Proliferation response to interleukin-2 and Jak/Stat activation of T cells immortalized by human T-cell lymphotropic virus type 1 is independent of open reading frame I expression.
Human T-cell lymphotropic virus type 1 (HTLV-1), a complex retrovirus, encodes a hydrophobic 12-kD protein from pX open reading frame (ORF) I that localizes to cellular endomembranes and contains four minimal SH3 binding motifs (PXXP). We have demonstrated the importance of ORF I expression in the establishment of infection and hypothesize that p12(I) has a role in T-cell activation. In this study, we tested interleukin-2 (IL-2) receptor expression, IL-2-mediated proliferation, and Jak/Stat activation in T-cell lines immortalized with either wild-type or ORF I mutant clones of HTLV-1. All cell lines exhibited typical patterns of T-cell markers and maintained mutation fidelity. No significant differences between cell lines were observed in IL-2 receptor chain (alpha, beta, or gamma(c)) expression, in IL-2-mediated proliferation, or in IL-2-induced phosphorylated forms of Stat3, Stat5, Jak1, or Jak3. The expression of ORF I is more likely to play a role in early HTLV-1 infection, such as in the activation of quiescent T cells in vivo.
Collins
N D
ND
Center for Retrovirus Research, Department of Veterinary Biosciences, The Arthur James Cancer Hospital, Columbus, Ohio 43210, USA.
D'Souza
C
C
Albrecht
B
B
Robek
M D
MD
Ratner
L
L
Ding
W
W
Green
P L
PL
Lairmore
M D
MD
D002461:Cell Line, Transformed; D002472:Cell Transformation, Viral; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D008213:Lymphocyte Activation; D016366:Open Reading Frames / Q000235:genetics; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*
D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D015534:Trans-Activators; D011505:Protein-Tyrosine Kinases