Monocyte-derived human B-cell growth factor identified as interferon-beta 2 (BSF-2, IL-6).
Soluble products of either Epstein-Barr virus (EBV)-infected B cells or activated monocytes promote the proliferation of EBV-infected B cells and permit their growth at low cell densities. This suggests that growth factors are important for B-cell immortalization by EBV. In this study, a monocyte-derived factor that promotes the growth of EBV-infected b cells was purified and identified as interferon-beta 2 (IFN-beta 2), which is also known as 26-kilodalton protein, B-cell differentiation factor (BSF-2), and interleukin-6 (IL-6). The purified protein has a specific activity of approximately 4 X 10(7) units per milligram of protein in assays of B-cell growth. Thus, IFN-beta 2/BSF-2 is a B-cell growth factor that promotes the proliferation of human B cells infected with EBV.
Tosato
G
G
Division of Biochemistry and Biophysics, Food and Drug Administration, Bethesda, MD 20892.
Seamon
K B
KB
Goldman
N D
ND
Sehgal
P B
PB
May
L T
LT
Washington
G C
GC
Jones
K D
KD
Pike
S E
SE
D001402:B-Lymphocytes / Q000166:cytology* / Q000382:microbiology; D002452:Cell Count; D002455:Cell Division; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D007118:Immunoassay; D015850:Interleukin-6; D007378:Interleukins / Q000302:isolation & purification / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism*
D015850:Interleukin-6; D007378:Interleukins