Signal transduction by IgG receptors induces calcium mobilization, but not histamine release, in the human basophilic cell line KU812F.
Human blood basophils selectively express Fc gamma RII (CDw32) among IgG receptor subtypes, but its functional role in allergic reactions remains unknown. Using the human basophilic leukemia cell line KU812F as a model system, we investigated cellular signaling events mediated through IgG receptor stimulation. KU812F cells express Fc gamma RII on their surface. mRNAs for both Fc gamma RIIA and IIB subtypes were detected by reverse transcriptase-PCR analysis. In this cell line, Fc gamma RII stimulation induced mobilization of free intracellular calcium and actin polymerization. Yet, no significant histamine release was observed, nor did blood basophils stimulated by anti-Fc gamma RII monoclonal antibody IV.3 and by a secondary antibody release histamine. These data indicate that Fc gamma RII stimulation induces cellular signaling events such as calcium mobilization in human basophils. However, these events do not lead to histamine release.
Kawata
N
N
Department of Medicine II, Okayama University Medical School, Japan.
Takata
M
M
Suwaki
T
T
Tanimoto
Y
Y
Soda
R
R
Takahashi
K
K
Kimura
I
I
D000199:Actins / Q000378:metabolism; D001483:Base Sequence; D001491:Basophils / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D017931:DNA Primers / Q000737:chemistry; D004587:Electrophoresis, Agar Gel; D006636:Histamine Release; D006801:Humans; D016130:Immunophenotyping; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000378:metabolism; D015345:Oligonucleotide Probes / Q000737:chemistry; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D017452:Receptors, IgG / Q000502:physiology*; D015398:Signal Transduction
D000199:Actins; D017931:DNA Primers; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D017452:Receptors, IgG; D002118:Calcium