Demonstration of two distinct forms of released low affinity-type rat IL-2 receptors.
The release of IL-2 binding proteins, derived from the 55,000 MW low affinity IL-2R (L chain), has been observed for virtually all L chain-bearing cells in either humans, the mouse or the rat. Based on the characterization of the released human L chain as a molecule 10,000 MW smaller than the cell surface receptor, either proteolytic cleavage or differential splicing of the L chain encoding mRNA have been suggested as mechanisms underlying the receptor release. Combining affinity labelling of the L chain with [125I]IL-2 and immunoprecipitation with L chain-specific monoclonal antibody (mAb) applied for the detection of soluble rat IL-2R revealed the existence of two classes of soluble receptors, one being of the same size as cell surface-expressed L chain, the other of 40,000 apparent molecular mass. These findings raise the possibility of other mechanisms of receptor release than those discussed for human L chain.
Herrmann
T
T
Institut für Immunologie, Freie Universität Berlin, FRG.
Josimovic-Alasevic
O
O
Mouzaki
A
A
Diamantstein
T
T
D000345:Affinity Labels; D000818:Animals; D002478:Cells, Cultured; D008970:Molecular Weight; D051381:Rats; D015375:Receptors, Interleukin-2 / Q000302:isolation & purification*; D012995:Solubility; D013601:T-Lymphocytes / Q000032:analysis
D000345:Affinity Labels; D015375:Receptors, Interleukin-2