Induction of the CXC chemokine interferon-γ-inducible protein 10 regulates the reparative response following myocardial infarction

M Bujak, M Dobaczewski… - Circulation …, 2009 - Am Heart Assoc
M Bujak, M Dobaczewski, C Gonzalez-Quesada, Y Xia, T Leucker, P Zymek, V Veeranna…
Circulation research, 2009Am Heart Assoc
Rationale: Interferon-γ-inducible protein (IP)-10/CXCL10, an angiostatic and antifibrotic
chemokine with an important role in T-cell trafficking, is markedly induced in myocardial
infarcts, and may regulate the reparative response. Objective: To study the role of IP-10 in
cardiac repair and remodeling. Methods and Results: We studied cardiac repair in IP-10-null
and wild-type (WT) mice undergoing reperfused infarction protocols and examined the
effects of IP-10 on cardiac fibroblast function. IP-10-deficient and WT animals had …
Rationale: Interferon-γ-inducible protein (IP)-10/CXCL10, an angiostatic and antifibrotic chemokine with an important role in T-cell trafficking, is markedly induced in myocardial infarcts, and may regulate the reparative response.
Objective: To study the role of IP-10 in cardiac repair and remodeling.
Methods and Results: We studied cardiac repair in IP-10-null and wild-type (WT) mice undergoing reperfused infarction protocols and examined the effects of IP-10 on cardiac fibroblast function. IP-10-deficient and WT animals had comparable acute infarct size. However, the absence of IP-10 resulted in a hypercellular early reparative response and delayed contraction of the scar. Infarcted IP-10−/− hearts exhibited accentuated early dilation, followed by rapid wall thinning during infarct maturation associated with systolic dysfunction. Although IP-10-null and WT mice had comparable cytokine expression, the absence of IP-10 was associated with marked alterations in the cellular content of the infarct. IP-10−/− infarcts had more intense infiltration with CD45+ leukocytes, Mac-2+ macrophages, and α-smooth muscle actin (α-SMA)+ myofibroblasts than WT infarcts but exhibited reduced recruitment of the subpopulations of leukocytes, T lymphocytes and α-SMA+ cells that expressed CXCR3, the IP-10 receptor. IP-10 did not modulate cardiac fibroblast proliferation and apoptosis but significantly inhibited basic fibroblast growth factor-induced fibroblast migration. In addition, IP-10 enhanced growth factor-mediated wound contraction in fibroblast-populated collagen lattices.
Conclusions: Endogenous IP-10 is an essential inhibitory signal that regulates the cellular composition of the healing infarct and promotes wound contraction, attenuating adverse remodeling. IP-10-mediated actions may be due, at least in part, to direct effects on fibroblast migration and function.
Am Heart Assoc