Inhibition of ongoing immunoglobulin production by eosinophil cationic protein.
The effect of eosinophil cationic protein (ECP) upon ongoing immunoglobulin (Ig) production and proliferation in human B cells was studied. ECP inhibited Ig production by the human lymphoblastoid cell lines, CBL and GM-1056, in a dose-dependent fashion. In contrast, proliferation was not affected. This ECP-induced inhibition of Ig production was specific, since inhibition was blocked by anti-ECP serum but not by control serum. Interleukin (IL)-4 did not affect Ig production by CBL or GM-1056 cells; however, IL-4 reversed ECP-induced inhibition of Ig production and this reverse was blocked by anti-IL-4 antibody but not by control antibody. In contrast, other cytokines, including IL-1 beta, IL-2, IL-3, IL-5, IL-6, interferon (IFN)-alpha, and IFN-gamma, failed to reverse inhibition. ECP also inhibited spontaneous Ig production (IgM, IgG1, IgG2, IgG3, IgG4, and IgA) by tonsillar large activated B cells without affecting proliferation. This inhibition was also blocked by anti-ECP serum but not by control serum and was reversed by IL-4 specifically. These results indicate that ECP may play an important role in B cell responses.
Kimata
H
H
Department of Pediatrics, Faculty of Medicine, Kyoto University Hospital, Japan.
Yoshida
A
A
Ishioka
C
C
Jiang
Y
Y
Mikawa
H
H
D000917:Antibody Formation / Q000187:drug effects*; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D001798:Blood Proteins / Q000494:pharmacology*; D002460:Cell Line; D047091:Eosinophil Granule Proteins; D006801:Humans; D066298:In Vitro Techniques; D015847:Interleukin-4 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D014066:Palatine Tonsil / Q000166:cytology; D012260:Ribonucleases
D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D007378:Interleukins; D015847:Interleukin-4; D012260:Ribonucleases