Formylpeptides trigger selective molecular pathways that are required in the physiological functions of human neutrophils.

Rita Selvatici; Sofia Falzarano; Serena Traniello; Giampiero Pagani Zecchini; Susanna Spisani

doi:10.1016/s0898-6568(02)00123-7

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Formylpeptides trigger selective molecular pathways that are required in the physiological functions of human neutrophils.

Rita Selvatici·Sofia Falzarano·Serena Traniello·Giampiero Pagani Zecchini·Susanna Spisani

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Abstract

For-Met-Delta(z)Leu-Phe-OMe ([Delta(z)Leu(2)]) is a conformationally restricted for-Met-Leu-Phe-OMe (fMLP-OMe) analogue able to discriminate between different responses of human neutrophils. In contrast, [Delta(z)Leu(2)] significantly activates the transduction pathways-involving Ca(2+), inositol phosphate, and cyclic AMP (cAMP) enhancement, as is the case with the full agonist fMLP-OMe. Here, we have studied the specific involvement of protein kinase C (PKC) isoforms and mitogen activated protein kinases (MAPKs) in the presence or absence of extracellular Ca(2+), being the cation clearly involved in the activation of neutrophils by fMLP. A strong correlation has been found between PKC isoforms, MAPKs and the selective physiological functions by [Delta(z)Leu(2)]-activated neutrophils. In a calcium-free condition, our data suggest that the failure of PKC beta1 translocation and of p38 MAPK phosphorylation by the analogue refers to its inability to induce chemotaxis, and that the failure by both fMLP-OMe and [Delta(z)Leu(2)] to evoke extracellular response kinase 1 and 2 (ERK1/2) phosphorylation would suggest a reduction in superoxide anion production.

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Calcium Calcium Signaling Cells, Cultured Chemotaxis, Leukocyte Enzyme Activation Humans In Vitro Techniques Mitogen-Activated Protein Kinase Kinases N-Formylmethionine Leucyl-Phenylalanine Neutrophils Phosphorylation Protein Kinase C Superoxides Journal Article Research Support, Non-U.S. Gov't

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Rita Selvatici, Sofia Falzarano, Serena Traniello, Giampiero Pagani Zecchini, Susanna Spisani. 2003. Formylpeptides trigger selective molecular pathways that are required in the physiological functions of human neutrophils.. https://doi.org/10.1016/s0898-6568(02)00123-7

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