Research

Proteomic analysis of total cellular proteins of human neutrophils

Gisele G Tomazella^1,2 , Idalete da Silva¹ , Helen J Laure¹ , José C Rosa¹ , Roger Chammas³ , Harald G Wiker⁴ , Gustavo A de Souza⁴ and Lewis J Greene^1,2

¹  Centro de Química de Proteínas, Centro Regional de Hemoterapia e Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Ribeirão Preto, Brasil

²  Departmento de Bioquímica, Disciplina de Biologia Molecular, Universidade Federal de São Paulo, São Paulo, Brasil

³  Laboratório de Oncologia Experimental LIM/24, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil

⁴  Section for Microbiology and Immunology, The Gade Institute, University of Bergen, Bergen, Norway

author email corresponding author email

Proteome Science 2009, 7:32doi:10.1186/1477-5956-7-32

Published:	31 August 2009

Abstract

Background

Neutrophils are the most abundant leukocytes in peripheral blood and represent one of the most important elements of innate immunity. Recent subcellular proteomic studies have focused on the identification of human neutrophil proteins in various subcellular membrane and granular fractions. Although there are relatively few studies dealing with the analysis of the total extract of human neutrophils, many biological problems such as the role of chemokines, adhesion molecules, and other activating inputs involved in neutrophil responses and signaling can be approached on the basis of the identification of the total cellular proteins.

Results

Using gel-LC-MS/MS, 251 total cellular proteins were identified from resting human neutrophils. This is more than ten times the number of proteins identified by an initial proteome analysis of human neutrophils and almost five times the number of proteins identified by the first 2-DE map of extracts of rat polymorphonuclear leukocytes. Most of the proteins identified in the present study are well-known, but some of them, such as neutrophil-secreted proteins and centaurin beta-1, a cytoplasmic protein involved in the regulation of NF-κB activity, are described here for the first-time.

Conclusion

The present report provides new information about the protein content of human neutrophils. Importantly, our study resulted in the discovery of a series of proteins not previously reported to be associated with human neutrophils. These data are relevant to the investigation of comparative pathological states and models for novel classes of pharmaceutical drugs that could be useful in the treatment of inflammatory disorders in which neutrophils participate.