TY - JOUR
T1 - A p74 common gamma receptor chain isoform facilitates IL-2 and IL-15 responses by the myelomonocytic cell line Tf-1β2
AU - Monson, Nancy L.
AU - Fenske, Timothy J.
AU - Wei, Shyng
AU - Okragly, Angela J.
AU - De Jong, Jill L O
AU - Haak-Frendscho, Mary
AU - O'Shea, John
AU - Djeu, Julie
AU - Sondel, Paul M.
PY - 2001
Y1 - 2001
N2 - Functional forms of the IL-2, IL-4, IL-7, IL-9, and IL-15 receptors require the γc receptor component. We have described previously a myeloid cell line called Tf-1β, which binds IL-2 with intermediate-affinity and proliferates in response to IL-2. In this study, we characterize γc expression on Tf-1β2 cells, a derivative of Tf-1β cells stimulated exclusively with IL-2. Although Tf-1β2 cells bind IL-2 with intermediate-affinity and proliferate in response to IL-2, this cell line does not express the p64 γc chain at the protein level. This result was surprising because prior studies suggest these cells should not be expected to proliferate in response to IL-2 or IL-15 in the absence of the p64 γc chain. A p74 protein was detected by western blot following immunoprecipitation with an anti-γc polyclonal antibody, and a p74 protein was identified consistently in complex with IL-2 and IL-15 on these cells. However, the γc gene in these Tf-1β2 cells shows no evidence of mutation by sequence analysis. Furthermore, inhibition of glycosylation of these Tf-1β2 cells by tunicamycin treatment yields a standard 39-kDa molecule recognized on western blot with anti-γc antibody, as seen for the standard 64-kDa isoform of γc. These results demonstrate that a 74-kDa γc receptor isoform was involved in the response of the Tf-1β2 cells to cytokines which normally interact with the 64-kDa γc chain.
AB - Functional forms of the IL-2, IL-4, IL-7, IL-9, and IL-15 receptors require the γc receptor component. We have described previously a myeloid cell line called Tf-1β, which binds IL-2 with intermediate-affinity and proliferates in response to IL-2. In this study, we characterize γc expression on Tf-1β2 cells, a derivative of Tf-1β cells stimulated exclusively with IL-2. Although Tf-1β2 cells bind IL-2 with intermediate-affinity and proliferate in response to IL-2, this cell line does not express the p64 γc chain at the protein level. This result was surprising because prior studies suggest these cells should not be expected to proliferate in response to IL-2 or IL-15 in the absence of the p64 γc chain. A p74 protein was detected by western blot following immunoprecipitation with an anti-γc polyclonal antibody, and a p74 protein was identified consistently in complex with IL-2 and IL-15 on these cells. However, the γc gene in these Tf-1β2 cells shows no evidence of mutation by sequence analysis. Furthermore, inhibition of glycosylation of these Tf-1β2 cells by tunicamycin treatment yields a standard 39-kDa molecule recognized on western blot with anti-γc antibody, as seen for the standard 64-kDa isoform of γc. These results demonstrate that a 74-kDa γc receptor isoform was involved in the response of the Tf-1β2 cells to cytokines which normally interact with the 64-kDa γc chain.
KW - Cytokine receptors
KW - Cytokines
KW - Monocytes
KW - Signaling
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M3 - Article
C2 - 11261789
AN - SCOPUS:0035103807
SN - 0741-5400
VL - 69
SP - 419
EP - 425
JO - Journal of Leukocyte Biology
JF - Journal of Leukocyte Biology
IS - 3
ER -