Human T‐Lymphoblastoid Cell Lines with High and Low Abilities to Produce Interferon‐Gamma Constitutively and Their Susceptibilities to Interferon

A human T‐lymphoblastoid cell line, TCL‐Fuj, produces large amounts of interferon (IFN)‐ γ constitutively. A variant cell line, 2M, was derived from it. Both cell lines express similar surface antigen markers, but differ in surface morphology. Compared with the parent TCL‐Fuj cell line, 2M produced less IFN‐ γ constitutively but more in response to IFN inducers. The IFNs produced constitutively and on stimulation with inducers were analyzed by SDS‐polyacrylamide gel electrophoresis. In TCL‐Fuj cells, the constitutive and induced IFNs consisted of the same molecular species (22K and 39K). In 2M cells, smaller IFNs were produced constitutively (18K and 32K) and induction resulted in a marked increase of 22K molecules. These two cell lines also differed in sensitivity to the antiviral activity of IFN. Other T‐lymphoblastoid cell lines, HPB‐ALL and TCL‐Fuj 4 cells, which did not produce IFN‐ γ were permissive for vesicular stomatitis virus (VSV) replication; its growth was markedly suppressed by IFN‐ γ and ‐ α . TCL‐Fuj cells were also permissive for VSV, but were not susceptible to the antiviral effect of the IFNs. In contrast, in 2M cells the multiplication of VSV was restricted; the viral yield was further reduced by the IFNs and increased by treatment with anti‐human IFN‐ γ serum. Several clonal cell lines derived from TCL‐Fuj and 2M cells had characteristics similar to the respective parent cell lines. The growth of both cell lines was not affected by IFN‐ γ or by ‐ α . The separation of antiviral and anti‐proliferative susceptibilities was peculiar to 2M cells unlike other cell lines.