W105 - The Effect of CCD Inhibition on Antigen-specific Ige Test Results in Multiple Allergen Simultaneous Test Using Advansure Alloscreen max108 Panel

Hyeyoung Lee, Laboratory Medicine – Department of Laboratory Medicine – International St. Mary’s Hospital, College of Medicine, Catholic Kwandong University, Incheon, Korea; Kyungcheol Song – Department of Laboratory Medicine – International St. Mary’s Hospital, College of Medicine, Catholic Kwandong University, Incheon, Korea; Jiwoo Kim – Department of Laboratory Medicine – International St. Mary’s Hospital, College of Medicine, Catholic Kwandong University, Incheon, Korea; Jehyun Koo – Department of Laboratory Medicine – International St. Mary’s Hospital, College of Medicine, Catholic Kwandong University, Incheon, Korea

Abstract Text:

Introduction: We investigated how Cross-reactive carbohydrate determinants (CCD) inhibition actually affects various allergen-specific IgE results in a newly introduced multiple allergen simultaneous test, AdvanSure AlloScreen MAX108 Panel (LG CHEM, Korea).

Methods: Sera from 31 patients with positive CCD antigen (grade ≥ 1) in AdvanSure AlloScreen Max108 panel was included. Patients were stratified based on sIgE to CCD classes 1-3, (n=27, CCD-low) vs. classes 4-6, (n=4, CCD-high). All samples were treated with ProGlycAn CCD-blocker (ProGlycAn, Austria) at a concentration of 20 ug/ml and additionally at 40 ug/ml in high CCD.

Results: All 27 CCDs in CCD-low sera negatively converted, but none of CCDs in CCD-high sera when treated with 20 μg/ml. The positive rates for foodstuffs and pollens were significantly higher in CCD-high than CCD-low (foodstuffs 55.0% (110/200) vs 25.1% (279/1113), pollens 97.7% (125/128) vs 62.7% (511/815), p < 0.0001). The rates of the sIgEs turned negative after CCD inhibition showed a significant difference only in pollens (32.8% (41/125) in CCD-high vs 75.0% (383/511) in CCD-low (p < 0.0001). In CCD high group, there was no significant difference in negative conversion rates when treated with the concentration of 20 ug/ml and concentration of 40 ug/ml for all allergens (46.3%, 119/257 vs 54.1%, 139/257). However, the pollen group showed a significant difference (32.8%, 41/125 for 20 ug/ml vs 45.6%, 57/125 for 40 ug/ml, p = 0.0386).

Conclusions: CCD-blocker treatment in sample can reduce the false positive response in CCD-low sera, but, the negative conversion rates after CCD inhibition was different depending on the allergens.