Purification and identification of a CD25 expression inhibitory protein from cell-free supernatants of chronically HIV-infected promonocytic cells.
The CD25 (IL-2-R alpha) cell surface glycoprotein expressed transiently during T-cell activation is implicated in the high affinity IL-2 receptor. This paper shows that cell-free supernatants from chronically HIV-infected promonocytic cells spontaneously produce a soluble factor which inhibits CD25 expression on PHA-activated human PBMC. We purified the CD25 expression inhibitory activity by a factor 12,350, using XM50 ultrafiltration, Superose 12 molecular sieving chromatography and MonoQ anion-exchange chromatography. Then we associated this activity to one single spot (M(r) 29,000, pI 6.8) on an O'Farrell two-dimensional gel. Our data demonstrate that this protein (M(r) 29,000, pI 6.8) is released from HIV-infected promonocytic cells and suggest that this factor is a new monokine regulating the T-cell activation process.
Célérier
J
J
Unité d'Oncogénèse Appliquée Institut National de la Santé et de la Recherche Médicale Unité 268, Hôpital Paul Brousse, Villejuif, France.
Cibert
C
C
Barré-Sinoussi
F
F
Ammar
A
A
Jasmin
C
C
D002460:Cell Line; D002474:Cell-Free System; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007526:Isoelectric Point; D008213:Lymphocyte Activation; D008970:Molecular Weight; D009000:Monocytes / Q000276:immunology* / Q000382:microbiology; D015846:Monokines / Q000737:chemistry / Q000302:isolation & purification* / Q000502:physiology; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D013601:T-Lymphocytes / Q000276:immunology*
D015846:Monokines; D015375:Receptors, Interleukin-2