title: Mucosal T-cell phenotypes in persistent atopic and nonatopic rhinitis show an association with mast cells.
abstract: BACKGROUND
  Allergic rhinitis is characterized by selective expansion of T cell subsets with a CD4+ phenotype. Recently, we identified a subpopulation of nonallergic rhinitis subjects with increased epithelial mast cell and eosinophil populations, suggestive of local mucosal allergy. Previously, T cell subsets have not been characterized in this subselection of nonallergic subjects and furthermore, their relationship to mast cell and basophil effector cells remain unidentified.
  
  
  OBJECTIVE
  To determine if a subpopulation of nonallergic subjects with idiopathic rhinitis (IR) have localized allergy confined to their nasal mucosa by comparing the T cell subsets and major histocompatibility complex (MHC) II expressing cells to persistent allergic rhinitis (PAR). Furthermore, the relationship between T cell subsets and mast cells/basophils was investigated.
  
  
  METHODS
  None of the symptomatic patients in this study were clinically allergen-challenged. Nasal turbinate mucosa was removed from patients with PAR, IR and normal controls. Morphometry was performed on immunostained sections for T cell subset populations including CD3+, CD4+, CD8+, CD25+, CD45RA+, CD45RO+, human leucocyte antigen (HLA)-DRalpha (MHC class II), mast cell tryptase and for basophils.
  
  
  RESULTS
  Subjects with persistent allergic rhinitis differed to normal controls in showing significantly increased numbers of total (CD3+), activated (CD25+) and allergen-naïve (CD45RA+) T lymphocytes in their nasal mucosa (P < 0.025). The naïve CD45RA+ memory T cells correlated to mucosal mast cells in PAR (P = 0.03). IR patients differ to allergic subjects in showing significantly reduced numbers of epithelial HLA-DRalpha+ cells (P = 0.007), but increased numbers of CD8+ lymphocytes (P = 0.02). The CD8+ T cells correlated with mucosal mast cell numbers (P = 0.02). In both rhinitis groups, basophils were present in very low numbers obviating the need for statistical analysis.
  
  
  CONCLUSIONS
  PAR is characterized by increased numbers of CD3+, CD25+ and CD45RA+ T lymphocytes compared with normal mucosa. Allergic and nonallergic rhinitis groups can be separated by significant differences in the number of epithelial antigen presenting cells (APCs) (HLA-DRalpha+) and sub-epithelial activated (CD25+) T cells. Moreover, IR patients do not significantly differ to their allergic counterparts with respect to total (CD3+) and naïve (CD45RA+) T cell numbers, or numbers of epithelial activated (CD25+) lymphocytes. IR subjects show significantly increased numbers of CD8+ lymphocytes compared with control mucosa and although our findings suggest that the initiating inflammatory events may differ, both rhinitis groups show a similarity in pathology involving mucosal mast cells with an association to infiltrating T cells.
authors.affiliation: School of Medical Molecular Science, University Hospital, Queen's Medical Centre, Nottingham NG7 2UH, UK.
authors.forename: D G
authors.initials: DG
authors.lastname: Powe
authors.forename: R S
authors.initials: RS
authors.lastname: Huskisson
authors.forename: A S
authors.initials: AS
authors.lastname: Carney
authors.forename: D
authors.initials: D
authors.lastname: Jenkins
authors.forename: A R
authors.initials: AR
authors.lastname: McEuen
authors.forename: A F
authors.initials: AF
authors.lastname: Walls
authors.forename: N S
authors.initials: NS
authors.lastname: Jones
mesh_terms: D000293:Adolescent; D000328:Adult; D000938:Antigen-Presenting Cells / Q000473:pathology; D001491:Basophils / Q000473:pathology; D002452:Cell Count; D004848:Epithelium / Q000276:immunology; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D016130:Immunophenotyping; D008285:Major Histocompatibility Complex; D008407:Mast Cells / Q000473:pathology*; D008875:Middle Aged; D009297:Nasal Mucosa / Q000276:immunology* / Q000473:pathology; D012220:Rhinitis / Q000276:immunology* / Q000473:pathology; D012221:Rhinitis, Allergic, Perennial / Q000276:immunology* / Q000473:pathology; D016176:T-Lymphocyte Subsets
chemical_list: D006684:HLA-DR Antigens