RANTES and developmental defects of enamel in children: A Brazilian prenatal cohort (BRISA)

Objective: Little is known about the effect of maternal immunological factors on the etiology of developmental defects of enamel (DDE). RANTES (Regulated on Activation Normal T Cell Expressed and Secreted) is a chemokine produced by fibroblasts, lymphoid and epithelial mucosa cells in response to various external stimuli. Despite its importance for embryogenesis, RANTES expression has been demonstrated in multiple diseases characterized by inflammation, tumor and immune response, and wound healing. We hypothesized that altered levels of RANTES during pregnancy are associated with the immune and inflammatory response in women, which could lead to the occurrence of DDE in utero (DDE-iu), directly or mediated by preterm birth. Therefore, this study aimed to evaluate the direct and indirect effects of serum levels of RANTES in pregnant women in the occurrence of DDE-iu in children. Methods: This is a longitudinal case-control study. The mothers and their children (327) were evaluated in three moments: prenatal care, post childbirth, and when the child was between 12.3 and 36 months of age. The analysis was performed with structural equation modeling, estimating the standardized coefficient (SC), adopting α = 5%. Results: There was a direct and negative effect of RANTES on the outcome (SC = -0.137; p = 0.022). This association was not mediated by preterm birth (SC = 0.007; P = 0.551). When considering the specific types of DDE-iu, RANTES had a direct effect on hypoplasia (SC = -0.190; p = 0.007), but not on opacity (SC = 0.343; p = 0.074). Conclusion: Lower serum levels of RANTES may contribute to a higher number of teeth with DDE-iu, specifically hypoplasia. However, more evidence supported by clinical, laboratory and epidemiological studies is still needed.