Leukemic cells in hairy cell leukemia and B cell chronic lymphocytic leukemia release soluble TNF receptors.
The two tumor necrosis factor receptors (TNF-Rs) exist in their soluble form in different biological fluids. In this study we investigated the concentrations of soluble tumor necrosis factor receptors (sTNF-Rs) in the culture supernatants of leukemic cells and in the serum obtained from 33 patients: 12 with hairy cell leukemia (HCL) and 21 with B cell chronic lymphocytic leukemia (B-CLL). In seven patients with HCL, sTNF-Rs were also evaluated following in vivo treatment with interferon-alpha (IFN-alpha). Purified leukemic cells from patients with HCL and B-CLL spontaneously released sTNF-R75 but not sTNF-R55. The levels of sTNF-R75 were higher in supernatants obtained from cultured hairy cells than from cultures of B-CLL cells. The shedding of sTNF-R75 was further increased both in HCL and B-CLL subjects by some B cell-related stimuli, including BCGF, PMA, SAC and was partially inhibited by IFN-alpha in patients with HCL. Sera from HCL patients presented increased levels of both sTNF-Rs with respect to normal controls. Treatment of HCL patients with IFN-alpha resulted in a decrease in serum levels of sTNF-Rs, particularly sTNF-R75. These findings suggest that leukemic cells account for the increased serum levels of sTNF-R75 observed in patients with HCL and B-CLL, but not for sTNF-R55.
Trentin
L
L
Department of Clinical Medicine, Padua University School of Medicine, Italy.
Pizzolo
G
G
Zambello
R
R
Agostini
C
C
Morosato
L
L
Sancetta
R
R
Adami
F
F
Vinante
F
F
Chilosi
M
M
Gallati
H
H
D015703:Antigens, CD / Q000032:analysis; D006801:Humans; D016898:Interferon-alpha / Q000627:therapeutic use*; D007943:Leukemia, Hairy Cell / Q000097:blood / Q000276:immunology* / Q000628:therapy; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood / Q000276:immunology* / Q000628:therapy; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis*; D014407:Tumor Cells, Cultured
D015703:Antigens, CD; D016898:Interferon-alpha; D018124:Receptors, Tumor Necrosis Factor