Experimental myocardial infarction in rats led to a marked increase in interstitial dendritic cells in the infarct border zone, peaking at 796 cells/mm2 at 7 days compared to 82 in controls.
In a rat model of myocardial infarction, interstitial dendritic cells migrate to the infarct border zone and associate with T-helper lymphocytes, suggesting a role in post-infarction immune responses.
Absolute Event Rate: 796% vs 82%
BACKGROUND: This study was undertaken to investigate the qualitative and quantitative changes that interstitial dendritic cells (IDC) of the heart undergo during the time course of experimental myocardial infarction. METHODS AND RESULTS: Left coronary arterial ligations were performed in 43 rats that were killed 2, 4, 7, 14, and 21 days after surgery. Thirteen unoperated and 39 sham-operated rats were used as controls. Frozen sections were stained with monoclonal antibodies (OX 6 and W3/25) to identify and count IDC by light microscopy. Immunoelectron microscopy was also used to identify IDC. The number of IDC per mm2 of tissue section was calculated for all hearts. In hearts with myocardial infarction, IDC were counted in three areas: the center of the myocardial infarction, the border zone, and the noninfarcted left ventricle. In OX 6 antibody-stained preparations, the number of IDC per mm2 was 82 +/- 10 in the left ventricle of unoperated rats. Hearts with myocardial infarction showed marked increases in the numbers of IDC per mm2 in the border zone (796 +/- 79 at 7 days and 528 +/- 98 at 14 days). In the border zone, IDC often were associated with small clusters of T-helper lymphocytes, which reacted with W3/25 antibody (the rat homologue of human CD4). The center of the myocardial infarction showed an increase in IDC only on day 7 (120 +/- 18). By 21 days, IDC in the border zone were only slightly increased (159 +/- 15). CONCLUSIONS: These findings suggest that IDC migrate to the myocardial infarction border zone. They participate in the activation of lymphocytes and in the initiation of immune responses and decrease in number as inflammation subsides and scarring develops.
Zhang et al. (Mon,) conducted a other in Experimental myocardial infarction (n=95). Experimental myocardial infarction (left coronary arterial ligation) vs. Sham-operated and unoperated rats was evaluated on Number of interstitial dendritic cells (IDC) per mm2. Experimental myocardial infarction in rats led to a marked increase in interstitial dendritic cells in the infarct border zone, peaking at 796 cells/mm2 at 7 days compared to 82 in controls.