Antigens and granularity of blood monocytes in relation to inflammatory markers and lipids in postmenopausal women.

OBJECTIVES

The menopause is associated with an increase of inflammatory markers (C-reactive protein, fibrinogen), cytokines (INFgamma, TNF, etc.) and blood lipoproteins. In vitro, CRP, LDL and fibrinogen can modulate or potentiate interleukines production by monocytes. The aim of this work was to study, the relationships in vivo between hs-CRP, fibrinogen, lipoproteins and the phenotype of circulating monocytes.

METHODS

The monocytes phenotype, in postmenopausal women (n=26) without history of cardiovascular disease, was determined, by flow cytometry, measuring granularity and CD14, HLA-DR and CD62-L antigens expression. Blood monocytes were divided in CD14+dim monocytes (low CD14 expression) and CD14+bright monocytes (high CD14 expression).

RESULTS

HLA-DR was negatively correlated with hs-CRP and fibrinogen. The relationships between ApoB, LDL/ApoB ratio and CD14 expression was restricted to the CD14+bright monocytes. Blood lipids, i.e. total cholesterol, LDL-c and ApoB were correlated with the granularity of both subsets. CD14+dim monocytes were characterized by a low granularity and CD62-L expression.

CONCLUSIONS

Our data show that fibrinogen and hs-CRP are correlated with a reduced antigen-presenting capacity. Expression of CD14 on CD14+bright monocytes is negatively associated to atherogenic LDL. Blood monocytes granularity was positively correlated with serum lipids indicating that monocytes could uptake modified LDL in circulation and not restricted to subendothelial space.