The B3 subfamily of integrins are two-way signaling receptors that play essential roles in cell biology. Their influences on platelet function and vascular biology are particularly prominent. aVB3 receptor serves as a crucial regulation of angiogenesis, the process of blood vessel growth in adult organism which underlies a number of pathologies, including ischemic injury, cancer and tissue repair. Recent studies demonstrated that angiogenesis is a systemic process where vascular cells coordinate actions with immune cells of blood and tissue origin, and circulating blood components. Using a variety of in vivo models we have shown that activation of aVB3 occurs on endothelium at the sites of active angiogenesis and appears to control several angiogenesis-dependent responses including recovery after ischemia, tumor growth and wound healing. Using a knockin mouse model expressing mutant form of B3 unable to undergo phosphorylation, we demonstrated that B3 phosphorylation is essential for neovascularization in vivo. However, abnormal angiogenesis in B3 knockin mice was completely reversed by bone marrow transplantation was and appear to be dictated primarily by B3 integrin on bone marrow derived (BMDC) cells. Many of these recruited cells express CXCR4, a receptor for SDF-1. Moreover, SDF-1 treatment of BMDC seems to modulate cell adhesion via (33 integrin. These studies identified a novel and unconventional function of B3 integrin in angiogenesis and emphasizes that the process of angiogenesis involve co-operation of numerous cell types and tissues. The overall hypothesis to be tested is that aVB3 activation and phosphorylation are essential for in vivo cooperation between blood, bone marrow-derived and endothelial cells. The following Specific Aims are proposed to test our hypothesis:
Aim I. To assess the role of p3 integrin activation and phosphorylation on the interactions between endothelial, bone marrow derived cells and platelets during angiogenesis in vivo. Double transgenic lines, DiYF-GFP and p3-/- GFP mice will be utilized for visualization of BMDC in bone marrow chimeras. We will also determine the role of platelet B3 on angiogenesis and recruitment of BMDC.
Aim II. To assess the molecular and cellular mechanisms controlling interaction between circulating blood cells and endothelium and determine the role of p3 integrin in this process. Endothelial and BMDC cells from WT, B3-/- and B3 knockin mice as well as cells characterized by impaired integrin activation (from Project 1 and 2) will be used.
Aim III. To assess the role of integrin activation in the process of p3 integrindependent adhesion of BMDC to endothelium. We will determine the role of SDF-1/CXCR4 axis in integrinmediated responses. These studies will delineate the cellular and molecular mechanisms of angiogenesis and result in identification of novel therapeutic strategies to treat ischemia, wound and other pathologies.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Program Projects (P01)
Project #
5P01HL073311-09
Application #
8378029
Study Section
Heart, Lung, and Blood Initial Review Group (HLBP)
Project Start
Project End
Budget Start
2012-05-01
Budget End
2013-04-30
Support Year
9
Fiscal Year
2012
Total Cost
$327,283
Indirect Cost
$100,483
Name
Cleveland Clinic Lerner
Department
Type
DUNS #
135781701
City
Cleveland
State
OH
Country
United States
Zip Code
44195
Biswas, Sudipta; Zimman, Alejandro; Gao, Detao et al. (2017) TLR2 Plays a Key Role in Platelet Hyperreactivity and Accelerated Thrombosis Associated With Hyperlipidemia. Circ Res 121:951-962
Hirbawi, Jamila; Bialkowska, Katarzyna; Bledzka, Kamila M et al. (2017) The extreme C-terminal region of kindlin-2 is critical to its regulation of integrin activation. J Biol Chem 292:14258-14269
Ithychanda, Sujay S; Dou, Kevin; Robertson, Stephen P et al. (2017) Structural and thermodynamic basis of a frontometaphyseal dysplasia mutation in filamin A. J Biol Chem 292:8390-8400
Feng, Weiyi; Valiyaveettil, Manojkumar; Dudiki, Tejasvi et al. (2017) ?3 phosphorylation of platelet ?IIb?3 is crucial for stability of arterial thrombus and microparticle formation in vivo. Thromb J 15:22
Zhu, Liang; Yang, Jun; Bromberger, Thomas et al. (2017) Structure of Rap1b bound to talin reveals a pathway for triggering integrin activation. Nat Commun 8:1744
Wang, Yunmei; Gao, Huiyun; Shi, Can et al. (2017) Leukocyte integrin Mac-1 regulates thrombosis via interaction with platelet GPIb?. Nat Commun 8:15559
Ding, Liang; Zhang, Lifang; Biswas, Sudipta et al. (2017) Akt3 inhibits adipogenesis and protects from diet-induced obesity via WNK1/SGK1 signaling JCI Insight 2:
Jawhara, Samir; Pluskota, Elzbieta; Cao, Wei et al. (2017) Distinct Effects of Integrins ?X?2 and ?M?2 on Leukocyte Subpopulations during Inflammation and Antimicrobial Responses. Infect Immun 85:
Sossey-Alaoui, Khalid; Pluskota, Elzbieta; Bialkowska, Katarzyna et al. (2017) Kindlin-2 Regulates the Growth of Breast Cancer Tumors by Activating CSF-1-Mediated Macrophage Infiltration. Cancer Res 77:5129-5141
Ding, Liang; Zhang, Lifang; Kim, Michael et al. (2017) Akt3 kinase suppresses pinocytosis of low-density lipoprotein by macrophages via a novel WNK/SGK1/Cdc42 protein pathway. J Biol Chem 292:9283-9293

Showing the most recent 10 out of 97 publications