Pk. Eplingburnette et al., EXPRESSION OF INTERLEUKIN-2 RECEPTOR-GAMMA ON HUMAN MONOCYTES - CHARACTERIZATION OF LINEAGE-SPECIFIC POSTTRANSLATIONAL MODIFICATIONS, European Journal of Immunology, 25(1), 1995, pp. 291-294
Functional interleukin-2 receptors (IL-2R) on lymphocytes contain both
IL-2R beta P and gamma chains. Whereas constitutive expression of IL-
2R beta has been found on monocytes, the expression of IL-2R gamma on
these phagocytes has not been examined. We performed reverse-transcrip
tion-polymerase chain reaction with Southern blot analysis on RNA deri
ved from purified human monocytes and discovered that they constitutiv
ely produce IL-2R gamma mRNA. Western immunoblotting revealed 58- and
64-kDa forms of IL-2R gamma on YT-1 and human monocytes, whereas 58-,
64-, and 69-kDa bands were detected using peripheral blood mononuclear
cells and non-adherent lymphocytes. These different forms resulted fr
om variable N-linked glycosylation since culture of the cells in tunic
amycin resulted in detection of a single 39-kDa band which corresponds
to the molecular weight predicted from the deduced amino acid sequenc
e. By co-immunoprecipitation, the IL-2R beta subunit associates with o
nly the 64-kDa IL-2R gamma protein band in monocytes.