Article

Morphological and biochemical characterization of macrophages activated by carrageenan and lipopolysaccharide in vivo.

Laboratório de Ultra-estrutura Celular, Departamento de Ultra-estrutura e Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil 4365, Manguinhos, 21045-900, Rio de Janeiro, RJ, Brazil.
Cell Structure and Function (impact factor: 2.29). 05/2004; 29(2):27-34. pp.27-34
Source: PubMed

ABSTRACT Macrophages are able to recognize, internalize and destroy a large number of pathogens, thus restricting the infection until adaptive immunity is initiated. In this work our aim was to analyze the surface charge of cells activated by carrageenan (CAR) and lipopolysaccharide (LPS) through light and electron microscopy approaches as well as the release of inflammatory mediators in vitro. The ultrastuctural analysis and the light microscopy data showed that in vivo administration of CAR represents a potent inflammatory stimulation for macrophages leading to a high degree of spreading, an increase in their size, in the number of the intracellular vacuoles and membrane projections as compared to the macrophages collected from untreated animals as well as mice submitted to LPS. Our data demonstrated that CAR stimulated-macrophages displayed a remarkable increase in nitric oxide production and PGE2 release as compared to the cells collected from non-stimulated and stimulated mice with LPS in vivo. On the other hand, non-stimulated macrophages as well as macrophages stimulated by LPS produce almost the same quantities of TNF-alpha, while in vivo stimulation by CAR leads to a 30-40% increase of cytokine release in vitro compared to the other groups. In conclusion, our morphological and biochemical data clearly showed that in vivo stimulation with CAR induces a potent inflammatory response in macrophages representing an interesting model to analyze inflammatory responses.

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Keywords

adaptive immunity
 
CAR induces
 
CAR stimulated-macrophages
 
carrageenan
 
cytokine release
 
inflammatory mediators
 
inflammatory responses
 
interesting model
 
intracellular vacuoles
 
light microscopy data
 
membrane projections
 
nitric oxide production
 
non-stimulated macrophages
 
PGE2 release
 
potent inflammatory response
 
potent inflammatory stimulation
 
remarkable increase
 
untreated animals
 
vivo administration
 
vivo stimulation