scholarly journals Molecular composition of type VI collagen. Evidence for chain heterogeneity in mammalian tissues and cultured cells

1990 ◽  
Vol 272 (3) ◽  
pp. 787-795 ◽  
Author(s):  
C M Kielty ◽  
R P Boot-Handford ◽  
S Ayad ◽  
C A Shuttleworth ◽  
M E Grant
Keyword(s):  
Cultured Cells ◽  
Phenotypic Change ◽  
Quiescent State ◽  
Collagen Vi ◽  
Type Vi Collagen ◽  
Foetal Development ◽  
Chain Composition ◽  
Cell Layers ◽  
A Chain ◽  
Nuchal Ligament

The chain composition and relative abundance of type VI collagen synthesized by cells cultured from foetal bovine nuchal ligament and skin were compared with those of the type VI collagen present in these foetal tissues. Immunoprecipitation of intact collagen VI from medium and cell layers of nuchal ligament fibroblasts and skin fibroblasts at confluence revealed collagen type VI molecules with a chain composition consistent with an [alpha 1(VI)alpha 2(VI)alpha 3(VI)] monomeric assembly. Maintenance of cells in a post-confluent quiescent state promoted a marked phenotypic change in these ratios, with increased concentrations of assemblies composed of equimolar ratios of alpha 1(VI) and alpha 2(VI) chains detected in the medium of these cultures. Analysis of steady-state concentrations of mRNA for alpha 1(VI) and alpha 2(VI) chains revealed these species to be present in increased abundance at post-confluence in all the cultures, but no corresponding increase was observed in the alpha 3(VI) mRNA. In order to assess the physiological significance of these observations, the chain composition of the collagen VI content of the corresponding foetal tissues was assessed by Western blotting after extraction in guanidinium isothiocyanate under reducing conditions. Extracts of nuchal ligament revealed a collagen VI chain composition consistent with a heterotrimeric chain assembly. In contrast, the skin extracts revealed an abundance of alpha 1(VI) and alpha 2(VI) chains with only traces of the alpha 3(VI) chain detected. Increased equimolar concentrations of the alpha 1(VI)-chain and alpha 2(VI)-chain mRNAs in skin again reflected the increased concentrations of these polypeptide chains. Type VI collagen was present in greater abundance both in the nuchal ligament and in the corresponding nuchal-ligament fibroblast cultures. The results indicate that the chain composition of type VI collagen is subject to modulation at the level of transcription as a result of variations in the proliferative state of the cells, and demonstrate that different isoforms of collagen VI occur in foetal development.

Isolation and ultrastructural analysis of microfibrillar structures from foetal bovine elastic tissues. Relative abundance and supramolecular architecture of type VI collagen assemblies and fibrillin

1991 ◽  
Vol 99 (4) ◽  
pp. 797-807
Author(s):  
C.M. Kielty ◽  
C. Cummings ◽  
S.P. Whittaker ◽  
C.A. Shuttleworth ◽  
M.E. Grant
Keyword(s):  
Relative Abundance ◽  
Gel Filtration ◽  
Supramolecular Architecture ◽  
Collagen Vi ◽  
Type Vi Collagen ◽  
Bacterial Collagenase ◽  
New Information ◽  
Sds Page ◽  
Complex Polymers ◽  
Nuchal Ligament

Extensive intact assemblies of matrix macromolecules have been solubilized from foetal calf skin, nuchal ligament and aorta by a new procedure that includes bacterial collagenase digestion under non-reducing, non-denaturing conditions and gel filtration chromatography. Type VI collagen was identified as the major microfibrillar element of these tissues by SDS-PAGE analysis and Western blotting. Rotary shadowing electron microscopy of these preparations revealed by far the most abundant and extensive arrays of intact collagen VI microfibrils isolated to date. The distinct microfibrillar species, fibrillin, which was identified on the basis of its periodicity and morphology, was also solubilized in abundance by this protocol. Analysis of these complex polymers has generated new information on their supramolecular architecture and relative abundance in these tissues. The protocol also demonstrates that the release of intact collagen VI microfibrils from these tissues is largely dependent on the removal of the major collagen fibrils.

scholarly journals Alterations in the phenotype of hairy cells during culture in the presence of PHA: requirement for T cells

Blood ◽  
1982 ◽  
Vol 59 (5) ◽  
pp. 895-899 ◽  
Author(s):  
CP Worman ◽  
PC Beverley ◽  
JC Cawley
Keyword(s):  
T Cells ◽  
Hairy Cell Leukemia ◽  
Mononuclear Cells ◽  
Cultured Cells ◽  
Phenotypic Change ◽  
Cell Contact ◽  
Hairy Cell ◽  
Cell Leukemia ◽  
Peripheral Blood Mononuclear ◽  
Hairy Cells

Abstract Culture studies of peripheral blood mononuclear cells from 7 entirely typical cases of hairy cell leukemia showed that after culture in the presence of PHA for 2--5 days, the predominant cell type changed from E- SIg+ CIg+ gamma FcR+ muFcR+ hairy cells to an E+ SIg- CIg- gamma FcR- muFcR- population of transformed cells derived from hairy cells. Depletion and readdition experiments demonstrated that cell-to-cell contact with T cells was necessary for the phenotypic change, while several observations indicated that the E+ population was not derived from T cells present before culture. The E positivity of the cultured cells was shown to be due to the possession of E receptor not acquired from the culture fluid, but the cells differed from true T cells in lacking both mature and immature T-cell antigens. The relevance of these in vitro observations to the continuing controversy concerning the nature of the hairy cell and to the in vivo fluctuations in immunologic phenotype not infrequently observed in hairy cell leukemia is briefly discussed.

scholarly journals Antifibrotic effect of Pluchea sagitallis (Lam.) cabrera aqueous extract in grx cell lineage

2018 ◽  
Vol 10 (1) ◽  
pp. 30
Author(s):  
Fabiana Garbachi De Oliveira Mendes Ouri ◽  
Paula Bacaicoa Caruso ◽  
Gabriela Viegas Da Silva ◽  
Henrique Dias ◽  
Juliana Romeu Marques ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Lipid Content ◽  
Complex Disease ◽  
Stellate Cell ◽  
Normal Liver ◽  
Phenotypic Change ◽  
Quiescent State ◽  
Antifibrotic Effect ◽  
Significant Difference

<p>Liver fibrosis is a complex disease that is caused by inappropriate tissue repair due to the deposition of connective tissue. When a chronic lesion affects the liver, regenerative response fails and hepatocytes are replaced with abundant extracellular matrix (ECM). The imbalance between production and degradation of ECM will result in the accumulation of proteins that change normal liver architecture, and thus its functionality. The main source of ECM is the activated hepatic stellate cell (HSC). In order, to clarify possible therapeutic approaches to the disease, this work aimed to evaluate the possible antifibrotic action of <em>Pluchea sagitallis </em>(Lam.) Cabrera on an activated HSC immortalized lineage (GRX).</p><p>Our results demonstrated that the <em>P. sagittalis</em> aqueous extract at 0.039 and 0.078 mg/mL concentrations was able to reduce cell growth and proliferation. Regarding to oxidative stress evaluation, there was no statistically significant difference between the treated group and the control. Staining with OilRed-O (ORO) showed a statistically significant increase in intracellular lipid content after 5 days of treatment, exerting <em>in vitro</em> effect on the GRX phenotypic change of activated towards the quiescent state. These results were confirmed by colorimetric quantification of lipid content. Regarding the TGF-β1 and collagen production, there were no statistically significant differences observed between the groups.</p><p>In conclusion, the <em>P. sagittalis</em> aqueous extract reduces the growth and proliferation of GRX cells and induces the reversal of activated towards a quiescent phenotype. There was no decrease in cell proliferation either by necrosis or by apoptosis via activation of the senescence. Thus, our data suggest that the extract showed an antifibrotic effect, possibly by activating phenotype reversal.</p>

STEM mass mapping of type VI collagen microfibrils: Implications for chain composition and alternative splicing

1999 ◽  
Vol 111 (1) ◽  
pp. 147-157
Author(s):  
Stephen G Ball ◽  
Karen Johnston ◽  
Cay M Kielty ◽  
C Adrian Shuttleworth
Keyword(s):  
Alternative Splicing ◽  
Type Vi Collagen ◽  
Chain Composition ◽  
Mass Mapping

scholarly journals Platelet adhesion and aggregation on human type VI collagen surfaces under physiological flow conditions

Blood ◽  
1995 ◽  
Vol 85 (7) ◽  
pp. 1826-1835 ◽  
Author(s):  
JM Ross ◽  
LV McIntire ◽  
JL Moake ◽  
JH Rand
Keyword(s):  
Shear Rate ◽  
Platelet Adhesion ◽  
Surface Coverage ◽  
Wall Shear Rate ◽  
Flow Conditions ◽  
Collagen Vi ◽  
Type Vi Collagen ◽  
Platelet Adhesion And Aggregation ◽  
Von Willebrand ◽  
Low Shear

Type VI collagen is a subendothelial constituent that binds von Willebrand factor (vWF) and platelets. The interaction of platelets with type VI collagen and the roles of platelet glycoprotein (GP) receptors and vWF were studied under flow conditions using epi-fluorescent videomicroscopy coupled with digital image processing. We found that surface coverage was less than 6% on collagen VI at a relatively high-wall shear rate (1,000 s-1) and was approximately 60% at a low-wall shear rate (100 s-1). The molecular mechanisms involved in low-shear platelet binding were studied using monoclonal antibodies to platelet GPIb and GPIIb-IIIa, and polymeric aurin tricarboxylic acid. Anti-GPIIb-IIIa was the most effective in eliminating adhesion (surface coverage, 0.8%), followed by anti-GPIb (4.3%), and ATA (12.6%). Experiments with von Willebrand disease blood indicate that vWF is involved in platelet adhesion to collagen VI at 100 s-1. In the absence of vWF, there may be direct binding of platelet GPIIb-IIIa complexes to collagen VI. Adhesion and aggregation on collagen VI are different in shear rate dependence from collagen I. Our results suggest a possible role for collagen VI and vWF in platelet adhesion and aggregation in vascular regions with low shear rates.

scholarly journals Developmental regulation of the mRNAs for elastins a, b and c in foetal-calf nuchal ligament and aorta

1989 ◽  
Vol 261 (1) ◽  
pp. 227-232 ◽  
Author(s):  
R P Paulovic ◽  
R A Anwar
Keyword(s):  
Developmental Regulation ◽  
Developmentally Regulated ◽  
Foetal Development ◽  
Tissue Specific ◽  
Nuchal Ligament ◽  
Self Aggregation

The data presented clearly suggest that relative amounts of mRNAs for elastins a, b and c are developmentally regulated in foetal-calf nuchal ligament and aorta and that this regulation is tissue-specific. In nuchal ligament, at earlier stages of foetal development, the relative amounts of mRNAs for elastins a and b are very low. After the foetal age of about 6 months the relative amount of mRNA for elastin b begins to increase. This is followed by an increase in the relative amount of mRNA for elastin a. In aorta, with increasing foetal age, the relative amounts of mRNAs for elastins b and c increase and decrease alternately. The relative amounts of mRNA for elastin a remain low, with only marginal increases with foetal age. A possible self-aggregation role of elastin a in elastogenesis is proposed.

scholarly journals Secretion and Assembly of Type IV and VI Collagens Depend on Glycosylation of Hydroxylysines

2007 ◽  
Vol 282 (46) ◽  
pp. 33381-33388 ◽  
Author(s):  
Laura Sipilä ◽  
Heli Ruotsalainen ◽  
Raija Sormunen ◽  
Naomi L. Baker ◽  
Shireen R. Lamandé ◽  
...  
Keyword(s):  
Congenital Muscular Dystrophy ◽  
Basement Membranes ◽  
Collagen Vi ◽  
Collagen Types ◽  
Type Vi Collagen ◽  
Knock Out ◽  
Type Iv ◽  
New Information ◽  
Ullrich Congenital Muscular Dystrophy

Most lysines in type IV and VI collagens are hydroxylated and glycosylated, but the functions of these unique galactosylhydroxylysyl and glucosylgalactosylhydroxylysyl residues are poorly understood. The formation of glycosylated hydroxylysines is catalyzed by multifunctional lysyl hydroxylase 3 (LH3) in vivo, and we have used LH3-manipulated mice and cells as models to study the function of these carbohydrates. These hydroxylysine-linked carbohydrates were shown recently to be indispensable for the formation of basement membranes (Ruotsalainen, H., Sipilä, L., Vapola, M., Sormunen, R., Salo, A. M., Uitto, L., Mercer, D. K., Robins, S. P., Risteli, M., Aszodi, A., Fässler, R., and Myllylä, R. (2006) J. Cell Sci. 119, 625–635). Analysis of LH3 knock-out embryos and cells in this work indicated that loss of glycosylated hydroxylysines prevents the intracellular tetramerization of type VI collagen and leads to impaired secretion of type IV and VI collagens. Mice lacking the LH activity of LH3 produced slightly underglycosylated type IV and VI collagens with abnormal distribution. The altered distribution and aggregation of type VI collagen led to similar ultrastructural alterations in muscle to those detected in collagen VI knockout and some Ullrich congenital muscular dystrophy patients. Our results provide new information about the function of hydroxylysine-linked carbohydrates of collagens, indicating that they play an important role in the secretion, assembly, and distribution of highly glycosylated collagen types.

scholarly journals Elastin mRNA levels during foetal development of sheep nuchal ligament and lung. Hybridization to complementary and cloned DNA

1984 ◽  
Vol 220 (3) ◽  
pp. 653-663 ◽  
Author(s):  
J M Davidson ◽  
S Shibahara ◽  
C Boyd ◽  
M L Mason ◽  
P Tolstoshev ◽  
...  
Keyword(s):  
Cdna Probe ◽  
Northern Analysis ◽  
Northern Hybridization ◽  
Mrna Levels ◽  
Foetal Development ◽  
Total Rna ◽  
Mrna Content ◽  
Near Term ◽  
Nuchal Ligament ◽  
Elastin Gene

Elastin mRNA levels were quantified in sheep nuchal ligament and lung during the latter half of foetal development with elastin-specific cDNA (complementary DNA) probes using both hybridization in solution (saturation analysis) and hybridization on a fixed support (Northern analysis). For the solution-hybridization studies, cDNA prepared from nuchal-ligament mRNA was enriched to 65% for elastin sequences by hybridizing it to its template at a R0t (mol X s X litre-1) value that included only the abundant class of mRNA sequences. Hybridization of this probe to RNA extracted from nuchal ligament between 70 and 138 days after conception demonstrated elastin sequences increased about 10-fold (from 0.047 to 0.438% of total RNA). In contrast, lung elastin mRNA levels increased only 3-fold (from 0.009 to 0.022% of total RNA) during the same period. Over this development period these values correspond to increases in the average number of elastin mRNA molecules from 950 to 20 000 molecules/ligament cell and from 130 to 330 molecules/lung cell. For Northern analysis, elastin mRNA was purified from near-term-sheep nuchal ligament on sucrose density gradients. Analysis of the translation products of this elastin mRNA showed that relative elastin precursor synthesis was at least 80% of total [3H]valine incorporation. The Mr of this elastin mRNA, determined by methylmercury-agarose-gel electrophoresis, was approx. 1.25 × 10(6). Northern hybridization of nuchal ligament and lung RNA to a [32P]cDNA probe, transcribed from this sucrose-gradient-purified elastin mRNA, confirmed the developmental changes in elastin mRNA levels detected by solution-hybridization techniques. The specificity of this method was confirmed by using a cloned elastin gene fragment. These studies demonstrate that elastin mRNA levels in organs such as nuchal ligament and lung increase with foetal development, but that there are significant differences in the average cellular elastin mRNA content of these two organs.

scholarly journals Differential effects of nitrated ricin and nitrated and dithionite-reduced ricin on protein-synthesis inhibition and transmembrane tramsport in eukaryotic cells

1980 ◽  
Vol 188 (3) ◽  
pp. 941-944 ◽  
Author(s):  
P N Dalrymple ◽  
L L Houston
Keyword(s):  
Protein Synthesis ◽  
Cell Surface ◽  
Indirect Immunofluorescence ◽  
Cultured Cells ◽  
Sodium Dithionite ◽  
Eukaryotic Cells ◽  
Protein Synthesis Inhibition ◽  
Inhibiting Protein ◽  
A Chain

Ricin, was nitrated with tetranitromethane and reduced with sodium dithionite. Of the 8.0 nitro groups incorporated, 3.2 were on the A chain and 5.1 were on the B chain. Nitrated ricin1 was somewhat less active than nitrated and reduced ricin1 in inhibiting protein synthesis in vitro, but both were highly inhibitory. However, the modified toxins were less than 1% as active as ricin in inhibiting protein synthesis in cultured cells. Indirect immunofluorescence assays demonstrated tha both modified toxins were specifically bound to the cell surface and could be displaced by galactose.

scholarly journals Alterations in the phenotype of hairy cells during culture in the presence of PHA: requirement for T cells

Blood ◽  
1982 ◽  
Vol 59 (5) ◽  
pp. 895-899 ◽  
Author(s):  
CP Worman ◽  
PC Beverley ◽  
JC Cawley
Keyword(s):  
T Cells ◽  
Hairy Cell Leukemia ◽  
Mononuclear Cells ◽  
Cultured Cells ◽  
Phenotypic Change ◽  
Cell Contact ◽  
Hairy Cell ◽  
Cell Leukemia ◽  
Peripheral Blood Mononuclear ◽  
Hairy Cells

Culture studies of peripheral blood mononuclear cells from 7 entirely typical cases of hairy cell leukemia showed that after culture in the presence of PHA for 2--5 days, the predominant cell type changed from E- SIg+ CIg+ gamma FcR+ muFcR+ hairy cells to an E+ SIg- CIg- gamma FcR- muFcR- population of transformed cells derived from hairy cells. Depletion and readdition experiments demonstrated that cell-to-cell contact with T cells was necessary for the phenotypic change, while several observations indicated that the E+ population was not derived from T cells present before culture. The E positivity of the cultured cells was shown to be due to the possession of E receptor not acquired from the culture fluid, but the cells differed from true T cells in lacking both mature and immature T-cell antigens. The relevance of these in vitro observations to the continuing controversy concerning the nature of the hairy cell and to the in vivo fluctuations in immunologic phenotype not infrequently observed in hairy cell leukemia is briefly discussed.

Sign in / Sign up

Export Citation Format

Share Document