TITLE:
Comparison of YKL-39 and CHIT-1 expression during macrophages differentiation and polarization
AUTHORS:
Michelino Di Rosa, Daniele Tibullo, Michele Malaguarnera, Michele Tuttobene, Lucia Malaguarnera
KEYWORDS:
YKL-39; Chitotriosidase; Human Monocyte/Macrophages; Classically Activated Macrophages; Alternatively Activated Macrophages
JOURNAL NAME:
Modern Research in Inflammation,
Vol.2 No.4,
November
26,
2013
ABSTRACT: The chitinase-like
proteins YKL-39 (chitinase 3-like-2) and Chitortriosidase (CHIT-1) are members
of the chitinases family. YKL-39 expression has
been associated with osteoarthritis, whereas CHIT-1 activity is regarded
as a biochemical marker of macrophage activation. So far, the physiological or
pathological role of YKL-39 in the inflammation is still poorly understood. We
compared YKL-39 and CHIT-1 modulation during monocyte to macrophage transition
and polarization. Gene expression analysis was investigated by real-time PCR
from mRNA of human monocytes obtained from buffy coat of healthy volunteers, from mRNA of polarized macrophages
to classically activated macrophages (or M1),
obtained by interferon-γ and
lipopolysaccharide exposure, and from mRNA of alternatively activated
macrophages (or M2) obtained by interleukin-4 exposure. We
demonstrated different variations of YKL-39 and CHIT-1 production during macrophages
polarization. CHIT-1 levels gradually increase in the course of the time with a
peak of expression between the fifth and the seventh day of culture. In contrast, YKL-39 expression was
unaltered in the diverse stage of HMMs differentiation, but increased significantly
in M1 polarized macrophages and
reverted to base levels in M2 polarized macrophages. These
findings indicated that the function of
YKL-39 is much more restricted and selective than that exerted by CHIT-1.