Reduced immunoregulatory CD31+ T cells in the blood of atherosclerotic mice with plaque thrombosis.
OBJECTIVE
Lymphocyte activation is thought to play a major role in the pathogenesis of atherosclerotic complications such as plaque thrombosis. Circulating CD31+ T cells have been shown to regulate human T cell activation. Aim of this study was to evaluate whether the proportion of circulating immunoregulatory CD31+ T cells is correlated to the occurrence of plaque thrombosis in aged apolipoprotein (apo) E knockout (KO) mice.


RESULTS
CD31+ T cell depletion of spleen T cells enhanced proliferation (P<0.05) and interferon-gamma production (P<0.01) while reducing interleukin (IL)-4 (P<0.001) and IL-10 (P=0.001) secretion in response to minimally modified low-density lipoprotein. CD31+ T cells were counted in 65 apoE KO mice (46-week-old) by flow cytometry. Organizing thrombi could be documented in 28 of 195 (14%) lesions and in at least one of the aorta root lesions in 23 of 65 mice (35%). CD31+ T cell count was significantly reduced in mice showing plaque thrombosis (72.3+/-1.5% versus 84.1+/-1.2%; P<0.0001), but such reduction did not follow induced plaque rupture or experimentally controlled thrombosis.


CONCLUSIONS
Reduced CD31+ T cells in circulating blood is a hallmark of atherosclerotic plaque thrombosis. Our data suggest that CD31+ T cells may play an important regulatory role in the development of plaque thrombosis.
Caligiuri
Giuseppina
G
EMI0016, Institut des Cordeliers, INSERM, Paris, France. caligiuri@necker.fr
Groyer
Emilie
E
Khallou-Laschet
Jamila
J
Al Haj Zen
Ayman
A
Sainz
Julie
J
Urbain
Dominique
D
Gaston
Anh-Thu
AT
Lemitre
Mathilde
M
Nicoletti
Antonino
A
Lafont
Antoine
A
D000818:Animals; D001057:Apolipoproteins E / Q000235:genetics; D050197:Atherosclerosis / Q000276:immunology* / Q000473:pathology; D015415:Biomarkers; D005260:Female; D007150:Immunohistochemistry; D008213:Lymphocyte Activation / Q000276:immunology*; D018655:Lymphocyte Count; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012421:Rupture; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D013927:Thrombosis / Q000276:immunology* / Q000473:pathology
D001057:Apolipoproteins E; D015415:Biomarkers; D019408:Platelet Endothelial Cell Adhesion Molecule-1