title: Developing patterns of T cell memory to environmental allergens in the first two years of life.
abstract: Several recent studies have demonstrated cord blood mononuclear cell (CBMC) proliferation in response to food and inhalant allergens, suggesting that initial T-cell-priming may occur in utero. The findings below from an ongoing prospective study on 60 subjects provide initial information on the nature of accompanying T cell cytokine responses. We demonstrate CBMC proliferation following culture with house dust mite and ovalbumin (OVA) in 47 and 42% of subjects, respectively, compared to an overall rate of 3% for tetanus toxoid; the frequencies of these responses were comparable in neonates with and without atopic family history (FH). With the exception of IL-10, analysis of cytokine responses in allergen-stimulated cultures of CBMCs required the use of semiquantitative RT-PCR, which revealed low-level IL-4 and/or IL-5 mRNA production, in particular a 50% IL-5 response rate to OVA in FH-positive neonates. IFN-gamma responses were less frequent and required higher PCR cycle numbers for detection. Preliminary analysis of culture supernatants from a subgroup of CBMCs indicate high-level allergen-specific IL-10 responses in both FH-negative and -positive subjects, detectable by ELISA. Parallel PCR studies on MCs from 27 children (mean age 18 months) indicated a clear segregation at this age on the basis of FH, with Th0-like or mixed Th1/Th2 responses (IL-5 plus IFN-gamma) which were mainly restricted to the FH-positive group.
authors.affiliation: Division of Cell Biology, TVW Telethon Institute for Child Health Research, West Perth, Australia.
authors.forename: S L
authors.initials: SL
authors.lastname: Prescott
authors.forename: C
authors.initials: C
authors.lastname: Macaubes
authors.forename: A
authors.initials: A
authors.lastname: Yabuhara
authors.forename: T J
authors.initials: TJ
authors.lastname: Venaille
authors.forename: B J
authors.initials: BJ
authors.lastname: Holt
authors.forename: W
authors.initials: W
authors.lastname: Habre
authors.forename: R
authors.initials: R
authors.lastname: Loh
authors.forename: P D
authors.initials: PD
authors.lastname: Sly
authors.forename: P G
authors.initials: PG
authors.lastname: Holt
mesh_terms: D000485:Allergens / Q000276:immunology*; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000235:genetics; D007156:Immunologic Memory; D007223:Infant; D007231:Infant, Newborn; D007371:Interferon-gamma / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000485:Allergens; D007371:Interferon-gamma