Pentraxin 3 (PTX3) is an acute phase protein strongly expressed by advanced atherosclerotic lesions. We investigated (a) PTX3 expression and secretion in subcutaneous adipose tissue (SAT) and omental visceral adipose tissue (VAT) obtained from 21 obese (37.4 +/- 8.15 yr) and 10 normal weight subjects (43.7 +/- 11.07 yr) and (b) the relationships of adipose PTX3 with tumour necrosis factor alpha (TNF alpha) and adiponectin expression and with cardiometabolic risk factors. Real-time PCR was used to quantify specific mRNA for PTX3, CD68 (macrophage marker), TNF alpha and adiponectin. Fresh adipose tissue was cultured and PTX3 measured in the medium. Serum insulin, glucose, HDL and LDL cholesterol, triglycerides, C-reactive protein (CRP), fibrinogen, adiponectin, TNF alpha and PTX3 were measured. PTX3 expression was similar in the two fat compartments and tended to be higher in obese than in normal weight subjects in VAT only (p=0.05). CD68 and PTX3 expressions were correlated with cacti other in SAT but not in VAT. After adjustment for age and sex, VAT PTX3 expression and release were correlated with VAT-TNF alpha expression (p < 0.01 for both) and with LDL/HDL ratio (p < 0.01 and p < 0.001). VAT PTX3 expression was also correlated with BMI, triglycerides, CRP, fibrinogen and adiponectin (p<0.05 for all). In the multivariate analysis with VAT-PTX3 RNA levels as dependent variable, LDL/HDL ratio and fibrinogen remained independently associated with VAT-PTX3 expression (p<0.01 for both). T here associations were not seen within SAT. Conclusions: Human adipose tissue expresses and releases PTX3 likely under TNF alpha control. VAT production of PTX3 seems to contribute tit the mechanisms underlying the development of atherosclerosis. (C) 2008 Elsevier Ireland Ltd. All rights reserved.