Differences between unstimulated and stimulated human male and female
neutrophils in protein and phosphoprotein profiles
Abstract
Human males and females show differences in the incidence of
neutrophil-associated diseases and differences in neutrophil responses
such as a faster response to the chemorepellent SLIGKV in males. Little
is known about the basis of sex-based differences in human neutrophils.
We used mass spectrometry to identify proteins and phosphoproteins in
unstimulated human neutrophils and in neutrophils incubated with the
SLIGKV, a protease activated receptor 2 agonist. There were 132 proteins
with higher levels in unstimulated male neutrophils; these proteins
tended to be associated with RNA regulation, ribosome, and
phosphoinositide signaling pathways, whereas 30 proteins with higher
levels in unstimulated female neutrophils were associated with metabolic
processes, proteosomes, and phosphatase regulatory proteins.
Unstimulated male neutrophils had increased phosphorylation of 32
proteins compared to females. After exposure to SLIGKV, male neutrophils
showed a faster response in terms of protein phosphorylation compared to
female neutrophils. Male neutrophils have higher levels of proteins and
higher phosphorylation of proteins associated with RNA processing and
signaling pathways. Female neutrophils have higher levels of proteins
associated with metabolism and proteolytic pathways. This suggests that
male neutrophils might be more ready to adapt to a new environment, and
female neutrophils might be more effective at responding to pathogens.