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A phage-targeting strategy for the design of spatiotemporal drug delivery from grafted matrices.

Sawada R, Peterson CY, Gonzalez AM, Potenza BM, Mueller B, Coimbra R, Eliceiri BP, Baird A - Fibrogenesis Tissue Repair (2011)

Bottom Line: After three to six rounds of biopanning, phage recovery and phage amplification of the bound particles, any phage that had acquired a capacity to bind the matrix was sequenced.In this first report, we identify distinct classes of matrix-binding peptides which elute differently from the screened matrix and demonstrate that they can be applied in a spatially relevant manner.We suggest that further applications of these combinatorial techniques to wound-healing matrices may offer a new way to improve the performance of clinically approved matrices so as to introduce temporal and spatial control over drug delivery.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego School of Medicine, 200 W, Arbor Dr,, San Diego, CA 92103-8236 USA. anbaird@ucsd.edu.

ABSTRACT

Background: The natural response to injury is dynamic and normally consists of complex temporal and spatial cellular changes in gene expression, which, when acting in synchrony, result in patent tissue repair and, in some instances, regeneration. However, current therapeutic regiments are static and most rely on matrices, gels and engineered skin tissue. Accordingly, there is a need to design next-generation grafting materials to enable biotherapeutic spatiotemporal targeting from clinically approved matrices. To this end, rather then focus on developing completely new grafting materials, we investigated whether phage display could be deployed onto clinically approved synthetic grafts to identify peptide motifs capable of linking pharmaceutical drugs with differential affinities and eventually, control drug delivery from matrices over both space and time.

Methods: To test this hypothesis, we biopanned combinatorial peptide libraries onto different formulations of a wound-healing matrix (Integra®) and eluted the bound peptides with 1) high salt, 2) collagen and glycosaminoglycan or 3) low pH. After three to six rounds of biopanning, phage recovery and phage amplification of the bound particles, any phage that had acquired a capacity to bind the matrix was sequenced.

Results: In this first report, we identify distinct classes of matrix-binding peptides which elute differently from the screened matrix and demonstrate that they can be applied in a spatially relevant manner.

Conclusions: We suggest that further applications of these combinatorial techniques to wound-healing matrices may offer a new way to improve the performance of clinically approved matrices so as to introduce temporal and spatial control over drug delivery.

No MeSH data available.


Related in: MedlinePlus

Summary of phage screening strategy. Libraries of targeted phage were added to either intact matrix (IT1), sonicated immobilized matrix (IT6, IT7 and IT9) or thin sections of matrix (IT8). The blocking strategies with phosphate buffer (P04), bovine serum albumin (BSA) or non fat milk (NFM) were deployed as indicated, and eluates from samples treated with chondroitin sulfate, high salt or high acid, which were processed over three to four rounds (R3, R3/4) of selection before sequence analyses, were used.
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Figure 1: Summary of phage screening strategy. Libraries of targeted phage were added to either intact matrix (IT1), sonicated immobilized matrix (IT6, IT7 and IT9) or thin sections of matrix (IT8). The blocking strategies with phosphate buffer (P04), bovine serum albumin (BSA) or non fat milk (NFM) were deployed as indicated, and eluates from samples treated with chondroitin sulfate, high salt or high acid, which were processed over three to four rounds (R3, R3/4) of selection before sequence analyses, were used.

Mentions: We evaluated and subsequently deployed several strategies to identify peptides capable of interacting with the Integra® matrices. These included the use of 1) two different peptide libraries as starting materials including the PHD-C7C and PHD12 libraries; 2) different formulations of the target including intact, solubilized or cryostat-sectioned matrices for biopanning; 3) different elution buffers including chondroitin sulfate, low pH and high salt; and lastly 4) different blocking buffers including bovine serum albumin (BSA), phosphate-buffered saline containing 0.1% Tween (PBS-T), and non-fat milk (NFM) to limit non-specific binding of phage These variations would allow us to select particles that display different classes of peptides with different affinities for the target matrix. The approaches used are detailed in Table 1 and summarized schematically in Figure 1.


A phage-targeting strategy for the design of spatiotemporal drug delivery from grafted matrices.

Sawada R, Peterson CY, Gonzalez AM, Potenza BM, Mueller B, Coimbra R, Eliceiri BP, Baird A - Fibrogenesis Tissue Repair (2011)

Summary of phage screening strategy. Libraries of targeted phage were added to either intact matrix (IT1), sonicated immobilized matrix (IT6, IT7 and IT9) or thin sections of matrix (IT8). The blocking strategies with phosphate buffer (P04), bovine serum albumin (BSA) or non fat milk (NFM) were deployed as indicated, and eluates from samples treated with chondroitin sulfate, high salt or high acid, which were processed over three to four rounds (R3, R3/4) of selection before sequence analyses, were used.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3050739&req=5

Figure 1: Summary of phage screening strategy. Libraries of targeted phage were added to either intact matrix (IT1), sonicated immobilized matrix (IT6, IT7 and IT9) or thin sections of matrix (IT8). The blocking strategies with phosphate buffer (P04), bovine serum albumin (BSA) or non fat milk (NFM) were deployed as indicated, and eluates from samples treated with chondroitin sulfate, high salt or high acid, which were processed over three to four rounds (R3, R3/4) of selection before sequence analyses, were used.
Mentions: We evaluated and subsequently deployed several strategies to identify peptides capable of interacting with the Integra® matrices. These included the use of 1) two different peptide libraries as starting materials including the PHD-C7C and PHD12 libraries; 2) different formulations of the target including intact, solubilized or cryostat-sectioned matrices for biopanning; 3) different elution buffers including chondroitin sulfate, low pH and high salt; and lastly 4) different blocking buffers including bovine serum albumin (BSA), phosphate-buffered saline containing 0.1% Tween (PBS-T), and non-fat milk (NFM) to limit non-specific binding of phage These variations would allow us to select particles that display different classes of peptides with different affinities for the target matrix. The approaches used are detailed in Table 1 and summarized schematically in Figure 1.

Bottom Line: After three to six rounds of biopanning, phage recovery and phage amplification of the bound particles, any phage that had acquired a capacity to bind the matrix was sequenced.In this first report, we identify distinct classes of matrix-binding peptides which elute differently from the screened matrix and demonstrate that they can be applied in a spatially relevant manner.We suggest that further applications of these combinatorial techniques to wound-healing matrices may offer a new way to improve the performance of clinically approved matrices so as to introduce temporal and spatial control over drug delivery.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Surgery, Division of Trauma, Surgical Critical Care and Burns, University of California San Diego School of Medicine, 200 W, Arbor Dr,, San Diego, CA 92103-8236 USA. anbaird@ucsd.edu.

ABSTRACT

Background: The natural response to injury is dynamic and normally consists of complex temporal and spatial cellular changes in gene expression, which, when acting in synchrony, result in patent tissue repair and, in some instances, regeneration. However, current therapeutic regiments are static and most rely on matrices, gels and engineered skin tissue. Accordingly, there is a need to design next-generation grafting materials to enable biotherapeutic spatiotemporal targeting from clinically approved matrices. To this end, rather then focus on developing completely new grafting materials, we investigated whether phage display could be deployed onto clinically approved synthetic grafts to identify peptide motifs capable of linking pharmaceutical drugs with differential affinities and eventually, control drug delivery from matrices over both space and time.

Methods: To test this hypothesis, we biopanned combinatorial peptide libraries onto different formulations of a wound-healing matrix (Integra®) and eluted the bound peptides with 1) high salt, 2) collagen and glycosaminoglycan or 3) low pH. After three to six rounds of biopanning, phage recovery and phage amplification of the bound particles, any phage that had acquired a capacity to bind the matrix was sequenced.

Results: In this first report, we identify distinct classes of matrix-binding peptides which elute differently from the screened matrix and demonstrate that they can be applied in a spatially relevant manner.

Conclusions: We suggest that further applications of these combinatorial techniques to wound-healing matrices may offer a new way to improve the performance of clinically approved matrices so as to introduce temporal and spatial control over drug delivery.

No MeSH data available.


Related in: MedlinePlus