title: Peripheral blood antigen presenting cell responses in otitis-prone and non-otitis-prone infants.
abstract: Stringently defined otitis-prone (sOP) children represent a new classification of the otitis-prone condition. Previous studies showed dysfunction in Ab, B-cell memory and T-cell memory responses. We sought to determine whether there are defects in numbers, phenotype and/or function of professional APC in the peripheral blood of sOP infants. APC phenotypic counts, MHC II expression and intracellular cytokine levels were determined in response to TLR7/8 (R848) stimulation by flow cytometry. Innate immune mRNA expression was measured using RT-PCR and cytokines were measured using Luminex technology. Significant (P < 0.05) increases in the phenotypic counts of monocytes and conventional dendritic cells but not plasmacytoid DCs were observed in sOP compared with non-otitis-prone (NOP) age-matched infants. No significant differences in APC activation or function were observed. Expression of various TLRs, intracellular signaling molecules and downstream cytokines was also not found to be significantly different between sOP and NOP infants. Higher numbers of APCs in sOP infants suggest the possibility of a persistent mucosal inflammatory status. Transcriptional and cytokine profiles of PBMCs among sOP infants suggest their systemic innate responses are not different compared to NOP infants.
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester Regional Health System, 1425 Portland Ave, Rochester, NY, USA.
authors.forename: Naveen
authors.initials: N
authors.lastname: Surendran
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester Regional Health System, 1425 Portland Ave, Rochester, NY, USA.
authors.forename: Ted
authors.initials: T
authors.lastname: Nicolosi
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester Regional Health System, 1425 Portland Ave, Rochester, NY, USA.
authors.forename: Ravinder
authors.initials: R
authors.lastname: Kaur
authors.affiliation: Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester Regional Health System, 1425 Portland Ave, Rochester, NY, USA michael.pichichero@rochesterregional.org.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Pichichero
mesh_terms: D000938:Antigen-Presenting Cells / Q000187:drug effects / Q000276:immunology*; D001773:Blood Cells / Q000187:drug effects / Q000276:immunology*; D002675:Child, Preschool; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007113:Immunity, Innate; D016130:Immunophenotyping; D007223:Infant; D008297:Male; D010031:Otitis / Q000175:diagnosis / Q000276:immunology*; D011446:Prospective Studies; D051199:Toll-Like Receptor 7 / Q000819:agonists; D051200:Toll-Like Receptor 8 / Q000819:agonists
chemical_list: D007093:Imidazoles; C495348:TLR7 protein, human; C495349:TLR8 protein, human; D051199:Toll-Like Receptor 7; D051200:Toll-Like Receptor 8; C402365:resiquimod
keywords: Dendritic cell; infant innate immunity; innate transcriptome; recurrent otitis media; stringently otitis prone