Deficiency of the long pentraxin PTX3 promotes vascular inflammation and atherosclerosis.
BACKGROUND
Immune responses participate in several phases of atherosclerosis; there is, in fact, increasing evidence that both adaptive immunity and innate immunity tightly regulate atherogenesis. Pentraxins are a superfamily of acute-phase proteins that includes short pentraxins such as C-reactive protein or long pentraxins such as PTX3, a molecule acting as the humoral arm of innate immunity. To address the potential role of PTX3 in atherogenesis, we first investigated the expression of PTX3 during atherogenesis, generated double-knockout mice lacking PTX3 and apolipoprotein E, and then studied the effect of murine PTX3 deficiency on plasma lipids, atherosclerosis development, and gene expression pattern in the vascular wall.


RESULTS
PTX3 expression increases in the vascular wall of apolipoprotein E-knockout mice from 3 up to 18 months of age. Double-knockout mice lacking PTX3 and apolipoprotein E were fed an atherogenic diet for 16 weeks. Aortic lesions were significantly increased in double-knockout mice and mice heterozygous for PTX3 compared with apolipoprotein E-knockout mice. Mice lacking PTX3 showed a more pronounced inflammatory profile in the vascular wall as detected by cDNA microarray and quantitative polymerase chain reaction analysis and an increased macrophage accumulation within the plaque. Finally, lesion size correlated with the number of bone marrow monocytes.


CONCLUSIONS
PTX3 has atheroprotective effects in mice, which, in light of the cardioprotective effects recently reported, suggests a cardiovascular protective function of the long pentraxin 3 through the modulation of the immunoinflammatory balance in the cardiovascular system.
Norata
Giuseppe Danilo
GD
Department of Pharmacological Sciences, Università degli Studi di Milano, Milan, Italy. Danilo.Norata@unimi.it
Marchesi
Patrizia
P
Pulakazhi Venu
Vivek Krishna
VK
Pasqualini
Fabio
F
Anselmo
Achille
A
Moalli
Federica
F
Pizzitola
Irene
I
Garlanda
Cecilia
C
Mantovani
Alberto
A
Catapano
Alberico Luigi
AL
D000818:Animals; D001011:Aorta / Q000473:pathology / Q000502:physiology; D001057:Apolipoproteins E / Q000235:genetics; D050197:Atherosclerosis / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D001835:Body Weight; D002097:C-Reactive Protein / Q000235:genetics* / Q000276:immunology*; D005260:Female; D015870:Gene Expression / Q000276:immunology; D008055:Lipids / Q000097:blood; D008264:Macrophages / Q000473:pathology; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000276:immunology*; D012737:Sex Factors; D014657:Vasculitis / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D000099153:Pentraxins
D001057:Apolipoproteins E; D002097:C-Reactive Protein; D008055:Lipids; D009419:Nerve Tissue Proteins; D000099153:Pentraxins