on decidualization in mice

Chronically implanted IUDs consisting of silk suture threads induced decidualization in regions of the uterus remote from the suture site in ovariectomized mice treated with a regimen of progesterone and oestrogen which sensitizes the uterus to a decidual stimulus. In these conditions the IUDs did not inhibit decidualization induced by instilled oil, although they did so in pregnant animals of the same strain. Varying the dose of progesterone and oestrogen did not produce conditions in which IUD's inhibited oil-induced decidualization in ovariectomized mice and progesterone treatment did not prevent IUDs inhibiting decidualization in pregnant animals. However, when ovariectomized mice, sensitized as before, were primed repeatedly with oestrogen to simulate continuing oestrous cycles after IUD insertion, the IUD's inhibited oil-induced decidualization. This involved the premature loss of instilled oil from the uterine lumen and was associated with heavy infiltration of leucocytes into the luminal epithelium. Numbers of leucocytes free in the uterine lumen did not appear to be critical. It appears that contact between the oil and the luminal epithelial surface must be sustained for some length of time to induce a decidual reaction; brief contact is not sufficient to trigger the response.

Influence of the trophoblast upon differentiation of the uterine epithelium during implantation in the mouse.

SUMMARY During the preparation of the uterus for implantation of blastocysts the luminal surface of the epithelial cells undergoes a characteristic differentiation. In non-pregnant animals this can be induced by progesterone and oestrogen, but in pregnant animals the basic hormonal control is augmented by a local effect of the blastocyst. This has been demonstrated by examining the uteri of animals made unilaterally pregnant. The differentiation of the luminal epithelial surface of the fertile horn was in advance of that in the sterile horn. The injection of oil into one horn of the uterus of pseudopregnant animals also accelerated the change in the luminal surface of the injected horn. It is suggested that contact with the cell membrane of the trophoblast influences differentiation of the uterine epithelium and that oil is able to mimic this contact reaction.

Morphological and Biochemical Studies on Absorption and Secretion in the Alimentary Tract of Fasciola hepatica L.

The intestinal epithelium of the liver fluke Fasciola hepatica L. was studied with light and electron microscopes. Absorption experiments were performed with ferritin and radioactive amino acids as tracers. Further experiments were carried out on the lytic effect on gelatin of fluid from the gut. The luminal epithelial surface is provided with numerous microvilli. In the cytoplasm of the cells mitochondria occur in rows parallel to lamellae of a rough-surfaced endoplasmic reticulum. The epithelium consists of cells in nonsecretory and secretory phases. In the secretory phase dense granules occur in the apical parts of the cells. In these cells the organelles show degenerative alterations. No absorption of ferritin (a high molecular weight compound) was detected. A rapid uptake in the intestinal epithelium of radioactivity from labeled amino acids (low molecular weight compounds) was found. Extraintestinal digestion of gelatin was observed. Studies of the gut of Fasciola hepatica have led to the idea that the epithelium has absorptive and secretory functions. The absorptive properties of the intestinal epithelium of the fluke have been studied or discussed by Sommer (1880), Miiller (1923), Stephenson (1947), Gresson and Threadgold (1959), and Dawes (1962) and an absorptive function has been assumed. Supporting this view Pantelouris and Gresson (1959) demonstrated uptake of radioactive iron (Fe59). A lytic effect mainly on proteins and presumably enzymatic in nature has been found to be caused by the intestinal epithelium (Stephenson, 1947). Extracellular digestion in the liver fluke has been reported (Miiller, 1923; Reznik, 1963; Dawes, 1963). Miiller (1923) and Dawes (1962) have presented morphological signs of secretion. In order further to elucidate the absorptive and secretory function of the intestinal epithelium of the liver fluke we have performed a combined study using methods from light and electron microscopy, radioautography, and biochemistry. Received for publication 8 September 1964. * Supported by a grant from Jordbrukets forskningsrad, Stockholm. MATERIALS AND METHODS Adult liver flukes were taken alive from bile ducts of beef livers and washed in Hedon-Fleig's solution at pH 8 (cf Dawes, 1954). All experiments with living flukes were performed at 38 C. For the morphological study small pieces (1 mm3 or less) from different parts of flukes were fixed in buffered osmium tetroxide for 24 hr, dehydrated, embedded in Epon (Luft, 1961), and sectioned. For light microscopy 1-,u-thick sections were mounted on slides and stained with buffered toluidine blue (Bjbrkman, 1962). For electron microscopy thin sections were picked up on unoated copper grids, stained with uranyl acetate, and examined in a Siemens Elmiskop I at 60 kv. For the study of the absorption of high molecular weight compounds flukes were incubated in Hedon-Fleig's solution containing 2% (w/v) twice recrystallized ferritin from horse spleen (Mann Research Lab., N. Y.) for 0.5 to 3 hr. The experiments were performed with 1 ml fluid per fluke. Controls were run in plain Hedon-Fleig's solution. Immediately after treatment pieces from the middle part of the gut were processed for electron microscopy as described above. For the study of the absorption of low molecular weight compounds living flukes were incubated in Hedon-Fleig's solution containing one radioactive amino acid. The following amino acids were employed: DL-leucine-2-C, 3.49 mc/mM (Calbiochem); L-methionine-S3, 119.2 mc/mM (The Radiochem. Center, Amersham); DL-phenylalanine3-C1, 4.23 mc/mM (NENC); and DL-tryptophane-