title: Relative cloning efficiencies and long-term propagation capacity for T cell clones of highly purified natural interleukin 2 compared to recombinant interleukin 2 in man.
abstract: Highly purified (HP) natural (n) and recombinant (r) interleukin 2 (IL 2) have been compared for their ability to support clonal outgrowth and long-term clonal propagation of alloactivated human T lymphocytes. The frequency of outgrowth of T cell colonies was as high as 1:2 to 1:4 when HPnIL 2 was employed for limiting dilution cloning. Separated CD4+ and CD8+ activated populations produced similar cloning efficiencies. Recloning of established CD4+ lines in HPnIL 2 suggested that a clonable cell frequency of 1:2-1:4 was the maximum possible that could be achieved in this system. In contrast, purified rIL 2 allowed outgrowth of only 1:10-1:20 cells from alloactivated populations. Again, CD4+ and CD8+ fractions generated similar cloning efficiencies. In terms of the fraction of derived clones, which could be propagated to greater than 1 X 10(6) and greater than 1 X 10(8) cells, nIL 2 again proved superior to rIL 2. In either source of IL 2, the proportion of CD4+ clones which could be extensively propagated was greater than in the CD8+ population. Surprisingly, although the addition of PHA to these lectin-free IL 2 preparations reduced the frequency of clonable cells, the proportion of clones which could be extensively propagated was increased. These results suggest that nIL 2, consisting of three differently glycosylated molecular species, may be preferable to rIL 2, which consists only of a single non-glycosylated species, for the cloning and long-term propagation of human T cells. These results may have some bearing on the choice of rIL 2 versus nIL 2 for therapeutic applications.
mesh_terms: D002455:Cell Division / Q000187:drug effects; D002469:Cell Separation; D002470:Cell Survival; D002999:Clone Cells / Q000166:cytology / Q000187:drug effects; D003114:Colony-Forming Units Assay; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013601:T-Lymphocytes / Q000166:cytology* / Q000187:drug effects; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000187:drug effects; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects
chemical_list: D007376:Interleukin-2; D010835:Phytohemagglutinins; D011994:Recombinant Proteins