Native and recombinant interleukin-2, two functionally distinct molecules.
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.
Denis
Maria C
MC
Department of Pathology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA.
Huber
Brigitte T
BT
D002455:Cell Division / Q000502:physiology; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D013601:T-Lymphocytes / Q000502:physiology
D007376:Interleukin-2; D011994:Recombinant Proteins