In this paper, a stability-based unicast routing mechanism, that considers both link affinity and path stability in order to find out a stable route from source to destination, is proposed.
This interpretation is supported by data linking affinity for albumin with the biocompatibility of biomaterials used in variety of medical applications (dialysis, vascular grafting, tissue scaffolding, etc) [48], and the theoretical model describing albumin and other non-defense proteins as tissue-reactivity silencers [49].
Gels were fixed (1 hour, 10%HAc/300% MeOH) at room temperature and dried, and [I]TGF-β cross-link affinity labeled proteins were imaged using a PhosphorImager 401E and analyzed using ImageQuant software (both purchased from Molecular Dynamics, Sunnyvale, CA, USA).
The identity of the type II and III TGF-β receptors was confirmed by immunoprecipitation of the [I]TGF-β1 cross-link affinity labeled receptors, using specific antibodies (data not shown).
In order to collapse the type III receptor into a tighter band and thereby enhance our ability to detect it at the cell surface, we treated the three cell lines with heparinitase I, II and III, and chondroitinase ABC before cross-link affinity labeling with [I]TGF-β1 or [I]TGF-β2 (Fig. 3e, bottom panels).
The next day, cells were cross-link affinity labeled with 100 pmol/l [I]TGF-β1 (NEN-Life Science Products) or [I]TGF-β2 (iodination according to Philip and O'Connor-McCourt [ 32]) in the absence or presence of 100× excess unlabeled TGF-β1 in 300 μl binding buffer (D-PBS/Ca2+/Mg2+, 1 mg/ml BSA; pH7.4).
Cross-link affinity labeling of cell surface TGF-β receptors using [I]TGF-β1 revealed the presence of two receptors with molecular weights of 53 kDa and 70 kDa on the three cell lines (Fig. 3e, upper panel), whereas a third receptor (molecular weight approximately 250 kDa) could be detected on only the BRI-JM04 and BRI-JM05 cells.
Because the association between MPs and APols is quasi-irreversible in the absence of other surfactants, various functionalities can be added to the MPs by linking affinity, fluorescent, or radioactive tags to the APols without either chemical or genetic modification of the protein.
For treatment of the cells with glycosaminoglycan-cleaving enzymes, subconfluent monolayers were treated with 100 mU heparinitase I, II and III, and 10 mU chondroitinase ABC (Ibex Technologies, Montreal, PQ, USA) in 200 μl binding buffer (3 hours at 37°C) before cross-link affinity-labeling with 100 pmol/l [I]TGF-β1 or [I]TGF-β2.
Both water and chaperones provide a diffuse set of rapidly fluctuating weak links (low affinity and low probability interactions), which allow the generalization of all these statements to a multitude of networks.
