Toll-like receptors 2 and 4 and the cryopyrin inflammasome in normal pregnancy and pre-eclampsia

Objective  Pre-eclampsia involves a maternal inflammatory response that differs from both normal pregnancy and normotensive intrauterine growth restriction (IUGR). Our objective was to examine neutrophil Toll-like receptor (TLR), cryopyrin, nuclear factor-κB (NF-κB) subunit and interleukin-1β (IL-1β), and inflammatory cytokine profiles in women with pre-eclampsia or normotensive IUGR, as well as in normal pregnancy and non-pregnancy controls. Design and method  A case–control study was performed. We examined the messenger RNA (mRNA) and protein expressions of TLR4 and TLR2, mRNA levels of cryopyrin, IL-1β, NF-κB subunits p50 and p65, as well as maternal serum inflammatory cytokine profiles (IL-2, IL-6, tumour necrosis factor-α [TNF-α], interferon-γ [IFN-γ] and IL-10) in women with and without pre-eclampsia using real-time reverse transcription polymerase chain reactions, flow cytometry and multiplex immunoassays. Setting  A single tertiary maternity hospital in Vancouver, Canada. Population  Women with early-onset pre-eclampsia (<34 weeks of gestation, n = 25), women with late-onset pre-eclampsia (≥34+0 weeks of gestation, n = 25), women with normotensive IUGR (n = 25), women with normal pregnancy (n = 75) and non-pregnancy (n = 25) controls. Results  Women with pre-eclampsia (as a single combined group of early- and late-onset, and particularly in women with early-onset pre-eclampsia) had increased TLR2 and TLR4 mRNA and protein expressions elevated cryopyrin, NF-κB subunit, and IL-1β mRNA expression, and TNF-α:IL-10 and IL-6:IL-10 ratios compared with other groups. Conclusions  These data suggest that TLRs and cryopyrin may modulate the innate immune response of the maternal syndrome of pre-eclampsia, and might also trigger the differential inflammatory response existing between early onset pre-eclampsia and normotensive IUGR.