Figure 5. Depletion of the post-MI increase in M2-like macrophages in Trib1–/– mice resulted in a critically deteriorated prognosis.
(A) The post-MI survival of mice was dramatically reduced in the KO group (Trib1–/– mice; n = 12) compared with that of the WT group (WT littermates; n = 26), but this effect was fully reversed by transplanting BMDMs in Matrigel (KO plus BMDMs group, n = 10). The control transplantation (KO plus Matrigel group; injection of Matrigel only, n = 10) did not affect the survival rates of the KO group. *P < 0.05 versus both KO and KO plus Matrigel groups, log-rank test. (B) The cardiac rupture rate over a 28-day post-MI period was increased by 9-fold in the KO group compared with the rupture rate in the WT group. This fatal event was prevented in the KO plus BMDMs group. The control transplantation (KO plus Matrigel group) did not influence the cardiac rupture rate in the KO group. n = the same as in A in each group. P < 0.05 versus both the KO and KO plus Matrigel groups, χ2 test. (C) Echocardiographic analysis revealed exacerbated cardiac dysfunction in the KO group, while this deterioration was ameliorated in the KO plus BMDMs group. n (day 0, day, 7, and day 28) = 12, 10, and 10 in the WT group; 12, 5, and 1 in the KO group; and 10, 6, and 6 in the KO plus BMDMs group. *P < 0.05 versus the corresponding time point for the KO group, repeated-measures ANOVA. (Note that the day-28 data were not included in the calculation, because n = 1 in the KO group; Trib1–/– mice rarely survived for 28 days after MI.) LVDd, LV end-diastolic dimension; LVDs, LV end-systolic dimension; LVEF, LV ejection fraction; MG, Matrigel. See Supplemental Table 1 for more detailed echocardiographic data.