SEM localization of cell-surface-associated fibronectin in the cranium of chick embryos utilizing immunolatex microspheres

Development ◽  
1984 ◽  
Vol 80 (1) ◽  
pp. 175-195
Author(s):  
Stephen Meier ◽  
Christopher Drake

Fibronectin has been localized to basement membranes and cell surfaces with the light microscope by fluorescent staining of thick sections, and with the TEM by immunoperoxidase reaction. However, these methods are limited because it is difficult to appreciate the patterned distribution of fibronectin from sectioned material. We have developed a probe for fibronectin that facilitates its identification with the SEM. Our probe consists of two parts; the first component is a derivatized methacrylate microsphere 90 nm in diameter, linked to purified sheep anti-rabbit IgG. The second component is anti-fibronectin IgG raised in rabbits. Stage-3 to -12 chick embryos were fixed and the ectoderm covering the cranial mesoderm was removed. Embryos were treated with testicular hyaluronidase, exposed to rabbit antifibronectin IgG and finally to sheep anti-rabbit IgG conjugated microspheres. As expected, the basal lamina of surface and neural ectoderm as well as the remaining fibrous ECM were heavily decorated with microspheres, whereas control embryos treated with preimmune serum were beadless. Fibronectin was localized on the cell soma and processes of primary mesenchyme as early as stage 3. In addition, it was possible to decorate to various extents, populations of prosencephalic, mesencephalic, and rhombencephalic cranial neural crest cells. Our studies suggest that fibronectin is present in the cranium of chick embryos at earlier times than heretofore realized, and that fibronectin accumulates in a cranial to caudal gradient that reflects the sequential differentiation of the embryonic axis.

Author(s):  
Yukiko Sugi

In cultured skeletal muscle cells of chick, one intermediate filament protein, vimentin, is primarily formed and then synthesis of desmin follows. Coexistence of vimentin and desmin has been immunocytochemically confirmed in chick embryonic skeletal musclecells. Immunofluorescent localization of vimentin and desmin has been described in developing myocardial cells of hamster. However, initial localization of desmin and vimentin in early embryonic heart has not been reported in detail. By quick-freeze deep-etch method a loose network of intermediate filaments was revealed to exist surrounding myofibrils. In this report, immunocytochemical localization of desmin and vimentin is visualized in early stages of chick embryonic my ocardium.Chick embryos, Hamburger-Hamilton (H-H) stage 8 to hatch, and 1 day old postnatal chicks were used in this study. For immunofluorescence study, each embryo was fixed with 4% paraformaldehyde and embedded in Epon 812. De-epoxinized with sodium methoxide, semithin sections were stained with primary antibodies (rabbit anti-desmin antibody and anti-vimentin antibody)and secondary antibody (RITC conjugated goat-anti rabbit IgG).


Development ◽  
1980 ◽  
Vol 57 (1) ◽  
pp. 71-78
Author(s):  
N. B. Levy ◽  
Ann Andrew ◽  
B. B. Rawdon ◽  
Beverley Kramer

Two- to ten-somite chick embryos were studied in order to ascertain whether, as has been proposed, there exists a ‘ventral neural ridge’ which gives rise to the hypophyseal (Rathke's) pouch. Serial sections and stereo-microscopy were used. The neural ridges arch around the rostral end of the embryo onto the ventral surface of the head, but no evidence was found for their extension to form a ‘ventral neural ridge’ reaching the stomodaeum: in fact a considerable expanse of non-thickened surface ectoderm was seen to separate the ventral portions of the neural ridges from the stomodaeum. The thickening of neural ectoderm which does appear on the ventral surface of the head results from apposition and fusion of the opposite neural ridges flanking the neural plate and thus the tip of the anterior neuropore - the classically accepted mode of closure of the neuropore. These findings are in accord with the generally accepted concept of the origin of thehypophyseal pouch rather than with its derivation from a ‘ventral neural ridge’. No sign of neural crest formation was encountered ventrally; this observation excludes the possibility that endocrine cells of the APUD series could originate from neural crest in this region.


1986 ◽  
Vol 34 (7) ◽  
pp. 847-853 ◽  
Author(s):  
D R Abrahamson

Ultrastructural distribution of laminin within renal glomerular (GBM) and tubular basement membranes (TBM) was investigated using post-embedding immunolocalization with colloidal gold. Rat kidneys were fixed with 4% formaldehyde and embedded at 4 degrees C in Lowicryl K4M medium. Thin sections were then sequentially treated with affinity-purified rabbit anti-laminin IgG and anti-rabbit IgG conjugated to 10 nm diameter colloidal gold. Gold bound specifically to the GBM and TBM with particle densities of 690/micron2 and 731/micron2, respectively. In the GBM, the number of gold particles bound/micron2 of lamina densa greater than lamina rara externa greater than lamina rara interna. Closely similar binding patterns were found when kidneys were fixed with 0.5% glutaraldehyde plus 3% formaldehyde and embedded at 60 degrees C in L.R. White resin, but slightly less gold bound to sections overall than that seen with formaldehyde alone and Lowicryl. Taken together, these results illustrate that anti-laminin IgG, whether applied to fixed sections in vitro or introduced in vivo, bound to the lamina rara interna, lamina densa, and lamina rara externa of the GBM and throughout the TBM.


1976 ◽  
Vol 22 (3) ◽  
pp. 585-596
Author(s):  
H. Fujisawa ◽  
H. Morioka ◽  
K. Watanabe ◽  
H. Nakamura

Ultrastructural studies of thin-sectioned and freeze-cleaved materials were performed on developing retinal tissues of 3- to 9-day-old chick embryos to clarify the junctional structures between neural retinal cells and between neural retinal cells and cells of the pigmented epithelium. Frequency, size and position of gap junctions in developing neural retina are different at each stage of development. In 3-day-old embryos, some cells adhere to each other by gap junctions immediately below the outer limiting membrane of neural retinae. The size and number of gap junctions increase remarkably during 5–6 days of incubation. In this period of development, well developed gap junctions consisting of subcompartments of intramembrane particles are found between cell surfaces at both the outer limiting membrane region and the deeper portion of the neural retina. Gap junctions disappear thereafter, and at 7-5 days of incubation, small gap junctions are predominant between cell surfaces at the outer limiting membrane region, while the frequency of gap junctions in the deeper portion is very low. At 9 days of incubation, gap junctions are rarely found. Typical gap junctions are always found between neural retinal cells and those of the pigmented epithelium in embryos up to 7-5 days of incubation. Tight junctions are not found in the neural retina or between neural retina and pigmented epithelium throughout the stages examined.


1980 ◽  
Vol 85 (3) ◽  
pp. 735-753 ◽  
Author(s):  
W H Reeves ◽  
Y S Kanwar ◽  
M G Farquhar

Glomerular development was studied in the newborn rat kidney by electron microscopy and cytochemistry. Glomerular structure at different developmental stages was related to the permeability properties of its components and to the differentiation of anionic sites in the glomerular basement membrane (GBM) and on endothelial and epithelia cell surfaces. Cationic probes (cationized ferritin, ruthenium red, colloidal iron) were used to determine the time of appearance and distribution of anionic sites, and digestion with specific enzymes (neuraminidase, heparinase, chondroitinases, hyaluronidases) was used to determine their nature. Native (anionic) ferritin was used to investigate glomerular permeability. The main findings were: (a) The first endothelial fenestrae (which appear before the GBM is fully assembled) possess transient, negatively charged diaphragms that bind cationized ferritin and are impermeable to native ferritin. (b). Two types of glycosaminoglycan particles can be identified by staining with ruthenium red. Large (30-nm) granules are seen only in the cleft of the S-shaped body at the time of mesenchymal migration into the renal vesicle. They consist of hyaluronic acid and possibly also chondroitin sulfate. Smaller (10-15-nm) particles are seen in the earliest endothelial and epithelial basement membranes (S-shaped body stage), become concentrated in the laminae rarae after fusion of these two membranes to form the GBM, and contain heparan sulfate. They are assumed to be precursors of the heparan sulfate-rich granules present in the mature GBM. (c) Distinctive sialic acid-rich, and sialic acid-poor plasmalemmal domains have been delineated on both the epithelial and endothelial cell surfaces. (d) The appearance of sialoglycoproteins on the epithelial cell surface concides with the development of foot processes and filtration slits. (e) Initially the GBM is loosely organized and quite permeable to native ferritin ;it becomes increasinly impermeable to ferritin as the lamina densa becomes more compact. (f) The number of endothelial fenestrae and open epithelial slits increases as the GBM matures and becomes organized into an effective barrier to the passage of native ferritin.


1986 ◽  
Vol 103 (6) ◽  
pp. 2489-2498 ◽  
Author(s):  
D R Abrahamson ◽  
E W Perry

Tannic acid in glutaraldehyde fixatives greatly enhanced the visualization of two developmentally and morphologically distinct stages in glomerular basement membrane (GBM) formation in newborn rat kidneys. First, in early stage glomeruli, double basement membranes between endothelial cells and podocytes were present and, in certain areas, appeared to be fusing. Second, in maturing stage glomeruli, elaborate loops and outpockets of basement membrane projected into epithelial, but not endothelial, sides of capillary walls. When Lowicryl thin sections from newborn rat kidneys were sequentially labeled with rabbit anti-laminin IgG and anti-rabbit IgG-colloidal gold, gold bound across the full width of all GBMs, including double basement membranes and outpockets. The same distribution was obtained when sections from rats that received intravenous injections of rabbit anti-laminin IgG 1 h before fixation were labeled directly with anti-rabbit IgG-colloidal gold. When kidneys were fixed 4 d after anti-laminin IgG injection, however, loops beneath the podocytes in maturing glomeruli were usually unlabeled and lengths of unlabeled GBM were interspersed with labeled lengths. In additional experiments, rabbit anti-laminin IgG was intravenously injected into newborn rats and, 4-14 d later, rats were re-injected with sheep anti-laminin IgG. Sections were then doubly labeled with anti-rabbit and anti-sheep IgG coupled to 10 and 5 nm colloidal gold, respectively. Sheep IgG occurred alone in outpockets of maturing glomeruli and also in lengths of GBM flanked by lengths containing rabbit IgG. These results indicate that, after fusion of double basement membranes, new segments of GBM appear beneath developing podocytes and are subsequently spliced into existing GBM. This splicing provides the additional GBM necessary for expanding glomerular capillaries.


1986 ◽  
Vol 163 (5) ◽  
pp. 1064-1084 ◽  
Author(s):  
A Miettinen ◽  
J L Stow ◽  
S Mentone ◽  
M G Farquhar

Antibodies specific for the core protein of basement membrane HSPG (Mr = 130,000) were administered to rats by intravenous injection, and the pathologic consequences on the kidney were determined at 3 min to 2 mo postinjection. Controls were given antibodies against gp330 (the pathogenic antigen of Heymann nephritis) or normal rabbit IgG. The injected anti-HSPG(GBM) IgG disappeared rapidly (by 1 d) from the circulation. The urinary excretion of albumin increased in a dose-dependent manner during the first 4 d, was increased 10-fold at 1-2 mo, but remained moderate (mean = 12 mg/24 h). By immunofluorescence the anti-HSPG(GBM) was seen to bind rapidly (by 3 min) to all glomerular capillaries, and by immunoperoxidase staining the anti-HSPG was seen to bind exclusively to the laminae rarae of the GBM where it remained during the entire 2-mo observation period. C3 was detected in glomeruli immediately after the injection (3 min), where it bound exclusively to the lamina rara interna; the amount of C3 bound increased up to 2 h but decreased rapidly thereafter, and was not detectable after 4 d. Mononuclear and PMN leukocytes accumulated in glomerular capillaries, adhered to the capillary wall, and extended pseudopodia through the endothelial fenestrae to contact in the LRI of the GBM where the immune deposits and C3 were located. At 1 wk postinjection, staining for C3 reappeared in the glomeruli of some of the rats, and by this time most of the rats, including controls injected with normal rabbit IgG, had circulating anti-rabbit IgG (by ELISA) and linear deposits of rat IgG along the GBM (by immunofluorescence). Beginning at 9 d, there was progressive subepithelial thickening of the GBM which in some places was two to three times its normal width. This thickening was due to the laying down of a new layer of basement membrane-like material on the epithelial side of the GBM, which gradually displaced the old basement membrane layers toward the endothelium. The results show that the core proteins of this population of basement membrane HSPG (Mr = 130,000), which are ubiquitous components of basement membranes, are exposed to the circulation and can bind anti-HSPG(GBM) IgG in the laminae rarae of the GBM. Binding of these antibodies to the GBM leads to changes (C3 deposition, leukocyte adherence, moderate proteinuria, GBM thickening) considered typical of the acute phase of anti-GBM glomerulonephritis. Antibody binding interferes with the normal turnover of the GBM, presumably by affecting the biosynthesis and/or degradation of basement membrane components.


1967 ◽  
Vol 125 (4) ◽  
pp. 595-606 ◽  
Author(s):  
Sidney Rothbard ◽  
Robert F. Watson

Rabbit serum containing antibody to human collagen, perfused through human infant kidneys obtained at autopsy, gives an immunofluorescent reaction with an antigen in the basement membranes of the glomeruli and the tubules. This reaction was shown to be specific by the absence of reaction with normal rabbit serum, antibody to carp collagen, or anti-human collagen serum absorbed with human collagen. Slight cross-reactions were found in the human kidneys with antibody to chicken or rat collagen. There was no evidence that a collagen-like protein in human serum or an antigen common to human erythrocytes and renal glomeruli enters into this immunofluorescent reaction. Perfusion of the kidneys with purified collagenase before the introduction of the antibody to human collagen altered the antigen so that antibody could not be demonstrated in the basement membranes by immunofluorescence. Testicular hyaluronidase used in the same way did not affect the immunofluorescent reaction. This method of perfusion provides another means for studying antigens in human organs by immunofluorescence. These observations in human kidneys extend our earlier findings in laboratory animals and indicate that an antigen, collagen, is also present in human renal glomerular and tubular basement membranes.


1980 ◽  
Vol 86 (2) ◽  
pp. 682-687 ◽  
Author(s):  
J A Madri ◽  
F J Roll ◽  
H Furthmayr ◽  
J M Foidart

Affinity-purified rabbit antibodies specific for two large noncollagenous gycoproteins--laminin and fibronectin--were used to study the distribution of these proteins in normal murine kidneys. Immunofluorescence staining of conventional frozen sections demonstrates fibronectin within mesangial areas of the glomerulus. Laminin is also found in mesangial areas. However, it also appears to be distributed in typical basement membranelike patterns on glomerular and tubular basement membranes and Bowman's capsule. At the ultrastructural level, by labeling 600-800-A thick frozen sections with a three-stage procedure consisting of specific antibodies, biotinyl sheep anti-rabbit IgG, and avidin-ferritin conjugates, fibronectin is present ony in the mesangial matrix and is specifically localized to areas immediately surrounding mesangial cell processes. Laminin, on the other hand, is found uniformly distributed throughout tubular basement membranes, the mesangial matrix, and Bowman's capsule. In glomerular basement membranes, laminin labeling is restricted to the lamina rara interna and adjacent regions of the lamina densa.


2003 ◽  
Vol 2003 (196) ◽  
pp. pe34-pe34 ◽  
Author(s):  
N. J. Boudreau

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