Fibroblast binding

Many cells, including skin fibroblasts, bind and internalize LDL through the LDLR. This opens the possibility of testing the binding capacity of the LDL receptor in cultivated skin fibroblasts of FH patients. The fibroblasts are incubated with radiolabeled LDL and the internalization of the labeled LDL is measured and compared to the internalization of fibroblasts from a normolipidemic donor. 

The rat S-HTja and 5-HT2C receptors were cloned and stably expressed in NIH 3T3 mouse fibroblasts. Binding and competition experiments were performed on membranes prepared from cell cultures using [ I]LSD as radioligand. Inhibition of 5-HT stimulated phosphoinositide hydrolysis was used to determine the antagonistic potencies of the compounds. The agonistic properties of the compounds and their relative efficacies (relative to serotonin that is) were assessed... 

Gailit, J., Clarke, C., Newman, D., Totmesen, M.G., Mosesson, M.W., Clark, R.A., 1997. Human fibroblasts bind directly to fibrinogen at RGD sites through integrin alpha(v)beta3. Exp. Cell Res. 232, 118-126. 

Protease nexin (From cultured human fibroblasts) [148263-58-5], Purified by affinity binding of protease nexin to dextran sulfate-Sepharose. [Farrell et al. Biochem J 237 707 1986.]... 

Stress fibers are parallel bundles of actin filaments that develop in the cytoplasm of fibroblasts from the cortical actin network in response to mechanical tension. These often bind to the plasma membrane at focal contacts and, through transmembrane linker glycoproteins, to the extracellular matrix. Thus, actin filaments of stress fibers indirectly Join to the inner face of the plasma membrane through molecular assemblies of attachment proteins, which include an actin-capping protein, a-actinin, vinculin, and talin (Small, 1988). 

Nagata, K., Saga, S. Yamada, K.M. (1986). A major collagen-binding protein of chick embryo fibroblasts is a novel heat shock protein. Journal of Cell Biology, 103, 223-9. 

In another study, the original repetitive Cio, (AGAGAGPEG)io, center was reconstructed into nine repeats of AGAGAGPEG with three distributed repeats of the RGD sequence. The new triblock protein, composed of acidic and basic terminal domains in addition to the reconstructed central block, has been shown to support adhesion, spreading, and polarization of human fibroblast cells [82]. Triblock polypeptides that facilitate antibody binding have also been reported [83]. 

Burgess WH, Maciag T (1989) The heparin-binding (fibroblast) growth-factor family of proteins. Annu Rev Biochem 58 575-606... 

Man 6-P receptors, located in the Golgi apparatus, bind the Man 6-P residue of these enzymes and direct them to the lysosomes. Fibroblasts from patients with I-cell disease (see below) are severely deficient in the activity of the GIcNAc phosphotransferase. 

Fe-TPAA Fe(III)-tris[N-(2-pyridylmethyl)-2-aminoethyl] amine Fe-TPEN Fe(II)-tetrakis-N,N,N, N -(2-pyridyl methyl-2-aminoethyl)amine FFA Free fatty acids FGF Fibroblast growth factor FID Flame ionization detector FITC Fluorescein isothiocyanate FKBP FK506-binding protein FLAP 5-lipoxygenase-activating protein... 

Phosphofructokinase (PFK) is a key regulatory enzyme of glycolysis that catalyzes the conversion of fructose-6-phosphate to fructose-1,6-diphosphate. The active PFK enzyme is a homo- or heterotetrameric enzyme with a molecular weight of 340,000. Three types of subunits, muscle type (M), liver type (L), and fibroblast (F) or platelet (P) type, exist in human tissues. Human muscle and liver PFKs consist of homotetramers (M4 and L4), whereas red blood cell PFK consists of five tetramers (M4, M3L, M2L2, ML3, and L4). Each isoform is unique with respect to affinity for the substrate fructose-6-phosphate and ATP and modulation by effectors such as citrate, ATP, cAMP, and fructose-2,6-diphosphate. M-type PFK has greater affinity for fructose-6-phosphate than the other isozymes. AMP and fructose-2,6-diphosphate facilitate fructose-6-phosphate binding mainly of L-type PFK, whereas P-type PFK has intermediate properties. 

Adenosine deaminase (ADA) is an amino hydrolase that catalyzes the deamination of adenosine and 2 -deoxyadenosine to inosine and 2 -deoxyinosine, respectively. High activity of ADA is seen in thymus and other lymphoid tissues. ADA has been shown in many different physical forms. A small form of the enzyme predominates in the spleen, stomach, and red blood cells, whereas the large form predominates in the kidney, liver, and skin fibroblasts. The small form of the catalytic subunit can be converted to the large form by complexing with a protein termed binding protein or complexing protein. 

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