IL-3 facilitates lymphocyte hexose transport by enhancing the intrinsic activity of the transport system.

Interleukin 3 (IL-3) promotes the survival and proliferation of hematopoietic cells of various lineages in culture. Like most other hematopoietic colony stimulating factors, its mode of action is unknown. However, binding of the lymphokine induces protein tyrosine phosphorylation and enhanced glucose transport in some myeloid progenitor cells. We have studied the hexose uptake following IL-3 stimulation in IL-3-dependent pro-B cells. IL-3 facilitated the uptake of 2-deoxyglucose within 15 min. Kinetic analysis of the 2-deoxyglucose uptake attributed the enhanced transport to improved transporter function, while other hormones or cytokines affect glucose transport primarily via the number of cell surface transporters.