scholarly journals Development and characterisation of a low-concentration sodium dodecyl sulphate decellularised porcine dermis

2017 ◽  
Vol 8 ◽  
pp. 204173141772401 ◽  
Author(s):  
Jack A Helliwell ◽  
Daniel S Thomas ◽  
Vaia Papathanasiou ◽  
Shervanthi Homer-Vanniasinkam ◽  
Amisha Desai ◽  
...  

The aim of this study was to adapt a proprietary decellularisation process for human dermis for use with porcine skin. Porcine skin was subject to: sodium chloride (1 M) to detach the epidermis, trypsin paste to remove hair follicles, peracetic acid (0.1% v/v) disinfection, washed in hypotonic buffer and 0.1% (w/v) sodium dodecyl sulphate in the presence of proteinase inhibitors followed by nuclease treatment. Cellular porcine skin, decellularised porcine and human dermis were compared using histology, immunohistochemistry, GSL-1 lectin (alpha-gal epitope) staining, biochemical assays, uniaxial tensile and in vitro cytotoxicity tests. There was no microscopic evidence of cells in decellularised porcine dermis. DNA content was reduced by 98.2% compared to cellular porcine skin. There were no significant differences in the biomechanical parameters studied or evidence of cytotoxicity. The decellularised porcine dermis retained residual alpha-gal epitope. Basement membrane collagen IV immunostaining was lost following decellularisation; however, laminin staining was retained.

Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 533
Author(s):  
Eloy Pena-Rodríguez ◽  
Maria Lajarin-Reinares ◽  
Aida Mata-Ventosa ◽  
Sandra Pérez-Torras ◽  
Francisco Fernández-Campos

Follicular targeting has gained more attention in recent decades, due to the possibility of obtaining a depot effect in topical administration and its potential as a tool to treat hair follicle-related diseases. Lipid core ethyl cellulose lipomers were developed and optimized, following which characterization of their physicochemical properties was carried out. Dexamethasone was encapsulated in the lipomers (size, 115 nm; polydispersity, 0.24; zeta-potential (Z-potential), +30 mV) and their in vitro release profiles against dexamethasone in solution were investigated by vertical diffusion Franz cells. The skin biodistribution of the fluorescent-loaded lipomers was observed using confocal microscopy, demonstrating the accumulation of both lipomers and fluorochromes in the hair follicles of pig skin. To confirm this fact, immunofluorescence of the dexamethasone-loaded lipomers was carried out in pig hair follicles. The anti-inflammatory (via TNFα) efficacy of the dexamethasone-loaded lipomers was demonstrated in vitro in an HEK001 human keratinocytes cell culture and the in vitro cytotoxicity of the nanoformulation was investigated.


1983 ◽  
Vol 59 (1) ◽  
pp. 81-103 ◽  
Author(s):  
R. Crossley ◽  
D.V. Holberton

Proteins from the axonemes and disc cytoskeleton of Giardia lamblia have been examined by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. In addition to tubulin and the 30 X 10(3) molecular weight disc protein, at least 18 minor components copurify with the two major proteins in Triton-insoluble structures. The most prominent minor bands have the apparent molecular weights of 110 X 10(3), 95 X 10(3) and 81 X 10(3). Protein of 30 X 10(3) molecular weight accounts for about 20% of organelle protein on gels. In continuous 25 mM-Tris-glycine buffer it migrates mostly as a close-spaced doublet of polypeptides, which are here given the name giardins. Giardia tubulin and giardin have been purified by gel filtration chromatography in the presence of sodium dodecyl sulphate. Well-separated fractions were obtained that could be further characterized. Both proteins are heterogeneous when examined by isoelectric focusing. Five tubulin chains were detected by PAGE Blue 83 dye-binding after focusing in a broad-range ampholyte gel. Giardin is slightly less acidic than tubulin. On gels it splits into four major and four minor chains with isoelectric points in the pI range from 5.8 to 6.2. The amino acid composition of the giardin fraction has been determined, and compared to Giardia tubulin and a rat brain tubulin standard. Giardins are rich in helix-forming residues, particularly leucine. They have a low content of proline and glycine; therefore they may have extensive alpha-helical regions and be rod-shaped. As integral proteins of disc microribbons, giardins in vivo associate closely with tubulin. The properties of giardins indicate that in a number of respects - molecular size, charge, stoichiometry - their structural interaction with tubulin assemblies will be different from other tubulin-accessory protein copolymers studied in vitro.


1979 ◽  
Vol 184 (2) ◽  
pp. 261-267 ◽  
Author(s):  
R K Craig ◽  
P A J Perera ◽  
A Mellor ◽  
A E Smith

1. Guinea-pig caseins synthesized in a mRNA-directed wheat-germ cell-free protein-synthesizing system represent the primary translation products, even though they appear to be of lower molecular weight when analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis in parallel with caseins isolated from guinea-pig milk. 2. Identification of the N-terminal dipeptide of the primary translational product of caseins A, B and C and alpha-lactalbumin showed that all shared a common sequence, which was identified as either Met-Arg or Met-Lys. 3. Procedures utilizing methionyl-tRNAfMet or methionyl-tRNAMet in the presence or absence of microsomal membranes during translation provide a rapid method of distinguishing between N-terminal processing of peptides synthesized in vitro and other post-translational modifications (glycosylation, phosphorylation), which also result in a change in mobility of peptides when analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. 4. The results demonstrate that guinea-pig caseins, in common with most other secretory proteins, are synthesized with transient N-terminal ‘signal’-peptide extensions, which are cleaved during synthesis in the presence of microsomal membranes.


1982 ◽  
Vol 203 (3) ◽  
pp. 593-601 ◽  
Author(s):  
C Lafuma ◽  
M Moczar ◽  
L Robert

1. Glycoproteins of hamster, rat and baboon lung parenchyma were investigated by using [14C]glucosamine incorporation in vitro followed by sequential extraction of the macromolecular components and characterization of the glycoproteins in the extracts. 2. Slices of lung parenchyma maintained in vitro incorporated [U-14C]glucosamine linearly with time into non-diffusible macromolecules for up to 5h. All the macromolecule-associated 14C label was present as [14C]glucosamine. 3. These 14C-labelled macromolecules were extracted from previously delipidated and salt-extracted lung by 5M-guanidinium chloride in the presence of dithiothreitol and proteinase inhibitors before (extract A1) and after (extract A2) hydrolysis of the collagen by collagenase. The [14C]glucosamine-labelled glycoproteins in extracts A1 and A2 contained 55 and 5% respectively of the total [14C]glucosamine incorporated in the lung of all three species studied. 4. The [14C]glucosamine-labelled glycoproteins were analysed by gel-filtration chromatography, sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and isoelectric focusing. The major [14C]glucosamine-labelled glycoproteins of baboon lung parenchyma had apparent mol.wts. of about 400 000, 140 000 and 65 000 with isoelectric points respectively of 4.8, 5.4 and 5.4. The hamster lung glycoproteins with isoelectric points of 4.1 and 5.8 were devoid of hydroxyproline and contained galactose, mannose and N-acetylglucosamine. These experiments indicate that several distinct glycoproteins are synthesized in situ by the cells of pulmonary parenchyma and may well play a role in its structure and function.


1985 ◽  
Vol 228 (3) ◽  
pp. 551-556 ◽  
Author(s):  
G W Dombi ◽  
H B Halsall

Sodium dodecyl sulphate (SDS) was used to weaken both the electrostatic and the hydrophobic interactions during collagen fibrillogenesis in vitro. The rate and extent of fibril formation as well as fibril morphology were affected by SDS concentration. Both the formation of large fibrils at 0.3 mM-SDS and the complete cessation of fibril formation at 0.5 mM-SDS were considered to be the result of SDS-induced conformational changes in the non-helical telopeptides. A possible mechanism of SDS interaction with the N-terminal and the distal region of the C-terminal telopeptides is offered.


1975 ◽  
Vol 149 (1) ◽  
pp. 39-48 ◽  
Author(s):  
P M Steinert

1. The α-fibrous protein (α-keratin) component of bovine epidermis has been extracted and characterized. 2. Prekeratin, a multichain unit of the epidermal tonofilaments, was shown to consist of six different polypeptide chains on polyacrylamide-gel systems containing sodium dodecyl sulphate or sodium decyl sulphate with discontinuous gel buffers, but only three chains were seen when a gel system containing sodium dodecyl sulphate with a continuous gel buffer was used. 3. Extraction of the ‘keratinized’ stratum corneum and the living part of the epidermis with urea buffers at pH 7.6 or 9.0 released 60% of the total dry weight of the tissues in the form of α-helical polypeptides. 4. The numbers, relative amounts and properties of the extracted polypeptides were the same as the subunits of prekeratin and thus are derived from the tonofilaments in situ. 5. The subunits of prekeratin and the polypeptides extracted from the living cell layers contained an average of six cysteine residues, but those from the stratum corneum contained an average of three intrachain disulphide bonds. 6. The polypeptide chains aggregated through non-covalent interactions in vitro into filaments that were similar to the tonofilaments. 7. Since the polypeptides could be released from the stratum corneum without breaking covalent bonds, it is concluded that such bonds do not cross-link the tonofilaments and non-fibrous keratohyalin. It is suggested that the tonofilaments and keratohyalin of bovine epidermis are associated by secondary bonding forces.


1977 ◽  
Vol 165 (1) ◽  
pp. 111-119 ◽  
Author(s):  
L Moens ◽  
M Kondo

The following factors were measured for extracellular haemoglobins of Artemia salina: a minimal molecular weight of globin chain per haem group (based on the iron and haem contents), the absorption coefficients, the absorption spectra of various derivatives and the amino acid compositions. These were compared with those of the haemoglobins of other invertebrates. Three Artemia haemoglobins (I, II and III) had similar molecular structures, constructed from two-globin subunits of 122000-130000mol.wt. Since the minimal mol.wt. was determined to be 18000, this suggests that one globin subunit was bound by seven haem groups, and hence one haemoglobin molecule (240000-260000mol.wt.) should contain 14 haem groups. A successful identification of this high-molecular-weight subunit required first the denaturation of haemoglobin in 1% sodium dodecyl sulphate before sodium dodecyl sulphate gel electrophoresis. Denaturation by prolonged incubation (12-36 h) at room temperature in the presence of 0.1% sodium dodecyl sulphate [Bowen, Moise, Waring & Poon (1976) Comp. Biochem. Physiol. B55, 99-103] was accompanied by extensive proteolysis, resulting in low recovery of the stainable protein and heterogeneous gel patterns. Regardless of which electrophoretic system was used, the high-molecular-weight subunit was always present provided that 1% sodium dodecyl sulphate was present during denaturation. These results contrast with those obtained by Bowen et al. (1976). However, preferential cleavage of the globin subunit (alpha) seemed to occur in vitro when standard conditions were used, producing two specific fragments having mol.wts. of 80000 (beta) and 50000 (gamma).


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