title: Transcription of var genes other than var2csa in Plasmodium falciparum parasites infecting Mozambican pregnant women.
abstract: BACKGROUND
  Increased susceptibility to Plasmodium falciparum infection during pregnancy has been attributed to the accumulation of infected erythrocytes in the placenta. This phenomenon is mediated by a var gene coding for VAR2CSA, which adheres to chondroitin sulphate A. However, the contribution of parasites transcribing other var genes to maternal infections has not been well characterized.
  
  
  METHODS
  Transcription of var2csa and var groups A, B, and C was measured by real-time polymerase chain reaction in 30 placental and 21 peripheral P. falciparum isolates from pregnant women and in 42 isolates from nonpregnant adults and children. Associations of infections with non-var2csa isolates with maternal parasitemia and immune responses were assessed.
  
  
  RESULTS
  Placental parasites showed the highest levels of var2csa. ABC var genes were transcribed by 20 (67%) of 30 placental isolates and were associated with higher parasitemia compared with infections by parasites only transcribing var2csa (P = .004). Peripheral isolates from pregnant women transcribed ABC var genes at levels similar to those of parasites infecting nonpregnant adults with clinical malaria (P[varA] = .420, P[varB] = .808, and P[varC] = .619).
  
  
  CONCLUSIONS
  Transcripts of var2csa are abundant in pregnancy-associated P. falciparum infections; however, ABC var types are also common, especially in peripheral blood, with transcription levels similar to those of infections out of pregnancy. These findings are of interest for the design of malaria vaccines for pregnant women.
authors.affiliation: Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain.
authors.forename: Eduard
authors.initials: E
authors.lastname: Rovira-Vallbona
authors.forename: Carlota
authors.initials: C
authors.lastname: Dobaño
authors.forename: Azucena
authors.initials: A
authors.lastname: Bardají
authors.forename: Pau
authors.initials: P
authors.lastname: Cisteró
authors.forename: Cleofé
authors.initials: C
authors.lastname: Romagosa
authors.forename: Elisa
authors.initials: E
authors.lastname: Serra-Casas
authors.forename: Llorenç
authors.initials: L
authors.lastname: Quintó
authors.forename: Quique
authors.initials: Q
authors.lastname: Bassat
authors.forename: Betuel
authors.initials: B
authors.lastname: Sigaúque
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Alonso
authors.forename: Jaume
authors.initials: J
authors.lastname: Ordi
authors.forename: Clara
authors.initials: C
authors.lastname: Menéndez
authors.forename: Alfredo
authors.initials: A
authors.lastname: Mayor
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000953:Antigens, Protozoan / Q000096:biosynthesis* / Q000235:genetics; D001769:Blood / Q000469:parasitology; D002675:Child, Preschool; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016778:Malaria, Falciparum / Q000469:parasitology*; D008875:Middle Aged; D010920:Placenta / Q000469:parasitology; D010963:Plasmodium falciparum / Q000235:genetics* / Q000302:isolation & purification; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000469:parasitology*; D015800:Protozoan Proteins / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D055815:Young Adult
chemical_list: D000953:Antigens, Protozoan; D015800:Protozoan Proteins; C512601:VAR2CSA protein, Plasmodium falciparum; C085731:erythrocyte membrane protein 1, Plasmodium falciparum