Spontaneous Production of High Levels of Leukocyte ( ) Interferon by a Human Lymphoblastoid B-Cell Line (LDV/7)

Abstract

A human lymphoblastoid B-cell line (LDV/7) capable of replicating significant levels of transfer factor and immune RNA was found to produce high quantities of interferon continuously. The maximum yield of interferon (600 units/ml) was detected on the seventh day. The interferon was characterized as human leukocyte (a) type. This interferon exhibited broad antiviral activity against vesicular stomatitis virus, poliovirus, sindbis virus, Herpesvirus saimiri, and Epstein-Barr virus. Treatment of LDV/7 cells with TPA, PHA, or LPS failed to enhance interferon production. Furthermore, LDV/7 cells could not be induced with Sendai virus to produce larger amounts of interferon. Interferon production correlated best with cell proliferation. It is therefore possible that this cell line may be a good source for large-scale production of human leukocyte interferon as well as for cloning of the interferon genome, and for studies of gene expression.114 0037-9727/82/090 1

Interferon alpha induces the expression of retinoblastoma gene product in human Burkitt lymphoma Daudi cells: role in growth regulation.

“…Recently IFNs have been considered to also have a negative regulatory role in the autocrine regulation of cell proliferation, as several growth factors induce the formation ofIFN in the cells they stimulate (4)(5)(6). In addition, IFN-a and IFN-/3 are also constitutively expressed in cells derived from the hematopoietic system: in lymphoblastoid cells, in leukemic and normal peripheral leukocytes, and in macrophage cultures (7,8).…”

“…Induced expression of 2-5(A) synthetase by IFNs appears to play an important role in some cell types (3) but not in Burkitt lymphoma Daudi cells. 2-5(A) synthetase and other IFNinduced genes, such as 561, MTII, and 2A, are induced well by IFN-a in growth-sensitive and growth-resistant Daudi cells (10)(11)(12)(13), whereas some other genes, such as 1-8, 9-27, and [6][7][8][9][10][11][12][13][14][15][16], are induced only in growth-sensitive Daudi cells (13). Another suggested mechanism of phenotypical reversion of transformed cells by IFNs could involve modulation of expression of the oncogenes in target cells (14).…”