Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3-4
pubmed:dateCreated
2005-4-5
pubmed:abstractText
Neutrophils are the first line of immunity against most pathogens that infect cattle. These normally short-lived white blood cells develop from myeloid-lineage cells in bone marrow. Upon maturation, bone marrow neutrophils are released into the circulation where they marginate on inflamed blood vessel endothelial cells and migrate through them into the area of infection. Once migrated, neutrophils do not reenter the circulation, but rather, perform their bactericidal functions and die by apoptosis in the tissue. The cytokine and hormonal milieu of the blood and extracellular tissue fluid can influence neutrophil development and immunity-related activities, but the molecular basis of these phenotypic changes and physiological benefits or drawbacks of them are poorly understood. In the current paper, we review new gene expression information that resulted from two of our functional genomics studies designed to evaluate effects of glucocorticoid hormones on bovine neutrophils. This work provides one model to describe complex changes that occur in neutrophils as the cells respond to glucocorticoids, which might act to alter the cells' functional priorities and tip the delicate balance between health and disease during stress, including at parturition. A bovine immunobiology microarray and real time RT-PCR were used to study blood neutrophils collected during the natural surge of endogenous glucocorticoid (cortisol) in parturient dairy cows and bone marrow neutrophils collected from glucocorticoid (dexamethasone)-treated dairy steers. The gene expression signatures we observed led us to perform additional phenotyping of the neutrophils and correlation analyses, which together painted a picture suggesting that glucocorticoids have key roles in modulating neutrophil development, life span, and tissue defense functions during parturition and hormone therapy. Based on these observations, we postulate that glucocorticoids orchestrate adaptive changes in the entire neutrophil system that support increased cell numbers and longevity in blood and heightened remodeling activity in tissues, while at the same time decreasing some important antimicrobial defense activities of the cells. Thus, our functional genomics studies have enabled us to elucidate multiple consequences of neutrophil exposure to glucocorticoids, highlighting a probable role for this interaction in the induction of parturition and partly explaining why some parturient dairy cows may experience heightened incidence and severity of inflammatory diseases like mastitis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0165-2427
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
105
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
197-219
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Gene expression signatures in neutrophils exposed to glucocorticoids: a new paradigm to help explain "neutrophil dysfunction" in parturient dairy cows.
pubmed:affiliation
Immunogenetics Laboratory, Department of Animal Science, Michigan State University, 1205E Anthony Hall, East Lansing, MI 48824, USA. burtonj@msu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't