Synthesis of human interferon by Xenopus laevis oocytes: two structural genes for interferons in human cells.

Abstract

Human fibroblasts and leukocytes produce interferons which may be distinguished by their antigenic and species specificity as well as by their molecular weight distributions. To elucidate the basis or these differences, we isolated mRNA from induced human fibroblasts and lymphoblastoid (Namalva) cells and studied the products of translation in Xenopus Iaevis oocytes. The mRNA from the respective cells yielded translation products, in oocytes, that were characteristic of the cells from which the mRNA was derived. We conclude that human cells contain at least two structural genes for interferon, coding for polypeptides differing in primary sequence. Fibroblasts synthesize a single species of interferon; Iymphoblastoid cells synthesize two species, the fibroblast and leukocyte types.

Characteristics of Human Lymphoblastoid (Namalva) Interferon

“…We concluded that two separate structural genes are likely to exist for these two antigenic species of human interferon (Cavalieri et al 1977). These earlier results and the present data suggest that both interferon genes are expressed during the induction of Namalva cells.…”

“…Preliminary investigations carried out in this laboratory revealed that Namalva interferon is not completely neutralized by either specific antileukocyte or anti-fibroblast interferon sera; however, a mixture of the anti-leukocyte and anti-fibroblast interferon sera did cause complete neutralization of the antiviral activity of Namalva interferon (Cavalieri et al 1977).…”

Construction and identification of bacterial plasmids containing nucleotide sequence for human leukocyte interferon.

“…They differ biologically, chemically, and physically. In addition, it has been shown that leukocyte and fibroblast interferons are products of different structural genes (6). Although a great deal of research has been directed toward an understanding of the molecular mechanism of interferon induction and activity, progress has been slow due largely to the small amounts of pure interferon protein and mRNA for study.…”

Cell Cultures Producing Human Interferon

“…Although there are many lymphoblast cell lines that grow readily in culture (8,13), only the Burkitt's lymphoma-derived Namalva cell line has been shown to produce amounts of interferon substantial enough to warrant its use in large-scale production (9,18). Namalva cells yield both human leukocyte and human fibroblast interferon (2,5). In this report, we summarize the results of screening human B-lymphoblast and other leukocyte-derived cell lines for interferon production.…”