Neutrophils (PMN) are primary phagocytic cells in the blood and tissue spaces. These terminally differentiated cells have a 1-2 day half-life and are considered capable of little if any protein synthesis and their functional ability has been presumed to last only as long as pools of preformed molecules lasted. However, it has been shown by the applicant that circulating PMN are capable of synthesizing mRNA transcripts and protein and that the levels of protein synthesis are increased when cells are treated with the cytokine GM-CSF. Since PMN are important phagocytic cells, the contribution of de novo protein synthesis to function and lifespan of these cells is of great interest. In this proposal, the complement receptor type 1 (CR1), which is important in the phagocytic function of PMN will be used as a model protein. The objectives of this proposal will study: I. constitutive levels and modulation of mRNA and protein synthesis in peripheral blood PMN using Northern blot and mRNA synthesis assays and pulse-chase experients analyzed by immunoprecipitation, electrophoresis and autoradiography, II. the site of the rapidly upregulatable intracellular pool of CR1 by imunocytochemical, biochemical and immunological techniques and, III. phagocytic pathways of CR1 induced by ligand-dependent or independent stimuli from the time of CR1 plasma membrane expression to intern- alization and subsequent fate. These studies are technically feasible because of the development by the applicant of systems to analyze synthesis of MRNA transcripts and proteins by peripheral blood PMN, development of antibodies to CR1 which are necessary for measurement of cell surface expression of these proteins by flow cytometry, and for quantitation of these molecules by radioimmunoassays capable of detecting 5 x 10-14 moles of CR1 and the development of immunocytochemical electron micrographic methodology for localizing CR1.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI026292-02
Application #
3140049
Study Section
Allergy and Immunology Study Section (ALY)
Project Start
1989-09-30
Project End
1994-07-31
Budget Start
1990-08-01
Budget End
1991-07-31
Support Year
2
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Brigham and Women's Hospital
Department
Type
DUNS #
071723621
City
Boston
State
MA
Country
United States
Zip Code
02115
Feinberg, Bruce B; Jack, Richard M; Mok, Samuel C et al. (2005) Low erythrocyte complement receptor type 1 (CR1, CD35) expression in preeclamptic gestations. Am J Reprod Immunol 54:352-7
Wang, C; Barbashov, S; Jack, R M et al. (1995) Hemolytically inactive C5b67 complex: an agonist of polymorphonuclear leukocytes. Blood 85:2570-8
Jack, R M; Lowenstein, B A; Nicholson-Weller, A (1994) Regulation of C1q receptor expression on human polymorphonuclear leukocytes. J Immunol 153:262-9
Anderson, D J; Abbott, A F; Jack, R M (1993) The role of complement component C3b and its receptors in sperm-oocyte interaction. Proc Natl Acad Sci U S A 90:10051-5
Rogers, R A; Jack, R M; Furlong, S T (1993) Lipid and membrane protein transfer from human neutrophils to schistosomes is mediated by ligand binding. J Cell Sci 106 ( Pt 2):485-91
Neuman, E; Huleatt, J W; Vargas, H et al. (1992) Regulation of MHC class I synthesis and expression by human neutrophils. J Immunol 148:3520-7
Moore Jr, F D; Jack, R M; Antin, J H (1992) Peripheral blood neutrophils in chronically neutropenic patients respond to granulocyte-macrophage colony-stimulating factor with a specific increase in CR1 expression and CR1 transcription. Blood 79:1667-71
Penrose, J F; Gagnon, L; Goppelt-Struebe, M et al. (1992) Purification of human leukotriene C4 synthase. Proc Natl Acad Sci U S A 89:11603-6
Neuman, E; Huleatt, J W; Jack, R M (1990) Granulocyte-macrophage colony-stimulating factor increases synthesis and expression of CR1 and CR3 by human peripheral blood neutrophils. J Immunol 145:3325-32