Chemoattractant(s) in culture supernatants of HTLV-I-Infected T-cell lines.
Supernatants obtained from four HTLV-I transformed cell lines (MT2, MT4, C91/PL, and 81-66/45) induced in vitro migration of monocytes, polymorphonuclear leukocytes (PMN), and lymphocytes. The MT2, C91/PL, and 81-66/45 cell lines expressed both lymphotoxin (LT) and tumor necrosis factor (TNF-alpha) mRNA transcripts, and had TNF biological activity. In contrast, the MT4 cells did not express LT mRNA, had low levels of TNF-alpha transcript, and no TNF activity in the supernatant. Anti-TNF-alpha MAb, which blocks the chemotactic activity of recombinant TNF-alpha, had no inhibitory effect on the induction of migration by the MT2 and MT4 supernatants. Hence, no correlation was evident between TNF and chemotactic activity in supernatants of different HTLV-I-infected cell lines. Upon fractionation on Sephadex G50, the monocyte chemoattractant(s) eluted with two peaks in the 8-12 kD region, a size compatible with the chemotactic cytokines IL-8 and monocyte chemotactic protein (MCP). However, anti-IL-8 and anti-MCP antibodies did not have any effect, and Northern blot analysis showed that HTLV-I-transformed cell lines did not express mRNA transcripts of either IL-8 and MCP. These results demonstrate that HTLV-I transformed T-cell lines produce chemoattractant(s) active on PMN and monocytes, distinct from LT, TNF-alpha, IL-8, and MCP. Production of chemoattractants may play a role in the pathogenesis of diseases associated with HTLV-I infection.
Saggioro
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Istituto di Oncologia, Centro Interuniversitario per la Ricerca sul Cancro (C.I.R.C.), I.S.T., Padova, Italy.
Wang
J M
JM
Sironi
M
M
Luini
W
W
Mantovani
A
A
Chieco-Bianchi
L
L
D015152:Blotting, Northern; D002461:Cell Line, Transformed; D002630:Chemotactic Factors / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte; D002850:Chromatography, Gel; D015368:Human T-lymphotropic virus 1 / Q000502:physiology*; D006801:Humans; D012313:RNA / Q000032:analysis; D013601:T-Lymphocytes / Q000378:metabolism / Q000382:microbiology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014779:Virus Replication
D002630:Chemotactic Factors; D014409:Tumor Necrosis Factor-alpha; D012313:RNA