Interferon-gamma receptor beta-chain expression and formation of alpha- and beta-chain complexes after receptor conjugation on human peripheral eosinophils.
BACKGROUND
It has been unclear whether or not the interferon-gamma receptor (IFN-gammaR) on human peripheral eosinophils is completely functional. Accordingly, we examined the expression of IFN-gammaR alpha- and beta-chains and the association of the two chains after binding of IFN-gamma to the receptor.


METHODS
Peripheral blood eosinophils were obtained from 8 patients (bronchial asthma, n=6, and hypereosinophilic syndrome, n=2), and expression of the alpha- and beta-chain was investigated by flow cytometry with specific antibodies. Expression of mRNA for the alpha- and beta-subunits was also investigated by the reverse transcriptase-polymerase chain reaction.


RESULTS
Eosinophils from all the patients were positive for both the alpha- and beta-chains by flow cytometry. In addition, mRNA for both chains was detected by the polymerase chain reaction. Furthermore, coprecipitation of the alpha- and beta-chains was only found after eosinophil stimulation with IFN-gamma.


CONCLUSIONS
Human peripheral eosinophils apparently express both the alpha- and beta-chains of the IFN-gammaR, and the two chains may only form the receptor complex after ligand binding.
Department of Pediatrics, Sakura Hospital, Toho University School of Medicine, Sakura, Japan.
C
C
Ishiharu
K
K
Ochiai
M
M
Kagami
G
G
Matsuyama
N
N
Koya
H
H
Tomioka
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000097:blood / Q000276:immunology; D001483:Base Sequence; D002648:Child; D017931:DNA Primers / Q000235:genetics; D004804:Eosinophils / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000097:blood / Q000276:immunology; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D011487:Protein Conformation; D012333:RNA, Messenger / Q000097:blood / Q000235:genetics; D017471:Receptors, Interferon / Q000097:blood* / Q000737:chemistry / Q000235:genetics; D011994:Recombinant Proteins; D000096743:Interferon gamma Receptor
D017931:DNA Primers; D007371:Interferon-gamma; D012333:RNA, Messenger; D017471:Receptors, Interferon; D011994:Recombinant Proteins; D000096743:Interferon gamma Receptor