PP064. M1 Monocyte subpopulation is associated with pro-inflammatory cytokineproduction in pregnant women with preeclampsia

Abstract

Monocytes from peripheral blood of pregnant women with preeclampsia are endogenously activated and secrete high levels of free radicals and inflammatory cytokines. This study aimed at evaluating whether the inflammatory state of monocytes observed in preeclampsia is associated with the polarization of monocyte to M1 profile in peripheral blood, correlating the expression of surface receptors CD64, TLR2, TLR4, and CD163 and CD206 with cytokine production. We studied 90 pregnant women, 30 normotensive and 60 with preeclampsia, matched for gestational age. Peripheral blood monocytes obtained from normotensive pregnant or preeclamptic pregnant women were cultured for 18h, and the expression of surface receptors on M1 inflammatory monocyte subpopulation (TLR2, TLR4 and CD64) and M2 suppressor monocyte subpopulation (CD163 and CD206) were evaluated by flow cytometry, using specific monoclonal antibodies, labeled with fluorochromes. The values were expressed as ??the mean fluorescence intensity. Moreover, the production of proinflammatory cytokines associated with M1 profile (TNF-α, IL-12p70 and IL-23) and the anti-inflammatory cytokine associated with M2 profile (IL-10) were evaluated in the monocyte supernatant of culture by enzyme immunoassay. Results were analyzed using nonparametric tests with significance level set at 5%. The expression of CD4 and TLR4 on monocyte surface, from women with preeclampsia was significantly higher, while the expression of CD163 and CD206 was significantly decreased compared with normotensive pregnant women, suggesting the predominance of monocyte M1 profile. Endogenous production of TNF-α, IL-12p70 and IL-23 by monocytes was increased, while synthesis of IL-10 was lower in women with preeclampsia compared with normotensive pregnant women. Positive correlations between TLR4 and CD64 (r=0.5849), TLR4 and TNF-α (r=0.5126) or TLR4 and IL-23 (r=0.8095), as well as between CD64 and TNF-α (r = 0.7133) or CD64 and IL-23 (r = 0.6051) were observed in the preeclamptic group. The results confirm the activated state of monocytes from women with preeclampsia by increased production of proinflammatory cytokines and the expression of receptors characteristic of the M1 subpopulation. This study provides evidence that monocytes from women with preeclampsia are classically activated and the systemic inflammatory environment may differentiate and polarize these cells to the M1 profile. CNPq, FAPESP 2009/11924-3 and 2010/20207-0.