Distinction between gamma c detection and function in YT lymphoid cells and in the granulocyte-macrophage colony-stimulating factor-responsive human myeloid cell line, Tf-1.
Peripheral blood monocytes respond to interleukin-2 (lL-2) and express the gamma common (gamma c) subunit of the lL-2 receptor (lL-2R) complex. However, the role of lL-2 in myeloid development has recently become of interest for several reasons, including the effect gamma c mutations may or may not have on myeloid development in patients with XSCID. Many studies of lL-2 function in the myeloid cell lineage have been performed on a murine background. To study gamma c expression and function in human myeloid precursors, we introduced the human myelomonocytic cell line, Tf-1, with a retroviral vector containing the human lL-2R beta subunit to create functional human intermediate lL-2R consisting of beta gamma c dimers. We have characterized this transfected variant of Tf-1 (Tf-1 beta) with regard to its response to lL-2. Unlike the parental Tf-1 cell line that is deficient in both lL-2R alpha and lL-2R beta expression, the Tf-1 beta transfectant binds and responds to lL-2 through intermediate-affinity lL-2Rs. Scatchard analyses indicate the number of intermediate-affinity receptors on Tf-1 beta is similar to the number found on the well-characterized YT cell line. However, detection of gamma c on Tf-1 beta cells is dramatically less than on YT cells by Western blot analysis and is undetectable by flow cytometric studies and surface iodinations. The gamma c component on YT cells is readily detected by all three methods. We conclude from these studies that the intermediate-affinity lL-2Rs on the Tf-1 cell line behave differently than those on YT cells with respect to gamma c detection. Either the gamma c molecule itself is different, or the cellular environment in which it functions is altered. Elucidation of gamma c function on this cell line will allow for its use as a model in which other cytokines using gamma c (including lL-2, lL-4, and lL-15) can be studied on the same cellular background.
Farner
N L
NL
Department of Human Oncology, University of Wisconsin, Madison 53792, USA.
Voss
S D
SD
Leary
T P
TP
Gan
J
J
Hakimi
J
J
Evans
G
G
Ju
G
G
Sondel
P M
PM
D000818:Animals; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004303:Dosage Compensation, Genetic; D015672:Erythroid Precursor Cells / Q000187:drug effects*; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D007700:Kinetics; D004915:Leukemia, Erythroblastic, Acute / Q000473:pathology*; D008223:Lymphoma / Q000473:pathology; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D011487:Protein Conformation; D015375:Receptors, Interleukin-2 / Q000032:analysis / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000378:metabolism; D016511:Severe Combined Immunodeficiency / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D013329:Structure-Activity Relationship; D013953:Thymus Neoplasms / Q000473:pathology; D014162:Transfection; D014407:Tumor Cells, Cultured; D014960:X Chromosome
D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D011993:Recombinant Fusion Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor