title: Gelatin-specific cellular immune responses persist for more than 3 years after priming with gelatin containing DTaP vaccine.
abstract: BACKGROUND
  Gelatin-specific cell-mediated immunity develops in subjects inoculated with gelatin containing DTaP vaccine. However, it is not yet known whether such established sensitization to gelatin disappears or persists with time.
  
  
  OBJECTIVE
  The aim of this study was to follow the patients with gelatin sensitization elicited by DTaP vaccination for their lymphocyte responsiveness and IgE, IgG antibody specific to gelatin over several years and to compare the activities with those at the time of enrollment into the study.
  
  
  METHODS
  We studied 28 subjects who developed positive lymphocyte proliferation test (LPT) after receiving gelatin containing DTaP vaccine and eight subjects who had a negative LPT after inoculation of non-gelatin DTaP. Determination of IgE, IgG antibodies and specific lymphoproliferative response directed against gelatin were performed at enrollment and on follow up.
  
  
  RESULTS
  None of the subjects had antibody to gelatin at enrollment and none developed gelatin IgE or IgG during follow-up. There was no significant difference in the SIs of the subjects receiving gelatin DTaP (P = 0.150, 95% CI, -0.198-0.032), whereas lymphocyte activity to gelatin increased between enrollment and follow-up in the subjects with non-gelatin DTaP (P = 0.011, 95% CI, 0.063-0.338).
  
  
  CONCLUSIONS
  Gelatin-specific lymphocyte activity persists at comparable levels for more than 3 years in subjects who acquire a positive LPT response to gelatin after receiving primary DTaP vaccine containing gelatin. Furthermore, five out of eight subjects initially with negative LPT to gelatin have been shown to acquire specific LPT with time.
authors.affiliation: Pediatric Allergy and Infectious Diseases Society of Sapporo, Hokkaido, Japan. tkuma@mb.infosnow.ne.jp
authors.forename: T
authors.initials: T
authors.lastname: Kumagai
authors.forename: M
authors.initials: M
authors.lastname: Kamada
authors.forename: C
authors.initials: C
authors.lastname: Igarashi
authors.forename: K
authors.initials: K
authors.lastname: Yuri
authors.forename: H
authors.initials: H
authors.lastname: Furukawa
authors.forename: N
authors.initials: N
authors.lastname: Nagata
authors.forename: A
authors.initials: A
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Okui
authors.forename: S
authors.initials: S
authors.lastname: Yano
mesh_terms: D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000276:immunology*; D004342:Drug Hypersensitivity / Q000276:immunology*; D005260:Female; D005780:Gelatin / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D007223:Infant; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008297:Male; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines; D007074:Immunoglobulin G; D007073:Immunoglobulin E; D005780:Gelatin