Leukocytes such as polymorphonuclear leukocytes (PMN) and macrophages, play an important role both in immune complex disease and in host defense. Macrophages and PMN express on their surface Fcgamma receptors (FcgammaR) which 1) interact with IgG containing immune complexes to produce tissue damage, but 2) also function to clear IgG coated bacteria in host defense. In the lung, Fc receptors and, importantly, the individual Fc receptors have been little studied. We will employ transgenic mice and mice deficient in specific FcR in a combined in vitro and in vivo molecular and cell biology approach to elucidate the role of individual Fc receptors in an animal model of immune lung injury. Both human and mouse macrophages express the activating FcgammaRs FcgammaRI and FcgammaRIIIA which interact with a FcR gamma subunit. We have determined that FcgammaRI is unique among FcR not only in the ability to bind monomeric IgG, but also to signal through both its alpha and gamma subunits. Human macrophages and PMN also express the potent activating FcR FcgammaRIIA, which is absent in mice and does not interact with the y chain. We now have available FcgammaRIIA transgenic (TG) mice, which we have determined express FcgammaRIIA on the macrophage surface to a similar extent as humans and have enhanced clearance of IgG coated cells. Our novel mouse strains include: 1) mice individually lacking either FcgammaRI, FcgammaRIIIA or the gamma chain and 2) mice TG for human FcgammaRIIA (as well as FcgammaRIIA crosses) developed with the participation of our laboratory. Our hypothesis, suggested by our data, is that in the lung FcgammaRI plays a predominant role in the release of inflammatory mediators, while FcgammaRIIA plays a predominant role in host defense. Elucidating the role(s) of specific leukocyte FcgammaRs in the lung is potentially important for developing strategies for effective therapy. Another goal is to define the molecular mechanisms involved in specific mediator release induced by individual lung macrophage FcR, specifically FcgammaRI. We have determined that the cytoplasmic domain (CY) of the FcgammaRI alpha chain is required for release of macrophage IL-6. We will examine structure/function relationships of FcgammaRI involved in signaling for IL-6 release. Human FcgammaRI and chimeras of human FcgammaRI, containing transmembrane domains which cannot associate with endogenous murine Fcgamma receptors, will be transfected into a murine macrophage cell line. Our hypothesis is that specific sequences in the FcgammaRI alpha chain CY, but not the gamma chain, are required for IL-6 release.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL069498-03
Application #
6616072
Study Section
Special Emphasis Panel (ZHL1-CSR-P (S1))
Program Officer
Colombini-Hatch, Sandra
Project Start
2001-09-30
Project End
2005-07-31
Budget Start
2003-08-01
Budget End
2004-07-31
Support Year
3
Fiscal Year
2003
Total Cost
$355,300
Indirect Cost
Name
University of Pennsylvania
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Ulanova, Marina; Asfaha, Samuel; Stenton, Grant et al. (2007) Involvement of Syk protein tyrosine kinase in LPS-induced responses in macrophages. J Endotoxin Res 13:117-25
Ulanova, Marina; Schreiber, Alan D; Befus, A Dean (2006) The future of antisense oligonucleotides in the treatment of respiratory diseases. BioDrugs 20:1-11
Duta, Florentina; Ulanova, Marina; Seidel, Daniel et al. (2006) Differential expression of spleen tyrosine kinase Syk isoforms in tissues: Effects of the microbial flora. Histochem Cell Biol 126:495-505
Ulanova, Marina; Marcet-Palacios, Marcelo; Munoz, Samira et al. (2006) Involvement of Syk kinase in TNF-induced nitric oxide production by airway epithelial cells. Biochem Biophys Res Commun 351:431-7
Ulanova, Marina; Puttagunta, Lakshmi; Marcet-Palacios, Marcelo et al. (2005) Syk tyrosine kinase participates in beta1-integrin signaling and inflammatory responses in airway epithelial cells. Am J Physiol Lung Cell Mol Physiol 288:L497-507
Huang, Zhen-Yu; Hunter, Sharon; Kim, Moo-Kyung et al. (2004) The monocyte Fcgamma receptors FcgammaRI/gamma and FcgammaRIIA differ in their interaction with Syk and with Src-related tyrosine kinases. J Leukoc Biol 76:491-9
Albelda, Steven M; Lau, Kelvin C; Chien, Paul et al. (2004) Role for platelet-endothelial cell adhesion molecule-1 in macrophage Fcgamma receptor function. Am J Respir Cell Mol Biol 31:246-55
Huang, Zhen-Yu; Hunter, Sharon; Kim, Moo-Kyung et al. (2003) The effect of phosphatases SHP-1 and SHIP-1 on signaling by the ITIM- and ITAM-containing Fcgamma receptors FcgammaRIIB and FcgammaRIIA. J Leukoc Biol 73:823-9
Santini, Valeria; Scappini, Barbara; Indik, Zena K et al. (2003) The carboxy-terminal region of the granulocyte colony-stimulating factor receptor transduces a phagocytic signal. Blood 101:4615-22
Kim, Moo-Kyung; Huang, Zhen-Yu; Hwang, Pyoung-Han et al. (2003) Fcgamma receptor transmembrane domains: role in cell surface expression, gamma chain interaction, and phagocytosis. Blood 101:4479-84