scholarly journals Identification and characterization of a fibroblast marker: FSP1.

1995 ◽  
Vol 130 (2) ◽  
pp. 393-405 ◽  
Author(s):  
F Strutz ◽  
H Okada ◽  
C W Lo ◽  
T Danoff ◽  
R L Carone ◽  
...  

We performed subtractive and differential hybridization for transcript comparison between murine fibroblasts and isogenic epithelium, and observed only a few novel intracellular genes which were relatively specific for fibroblasts. One such gene encodes a filament-associated, calcium-binding protein, fibroblast-specific protein 1 (FSP1). The promoter/enhancer region driving this gene is active in fibroblasts but not in epithelium, mesangial cells or embryonic endoderm. During development, FSP1 is first detected by in situ hybridization after day 8.5 as a postgastrulation event, and is associated with cells of mesenchymal origin or of fibroblastic phenotype. Polyclonal antiserum raised to recombinant FSP1 protein stained the cytoplasm of fibroblasts, but not epithelium. Only occasional cells stain with specific anti-FSP1 antibodies in normal parenchymal tissue. However, in kidneys fibrosing from persistent inflammation, many fibroblasts could be identified in interstitial sites of collagen deposition and also in tubular epithelium adjacent to the inflammatory process. This pattern of anti-FSP1 staining during tissue fibrosis suggests, as a hypothesis, that fibroblasts in some cases arise, as needed, from the local conversion of epithelium. Consistent with this notion that FSP1 may be involved in the transition from epithelium to fibroblasts are experiments in which the in vitro overexpression of FSP1 cDNA in tubular epithelium is accompanied by conversion to a mesenchymal phenotype, as characterized by a more stellate and elongated fibroblast-like appearance, a reduction in cytokeratin, and new expression of vimentin. Similarly, tubular epithelium submerged in type I collagen gels exhibited the conversion to a fibroblast phenotype which includes de novo expression of FSP1 and vimentin. Use of the FSP1 marker, therefore, should further facilitate both the in vivo studies of fibrogenesis and the mapping of cell fate among fibroblasts.

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Martin Liu ◽  
Angelos Karagiannis ◽  
Matthew Sis ◽  
Srivatsan Kidambi ◽  
Yiannis Chatzizisis

Objectives: To develop and validate a 3D in-vitro model of atherosclerosis that enables direct interaction between various cell types and/or extracellular matrix. Methods and Results: Type I collagen (0.75 mg/mL) was mixed with human artery smooth muscle cells (SMCs; 6x10 5 cells/mL), medium, and water. Human coronary artery endothelial cells (HCAECs; 10 5 /cm 2 ) were plated on top of the collagen gels and activated with oxidized low density lipoprotein cholesterol (LDL-C). Monocytes (THP-1 cells; 10 5 /cm 2 ) were then added on top of the HCAECs. Immunofluorescence showed the expression of VE-cadherin by HCAECs (A, B) and α-smooth muscle actin by SMCs (A). Green-labelled LDL-C particles were accumulated in the subendothelial space, as well as in the cytoplasm of HCAECs and SMCs (C). Activated monocytes were attached to HCAECs and found in the subendothelial area (G-I). Both HCAECs and SMCs released IL-1β, IL-6, IL-8, PDGF-BB, TGF-ß1, and VEGF. Scanning and transmission electron microscopy showed the HCAECs monolayer forming gap junctions and the SMCs (D-F) and transmigrating monocytes within the collagen matrix (G-I). Conclusions: In this work, we presented a novel, easily reproducible and functional in-vitro experimental model of atherosclerosis that has the potential to enable in-vitro sophisticated molecular and drug development studies.


Author(s):  
Lowell Taylor Edgar ◽  
Margaret Julias ◽  
David I. Shreiber ◽  
Helen M. Buettner

Acupuncture is a traditional therapy originating in China almost 2000 years ago. Acupuncture has slowly been growing in popularity in the West, and clinical evidence has shown the potential for acupuncture as a low-cost ‘alternative’ therapy for an assortment of ailments [1]. The practice of acupuncture involves inserting fine needles into the skin followed by needle manipulation, usually by rotation. Recent studies by Langevin et al demonstrate that this rotation causes the subcutaneous connective tissue to couple to and wind around the needle [2–4], which suggests that mechanotransduction in the connective tissue might play a role in the therapeutic mechanisms that underlay acupuncture [2, 3]. To begin to decompose and quantify this complex mechanism at the tissue level in a controlled setting, we have simulated acupuncture in type I collagen gels in vitro, and have developed algorithms to quantify the tissue response following imaging with polarized light microscopy (PLM).


2021 ◽  
Author(s):  
Seyed Mohammad Siadat ◽  
Monica E Susilo ◽  
Jeffrey A Paten ◽  
Alexandra A Silverman ◽  
Charles A DiMarzio ◽  
...  

While de novo collagen fibril formation is well-studied, there are few investigations into the growth and remodeling of extant fibrils, where molecular collagen incorporation into and erosion from the fibril surface must delicately balance during fibril growth and remodeling. Observing molecule/fibril interactions is difficult, requiring the tracking of molecular dynamics while, at the same time, minimizing the effect of the observation on fibril structure and assembly. To address the observation-interference problem, exogenous collagen molecules are tagged with small fluorophores and the fibrillogenesis kinetics of labeled collagen molecules as well as the structure and network morphology of assembled fibrils are quantified for the first time. While excessive labeling significantly disturbs fibrillogenesis kinetics and network morphology of assembled fibrils, adding less than ~1.2 labels preserves them. Applications of the functional, labeled collagen probe are demonstrated in both cellular and acellular systems. The functional, labelled collagen associates strongly with native fibrils and when added to an in vitro model of corneal stromal development, is endocytosed rapidly by cells and is translocated into synthesized matrix networks within 24 hours.


MRS Advances ◽  
2016 ◽  
Vol 1 (18) ◽  
pp. 1283-1288
Author(s):  
Dilinazi Aishanjiang ◽  
Emily C. Green ◽  
Heng Li ◽  
Marilyn L. Minus

ABSTRACTCollagen is the most abundant protein present in the human body and found in connective tissues, bone, and tendon. It is also known as a natural resource for healing damaged skin tissues [1]. In this study, under specific microenvironment conditions, mimetic collagen gels were successfully formed synthetically from reconstituted Bovine type I collagen monomers. This was achieved by controlling ionic strength, temperature and pH, allowing fibrils with native mimetic D periodic banding structure to assemble spontaneously within the gels. In addition, by providing appropriate aging temperatures and times, mature collagen fibril growth is also realized in the gels in vitro. Mimetic gels were subsequently formed into fibers through a wet-spinning process. These spun fibers were found to preserve the native mimetic D periodic banding and fibrillar structure formed in the initial gels. As a result, the synthetic fibers resemble native tendon. Here structural development within the gel samples and fibers as a function of processing was analyzed by scanning electron microscopy (SEM). Results in this study also show a potentially new route for the fabrication of synthetic collagen fibers mimicking tendon, which may find applications as engineered tissues or scaffolding materials.


2001 ◽  
Vol 281 (1) ◽  
pp. L164-L171 ◽  
Author(s):  
Tadashi Mio ◽  
Xiangde Liu ◽  
Myron L. Toews ◽  
Yuichi Adachi ◽  
Debra J. Romberger ◽  
...  

Bradykinin is a multifunctional mediator of inflammation believed to have a role in asthma, a disorder associated with remodeling of extracellular connective tissue. Using contraction of collagen gels as an in vitro model of wound contraction, we assessed the effects of bradykinin tissue on remodeling. Human fetal lung fibroblasts were embedded in type I collagen gels and cultured for 5 days. After release, the floating gels were cultured in the presence of bradykinin. Bradykinin significantly stimulated contraction in a concentration- and time-dependent manner. Coincubation with phosphoramidon augmented the effect of 10−9 and 10−8 M bradykinin. A B2 receptor antagonist attenuated the effect of bradykinin, whereas a B1 receptor antagonist had no effect, suggesting that the effect is mediated by the B2 receptor. An inhibitor of intracellular Ca2+mobilization abolished the response; addition of EGTA to the culture medium attenuated the contraction of control gels but did not modulate the response to bradykinin. In contrast, the phospholipase C inhibitor U-73122 and the protein kinase C inhibitors staurosporine and GF-109203X attenuated the responses. These data suggest that by augmenting the contractility of fibroblasts, bradykinin may have an important role in remodeling of extracellular matrix that may result in tissue dysfunction in chronic inflammatory diseases, such as asthma.


Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 3890-3899 ◽  
Author(s):  
Stefano Zanotti ◽  
Anna Smerdel-Ramoya ◽  
Lisa Stadmeyer ◽  
Deena Durant ◽  
Freddy Radtke ◽  
...  

Notch receptors are determinants of cell fate decisions. To define the role of Notch in the adult skeleton, we created transgenic mice overexpressing the Notch intracellular domain (NICD) under the control of the type I collagen promoter. First-generation transgenics were small and osteopenic. Bone histomorphometry revealed that NICD caused a decrease in bone volume, secondary to a reduction in trabecular number; osteoblast and osteoclast number were decreased. Low fertility of founder mice and lethality of young pups did not allow the complete establishment of transgenic lines. To characterize the effect of Notch overexpression in vitro, NICD was induced in osteoblasts and stromal cells from Rosanotch mice, in which a STOP cassette flanked by loxP sites is upstream of NICD, by transduction with an adenoviral vector expressing Cre recombinase (Cre) under the control of the cytomegalovirus (CMV) promoter (Ad-CMV-Cre). NICD impaired osteoblastogenesis and inhibited Wnt/β-catenin signaling. To determine the effects of notch1 deletion in vivo, mice in which notch1 was flanked by loxP sequences (notch1loxP/loxP) were mated with mice expressing Cre recombinase under the control of the osteocalcin promoter. Conditional null notch1 mice had no obvious skeletal phenotype, possibly because of rescue by notch2; however, 1-month-old females exhibited a modest increase in osteoclast surface and eroded surface. Osteoblasts from notch1loxP/loxP mice, transduced with Ad-CMV-Cre and transfected with Notch2 small interfering RNA, displayed increased alkaline phosphatase activity. In conclusion, Notch signaling in osteoblasts causes osteopenia and impairs osteo-blastogenesis by inhibiting the Wnt/β-catenin pathway.


2002 ◽  
Vol 61 (4) ◽  
pp. 1365-1376 ◽  
Author(s):  
Robert Earl Routh ◽  
John Hardwick Johnson ◽  
Kevin John McCarthy

2003 ◽  
Vol 81 (11) ◽  
pp. 1029-1035 ◽  
Author(s):  
Janette Furuzawa-Carballeda ◽  
Emilio Rojas ◽  
Mahara Valverde ◽  
Irma Castillo ◽  
Lino Diaz de León ◽  
...  

Collagen, particularly type I, and its related derivatives have been extensively employed in many areas of pharmacology. The present study was performed to determine the safety of collagen–polyvinylpyrrolidone (collagen–PVP) by in vitro and in vivo studies. Sera and peripheral blood cells from healthy donors without treatment and patients treated with collagen–PVP were evaluated. We observed that the biodrug does not stimulate lymphoproliferation or DNA damage in vitro, nor does it induce human anti-porcine type I collagen or anti-collagen–PVP antibodies in vivo. Furthermore, no hepatic or renal metabolic dysfunctions were observed when collagen–PVP was administered by intradermal or intramuscular routes in short- or long-term treatments. In conclusion, the present work shows that no cellular damage or immunological adverse effects (cellular and humoral) occurred during collagen–PVP treatment, even after more than 400 weeks of consecutive administrations.Key words: collagen–polyvinylpyrrolidone, DNA damage, collagen antibodies, hypertrophic scar.


1982 ◽  
Vol 155 (1) ◽  
pp. 42-51 ◽  
Author(s):  
M L MuÑoz ◽  
J Calderón ◽  
M Rojkind

The present work was designed to investigate the capacity of trophozoites of Entamoeba histolytica to adhere to and digest human collagen types I and III in vitro. The time-course of binding of ameba to both human collagen types I and III was similar. However, the kinetics of detachment were different for each collagen type. Trophozoites of E. histolytica cultured on heat-reconstituted type I collagen gels produced a well-defined area of lysis. Quantitative studies using 14C-labeled collagen revealed that after 24 h of incubation, Entamoeba digested three and a half times more type I than type III collagen, thus suggesting the presence of a collagenase with higher specificity for type I collagen. This activity was optimum with trophozoites harvested after 42 h in culture (1.5 X 10(5) trophozoites/ml). The digestion of type I collagen was a function of the number of trophozoites, and was inhibited by EDTA, L-cysteine, and serum, but not by soybean trypsin inhibitor, phenylmethanesulfonyl fluoride, or N-ethylmaleimide (NEM). Electrophoretic analysis of the type I collagen fragments revealed three main classes of polypeptides of 75,000, 50,000, and 25,000 daltons. Subsequent proteolysis of these collagen fragments was probably carried out by other proteases derived from trophozoites. This activity was inhibited with 10 mM NEM. Collagenase activity appeared to be located at the plasma membrane and direct contact of the ameba with the substrate is required for collagen digestion. The results suggest that collagenase activity of E. histolytica may play an important role in tissue invasion.


1995 ◽  
Vol 269 (3) ◽  
pp. C554-C562 ◽  
Author(s):  
C. J. He ◽  
L. J. Striker ◽  
M. Tsokos ◽  
C. W. Yang ◽  
E. P. Peten ◽  
...  

Changes in the composition of the mesangial extracellular matrix (ECM) and cell turnover are present in glomerular disease. To determine if ECM changes play a role in perpetuating mesangial cell dysfunction, we examined a line of mouse mesangial cells cultured on films or gels of several ECM components and also on methyl cellulose, an inert substrate that prevents attachment. Cells on films of fibronectin or type IV or I collagen had persistently high growth rates and high levels of alpha 1-I and alpha 1-IV collagen mRNAs. In contrast, on gels of type IV or I collagen or matrigel, the growth rate was low. The alpha 1-IV collagen mRNA levels were low on type IV collagen gel or matrigel, whereas the alpha 1-I collagen mRNA levels remained high. In contrast, the alpha 1-I collagen mRNA levels were low on type I collagen gel, and the alpha 1-IV collagen mRNA levels were high. Cells on methyl cellulose formed floating aggregates, did not proliferate, and had a 5- to 10-fold decrease in both alpha 1-I and alpha 1-IV collagen mRNA levels. These phenotypic changes were largely reversible. Finally, when matrigel was layered over cells on fibronectin films, alpha 1-IV collagen mRNA levels decreased, but alpha 1-I collagen mRNA levels and proliferation remained high. Thus proliferation and alpha 1-I and alpha 1-IV collagen mRNA levels in mesangial cells were independently regulated and depended on attachment and the nature of the adjacent matrix.


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