Time-dependent cytotoxic action of @entity1 recombinant alpha-interferon ( @entity14585 ) in vitro and the sensitivity of various cultured @entity1778 and XXXX cell lines to it.

@entity1 @entity1357 @entity981 @entity1619 @entity706 @entity5 @entity784 @entity1778 @entity9653 @entity4654 @entity14585
The growth inhibitory activity of @entity1 recombinant leucocyte A interferon ( @entity14585 : alpha-interferon) against 23 @entity1 cultured cell lines derived from @entity1778 and @entity706 was measured quantitatively by regrowth assay. Daudi cells were the most sensitive to it. Two T-cell lines ( @entity1 , HUT78), three B-cell lines (Raji, Ly16, A3/Kawakami), one @entity784 , non-B @entity981 ( @entity981 ) cell line (KOPN-1) and three myelomonocytoid cell lines (U937, @entity1357 , @entity4654 ) were moderately or slightly sensitive. Although the levels of sensitivity of these cell lines were different, cells could be killed by the recombinant alpha-interferon. Morphological changes in the sensitive cells treated with it were decreases in mitosis, pyknosis and fragmentation of the cells. Thirteen other cultured cell lines were not sensitive. The results indicated that the growth inhibitory activity of recombinant alpha-interferon is not always cell lineage-specific. There were only three cell lines whose sensitivity, expressed by the concentration required for 90% growth inhibition, was less than the several hundred units per milliliter that has usually been obtained as blood levels in clinical trials. These three included one of 10 T-cell lines and two of seven B-cell lines; none of six @entity784 , non-B @entity981 and myelomonocytoid cell lines were that sensitive. Among virus-associated cell lines, only @entity9653 -associated B-cell lines were sensitive to the interferon; adult @entity1619 virus-associated T-cell lines were not sensitive. It was demonstrated that recombinant alpha-interferon has a time-dependent, but not a concentration-dependent cytocidal action, indicating that optimal therapeutic schedules of recombinant alpha-interferon for @entity5 may be daily long-term treatment, not single or short-term large-dose therapy.
