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PubMed · 12943800

Native and recombinant interleukin-2, two functionally distinct molecules.

Maria C Denis·Brigitte T Huber
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Abstract

Recombinant IL-2 (rIL-2) produced in prokaryotes, is widely used in lieu of native IL-2, which is secreted by T cells, to assess the functional profile of this cytokine. We provide evidence that a naturally occurring species of post-translationally modified IL-2 (moIL-2) exhibits enhanced bioactivity compared to rIL-2, as tested at the biochemical and functional level. We show that moIL-2 has high binding affinity for the IL-2 receptor (IL-2R), induces the immediate expression of the IL-2R alpha chain and rapidly activates downstream signaling molecules. Finally, in contrast to rIL-2, moIL-2 can promote the antigen-independent proliferation of resting lymphocytes. Collectively, our data demonstrate that native moIL-2 is functionally distinct from rIL-2, suggesting the existence of diverse IL-2 variants which may be critical for the shaping of the immune response.

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Cell DivisionHumansInterleukin-2Recombinant ProteinsT-LymphocytesComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Maria C Denis, Brigitte T Huber. 2003. Native and recombinant interleukin-2, two functionally distinct molecules.. https://doi.org/10.1016/s0161-5890(03)00102-0

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