Hyperexpression of the high-affinity IgE receptor-beta chain in chronic allergic keratoconjunctivitis.
OBJECTIVE
Although the existence of Fc(epsilon)RI-alphabetagamma(2) and Fc(epsilon)RI-alphagamma(2) receptor subtypes was reported, there has been no direct evidence of these two subtypes of Fc(epsilon)RI in vivo. To investigate the existence of these two subtypes of Fc(epsilon)RI in vivo, the authors evaluated the expression of Fc(epsilon)RI-beta in the giant papillae of chronic allergic conjunctivitis and compared the expression level of Fc(epsilon)RI-beta with control conjunctivae using the anti-human Fc(epsilon)RI-beta antibody.


METHODS
Fc(epsilon)RI-beta expression in giant papillae obtained from patients with atopic keratoconjunctivitis and vernal keratoconjunctivitis in control conjunctivae was evaluated by immunohistochemistry using anti-Fc(epsilon)RI-beta, -alpha, -gamma, and anti-human mast cell tryptase, anti-chymase, anti-basophil, and anti-CD1a antibodies.


RESULTS
Statistical analyses revealed that the densities of Fc(epsilon)RI-beta(+) cells, Fc(epsilon)RI-alpha(+) cells, tryptase(+) cells, and Fc(epsilon)RI-beta(+)/tryptase(+) cells were significantly increased in giant papillae compared with controls. There were two types of Fc(epsilon)RI (alphabetagamma(2) and alphagamma(2)) on the mast cells of the giant papillae. The ratio of the Fc(epsilon)RI-beta(+) cell number/Fc(epsilon)RI-alpha(+) cell number in the giant papillae (0.69 +/- 0.08 [mean +/- SD]) was significantly higher than that of the controls (0.07 +/- 0.16). Fc(epsilon)RI-beta/tryptase double immunostaining revealed that 81% +/- 13% of tryptase(+) cells expressed Fc(epsilon)RI-beta. Fc(epsilon)RI-beta(+) cells were preferentially localized within and around epithelial tissue. The authors also found that Fc(epsilon)RI-beta was expressed by basophils but not by Fc(epsilon)RI-alphagamma(2)-positive Langerhans cells in the giant papillae samples.


CONCLUSIONS
Preferential Fc(epsilon)RI-beta expression observed in the mast cells and basophils of giant papillae suggests important roles of Fc(epsilon)RI-beta in the pathophysiology of atopic keratoconjunctivitis and vernal keratoconjunctivitis.
Matsuda
Akira
A
Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan. akimatsu@koto.kpu-m.ac.jp
Okayama
Yoshimichi
Y
Ebihara
Nobuyuki
N
Yokoi
Norihiko
N
Hamuro
Junji
J
Walls
Andrew F
AF
Ra
Chisei
C
Hopkin
Julian M
JM
Kinoshita
Shigeru
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D001491:Basophils / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count; D002908:Chronic Disease; D003228:Conjunctiva / Q000378:metabolism; D003233:Conjunctivitis, Allergic / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D008407:Mast Cells / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D017455:Receptors, IgE / Q000378:metabolism*; D055815:Young Adult
C502447:MS4A2 protein, human; D017455:Receptors, IgE