Activation of monocyte-derived cells occurs at most sites of inflammation and serves as a first line of defense in the immune system by removing foreign objects and by signaling to other immune cells. Activated macrophages are now known to be heterogeneous populations of cells that can mediate both pro-inflammatory (classically-activated macrophage, or M1 cells) or pro-healing (alternatively-activated macrophage, or M2 cells) behavior. It has been shown that cytokines expressed by M2 cells help to regulate M1 behavior by moderating the inflammatory response. Thus, the balance between M1 and M2 cells is hypothesized to be important in the normal healing response. Recently, heightened activity from M1 or M2 cells has been associated with several disease states, including fibrosis, atherosclerosis, and tumor progression. Interestingly, recent studies indicate plasticity even in differentiated macrophage cells, including evidence of repolarization of activated macrophage. Bioengineering technologies that identify harness and direct specific subpopulations of monocyte-derived cells are therefore critical tools in the development of cell-based therapy approaches addressing the aforementioned diseases. The overall goal of this proposal is to develop M1- and M2-specific peptides that can be used as cell markers or as targeting ligands to deliver modulating drugs to sub-populations of activated macrophages. This goal will be achieved by first identifying M1- and M2-binding peptides from combinatorial libraries by sequential negative and positive biopanning. Potential M1- and M2-peptides will be synthesized and tested by flow cytometry and confocal microscopy. Binding peptides will then be conjugated to quantum dots to serve as cell specific markers and assessed in mixed cell populations and in tissue sections. In addition, peptides will be conjugated to nanoparticles and evaluated for targeted delivery to sub-populations of activated macrophages. Finally, the cross-species recognition of M1 and M2 cells by these peptides will be assessed in non-human primate and human tissue sections. Public Health Relevance: An imbalance in subpopulations (M1 and M2) of activated macrophage cells resulting in heightened or prolonged activity from either M1 or M2 cells has been hypothesized to contribute toward diseases such as fibrosis and atherosclerosis. The goal of this work is to develop M1- and M2-specific peptides that can be used to identify, purify, or target these macrophage subpopulations. Bioengineering technologies that identify, harness and direct specific subpopulations of monocyte-derived cells are critical tools in the development of cell-based therapy approaches addressing the aforementioned diseases.

Public Health Relevance

An imbalance in subpopulations (M1 and M2) of activated macrophage cells resulting in heightened or prolonged activity from either M1 or M2 cells has been hypothesized to contribute toward diseases such as fibrosis and atherosclerosis. The goal of this work is to develop M1- and M2-specific peptides that can be used to identify, purify, or target these macrophage subpopulations. Bioengineering technologies that identify, harness and direct specific subpopulations of monocyte-derived cells are critical tools in the development of cell-based therapy approaches addressing the aforementioned diseases.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21HL093385-01A1
Application #
7638670
Study Section
Innate Immunity and Inflammation Study Section (III)
Program Officer
Buxton, Denis B
Project Start
2009-08-05
Project End
2011-07-31
Budget Start
2009-08-05
Budget End
2010-07-31
Support Year
1
Fiscal Year
2009
Total Cost
$195,000
Indirect Cost
Name
University of Washington
Department
Biomedical Engineering
Type
Schools of Engineering
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Rohani, Maryam G; McMahan, Ryan S; Razumova, Maria V et al. (2015) MMP-10 Regulates Collagenolytic Activity of Alternatively Activated Resident Macrophages. J Invest Dermatol 135:2377-2384
Cieslewicz, Maryelise; Tang, Jingjing; Yu, Jonathan L et al. (2013) Targeted delivery of proapoptotic peptides to tumor-associated macrophages improves survival. Proc Natl Acad Sci U S A 110:15919-24