Blocking antibody is generated in allergic rhinitis patients during specific immunotherapy using standardized Japanese cedar pollen extract.
BACKGROUND
Japanese cedar pollen is by far the most important cause of allergic rhinitis in Japan. In this study, we assessed the induction of blocking antibody during specific immunotherapy (SIT) using a recently standardized allergen extract from Japanese cedar pollen.


METHODS
Basophils from nonallergic subjects were passively sensitized with serum samples prepared from pollinosis patients before and after SIT; all patients showed good clinical efficacy. The cells were then stimulated with the standardized allergen, and histamine release was measured. In most experiments, the basophil stimulation buffer contained 1% serum.


RESULTS
Pollinosis patients' sera obtained both before and after SIT showed essentially similar sensitizing capacity for basophils. Basophil degranulation in response to a relatively low concentration of pollen extract was effectively suppressed by addition of post-SIT serum samples, indicating the presence of blocking antibody. The blocking antibody was IgG, and its potency varied widely among the donor patients.


CONCLUSIONS
The standardized allergen extract from Japanese cedar pollen is useful not only for clinical application in SIT, but also for testing for induction of blocking antibody during SIT.
Kawakami
Ayako
A
Department of Allergy and Rheumatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
Koketsu
Rikiya
R
Suzukawa
Maho
M
Nagao
Mizuho
M
Hiraguchi
Yukiko
Y
Tokuda
Reiko
R
Fujisawa
Takao
T
Nagase
Hiroyuki
H
Ohta
Ken
K
Yamamoto
Kazuhiko
K
Yamaguchi
Masao
M
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology; D018926:Anti-Allergic Agents / Q000627:therapeutic use; D000906:Antibodies / Q000097:blood*; D001491:Basophils / Q000276:immunology; D002648:Child; D032485:Cryptomeria / Q000276:immunology*; D005260:Female; D006801:Humans; D007167:Immunotherapy; D007564:Japan; D008297:Male; D008517:Phytotherapy; D010936:Plant Extracts / Q000627:therapeutic use; D011058:Pollen / Q000737:chemistry / Q000276:immunology*; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology / Q000628:therapy*
D000485:Allergens; D018926:Anti-Allergic Agents; D000906:Antibodies; D010936:Plant Extracts