Metanephric Blastema

2011 ◽  
Keyword(s):  
Metanephric Blastema

Temporal changes in the expression of the insulin-like growth factor II gene associated with tissue maturation in the human fetus

Development ◽  
1989 ◽  
Vol 106 (3) ◽  
pp. 543-554 ◽  
Author(s):  
A.L. Brice ◽  
J.E. Cheetham ◽  
V.N. Bolton ◽  
N.C. Hill ◽  
P.N. Schofield
Keyword(s):  
Growth Factor ◽  
Cell Types ◽  
Specific Cell ◽  
Insulin Like Growth Factor ◽  
Vitro Fertilization ◽  
Age Related ◽  
Factor Ii ◽  
Metanephric Blastema

The insulin-like growth factors are broadly distributed in the human conceptus and are thought to play a role in the growth and differentiation of tissues during development. Using in situ hybridization we have shown that a wide variety of specific cell types within tissues express the gene for insulin-like growth factor II at times of development from 18 days to 14 weeks of gestation. Examination of blastocysts produced by in vitro fertilization showed no expression, thus bracketing the time of first accumulation of IGF-II mRNA to between 5 and 18 days postfertilization. The pattern of IGF-II expression shows specific age-related differences in different tissues. In the kidney, for example, expression is found in the cells of the metanephric blastema which is dramatically reduced as the blastema differentiates. The reverse is also seen, and we have noted an increase in expression of IGF-II in the cytotrophoblast layer of the placenta with gestational age. The sites of expression do not correlate with areas of either high mitotic activity or specific types of differentiation, but the observed pattern of expression in the kidney, adrenal glands and liver suggests an explanation for the abnormally high IGF-II mRNA expression in developmental tumours such as Wilms' tumour.

Proteoglycans are required for maintenance of Wnt-11 expression in the ureter tips

Development ◽  
1996 ◽  
Vol 122 (11) ◽  
pp. 3627-3637 ◽  
Author(s):  
A. Kispert ◽  
S. Vainio ◽  
L. Shen ◽  
D.H. Rowitch ◽  
A.P. McMahon
Keyword(s):  
Collecting Duct ◽  
Expression Patterns ◽  
Branching Morphogenesis ◽  
Proteoglycan Synthesis ◽  
Metanephric Mesenchyme ◽  
Ureteric Bud ◽  
Metanephric Kidney ◽  
Specific Factors ◽  
Collecting Duct Epithelium ◽  
Metanephric Blastema

Development of the metanephric kidney requires the concerted interaction of two tissues, the epithelium of the ureteric duct and the metanephric mesenchyme. Signals from the ureter induce the metanephric mesenchyme to condense and proliferate around the ureter tip, reciprocal signals from the mesenchyme induce the ureter tip to grow and to branch. Wnt genes encode secreted glycoproteins, which are candidate mediators of these signaling events. We have identified three Wnt genes with specific, non-overlapping expression patterns in the metanephric kidney, Wnt-4, Wnt-7b and Wnt-11. Wnt-4 is expressed in the condensing mesenchyme and the comma- and S-shaped bodies. Wnt-7b is expressed in the collecting duct epithelium from 13.5 days post coitum onward. Wnt-1l is first expressed in the nephric duct adjacent to the metanephric blastema prior to the outgrowth of the ureteric bud. Wnt-l1 expression in Danforth's short-tail mice suggests that signaling from the mesenchyme may regulate Wnt-ll activation. During metanephric development, Wnt-11 expression is confined to the tips of the branching ureter. Maintenance of this expression is independent of Wnt-4 signaling and mature mesenchymal elements in the kidney. Moreover, Wnt-ll expression is maintained in recombinants between ureter and lung mesenchyme suggesting that branching morphogenesis and maintenance of Wnt-ll expression are independent of metanephric mesenchyme-specific factors. Interference with proteoglycan synthesis leads to loss of Wnt-ll expression in the ureter tip. We suggest that Wnt-11 acts as an autocrine factor within the ureter epithelium and that its expression is regulated at least in part by proteoglycans.

Transplantation of rat metanephroi into mice

2001 ◽  
Vol 280 (6) ◽  
pp. R1865-R1869 ◽  
Author(s):  
Sharon A. Rogers ◽  
Marc R. Hammerman
Keyword(s):  
Endothelial Cells ◽  
Ureteric Bud ◽  
Rat Embryos ◽  
Glomerular Capillary ◽  
Metanephric Blastema

To determine whether transplanted metanephroi grow and differentiate after implantation into the omentum in hosts of a different species, we implanted metanephroi from embryonic day 15 (E15) rat embryos into uninephrectomized mice (hosts). Some host mice received human CTLA4Ig (hCTLA4Ig), anti-CD45RB, and anti-CD154 (tolerance-inducing agents). E15 metanephroi contained only metanephric blastema, segments of ureteric bud, and primitive nephrons with no glomeruli. Rat metanephroi did not grow or differentiate in mice that received no tolerance-inducing agents. However, by 2 wk posttransplantation in mice that received hCTLA4Ig, anti-CD45RB, and anti-CD154, metanephroi from E15 rats had enlarged, become vascularized, and formed mature tubules and glomeruli. Rat metanephroi contained cells that stained specifically for mouse CD31, a marker for sprouting endothelial cells. Some rat glomerular capillary loops stained positively for mouse CD31. Here, we show that chimeric kidneys develop from metanephroi transplanted rat→mouse and that glomeruli are vascularized, at least in part, by host vessels.

scholarly journals Nephrogenic rests and nephroblastomatosis: literature review and clinical reports

2020 ◽  
Vol 7 (3) ◽  
pp. 119-124
Author(s):  
L. I. Shats ◽  
B. V. Kondratiev ◽  
M. B. Belogurova
Keyword(s):  
Literature Review ◽  
Wilms Tumor ◽  
Renal Parenchyma ◽  
The Other ◽  
Wilms Tumour ◽  
Different Types ◽  
Nephrogenic Rests ◽  
Metanephric Blastema

Nephrogenic rests and nephroblastomatosis describe persistence of embryonic renal parenchyma (metanephric blastema) beyond 36 weeks of gestation, when nephrogenesis is normally complete. This persistent metanephric blastema may transform into the Wilms tumor, and are detected in 30–40 % of unilateral nephroblstoma and nearly 100 % in bilateral cases. The risk of Wilms tumour is increased in any type of nephrogenic rests/nephroblastomatosis but it is higher in infants and in patients with intralobar nephrogenic rests. We cite below several studies described different types of nephrogenic rests, their connection with nephroblastoma development and the details of diagnostic. We refer to clinical examples, in that regard. Two cases are presented: bilateral diffuse hyperplastic perilobar nephroblastomatosis in one child and an infant with combination of perilobar nephrogenic rests in one kidney and Wilms tumour in the other kidney.

Metanephric osteopontin regulates nephrogenesis in vitro

1997 ◽  
Vol 272 (4) ◽  
pp. F469-F476 ◽  
Author(s):  
S. A. Rogers ◽  
B. J. Padanilam ◽  
K. A. Hruska ◽  
C. M. Giachelli ◽  
M. R. Hammerman
Keyword(s):  
Immunohistochemical Staining ◽  
Ureteric Bud ◽  
Organ Cultures ◽  
Rat Embryos ◽  
Beta3 Integrin ◽  
Arginine Glycine Aspartic Acid ◽  
Renal Expression ◽  
Metanephric Blastema

Renal expression of osteopontin is enhanced in the setting of acute ischemic injury. Because of the parallels that exist between recovery from renal ischemia and renal development, we characterized the role that osteopontin plays during metanephrogenesis in the rat. Osteopontin mRNA is present in kidneys obtained from rat embryos as early as embryonic day 13 (E13). Immunohistochemical staining of metanephroi obtained from E16 rat embryos and metanephroi obtained from E13 embryos and cultured for 3 days in vitro demonstrated that osteopontin is expressed both in the developing nephron and in the ureteric bud. Addition of anti-osteopontin antibodies to metanephric organ cultures results in failure of the metanephric blastema to undergo normal tubulogenesis. Addition of the arginine-glycine-aspartic acid-containing peptide, cyclo-RGDfV, or the anti-alpha(v)beta3-integrin antibody, LM609, to cultures has a similar effect. These findings establish that osteopontin is produced within the rat metanephros during development in vivo and suggest that the binding of osteopontin to the alpha(v)beta3-integrin is required for tubulogenesis to occur in vitro. Blastemal cells within metanephroi cultured in the presence of OP199 manifest increased apoptosis compared with controls. It is possible that osteopontin plays an important anti-apoptotic role during the process of metanephric blastema condensation that is a prerequisite for the formation of nephrons in vivo.

Deficient Metanephric Blastema—A Cause of Oligomeganephronia?

1994 ◽  
Vol 14 (6) ◽  
pp. 935-943 ◽  
Author(s):  
Steven V. Foster ◽  
Edith P. Hawkins
Keyword(s):  
Metanephric Blastema

The metanephric blastema differentiates into collecting system and nephron epithelia in vitro

Development ◽  
1995 ◽  
Vol 121 (10) ◽  
pp. 3207-3214 ◽  
Author(s):  
J. Qiao ◽  
D. Cohen ◽  
D. Herzlinger
Keyword(s):  
Cell Fate ◽  
Mesenchymal Cells ◽  
Lacz Gene ◽  
Metanephric Mesenchyme ◽  
Ureteric Bud ◽  
Ureteric Buds ◽  
Collecting System ◽  
Metanephric Blastema

The kidney forms from two tissue populations derived from intermediate mesoderm, the ureteric bud and metanephric mesenchyme. It is currently accepted that metanephric mesenchyme is committed to differentiating into nephrons while the ureteric bud is restricted to forming the renal collecting system. To test this hypothesis, we transferred lacZ into pure metanephric mesenchyme isolated from gestation day 13 rat embryos. The fate of tagged mesenchymal cells and their progeny was characterized after co-culture with isolated ureteric buds. When induced to differentiate by the native inducer of kidney morphogenesis, lineage-tagged mesenchymal cells exhibit the potential to differentiate into collecting system epithelia, in addition to nephrons. The fate of cells deriving from isolated ureteric buds was also examined and results of these lacZ gene transfer experiments indicate that the majority of ureteric bud cells differentiate into the renal collecting system. These cell fate studies combined with in situ morphological observations raise the possibility that collecting system morphogenesis in vivo occurs by growth of the ureteric bud and recruitment of mesenchymal cells from the metanephric blastema. Thus, metanephric mesenchyme may be a pluripotent renal stem population.

scholarly journals Insulin-like growth factor (IGF) and IGF binding protein gene expression in multicystic renal dysplasia.

1997 ◽  
Vol 8 (1) ◽  
pp. 85-94
Author(s):  
D G Matsell ◽  
T Bennett ◽  
R A Armstrong ◽  
P Goodyer ◽  
C Goodyer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Renal Dysplasia ◽  
Multicystic Dysplastic Kidney ◽  
Fetal Life ◽  
Histopathological Changes ◽  
Mesenchymal Tissue ◽  
Multicystic Renal Dysplasia ◽  
Igf Binding ◽  
Metanephric Blastema ◽  
Igfbp 3

Multicystic dysplastic kidney disease is the most common form of renal dysplasia that leads to ESRD in children. This study describes the histopathological changes of multicystic dysplasia that occur from early fetal life to the postnatal period. At 14 wk gestation, early cystic enlargement of various segments of the nephron have been identified, in addition to a displaced metanephric blastema adjacent to zones of normal nephrogenesis. At later stages, the predominant features include cyst enlargement with marked fibromuscular collars, architectural disorganization, and replacement of the interstitium with a disarray of mesenchymal tissue. This study investigated the expression of the mRNA encoding the insulin-like growth factors (IGF) and IGF binding proteins (IGFBP) and have demonstrated IGF-II, IGFBP-2, and IGFBP-3 to be altered. Apart from their expression in the displaced metanephric blastema, both IGF-II and IGFBP-2 were overexpressed in abnormal tissue elements in all kidneys from fetal to postnatal life. IGF-II gene expression was localized to mesenchymal tissue, specifically in the periductal fibromuscular collars. IGFBP-2 mRNA was found to be expressed exclusively in the cyst epithelia of all cysts at all ages studied, whereas IGFBP-3 mRNA was absent from these epithelia. This study details the failure of normal IGF expression in the development of multicystic renal dysplasia and suggests a role for the IGF system in the progressive histopathological changes of this disorder.

Phosphomonoesterase Content and Localization in the Meso- and Metanephros of the Chick Embryo

1952 ◽  
Vol s3-93 (23) ◽  
pp. 247-258
Author(s):  
L.C. U. JUNQUEIRA
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Border Zone ◽  
Rapid Rise ◽  
High Concentration ◽  
Acid And Alkaline Phosphatase ◽  
Alkaline And Acid Phosphatase ◽  
And Function ◽  
Metanephric Blastema

Chemical determinations were made of the alkaline and acid phosphatase content of meso- and metanephros of chick embryos between 4 days of incubation and 6 days after hatching. Histochemical localization of alkaline phosphatase and of ribonuclease-removable asiphilia was also studied in these organs. A study of the data obtained suggest the following conclusions: 1. The acid and alkaline phosphatase activity of the mesonephros increases from the 4th to the 16th day, decreasing from then onwards. 2. The acid and alkaline phosphatase activity of the metanephros increases from the 4th to the 16th day, decreasing slowly to the 20th day. A rapid rise is observed after hatching. 3. The alkaline phosphatase activity that is diffusely located in the cells of recently formed secretory tubules of the meso- and metanephros polarizes to the brush border zone later on. 4. Ribonuclease-removable basiphilia, abundant in the mesonephric tubules up to the 6th day of incubation, decreases from then onwards. 5. The metanephric blastema and tubules present a high concentration of ribonuclease-removable basiphilia up to the 13th day. From then on its content decreases in the whole organ with the exception of certain groups of cells still in differentiation. The possible correlation between these findings and meso- and metanephros differentiation and function is discussed.

Sign in / Sign up

Export Citation Format

Share Document