scholarly journals Origin of the glomerular basement membrane visualized after in vivo labeling of laminin in newborn rat kidneys.

1985 ◽  
Vol 100 (6) ◽  
pp. 1988-2000 ◽  
Author(s):  
D R Abrahamson
Keyword(s):  
Basement Membrane ◽  
Developmental Stages ◽  
Cell Types ◽  
Basement Membranes ◽  
Newborn Rats ◽  
Mature Adult ◽  
Capillary Loop ◽  
Double Label

To examine the origin and assembly of glomerular basement membranes (GBMs), affinity purified anti-laminin IgG was directly coupled to horseradish peroxidase (HRP) and intravenously injected into newborn rats. Kidneys were then processed for peroxidase histochemistry and microscopy. Within 1 h after injection, anti-laminin bound to basement membranes of nephrons in all developmental stages (vesicle, comma, S-shaped, developing capillary loop, and maturing glomeruli). In S-shaped and capillary loop glomeruli, anti-laminin-HRP labeled a double basal lamina between the endothelium and epithelium. Sections incubated with anti-laminin in vitro showed labeling within the rough endoplasmic reticulum of endothelium and epithelium, indicating that both cell types synthesized laminin for the double basement membrane. In maturing glomeruli, injected anti-laminin-HRP bound throughout the GBMs, and double basement membranes were rarely observed. At this stage, however, numerous knobs or outpockets of basement membrane material extending far into the epithelial side of the capillary wall were identified and these were also labeled throughout their full thickness. No such outpockets were found in the endothelial cell layer of newborn rats (and they normally are completely absent in fully mature, adult glomeruli). In contrast with these results, in kidneys fixed 4-6 d after anti-laminin IgG-HRP injection, basement membranes of vesicle, comma, and S-shaped nephrons were unlabeled, indicating that they were assembled after injection. GBM labeling was seen in maturing glomeruli, however. In addition, the outpockets of basement membrane extending into the epithelium were often completely unlabeled whereas GBMs lying immediately beneath them were labeled intensely, which indicates that the outpockets were probably assembled by the epithelium. Injections of sheep anti-laminin IgG followed 8 d later with injections of biotin-rabbit anti-laminin IgG and double-label immunofluorescence microscopy confirmed that GBM formation continued during individual capillary loop expansion. GBM assembly therefore occurs by at least two different processes at separate times in development: (a) fusion of endothelial and epithelial basement membranes followed by (b) addition of new basement membrane from the epithelium into existing GBMs.

scholarly journals Designing Cardiovascular Implants Taking in View the Endothelial Basement Membrane

2021 ◽  
Vol 22 (23) ◽  
pp. 13120
Author(s):  
Skadi Lau ◽  
Manfred Gossen ◽  
Andreas Lendlein
Keyword(s):  
Basement Membrane ◽  
Cell Types ◽  
Adjacent Cell ◽  
Design Strategies ◽  
Graft Thrombosis ◽  
Future Design ◽  
Early Graft ◽  
Endothelial Basement Membrane

Insufficient endothelialization of cardiovascular grafts is a major hurdle in vascular surgery and regenerative medicine, bearing a risk for early graft thrombosis. Neither of the numerous strategies pursued to solve these problems were conclusive. Endothelialization is regulated by the endothelial basement membrane (EBM), a highly specialized part of the vascular extracellular matrix. Thus, a detailed understanding of the structure–function interrelations of the EBM components is fundamental for designing biomimetic materials aiming to mimic EBM functions. In this review, a detailed description of the structure and functions of the EBM are provided, including the luminal and abluminal interactions with adjacent cell types, such as vascular smooth muscle cells. Moreover, in vivo as well as in vitro strategies to build or renew EBM are summarized and critically discussed. The spectrum of methods includes vessel decellularization and implant biofunctionalization strategies as well as tissue engineering-based approaches and bioprinting. Finally, the limitations of these methods are highlighted, and future directions are suggested to help improve future design strategies for EBM-inspired materials in the cardiovascular field.

scholarly journals Preliminary evaluations of 3-dimensional human skin models for their ability to facilitate in vitro the long-term development of the debilitating obligatory human parasite Onchocerca volvulus

2020 ◽  
Vol 14 (11) ◽  
pp. e0008503
Author(s):  
Christoph Malkmus ◽  
Shabnam Jawahar ◽  
Nancy Tricoche ◽  
Sara Lustigman ◽  
Jan Hansmann
Keyword(s):  
Adipose Tissue ◽  
Developmental Stages ◽  
Onchocerca Volvulus ◽  
River Blindness ◽  
Mature Adult ◽  
3 Dimensional ◽  
Human Parasite

Onchocerciasis also known as river blindness is a neglected tropical disease and the world's second-leading infectious cause of blindness in humans; it is caused by Onchocerca volvulus. Current treatment with ivermectin targets microfilariae and transmission and does not kill the adult parasites, which reside within subcutaneous nodules. To support the development of macrofilaricidal drugs that target the adult worm to further support the elimination of onchocerciasis, an in-depth understanding of O. volvulus biology especially the factors that support the longevity of these worms in the human host (>10 years) is required. However, research is hampered by a lack of access to adult worms. O. volvulus is an obligatory human parasite and no small animal models that can propagate this parasite were successfully developed. The current optimized 2-dimensional (2-D) in vitro culturing method starting with O. volvulus infective larvae does not yet support the development of mature adult worms. To overcome these limitations, we have developed and applied 3-dimensional (3-D) culture systems with O. volvulus larvae that simulate the human in vivo niche using in vitro engineered skin and adipose tissue. Our proof of concept studies have shown that an optimized indirect co-culture of in vitro skin tissue supported a significant increase in growth of the fourth-stage larvae to the pre-adult stage with a median length of 816–831 μm as compared to 767 μm of 2-D cultured larvae. Notably, when larvae were co-cultured directly with adipose tissue models, a significant improvement for larval motility and thus fitness was observed; 95% compared to 26% in the 2-D system. These promising co-culture concepts are a first step to further optimize the culturing conditions and improve the long-term development of adult worms in vitro. Ultimately, it could provide the filarial research community with a valuable source of O. volvulus worms at various developmental stages, which may accelerate innovative unsolved biomedical inquiries into the parasite’s biology.

scholarly journals Endothelial Cell-Pericyte Interactions Stimulate Basement Membrane Matrix Assembly: Influence on Vascular Tube Remodeling, Maturation, and Stabilization

2011 ◽  
Vol 18 (1) ◽  
pp. 68-80 ◽  
Author(s):  
Amber N. Stratman ◽  
George E. Davis
Keyword(s):  
Growth Factor ◽  
Basement Membrane ◽  
Basement Membranes ◽  
Heparin Binding ◽  
Matrix Assembly ◽  
Matrix Deposition ◽  
Vascular Basement Membrane ◽  
Membrane Matrix

AbstractExtracellular matrix synthesis and deposition surrounding the developing vasculature are critical for vessel remodeling and maturation events. Although the basement membrane is an integral structure underlying endothelial cells (ECs), few studies, until recently, have been performed to understand its formation in this context. In this review article, we highlight new data demonstrating a corequirement for ECs and pericytes to properly deposit and assemble vascular basement membranes during morphogenic events. In EC only cultures or under conditions whereby pericyte recruitment is blocked, there is a lack of basement membrane assembly, decreased vessel stability (with increased susceptibility to pro-regressive stimuli), and increased EC tube widths (a marker of dysfunctional EC-pericyte interactions). ECs and pericytes both contribute basement membrane components and, furthermore, both cells induce the expression of particular components as well as integrins that recognize them. The EC-derived factors—platelet derived growth factor-BB and heparin binding-epidermal growth factor—are both critical for pericyte recruitment to EC tubes and concomitant vascular basement membrane formationin vitroandin vivo. Thus, heterotypic EC-pericyte interactions play a fundamental role in vascular basement membrane matrix deposition, a critical tube maturation event that is altered in key disease states such as diabetes and cancer.

Altered synthesis of laminin 1 and absence of basement membrane component deposition in (beta)1 integrin-deficient embryoid bodies

2000 ◽  
Vol 113 (2) ◽  
pp. 259-268 ◽  
Author(s):  
M. Aumailley ◽  
M. Pesch ◽  
L. Tunggal ◽  
F. Gaill ◽  
R. Fassler
Keyword(s):  
Basement Membrane ◽  
Collagen Iv ◽  
Basement Membranes ◽  
Mouse Genetics ◽  
Embryoid Bodies ◽  
Membrane Formation ◽  
Beta 1 Integrin ◽  
Laminin 1

Basement membranes are the earliest extracellular matrices produced during embryogenesis. They result from synthesis and assembly into a defined supramolecular architecture of several components, including laminins, collagen IV, nidogen, and proteoglycans. In vitro studies have allowed us to propose an assembly model based on the polymerisation of laminin and collagen IV in two separate networks associated together by nidogen. How nucleation of polymers and insolubilisation of the different components into a basement membrane proceed in vivo is, however, unknown. A most important property of several basement membrane components is to provide signals controling the activity of adjacent cells. The transfer of information is mediated by interactions with cell surface receptors, among them integrins. Mouse genetics has demonstrated that the absence of these interactions is not compatible with development as deletion of either laminin (gamma)1 chain or integrin (beta)1 chain lead to lethality of mouse embryos at the peri-implantation stage. We have used embyoid bodies as a model system recapitulating the early steps of embryogenesis to unravel the respective roles of laminin and (beta)1 integrins in basement membrane formation. Our data show that there is formation of a basal lamina in wild-type, but not in (beta)1-integrin deficient, embryoid bodies. Surprisingly, in the absence of (beta)1 integrins, laminin 1 was not secreted in the extracellular space due to a rapid switch off of laminin (alpha)1 chain synthesis which normally drives the secretion of laminin heterotrimers. These results indicate that (beta)1 integrins are required for the initiation of basement membrane formation, presumably by applying a feed-back regulation on the expression of laminin (alpha)1 chain and other components of basement membranes.

scholarly journals Renal glomerular proteoglycans. An investigation of their synthesis in vivo using a technique for fixation in situ

1988 ◽  
Vol 251 (2) ◽  
pp. 411-418 ◽  
Author(s):  
L A Beavan ◽  
M Davies ◽  
R M Mason
Keyword(s):  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Membrane Fraction ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Basement Membranes ◽  
Chondroitin Sulphate Proteoglycans

Newly synthesized rat glomerular [35S]proteoglycans were labelled in vivo after injecting Na2[35S]SO4 intraperitoneally. At the end of the labelling period (7 h) the kidneys were perfused in situ with 0.01% (w/v) cetylpyridinium chloride. This fixed proteoglycans in the tissue and increased their recovery 2-3-fold during subsequent isolation of glomeruli from the renal cortex. The glomeruli were fractionated by a modified osmotic lysis and detergent extraction procedure [Meezan, Brendel, Hjelle & Carlson (1978) in The Biology and Chemistry of Basement Membranes (Kefalides, N.A., ed.), Academic Press, New York; Kanwar & Farquhar (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 4493-4497] to obtain a basement membrane preparation. The proteoglycans released at each stage of the procedure were characterized using DEAE-Sephacel ion-exchange chromatography, chondroitinase ABC and HNO2 digestion and Sepharose CL-4B gel-permeation chromatography. About 85% of the [35S]proteoglycans synthesized were of the heparan sulphate variety, the remainder being chondroitin sulphate proteoglycans. Three sizes of heparan sulphate proteoglycans were identified. The largest (HS1, Kav. 0.47) accounts for 44% of the total extractable heparan sulphates. About one third of HS1 were extracted from the glomerular basement-membrane fraction with 8 M-urea and 4 M-guanidine hydrochloride but the remainder were released from the glomerulus during preparation of the fraction. The two smaller molecules (HS2, Kav. 0.56 and HS3, Kav. 0.68) accounted for 27% and 28% of the extractable heparan sulphate respectively and were not associated with the basement membrane fraction. HS1, HS2 and HS3 were also isolated from non-fixed glomeruli labelled in vivo but with much lower recovery. In glomeruli labelled in vitro, heparan sulphate accounted for only 35% of the proteoglycans, the remainder being of the chondroitin sulphate type. Proteoglycans similar to HS1, HS2 and HS3 were present in glomeruli labelled in vitro but, in addition, a large, highly charged heparan sulphate (HS1a) was extracted from the glomerular basement-membrane fraction of these glomeruli. It accounted for 6% of the total heparan sulphate.

Most lymphoid organ dendritic cell types are phenotypically and functionally immature

Blood ◽  
2003 ◽  
Vol 102 (6) ◽  
pp. 2187-2194 ◽  
Author(s):  
Nicholas S. Wilson ◽  
Dima El-Sukkari ◽  
Gabrielle T. Belz ◽  
Christopher M. Smith ◽  
Raymond J. Steptoe ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Cell Types ◽  
Lymphoid Organ ◽  
Lymphoid Organs ◽  
Peripheral Tolerance ◽  
Mature Stage ◽  
Peripheral Tissues ◽  
Mhc Ii

Abstract Dendritic cells (DCs) have been thought to follow a life history, typified by Langerhans cells (LCs), with 2 major developmental stages: an immature stage that captures antigens in the periphery and a mature stage that presents those antigens in the lymphoid organs. However, a systematic assessment of the maturity of lymphoid organ DCs has been lacking. We have analyzed the maturity of the DC types found in the steady state in the spleen, lymph nodes (LNs), and thymus. The DCs that migrate into the iliac, mesenteric, mediastinal, or subcutaneous LNs from peripheral tissues were mature and therefore could not process and present newly encountered antigens. However, all the other DC types were phenotypically and functionally immature: they expressed low levels of surface major histocompatibility complex class II (MHC II) and CD86, accumulated MHC II in their endosomes, and could present newly encountered antigens. These immature DCs could be induced to mature by culture in vitro or by inoculation of inflammatory stimuli in vivo. Therefore, the lymphoid organs contain a large cohort of immature DCs, most likely for the maintenance of peripheral tolerance, which can respond to infections reaching those organs and mature in situ.

scholarly journals Anionic sites in the glomerular basement membrane. In vivo and in vitro localization to the laminae rarae by cationic probes.

1979 ◽  
Vol 81 (1) ◽  
pp. 137-153 ◽  
Author(s):  
Y S Kanwar ◽  
M G Farquhar
Keyword(s):  
Ionic Strength ◽  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Left Kidney ◽  
High Ionic Strength ◽  
Basement Membranes ◽  
Mesangial Matrix ◽  
Anionic Sites

Cationized ferritin (CF) of narrow pI range (7.3-7.5) and the basic dye ruthenium red (RR) have been used as cationic probes to partially characterize anionic sites previously demonstrated in the glomerular basement membrane (GBM). When CF was given i.v. to normal rats and the left kidney was fixed by perfusion 15 min thereafter, clusters of CF molecules were found throughout the lamina rara interna (LRI), lamina rara externa (LRE), and mesangial matrix distributed at regular (approximately 60 nm) intervals. When kidneys were perfused with aldehyde fixative containing RR, small (20 nm) RR-stained particles were seen in the same locations distributed with the same 60 nm repeating pattern, forming a quasiregular, lattice-like arrangement. Fine (approximately 3 nm) filaments connected the sites and extended between them and the membranes of adjoining endothelial and epithelial cells. When CF was given i.v. followed by perfusion with RR in situ, both probes localized to the same sites. CF remained firmly bound after prolonged perfusion with 0.1-0.2 M KCl or NaCl. It was displaced by perfusion with buffers of high ionic strength (0.4-0.5 M KCl) or pH (less than 3.0 or greater than 10.0). CF also bound (clustered at approximately 60 nm intervals) to isolated GBM's, and binding was lost when such isolated GBM's were treated with buffers of high ionic strength or pH. These experiments demonstrate the existence of a quasi-regular, lattice-like network of anionic sites in the LRI and LRE and the mesangial matrix. The sites are demonstrable in vivo (by CF binding), in fixed kidneys (by RR staining), and in isolated GBM's (by CF binding). The results obtained with CF show that the binding of CF (and probably also RR) to the laminae rarae is electrostatic in nature since it is displaced by treatment with buffers of high ionic strength or pH. With RR the sites resemble in morphology and staining properties the proteoglycan particles found in connective tissue matrices and in association with basement membranes in several other locations.

scholarly journals Extracellular matrix components of the mouse thymus microenvironment: ontogenetic studies and modulation by glucocorticoid hormones.

1991 ◽  
Vol 39 (11) ◽  
pp. 1539-1546 ◽  
Author(s):  
J Lannes-Vieira ◽  
M Dardenne ◽  
W Savino
Keyword(s):  
Extracellular Matrix ◽  
Basement Membrane ◽  
Type I Collagen ◽  
Basement Membranes ◽  
Thymic Epithelial Cell ◽  
Epithelial Cell Line ◽  
Type I ◽  
Extracellular Matrix Components

The present investigation was an ontogenetic study on the distribution of extracellular matrix (ECM) components in the thymic microenvironment of C57BL/6 mice (comprising young and old adults and developing embryos) and NZB mice. In addition, we evaluated the in vivo and in vitro influence of hydrocortisone treatment on basement membrane protein production by a thymic epithelial cell line. In young normal animals, Type I collagen was restricted to the interstitial spaces of the capsule and septa, where Type IV collagen, fibronectin, and laminin could be detected in the basement membranes. In addition, fibronectin-containing fibers were seen within the medulla of the thymic lobules. The ECM distribution pattern in the developing embryos was distinct from that observed in adults, since a fine meshwork of basement membrane-containing proteins was clearly seen throughout the parenchyma. Moreover, aging normal and NZB mice exhibited a denser ECM pattern than young adult normal animals. Treatment with hydrocortisone, both in vivo and in vitro, resulted in enhancement of ECM expression, detected in mice as early as 2 hr post injection and lasting for several days. Considering that the fluctuations of ECM expression parallel important events in thymocyte differentiation, we discuss the possibility that the two phenomena may be associated.

Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

1990 ◽  
Vol 48 (3) ◽  
pp. 914-915
Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Umbilical Vein ◽  
Cell Types ◽  
Amelanotic Melanoma ◽  
Cytoplasmic Process ◽  
Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

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