Human IgE mRNA expression by peripheral blood lymphocytes stimulated with interleukin 4 and pokeweed mitogen.
Expression of human IgE mRNA by peripheral blood lymphocytes (PBL) and an IgE-producing myeloma cell line, U-266, was examined by Northern blot hybridization and compared with IgE levels in culture supernatants. A 2.35-kb IgE mRNA was detected in unstimulated atopic PBL and U-266 cells but not in normal PBL, and its levels correlated with IgE protein levels in the supernatant. Upon stimulation with interleukin 4, a new 1.75-kb transcript was revealed in both atopic and normal PBL but not in U-266 cells. Its expression did not correlate with IgE levels in the supernatant. Pokeweed mitogen also induced the expression of the 1.75-kb transcript without concomitant induction of IgE synthesis by normal PBL and even suppressed the spontaneous expression of the 2.35-kb transcript and IgE protein synthesis by atopic PBL. Interferon-gamma, which suppressed both the 2.35-kb transcript and IgE protein production, had no inhibitory effect on the 1.75-kb transcript. Expression of the 1.75-kb transcript was already high after 2 days of stimulation and peaked around day 4. The length of the transcript is smaller than that of mRNA coding for secreted human IgG and IgA and contains all four C epsilon exon sequences, suggesting it might be a truncated transcript without v region and might be a human counterpart of the murine germ-line C epsilon transcript.
Qiu
G
G
Institute of Clinical Immunology, Inselspital, University of Bern, Switzerland.
Gauchat
J F
JF
Vogel
M
M
Mandallaz
M
M
De Weck
A L
AL
Stadler
B M
BM
D015152:Blotting, Northern; D002478:Cells, Cultured; D006801:Humans; D007073:Immunoglobulin E / Q000096:biosynthesis* / Q000235:genetics; D007371:Interferon-gamma / Q000502:physiology; D015847:Interleukin-4 / Q000502:physiology*; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D011043:Pokeweed Mitogens / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis*; D011994:Recombinant Proteins; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D011043:Pokeweed Mitogens; D012333:RNA, Messenger; D011994:Recombinant Proteins; D015847:Interleukin-4; D007073:Immunoglobulin E; D007371:Interferon-gamma; D015719:Single-Strand Specific DNA and RNA Endonucleases