[Distribution of IgG subclass of anti-myeloperoxidase antibodies in sera from patients with propylthiouracil induced vasculitis].
OBJECTIVE
To investigate the distribution of IgG subclass of anti-myeloperoxidase (MPO) antibodies, a kind of antineutrophil cytoplasmic autoantibody (ANCA), in sera from patients with propylthiouracil (PIU)-induced vasculitis.


METHODS
Serum samples were collected from 12 patients with PIU-induced MPO ANCA positive vasculitis, both sera of active and remission phases were collected from 10 of which, and only serum of active phase was collected from 2 of which. Anti-MPO IgG subclasses were detected by antigen-specific ELISA. The distribution of anti-MPO IgG subclasses in PIU-induced vasculitis was compared with that in primary vasculitis.


RESULTS
Anti-MPO IgG3 subclass was not detected in the sera from both active and remission phases of PIU-induced vasculitis. In the active phase the following anti-MPO IgG subclasses were found: IgG1 (12/12, 100%), IgG2 (1/12, 66.7%), and IgG4 (7/12, 58.3%). In the remission phase, the following anti-MPO IgG subclasses were found: IgG1 (9/10, 90%), IgG2 (4/10, 40%), and IgG4 (2/10, 20%). The titer of anti-MPO IgG4 subclass remained high in the remission phase in primary vasculitis; however, it decreased significantly after the cessation of PIU use in PIU-induced vasculitis.


CONCLUSIONS
The distribution of anti-MPO IgG subclasses in the sera of the patients with PIU-induced vasculitis is different from that of the patients with primary vasculitis. The higher titer pf MPO-ANCA in the sera of the patients with PIU-induced vasculitis may be associated with the repeated PIU stimulation.
Gao
Ying
Y
Department of Endocrionology, Peking University First Hospital, Beijing 100034, China.
Zhao
Ming-hui
MH
Guo
Xiao-hui
XH
Zhang
Ying
Y
Wang
Hai-yan
HY
D000293:Adolescent; D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood* / Q000145:classification; D002648:Child; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D008297:Male; D008875:Middle Aged; D011441:Propylthiouracil; D014657:Vasculitis / Q000097:blood* / Q000139:chemically induced
D019268:Antibodies, Antineutrophil Cytoplasmic; D007074:Immunoglobulin G; D011441:Propylthiouracil