title: Effect of age and degree of immune activation on cytochrome P450 3A4 activity after influenza immunization.
abstract: OBJECTIVE
  To measure age- or sex-related changes in cytochrome P450 (CYP) activity secondary to influenza vaccination.
  
  
  METHODS
  Open-label, single-dose study.
  
  
  METHODS
  General clinical research center at a university hospital.
  
  
  METHODS
  Fifteen healthy volunteers aged 22-51 years.
  
  
  METHODS
  Each subject was given an erythromycin breath test (ERMBT) to measure CYP3A4 activity before influenza immunization and again on day 7 after immunization. Blood was drawn before immunization and on day 28 after immunization to measure influenza antibody concentrations.
  
  
  RESULTS
  Age of subject and change in ERMBT results after influenza immunization were correlated (correlation coefficient -0.624, p < 0.015). However, no correlations could be made between antibody concentrations after influenza immunization or change in antibody concentrations from baseline and age.
  
  
  CONCLUSIONS
  Decreases in CYP3A4 activity after influenza immunization are associated with increasing age. The decreases in CYP3A4 activity, however, are not associated with influenza antibody concentrations. This study bears repeating in an older cohort since the study sample did not include elderly individuals.
authors.affiliation: School of Pharmacy, University of Wisconsin, Madison 53705-2222, USA. mshayney@pharmacy.wisc.edu
authors.forename: Mary S
authors.initials: MS
authors.lastname: Hayney
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Buck
mesh_terms: D000328:Adult; D000367:Age Factors; D000917:Antibody Formation; D001944:Breath Tests; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004917:Erythromycin; D005260:Female; D006801:Humans; D007252:Influenza Vaccines / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012737:Sex Factors
chemical_list: D007252:Influenza Vaccines; D004917:Erythromycin; D003577:Cytochrome P-450 Enzyme System; C104464:CYP3A protein, human; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human