scholarly journals Distribution of fibroblast surface antigen in the developing chick embryo.

1975 ◽  
Vol 142 (1) ◽  
pp. 41-49 ◽  
Author(s):  
E Linder ◽  
A Vaheri ◽  
E Ruoslahti ◽  
J Wartiovaara

Fibroblast surface (SE) antigen is present in fibrillar surface structures of cultured normal fibroblasts, shed to the extracellular medium, and is also found in circulation (serum and plasma). Malignant fibroblasts (transformed by viruses) do not express SF antigen on the cell surface. In this study the in vivo differentiation and distribution of SF antigen has been investigated in the developing chick embryo using cryostat sections and immunofluorescence. The major findings were: (a) SF antigen was detectable in the loose connective tissue of very early (2-to 3-day old) embryos. (b) Condensation of SF antigen was seen in various boundary membranes such as the glomerular and tubular basement membranes of the kidney, the boundary membranes of the notochord, yolk sac, and vitelline membranes and liver sinusoids. (c) SF antigen was found to be cell-type specific. It was seen as a fibrillar network in the loose connective tissue of different organs but not in the parenchymal cells. It was not found in muscle cells at any stage of development. (d) The antigen was present in the undifferentiated mesenchymal cells of the kidney; but not found after their development into epithelial cells of the secretory tubules. (e) Both in vivo and in fibroblast cultures SF antigen was distributed as a fibrillar network. These data indicate that SF antigen is a "differentiation antigen" restricted to certain cells of mesenchymal origin and character, and that is accumulates in the connective tissue during embryogenesis.

10.12737/7361 ◽  
2014 ◽  
Vol 8 (1) ◽  
pp. 0-0 ◽  
Author(s):  
Тельцов ◽  
L. Teltsov ◽  
Добрынина ◽  
I. Dobrynina ◽  
Музыка ◽  
...  

These studies are conducted on 36 human embroys and foetus. Four stages are marked out in the development of connective tissue of the duodenum: 1) mesenchymal stage (28-35 the day of the embryo); 2) the stage of loose embryonic connective tissue (35 days - 3.5 months of foetus); 3) the stage of formation of the definitive loose connective tissue (3,5-6,5 months of the fetus); 4) the stage of initial definitive development (6,5 months before birth of the fetus). Each stage is characterized by a specific set of cellular differens, chemical composition of polysaccarides of cells of connective tissue and intercellular substance. On mesenchymal stage of development, the cells and intercellular substance CHIC-positive substances – contain glycogen and proteoglycans that give metachromasia, stained with alcian blue on Shubitch, Hale, but CHIC are negative. At the stage of loose connective tissue in mesenchymal cells, the reduction of glycogen and accumulation of glycosaminoglycans are identified. Glycogen, hyaluronic acid and precursors sulfated groups glycosaminogly-cans are detected in fibroblasts, endothelium of capillaries, in primary blood cells, in macrophages. At the stage of formation of loose connective tissue, there is the accumulation of TIME – amelanotic compounds (proteoglycans) in the cells and in the intercellular substance. Identification of them showed that the precursors of sulfated glycosaminoglycans and chondroitin sulfates (HSC) type C are identified. The intensity of the response to glycogen decreases. In the initial definitive development in the cytoplasm of fibroblasts – there is moderate staining on Hale-positive substances, poor color on Shubich and toluidine blue. In plasmablastics and in B-lymphocytes, the glycogen and glycosaminoglycans types of hyaluronic acid are identified. In the cytoplasm of mast cells, the substances such as hyaluronic acid, HSH type and unfinished synthesis heparina are identified.


1984 ◽  
Vol 99 (3) ◽  
pp. 1173-1178 ◽  
Author(s):  
R Adler ◽  
J D Lindsey ◽  
C L Elsner

We report here that cells present in embryonic chick retinal monolayer cultures express differentiated properties characteristic of chick cones developing in vivo. Cell suspensions from 8-d chick embryo retina (a stage when photoreceptor differentiation has not yet started) were cultured for up to 7 d in low density, glial-free monolayers. Under these conditions, monopolar cells represent approximately 40% of the total number of process-bearing neurons. After 6 d in vitro, most of these monopolar cells showed morphological features reminiscent of developing chick cones. These features could be detected with phase-contrast microscopy, lectin cytochemistry, and transmission and scanning electron microscopy. Characteristic cone traits expressed by cultured monopolar cells included the following: (a) a highly polarized organization; (b) a single, short, usually unbranched neurite; (c) the polarized position of the nucleus close to the origin of the neurite; (d) characteristic cone inner segment features such as abundant free ribosomes, a polarized Golgi apparatus, a cluster of mitochondria distal to the nucleus, a big, membrane-bound, pigment-containing vacuole reminiscent of the "lipid droplet" characteristic of chick cones, and at least in some cases, a well-developed paraboloid; (e) the presence of a complex of apical differentiations including abundant microvilli and in some cases also a cilium-like process; and (f) the staining of the apical region of the cell with peanut lectin, which has been shown to be selective for chick embryo cones (Blanks, J.C., and L.V. Johnson, 1983, J. Comp. Neurol., 221:31-41; and Blanks, J.C., and L.V. Johnson, 1984, Invest. Ophthalmol. Visual Sci., 25:546-557). This pattern of differentiation achieved by 8-d chick retina cells after 6 d in vitro is similar to that shown by 14-d-old chick embryo cones in vivo. Outer segments are not present at this stage of development either in vivo or in vitro. This experimental system is now being used to search for cellular and molecular signals controlling survival and differentiation of cone cells.


1989 ◽  
Vol 261 (1) ◽  
pp. 37-42 ◽  
Author(s):  
B Smedsrød ◽  
M Paulsson ◽  
S Johansson

Laminin antigens are known to be present in the blood of normal individuals. In the present study we have investigated the fate of laminin-related molecules in the circulation. After intravenous injection in rats, the native laminin-nidogen complex, as well as the separated proteins, were rapidly eliminated from the blood (half-lives 2-10 min) by the liver. The large laminin fragments E1 and E8 (Mr 400,000 and 280,000 respectively), which contain the major cell-adhesion-promoting activities of laminin, were also cleared from the blood mainly by the liver, but the rate of uptake was an order of magnitude lower for these fragments than for laminin. This indicates that the uptake of laminin did not occur via cell-adhesion receptors. The endothelial cells of liver were the most important cell type in the uptake of laminin-nidogen complex, nidogen, laminin and fragment E1, whereas the parenchymal cells were responsible for more than 50% of the uptake of E8 in the liver. Studies in vitro with cultured liver endothelial cells and parenchymal cells demonstrated that the ligands were endocytosed and degraded independently of plasma factors. The results reveal that the level of laminin antigens in blood is a very complex parameter. It is not only dependent on the turnover of basement membranes, but also on the degree of degradation of the material released into the blood and on the functional state of the liver, particularly the liver endothelial cells.


1956 ◽  
Vol 2 (4) ◽  
pp. 67-70 ◽  
Author(s):  
F. Wassermann ◽  
L. Kubota

A technique is described which combines silver impregnation and ultrathin sectioning for the electron microscopic demonstration of fibrils in the connective tissue of the chick embryo. The electron micrographs presented in this paper provide evidence for the specificity and completeness of the silver-impregnation technique. It has been shown that, in this particular tissue after fixation in neutral formalin and at the stage of development represented by our material, the argyrophil fibers are embedded in a material which is continuous with the body of the fibroblasts.


Author(s):  
E. J. Kollar

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.


1963 ◽  
Vol 09 (02) ◽  
pp. 291-299 ◽  
Author(s):  
Helge Stalsberg ◽  
Hans Prydz

SummaryThe formation of hemostatic plugs were studied in the chick embryo through in vivo microscopy, in sections of hemostatic plugs and by measurements of primary bleeding time. Thrombocytes were found to be their only cellular constituent. Ability to form adequate hemostatic plugs appeared rather abruptly in embryos of stages 16-17 and coincided with an increase in thrombocyte precursors (stages III and IV).The thrombocytes initially adhere to the cut edge of the vessel. The extension of the hemostatic plug into the vessel lumen is a secondary step in plug development.


1966 ◽  
Vol 123 (2) ◽  
pp. 309-325 ◽  
Author(s):  
K. Marilyn Smart ◽  
Edwin D. Kilbourne

A comparative study was undertaken of the pathogenesis of infection of the allantoic sac of the chick embryo with three influenza viruses of differing virulence, and of the influence of hydrocortisone on the course of infection. Judged on the basis of earlier onset and greater degree of inflammatory response and diminished survival time of infected embryos, Mel. and Lee viruses were markedly more virulent than PR8, despite the earlier appearance of virus in PR8-infected embryos. Interferon appeared first and in greater quantity in the allantoic fluid of Lee-infected embryos and latest with PR8 infection. Thus, there was no correlation of avirulence and better interferon production with the viruses under study in the present system. Furthermore, evidence obtained suggested that Lee virus ("virulent") was most susceptible to interferon action, and also that viral synthesis in the chorioallantoic membrane with PR8 ("avirulent") persisted after the appearance of interferon. The injection of hydrocortisone within 2 hr of the initiation of infection delayed the synthesis of all three viruses; had no significant effect upon the inflammatory response; and transiently inhibited the synthesis of interferon, while prolonging the survival of Lee- and Mel.-infected embryos. Late administration of hydrocortisone suppresses both the inflammatory response and the production of interferon. Only in the case of Lee virus infection did hydrocortisone administration lead to augmentation of final yields of virus with the low infection multiplicity employed in the present experiments. It is postulated that Lee virus is a better inducer of interferon because its infectivity in vivo is more rapidly inactivated. As a consequence synthesis of Lee virus is more under the control of endogenous interferon than is the case with PR8 or Mel. virus. Therefore, inhibition of interferon synthesis with hydrocortisone has a greater influence on final yields of Lee virus.


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