Foreign particles in serum activate human neutrophils by binding to specific receptors on the cell surface. Ligand binding causes a signal to be transduced through the membrane which activates many intracellular processes. Some of the processes in the mechanism for particle destruction include protein phosphorylation, phagocytosis of the particle, and the production and secretion of toxic oxygen species (i.e. superoxide anion and hydrogen peroxide) and intracellular granule contents. In pathological cases of altered neutrophil function, such as in chronic granulomatous disease or specific granule deficiency, severe infections and potentially lethal situations may quickly arise from the neutrophil's inability to accomplish all phases of the destructive process. The long term goal of this project is to detail the mechanism for activating immune functions through protein phosphorylation. Protein kinase C (PKC), which is calcium and phospholipid-dependent, has been implicated as a regulator of several neutrophil immune functions. Specifically, this project will lead to: (1) a detailed model for protein kinase C (PKC) translocation and its binding to membranes; (2) the characterization of substrates for PKC which, when phosphorylated, may potentiate the stimulatory signal; (3) further characterization of an endogenous protein kinase C inhibitor (PKC-I) with special regard for its role as a modulator of PKC. In general, knowledge of these mechanisms, obtained through unique complimentary biochemical and morphological approaches, will further our understanding of neutrophil immune functions through protein phosphorylation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
1R29AI025641-01
Application #
3454540
Study Section
Hematology Subcommittee 2 (HEM)
Project Start
1988-02-01
Project End
1993-01-31
Budget Start
1988-02-01
Budget End
1989-01-31
Support Year
1
Fiscal Year
1988
Total Cost
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Type
Schools of Medicine
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Balazovich, K J; McEwen, E L; Lutzke, M L et al. (1992) Purification of PKC-I, an endogenous protein kinase C inhibitor, and types II and III protein kinase C isoenzymes from human neutrophils. Biochem J 284 ( Pt 2):399-405
Balazovich, K J; Almeida, H I; Boxer, L A (1991) Recombinant human G-CSF and GM-CSF prime human neutrophils for superoxide production through different signal transduction mechanisms. J Lab Clin Med 118:576-84
Peters-Golden, M; McNish, R W; Sporn, P H et al. (1991) Basal activation of protein kinase C in rat alveolar macrophages: implications for arachidonate metabolism. Am J Physiol 261:L462-71
Weston, B; Axtell, R A; Todd 3rd, R F et al. (1991) Clinical and biologic effects of granulocyte colony stimulating factor in the treatment of myelokathexis. J Pediatr 118:229-34
Bitar, K N; Hillemeier, C; Biancani, P et al. (1991) Regulation of smooth muscle contraction in rabbit internal anal sphincter by protein kinase C and Ins(1,4,5)P3. Am J Physiol 260:G537-42
Balazovich, K J; Boxer, L A (1990) Extracellular adenosine nucleotides stimulate protein kinase C activity and human neutrophil activation. J Immunol 144:631-7
Francis, J W; Smolen, J E; Balazovich, K J et al. (1990) Calcium-dependent fusion of the plasma membrane fraction from human neutrophils with liposomes. Biochim Biophys Acta 1025:1-9
Balazovich, K J; Boxer, L A (1988) Human neutrophil protein kinase C: calcium-induced changes in the solubility of the enzyme do not always correlate with enzymatic activity. Biochim Biophys Acta 970:305-17