title: Impact of placental Plasmodium falciparum malaria infection on the Cameroonian maternal and neonate's plasma levels of some cytokines known to regulate T cells differentiation and function.
abstract: BACKGROUND
  The impact of placental malaria (PM) infection on the expression profile of some cytokines known to regulate T cell differentiation and function and their influence on birth weight remain unclear. Moreover, there are no reports showing the relationship between PM and IL-27 or IL-28A. This study therefore sought to investigate whether placental P. falciparum infection alters the expression profile of the cytokines IL-28A, IL-27, IL-17E and IL-6 in mothers and their new born.
  
  
  METHODS
  In a cross-sectional study conducted between 2013 and 2015 in Yaoundé, Cameroon, peripheral, placental and cord blood samples were collected from 108 women at delivery. Parasitaemia was determined microscopically and haemoglobin levels determined using a Coulter counter. Plasma levels of cytokines (IL-28A, IL-27, IL-17E and IL-6) were measured by Luminex magnetic screening assay.
  
  
  RESULTS
  Malaria parasite density in placenta impression smear associated negatively with maternal haemoglobin level (P < 0.0001) and baby birth weight (P = 0.016). While IL-17E, IL-27 and IL-28A levels were significantly higher in placental and cord plasma than in peripheral (P < 0.0001, < 0.001 and P = 0.026, respectively), an opposite relationship was observed with IL-6 (P = 0.0018). Multivariate analysis confirmed results of univariate analysis where the presence of malaria parasites or pigments in placenta tissue impression smears correlated with decrease levels of maternal IL-17E, IL-27 and IL-28A and neonate levels of IL-28A and IL-17E (0.0001 ≤ P ≤ 0.02). Placental and peripheral parasitaemias also correlated positively with peripheral plasma levels of IL-6 (rs= 0.18, P = 0.05 and rs= 0.17, P = 0.07, respectively). In addition, high maternal haemoglobin level associated with increasing levels of IL-17E, IL-27 and IL-28A in peripheral plasma (0.002 ≤ P ≤ 0.018) and high placental and cord plasma levels of these cytokines associated with increasing birth weight (0.0001 ≤ P ≤ 0.0027).
  
  
  CONCLUSIONS
  Placental malaria downregulates maternal plasma levels of IL-17E, IL-27 and IL-28A and neonates' plasma levels of IL-17E and IL-28A cytokines, which could help for parasite clearance and increase child birth weight. The study is expected to provide leads that should help identify potential biomarkers for improved birth weight and therapeutic interventions.
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Jean Claude
authors.initials: JC
authors.lastname: Djontu
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Stalone
authors.initials: S
authors.lastname: Siewe Siewe
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Yolande Delphine
authors.initials: YD
authors.lastname: Mpeke Edene
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Benderli Christine
authors.initials: BC
authors.lastname: Nana
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Edwige Vanessa
authors.initials: EV
authors.lastname: Chomga Foko
authors.affiliation: The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.|Department of Biochemistry of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.
authors.forename: Jude Daiga
authors.initials: JD
authors.lastname: Bigoga
authors.affiliation: The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon.
authors.forename: Rose F G
authors.initials: RF
authors.lastname: Leke
authors.affiliation: Department of Animal Biology and Physiology of the Faculty of Sciences, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon. megnekor@yahoo.fr.|The Biotechnology Center, University of Yaounde I, P.O. Box 3851, Messa, Yaoundé, Cameroon. megnekor@yahoo.fr.
authors.forename: Rosette
authors.initials: R
authors.lastname: Megnekou
mesh_terms: D000293:Adolescent; D000328:Adult; D002163:Cameroon; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D007108:Immune Tolerance; D007231:Infant, Newborn; D016778:Malaria, Falciparum / Q000473:pathology*; D010922:Placenta Diseases / Q000473:pathology*; D010949:Plasma / Q000737:chemistry; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000473:pathology*; D013601:T-Lymphocytes / Q000276:immunology*; D055815:Young Adult
chemical_list: D016207:Cytokines
keywords: Birth weight; Cameroon; Cytokines; Placental malaria; Plasmodium falciparum; Pregnant women