scholarly journals COLLECT EXTRACELLULAR MATRIX FROM IN VITRO FIBROBLAST

2009 ◽  
Vol 12 (9) ◽  
pp. 5-11
Author(s):  
Giang Thi Thanh Nguyen ◽  
Quan Minh To ◽  
Ngoc Kim Phan ◽  
Ha Le Bao Tran

Extracellular matrices (ECM) have been reported to enhance cell attachment and proliferation as well as to create stem cell niches invitro. We harvested ECM from human fibroblasts for a number of researches, including tissue engineering. Fibroblasts were isolated from human foreskins, cultured in DMEMF12 containing 10% FBS and identified by Trichrome staining and immunohistochemistry for Vimentin. Then, fibroblasts were stimulated to synthetize ECM in medium supplemented 0.05% ascorbic acid. Cell constituents were removed by using Triton X-100, NH4OH and DNAse. ECM proteins were evaluated by PAS staining. Results showed that collagen is present in ECM.

MRS Advances ◽  
2019 ◽  
Vol 5 (12-13) ◽  
pp. 609-620
Author(s):  
Thanga Bhuvanesh ◽  
Rainhard Machatschek ◽  
Yue Liu ◽  
Nan Ma ◽  
Andreas Lendlein

ABSTRACTFibronectin (FN) is a mediator molecule, which can connect cell receptors to the extracellular matrix (ECM) in tissues. This function is highly desirable for biomaterial surfaces in order to support cell adhesion. Controlling the fibronectin adsorption profile on substrates is challenging because of possible conformational changes after deposition, or due to displacement by secondary proteins from the culture medium. Here, we aim to develop a method to realize self-stabilized ECM glycoprotein layers with preserved native secondary structure on substrates. Our concept is the assembly of FN layers at the air-water (A-W) interface by spreading FN solution as droplets on the interface and transfer of the layer by the Langmuir-Schäfer (LS) method onto a substrate. It is hypothesized that 2D confinement and high local concentration at A-W interface supports FN self-interlinking to form cohesive films. Rising surface pressure with time, plateauing at 10.5 mN·m-1 (after 10 hrs), indicated that FN was self-assembling at the A-W interface. In situ polarization-modulation infrared reflection absorption spectroscopy of the layer revealed that FN maintained its native anti-parallel β-sheet structure after adsorption at the A-W interface. FN self-interlinking and elasticity was shown by the increase in elastic modulus and loss modulus with time using interfacial rheology. A network-like structure of FN films formed at the A-W interface was confirmed by atomic force microscopy after LS transfer onto Si-wafer. FN films consisted of native, globular FN molecules self-stabilized by intermolecular interactions at the A-W interface. Therefore, the facile FN self-stabilized network-like films with native anti-parallel β-sheet structure produced here, could serve as stable ECM protein coatings to enhance cell attachment on in vitro cell culture substrates and planar implant materials.


2019 ◽  
Vol 476 (24) ◽  
pp. 3835-3847 ◽  
Author(s):  
Aliyath Susmitha ◽  
Kesavan Madhavan Nampoothiri ◽  
Harsha Bajaj

Most Gram-positive bacteria contain a membrane-bound transpeptidase known as sortase which covalently incorporates the surface proteins on to the cell wall. The sortase-displayed protein structures are involved in cell attachment, nutrient uptake and aerial hyphae formation. Among the six classes of sortase (A–F), sortase A of S. aureus is the well-characterized housekeeping enzyme considered as an ideal drug target and a valuable biochemical reagent for protein engineering. Similar to SrtA, class E sortase in GC rich bacteria plays a housekeeping role which is not studied extensively. However, C. glutamicum ATCC 13032, an industrially important organism known for amino acid production, carries a single putative sortase (NCgl2838) gene but neither in vitro peptide cleavage activity nor biochemical characterizations have been investigated. Here, we identified that the gene is having a sortase activity and analyzed its structural similarity with Cd-SrtF. The purified enzyme showed a greater affinity toward LAXTG substrate with a calculated KM of 12 ± 1 µM, one of the highest affinities reported for this class of enzyme. Moreover, site-directed mutation studies were carried to ascertain the structure functional relationship of Cg-SrtE and all these are new findings which will enable us to perceive exciting protein engineering applications with this class of enzyme from a non-pathogenic microbe.


2011 ◽  
Vol 81 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Joel Deneau ◽  
Taufeeq Ahmed ◽  
Roger Blotsky ◽  
Krzysztof Bojanowski

Type II diabetes is a metabolic disease mediated through multiple molecular pathways. Here, we report anti-diabetic effect of a standardized isolate from a fossil material - a mineraloid leonardite - in in vitro tests and in genetically diabetic mice. The mineraloid isolate stimulated mitochondrial metabolism in human fibroblasts and this stimulation correlated with enhanced expression of genes coding for mitochondrial proteins such as ATP synthases and ribosomal protein precursors, as measured by DNA microarrays. In the diabetic animal model, consumption of the Totala isolate resulted in decreased weight gain, blood glucose, and glycated hemoglobin. To our best knowledge, this is the first description ever of a fossil material having anti-diabetic activity in pre-clinical models.


Diabetes ◽  
1989 ◽  
Vol 38 (8) ◽  
pp. 1036-1041 ◽  
Author(s):  
J. A. Vinson ◽  
M. E. Staretz ◽  
P. Bose ◽  
H. M. Kassm ◽  
B. S. Basalyga
Keyword(s):  

2017 ◽  
Vol 2 (3) ◽  
pp. 150-163
Author(s):  
Ekajayanti Kining ◽  
Syamsul Falah ◽  
Novik Nurhidayat

Pseudomonas aeruginosa is one of opportunistic pathogen forming bacterial biofilm. The biofilm sustains the bacterial survival and infections. This study aimed to assess the activity of water extract of papaya leaves on inhibition of cells attachment, growth and degradation of the biofilm using crystal violet (CV) biofilm assay. Research results showed that water extract of papaya leaves contains alkaloids, tanins, flavonoids, and steroids/terpenoids and showed antibacterial activity and antibiofilm against P. aeruginosa. Addition of extract can inhibit the cell attachment and was able to degrade the biofilm of 40.92% and 48.058% respectively at optimum conditions: extract concentration of 25% (v/v), temperature 37.5 °C and contact time 45 minutes. With a concentration of 25% (v/v), temperature of 50 °C and the contact time of 3 days, extract of papaya leaves can inhibit the growth of biofilms of 39.837% v/v.


2020 ◽  
Vol 51 (4) ◽  
pp. 1038-1047
Author(s):  
Mawia & et al.

This study had as principal objective identification of osmotic-tolerant potato genotypes by using "in vitro" tissue culture and sorbitol as a stimulating agent, to induce water stress, which was added to the  culture nutritive medium in different concentration (0,50, 110, 220, 330 and 440 mM).  The starting point was represented by plantlets culture collection, belonging to eleven potato genotypes: Barcelona, Nectar, Alison, Jelly, Malice, Nazca, Toronto, Farida, Fabulla, Colomba and Spunta. Plantlets were multiplied between two internodes to obtain microcuttings (in sterile condition), which were inoculated on medium. Sorbitol-induced osmotic stress caused a significant reduction in the ascorbic acid, while the concentration of proline, H2O2 and solutes leakage increased compared with the control. Increased the proline content prevented lipid peroxidation, which played a pivotal role in the maintenance of membrane integrity under osmotic stress conditions. The extent of the cytoplasmic membrane damage depends on osmotic stress severity and the genotypic variation in the maintenance of membranes stability was highly associated with the ability of producing more amounts of osmoprotectants (proline) and the non-enzymic antioxidant ascorbic acid in response to osmotic stress level. The results showed that the genotypes Jelly, Nectar, Allison, Toronto, and Colomba are classified as highly osmotic stress tolerant genotypes, while the genotypes Nazca and Farida are classified as osmotic stress susceptible ones.


Blood ◽  
1992 ◽  
Vol 80 (9) ◽  
pp. 2246-2251 ◽  
Author(s):  
JG Kelton ◽  
TE Warkentin ◽  
CP Hayward ◽  
WG Murphy ◽  
JC Moore

Abstract Thrombotic thrombocytopenic purpura (TTP) is characterized by thrombocytopenia and disseminated platelet thrombi throughout the microvasculature. Studies by our group have demonstrated calcium- dependent proteolytic activity (calpain) that is no longer detectable in the serum of patients with acute TTP after their recovery. The purpose of this study was to investigate if the protease activity of TTP was detectable in plasma and, therefore, not an in vitro phenomenon secondary to the formation of serum. Additionally, we looked for evidence of membrane association of the active protease in the patients' samples, which would explain the persistence of its activity in the presence of plasma inhibitors. Acute TTP samples, both serum and plasma, were collected from 10 patients with TTP. Calpain was measured using bioassays for enzyme activity and also by detection of the protein using immunoblotting with an anticalpain monoclonal antibody (MoAb). In all instances, calpain could be detected both functionally and antigenically in the acute TTP sera and plasma. No calpain activity could be detected in any of the controls, although antigenic calpain was detectable in one sample from a patient who had undergone cardiopulmonary bypass surgery. To investigate whether the calpain was associated with microparticles in the plasma, the TTP plasma samples were ultrafiltered and ultracentrifuged. Activity was not lost by passage across a 0.2-micron filter but was detectable only in the pellet following ultracentrifugation. Membrane association of the calpain in the microparticles also was demonstrated using solubilization with Triton X-100. Immunoprecipitation studies demonstrated that the calpain activity could be removed by MoAbs against platelet membrane glycoproteins (IX and IIb/IIa) but not by a MoAb against red blood cell membrane glycophorin. These studies indicate that active calpain is associated with platelet microparticles in plasma from patients with TTP.


Blood ◽  
1981 ◽  
Vol 58 (2) ◽  
pp. 350-353 ◽  
Author(s):  
JH Joist ◽  
RK Baker

Abstract We previously demonstrated that platelets can be labeled with 111Inoxine with high labeling efficiency and that 111In is not liberated from labeled platelets during the platelet release reaction or prolonged in vitro storage. In view of these findings, we examined the potential usefulness of loss of 111In from labeled platelets as an indicator or platelet damage by comparing the loss of 111In with that of 51Cr and LDH (in some experiments also with platelet factor 3 availability) under different conditions of platelet injury. When washed human platelets labeled with either 51Cr-chromate or 111In-oxine were exposed to increasing concentrations of detergents (Triton X-100, lysolecithin), threshold, rate, and extent of loss of 111In, 51Cr and, LDH were similar. In contrast, when labeled platelets were depleted of metabolic energy by incubation in glucose-free Tyrode albumin solution or glucose-depleted plasma in the presence of antimycin A and 2-deoxy-D- glucose, loss of 51Cr (and PF3a) occurred earlier and progressed at a faster rate than that of 111In or LDH. Similar results were obtained when platelets were exposed to increasing concentrations of PlA1 antibody, causing complement-mediated immune injury. The findings indicate that with certain agents that cause rapid platelet disruption (lysis), different platelet constituents are lost at similar rates. However, under conditions of more subtle or slowly progressive platelet injury, small molecules such as adenine nucleotides (51Cr) may escape earlier and at faster rates than larger molecules such as LDH or 111In- binding platelet protein. Thus, neither 111In loss nor LDH loss appear to be suitable indicators for sublytic or prelytic platelet injury.


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