Biomaterial Database

Impaired actin polymerization and depolymerization in neutrophils from patients with thermal injury. 1997

H A Vindenes, and R Bjerknes

Department of Plastic Surgery, University of Bergen, Haukeland Hospital, Norway.

Acquired neutrophil dysfunction is considered an important cause of increased susceptibility to infection in patients with burns. In the early postinjury phase, large amounts of circulating chemo-attractants, cytokines and endotoxins induce strong systemic activation of neutrophils which may impair their motile functions. Actin is the most prevalent component of the microfilament lattice that generates force for the neutrophil motile responses, and in the present study we examined the dynamics of actin polymerization and depolymerization in neutrophils from 11 patients with large burns. At admission, the amount of polymerized actin in unstimulated neutrophils was 39.9 per cent higher than that of parallel controls. In addition, there was a positive correlation between the amount of polymerized actin and the total body surface area (TBSA) burn. The time course of patient neutrophil actin polymerization in response to FMLP, C5a, (Ser-IL-8)72, (Ala-IL-8)77 and crosslinking of surface Fc gamma RII was similar to that of controls, and the maximal amount of neutrophil F-actin was demonstrated after 30 s stimulation. At the peak of actin polymerization, however, patient neutrophils contained 27.3, 24.0, 24.7 and 25.6 per cent more polymerized actin than control cells stimulated with FMLP, (Ser-IL,-8)77, (Ala-8)77 and Fc gamma RII crosslinking, respectively. However, the relative increase of neutrophil F-actin following stimulation was significantly lower in patients than in controls. Moreover, the rate of patient neutrophil actin depolymerization was 39.0, 23.5, 63.3 and 51.7 per cent lower than that of controls after stimulation with FMLP, C5a (Ser-IL-8)72 and Fc gamma RII crosslinking, respectively. At discharge, the dynamics of neutrophil actin polymerization and depolymerization were similar to that of controls. The results demonstrate that in neutrophils during the early postburn phase, there are increased basal levels of polymerized actin, a lower responsiveness to stimulation and a reduced rate of actin depolymerization. As periodic polymerization and depolymerization of actin is essential for all neutrophil motile responses, it is probable that the alterations observed may contribute significantly to the overall neutrophil dysfunction following thermal injury.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009240	N-Formylmethionine Leucyl-Phenylalanine	A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.	F-Met-Leu-Phe,N-Formyl-Methionyl-Leucyl-Phenylalanine,Formylmet-Leu-Phe,Formylmethionyl Peptide,Formylmethionyl-Leucyl-Phenylalanine,Formylmethionylleucylphenylalanine,N-Formylated Peptide,N-formylmethionyl-leucyl-phenylalanine,fMet-Leu-Phe,F Met Leu Phe,Formylmet Leu Phe,Formylmethionyl Leucyl Phenylalanine,Leucyl-Phenylalanine, N-Formylmethionine,N Formyl Methionyl Leucyl Phenylalanine,N Formylated Peptide,N Formylmethionine Leucyl Phenylalanine,N formylmethionyl leucyl phenylalanine,Peptide, Formylmethionyl,Peptide, N-Formylated,fMet Leu Phe
D009504	Neutrophils	Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.	LE Cells,Leukocytes, Polymorphonuclear,Polymorphonuclear Leukocytes,Polymorphonuclear Neutrophils,Neutrophil Band Cells,Band Cell, Neutrophil,Cell, LE,LE Cell,Leukocyte, Polymorphonuclear,Neutrophil,Neutrophil Band Cell,Neutrophil, Polymorphonuclear,Polymorphonuclear Leukocyte,Polymorphonuclear Neutrophil
D002056	Burns	Injuries to tissues caused by contact with heat, steam, chemicals (BURNS, CHEMICAL), electricity (BURNS, ELECTRIC), or the like.	Burn
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D003432	Cross-Linking Reagents	Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.	Bifunctional Reagent,Bifunctional Reagents,Cross Linking Reagent,Crosslinking Reagent,Cross Linking Reagents,Crosslinking Reagents,Linking Reagent, Cross,Linking Reagents, Cross,Reagent, Bifunctional,Reagent, Cross Linking,Reagent, Crosslinking,Reagents, Bifunctional,Reagents, Cross Linking,Reagents, Cross-Linking,Reagents, Crosslinking
D005260	Female		Females
D005434	Flow Cytometry	Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man