Constitutive IL-2 expression in HTLV-I-infected leukaemic T cell lines.
An IL-2 autocrine growth circuit has been proposed as a major mechanism in HTLV-I-related leukaemogenesis. We have developed a polymerase chain reaction combined with reverse transcription RT-PCR to detect IL-2 transcripts and a sensitive immunostaining method for IL-2 protein. Combination of these two methods with in situ hybridization demonstrated that most cells of the T cell line IARC 301.5, whose proliferation is stimulated by autocrine IL-2, constitutively synthesize IL-2. This pattern was also found in the HTLV-I T cell lines HUT, MT2 and C 8166/45, and in the HTLV-I-negative T cell lines Jurkat and HSB2 but not MOLT4. Four non-lymphoid cell lines and cultured fibroblasts were negative, in agreement with the T cell specificity of IL-2 synthesis. Hence, most T cell lines tested, whether HTLV-I-infected or not, constitutively synthesize IL-2, suggesting a possible common feature of leukaemic T cell lines. The presence of IL-2 transcript and protein in most cells of the reacting cell lines is consistent with an autocrine process possibly involved at some stage in acquiring growth autonomy.
Farcet
J P
JP
INSERM U.91, Hôpital Henri Mondor, Paris, France.
Lebargy
F
F
Lavignac
C
C
Gaulard
P
P
Dautry
A
A
Gazzolo
L
L
Roméo
P H
PH
Vainchenker
W
W
D000911:Antibodies, Monoclonal; D001483:Base Sequence; D006801:Humans; D007376:Interleukin-2 / Q000032:analysis / Q000235:genetics*; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000276:immunology*; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D012194:RNA-Directed DNA Polymerase / Q000235:genetics; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D012333:RNA, Messenger; D012194:RNA-Directed DNA Polymerase