title: Sensitization to Per a 2 of the American cockroach correlates with more clinical severity among airway allergic patients in Taiwan.
abstract: BACKGROUND
  In Taiwan, 57.5% of asthmatic patients are allergic to cockroaches, which are a major indoor allergen for immunoglobulin E (IgE)-mediated respiratory diseases.
  
  
  OBJECTIVE
  To determine whether sensitization to different cockroach allergenic components correlates with different clinical manifestations and severities.
  
  
  METHODS
  The complementary DNAs (cDNAs) encoding for Per a 1 through 7 and Per a 9 were generated by reverse transcription polymerase chain reaction and cloned into the Escherichia coli expression system. Sixty-four subjects were divided into 3 groups based on the clinical severity of their allergic reaction: those with persistent asthma and rhinitis (AS), those with allergic rhinitis only (AR), and the nonallergic controls (NA). Serum levels of interleukin-8 (IL-8), monocyte chemotactic protein-1 (MCP-1), chemokine (C-C motif) ligand 20 (CCL-20), and granulocyte macrophage colony-stimulating factor (GM-CSF) were measured, and the binding frequencies to each recombinant allergen were examined.
  
  
  RESULTS
  Serum levels of IL-8, MCP-1, and CCL-20 were significantly higher in the AS group than in the AR and NA groups. The numbers of IgE-binding allergens did not correlate with the clinical severity of airway allergy to cockroaches. However, 81% in the AS group had IgE-binding activity to Per a 2, which was significantly higher than that of the AR group (45%, P < .05). In contrast, 80% of AR patients had IgE-binding activity to Per a 9 compared with only 28.5% of AS patients (P < .01).
  
  
  CONCLUSIONS
  Allergens from American cockroaches do not have equal importance in terms of pathogenicity. Sensitization to Per a 2 correlates with more severe airway allergy and elevated proinflammatory chemokines. This may help in selecting target allergens for component resolved diagnosis and immunotherapeutic agents.
authors.affiliation: Department of Education and Research, Taichung Veterans General Hospital, and General Education Center, Overseas Chinese University, Taichung, Taiwan.
authors.forename: Mey-Fann
authors.initials: MF
authors.lastname: Lee
authors.forename: Pei-Peng
authors.initials: PP
authors.lastname: Song
authors.forename: Guang-Yuh
authors.initials: GY
authors.lastname: Hwang
authors.forename: Shyh-Jye
authors.initials: SJ
authors.lastname: Lin
authors.forename: Yi-Hsing
authors.initials: YH
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens / Q000235:genetics / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000503:physiopathology*; D018932:Chemokine CCL2 / Q000097:blood; D054418:Chemokine CCL20 / Q000097:blood; D002648:Child; D003001:Cloning, Molecular; D018450:Disease Progression; D004926:Escherichia coli; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000097:blood; D006801:Humans; D007114:Immunization; D007073:Immunoglobulin E / Q000097:blood; D019476:Insect Proteins / Q000235:genetics / Q000276:immunology*; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D008875:Middle Aged; D010526:Periplaneta / Q000276:immunology*; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D012130:Respiratory Hypersensitivity / Q000276:immunology / Q000503:physiopathology; D013624:Taiwan
chemical_list: D000485:Allergens; C111835:CCL2 protein, human; D018932:Chemokine CCL2; D054418:Chemokine CCL20; D019476:Insect Proteins; D016209:Interleukin-8; C572508:Per a 2 allergen, Periplaneta americana; D011994:Recombinant Proteins; D007073:Immunoglobulin E; D016178:Granulocyte-Macrophage Colony-Stimulating Factor