A role for the novel cytokine RANTES in pregnancy and parturition

Objective: RANTES (regulated on activation, normal T cell expressed and secreted), a potent and versatile chemokine, is capable of attracting monocytes, lymphocytes, basophils, and eosinophils. This cytokine has been implicated in the regulation of the inflammatory response and in the recruitment of macrophages to the implantation site in early pregnancy. RANTES messenger ribonucleic acid and protein have been detected in fetal tissue and first-trimester trophoblast in response to bacterial endotoxin. The purpose of this study was to determine whether intrauterine infection, parturition (preterm and term), and gestational age affect the amniotic fluid concentrations of RANTES in human pregnancy. Study Design: A cross-sectional study was designed to examine the relationship between labor, microbial invasion of the amniotic cavity, gestational age, and RANTES expression in amniotic fluid. Amniotic fluid was obtained from 214 women in the following groups: (1) midtrimester (n = 22), (2) preterm labor with intact membranes in the presence (n = 20) or absence (n = 74) of microbial invasion of the amniotic cavity, (3) term, not in labor (n = 44) and term, in labor in the presence (n = 27) and absence (n = 27) of microbial invasion of the amniotic cavity. Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture for microorganisms. RANTES concentrations were determined by use of a sensitive and specific immunoassay. Results: (1) Amniotic fluid RANTES concentrations decrease with advancing gestational age (r = 0.43; P < .01). (2) Labor at term was associated with an increase in median concentrations of RANTES (labor—median, 8.4 pg/mL; range