Interlinking interleukin-7

Cytokine

Volumn 39, Issue 1, 2007, Pages 75-83

  Kittipatarin, Christina ^a   Khaled, Annette R ^a  

^a UNIVERSITY OF CENTRAL FLORIDA   (United States)

Author keywords

Cytokine; Homeostasis; Lymphocytes; Metabolism; Proliferation

Indexed keywords

CYCLIN DEPENDENT KINASE INHIBITOR 1B; CYTOKINE RECEPTOR; GLUCOSE TRANSPORTER 1; INTERLEUKIN 7; PHOSPHATIDYLINOSITOL 3 KINASE; PROTEIN KINASE B; PROTEIN TYROSINE PHOSPHATASE; STAT5 PROTEIN;

APOPTOSIS; CELL CYCLE PROGRESSION; CELL METABOLISM; CELL PROLIFERATION; CELL SURVIVAL; CYTOKINE PRODUCTION; GENE EXPRESSION; HOMEOSTASIS; HUMAN; LYMPHOCYTE PROLIFERATION; NONHUMAN; PRIORITY JOURNAL; REVIEW; SIGNAL TRANSDUCTION; T LYMPHOCYTE;

1-PHOSPHATIDYLINOSITOL 3-KINASE; ANIMALS; CDC25 PHOSPHATASES; CELL CYCLE; CELL PROLIFERATION; CELL SIZE; CYCLIN-DEPENDENT KINASE INHIBITOR P27; GLUCOSE TRANSPORTER TYPE 1; HUMANS; INTERLEUKIN-7; JANUS KINASES; PROTO-ONCOGENE PROTEINS C-AKT; RECEPTORS, INTERLEUKIN-7; SIGNAL TRANSDUCTION; STAT TRANSCRIPTION FACTORS; T-LYMPHOCYTES;

EID: 34548833894     PISSN: 10434666     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.cyto.2007.07.183     Document Type: Review

References (101)

1. Abraham N., Ma M.C., Snow J.W., Miners M.J., Herndier B.G., and Goldsmith M.A. Haploinsufficiency identifies STAT5 as a modifier of IL-7-induced lymphomas. Oncogene 24 (2005) 5252-5257
2. Barata J.T., Cardoso A.A., and Boussiotis V.A. Interleukin-7 in T-cell acute lymphoblastic leukemia: an extrinsic factor supporting leukemogenesis?. Leuk Lymphoma 46 (2005) 483-495
3. Barata J.T., Cardoso A.A., Nadler L.M., and Boussiotis V.A. Interleukin-7 promotes survival and cell cycle progression of T-cell acute lymphoblastic leukemia cells by down-regulating the cyclin-dependent kinase inhibitor p27(kip1). Blood 98 (2001) 1524-1531
4. Barata J.T., Silva A., Brandao J.G., Nadler L.M., Cardoso A.A., and Boussiotis V.A. Activation of PI3K is indispensable for interleukin 7-mediated viability, proliferation, glucose use, and growth of T cell acute lymphoblastic leukemia cells. J Exp Med 200 (2004) 659-669
5. Barthel A., Okino S.T., Liao J., Nakatani K., Li J., Whitlock Jr. J.P., et al. Regulation of GLUT1 gene transcription by the serine/threonine kinase Akt1. J Biol Chem 274 (1999) 20281-20286
6. Bentley J., Itchayanan D., Barnes K., McIntosh E., Tang X., Downes C.P., et al. Interleukin-3-mediated cell survival signals include phosphatidylinositol 3-kinase-dependent translocation of the glucose transporter GLUT1 to the cell surface. J Biol Chem. 278 (2003) 39337-39348
7. Beq S., Nugeyre M.T., Ho Tsong F.R., Gautier D., Legrand R., Schmitt N., et al. IL-7 induces immunological improvement in SIV-infected rhesus macaques under antiviral therapy. J Immunol 176 (2006) 914-922
8. Bernardi R., Liebermann D.A., and Hoffman B. Cdc25A stability is controlled by the ubiquitin-proteasome pathway during cell cycle progression and terminal differentiation. Oncogene 19 (2000) 2447-2454
9. Berry L.D., and Gould K.L. Regulation of Cdc2 activity by phosphorylation at T14/Y15. Prog Cell Cycle Res 2 (1996) 99-105
10. Blomberg I., and Hoffmann I. Ectopic expression of Cdc25A accelerates the G(1)/S transition and leads to premature activation of cyclin E- and cyclin A-dependent kinases. Mol Cell Biol 19 (1999) 6183-6194
11. Carr J.M., Carrasco M.J., Thaventhiran J.E., Bambrough P.J., Kraman M., Edwards A.D., et al. CD27 mediates interleukin-2-independent clonal expansion of the CD8+ T cell without effector differentiation. Proc Natl Acad Sci USA 103 (2006) 19454-19459
12. Cassese G., Parretta E., Pisapia L., Santoni A., Guardiola J., and Di Rosa F. Bone marrow CD8 cells down-modulate membrane IL-7R{alpha} expression and exhibit increased STAT-5 and p38 MAPK phosphorylation in the organ environment. Blood (2007)
13. Chakrabarti R., Jung C.Y., Lee T.P., Liu H., and Mookerjee B.K. Changes in glucose transport and transporter isoforms during the activation of human peripheral blood lymphocytes by phytohemagglutinin. J Immunol 152 (1994) 2660-2668
14. Cipres A., Carrasco S., and Merida I. Deletion of the acidic-rich domain of the IL-2Rbeta chain increases receptor-associated PI3K activity. FEBS Lett 500 (2001) 99-104
15. Conlon I.J., Dunn G.A., Mudge A.W., and Raff M.C. Extracellular control of cell size. Nat Cell Biol 3 (2001) 918-921
16. Coqueret O. New roles for p21 and p27 cell-cycle inhibitors: a function for each cell compartment?. Trends Cell Biol 13 (2003) 65-70
17. Crawley J.B., Rawlinson L., Lali F.V., Page T.H., Saklatvala J., and Foxwell B.M. T cell proliferation in response to interleukins 2 and 7 requires p38MAP kinase activation. J Biol Chem 272 (1997) 15023-15027
18. Crawley J.B., Willcocks J., and Foxwell B.M. Interleukin-7 induces T cell proliferation in the absence of Erk/MAP kinase activity. Eur J Immunol 26 (1996) 2717-2723
19. Datta S.R., Dudek H., Tao X., Masters S., Fu H., Gotoh Y., et al. Akt phosphorylation of BAD couples survival signals to the cell-intrinsic death machinery. Cell 91 (1997) 231-241
20. De Vito P. The sodium/hydrogen exchanger: a possible mediator of immunity. Cell Immunol 240 (2006) 69-85
21. Di Cristofano A., and Pandolfi P.P. The multiple roles of PTEN in tumor suppression. Cell 100 (2000) 387-390
22. Dumon S., Santos S.C., Debierre-Grockiego F., Gouilleux-Gruart V., Cocault L., Boucheron C., et al. IL-3 dependent regulation of Bcl-xL gene expression by STAT5 in a bone marrow derived cell line. Oncogene 18 (1999) 4191-4199
23. Ferguson A.M., White L.S., Donovan P.J., and Piwnica-Worms H. Normal cell cycle and checkpoint responses in mice and cells lacking Cdc25B and Cdc25C protein phosphatases. Mol Cell Biol 25 (2005) 2853-2860
24. Franchimont D., Galon J., Vacchio M.S., Fan S., Visconti R., Frucht D.M., et al. Positive effects of glucocorticoids on T cell function by up-regulation of IL-7 receptor alpha. J Immunol 168 (2002) 2212-2218
25. Fujita N., Sato S., Katayama K., and Tsuruo T. Akt-dependent phosphorylation of p27Kip1 promotes binding to 14-3-3 and cytoplasmic localization. J Biol Chem 277 (2002) 28706-28713
26. Garcia Z., Silio V., Marques M., Cortes I., Kumar A., Hernandez C., et al. A PI3K activity-independent function of p85 regulatory subunit in control of mammalian cytokinesis. EMBO J 25 (2006) 4740-4751
27. Garcia-Peydro M., de Yebenes V.G., and Toribio M.L. Notch1 and IL-7 receptor interplay maintains proliferation of human thymic progenitors while suppressing non-T cell fates. J Immunol 177 (2006) 3711-3720
28. Geiselhart L.A., Humphries C.A., Gregorio T.A., Mou S., Subleski J., and Komschlies K.L. IL-7 administration alters the CD4:CD8 ratio, increases T cell numbers, and increases T cell function in the absence of activation. J Immunol 166 (2001) 3019-3027
29. Goloudina A., Yamaguchi H., Chervyakova D.B., Appella E., Fornace Jr. A.J., and Bulavin D.V. Regulation of Human Cdc25A Stability by Serine 75 Phosphorylation Is Not Sufficient to Activate a S Phase Checkpoint. Cell Cycle 2 (2003) 473-478
30. Greiner E.F., Guppy M., and Brand K. Glucose is essential for proliferation and the glycolytic enzyme induction that provokes a transition to glycolytic energy production. J Biol Chem 269 (1994) 31484-31490
31. Grimmler M., Wang Y., Mund T., Cilensek Z., Keidel E.M., Waddell M.B., et al. Cdk-inhibitory activity and stability of p27Kip1 are directly regulated by oncogenic tyrosine kinases. Cell 128 (2007) 269-280
32. Hassepass I., Voit R., and Hoffmann I. Phosphorylation at serine 75 is required for UV-mediated degradation of human Cdc25A phosphatase at the S-phase checkpoint. J Biol Chem 278 (2003) 29824-29829
33. Jiang Q., Li W.Q., Aiello F.B., Mazzucchelli R., Asefa B., Khaled A.R., et al. Cell biology of IL-7, a key lymphotrophin. Cytokine Growth Factor Rev 16 (2005) 513-533
34. Jiang Q., Li W.Q., Hofmeister R.R., Young H.A., Hodge D.R., Keller J.R., et al. Distinct regions of the interleukin-7 receptor regulate different Bcl2 family members. Mol Cell Biol 24 (2004) 6501-6513
35. Jinno S., Suto K., Nagata A., Igarashi M., Kanaoka Y., Nojima H., et al. Cdc25A is a novel phosphatase functioning early in the cell cycle. EMBO J 13 (1994) 1549-1556
36. Johnston G.C., Pringle J.R., and Hartwell L.H. Coordination of growth with cell division in the yeast Saccharomyces cerevisiae. Exp Cell Res 105 (1977) 79-98
37. Kaech S.M., Tan J.T., Wherry E.J., Konieczny B.T., Surh C.D., and Ahmed R. Selective expression of the interleukin 7 receptor identifies effector CD8 T cells that give rise to long-lived memory cells. Nat Immunol 4 (2003) 1191-1198
38. Kaldis P. Another piece of the p27Kip1 puzzle. Cell 128 (2007) 241-244
39. Khaled A.R., Bulavin D.V., Kittipatarin C., Li W.Q., Alvarez M., Kim K., et al. Cytokine-driven cell cycling is mediated through Cdc25A. J Cell Biol 169 (2005) 755-763
40. Khaled A.R., and Durum S.K. Death and Baxes: mechanisms of lymphotrophic cytokines. Immunol Rev 193 (2003) 48-57
41. Khaled A.R., Li W.Q., Huang J., Fry T.J., Khaled A.S., Mackall C.L., et al. Bax deficiency partially corrects IL-7 receptor alpha deficiency. Immunity 17 (2002) 561-573
42. Khaled A.R., Moor A.N., Li A., Kim K., Ferris D.K., Muegge K., et al. Trophic factor withdrawal: p38 mitogen-activated protein kinase activates NHE1, which induces intracellular alkalinization. Mol Cell Biol 21 (2001) 7545-7557
43. Kim K., Khaled A.R., Reynolds D., Young H.A., Lee C.K., and Durum S.K. Characterization of an interleukin-7-dependent thymic cell line derived from a p53(-/-) mouse. J Immunol Methods 274 (2003) 177-184
44. Kittipatarin C., Li W.Q., Bulavin D.V., Durum S.K., and Khaled A.R. Cell cycling through Cdc25A: transducer of cytokine proliferative signals. Cell Cycle (2006) 5
45. Komschlies K.L., Gregorio T.A., Gruys M.E., Back T.C., Faltynek C.R., and Wiltrout R.H. Administration of recombinant human IL-7 to mice alters the composition of B-lineage cells and T cell subsets, enhances T cell function, and induces regression of established metastases. J Immunol 152 (1994) 5776-5784
46. Kovanen P.E., and Leonard W.J. Cytokines and immunodeficiency diseases: critical roles of the gamma(c)-dependent cytokines interleukins 2, 4, 7, 9, 15, and 21, and their signaling pathways. Immunol Rev 202 (2004) 67-83
47. Lali F.V., Crawley J., McCulloch D.A., and Foxwell B.M. A late, prolonged activation of the phosphatidylinositol 3-kinase pathway is required for T cell proliferation. J Immunol 172 (2004) 3527-3534
48. Leonard W.J. Role of Jak kinases and STATs in cytokine signal transduction. Int J Hematol 73 (2001) 271-277
49. Li W.Q., Jiang Q., Aleem E., Kaldis P., Khaled A.R., and Durum S.K. IL-7 promotes T cell proliferation through destabilization of p27Kip1. J Exp Med 203 (2006) 573-582
50. Li W.Q., Jiang Q., Khaled A.R., Keller J.R., and Durum S.K. Interleukin-7 inactivates the pro-apoptotic protein bad promoting T cell survival. J Biol Chem 279 (2004) 29160-29166
51. Lum J.J., Bauer D.E., Kong M., Harris M.H., Li C., Lindsten T., et al. Growth factor regulation of autophagy and cell survival in the absence of apoptosis. Cell 120 (2005) 237-248
52. Maddika S., Ande S.R., Panigrahi S., Paranjothy T., Weglarczyk K., Zuse A., et al. Cell survival, cell death and cell cycle pathways are interconnected: implications for cancer therapy. Drug Resist Updat 10 (2007) 13-29
53. Mailand N., Podtelejnikov A.V., Groth A., Mann M., Bartek J., and Lukas J. Regulation of G(2)/M events by Cdc25A through phosphorylation-dependent modulation of its stability. EMBO J 21 (2002) 5911-5920
54. Manel N., Kim F.J., Kinet S., Taylor N., Sitbon M., and Battini J.L. The ubiquitous glucose transporter GLUT-1 is a receptor for HTLV. Cell 115 (2003) 449-459
55. Manel N., Kinet S., Battini J.L., Kim F.J., Taylor N., and Sitbon M. The HTLV receptor is an early T-cell activation marker whose expression requires de novo protein synthesis. Blood 101 (2003) 1913-1918
56. Maraskovsky E., O'Reilly L.A., Teepe M., Corcoran L.M., Peschon J.J., and Strasser A. Bcl-2 can rescue T lymphocyte development in interleukin-7 receptor-deficient mice but not in mutant rag-1-/- mice. Cell 89 (1997) 1011-1019
57. Maraskovsky E., Teepe M., Morrissey P.J., Braddy S., Miller R.E., Lynch D.H., et al. Impaired survival and proliferation in IL-7 receptor-deficient peripheral T cells. J Immunol 157 (1996) 5315-5323
58. Mazzucchelli R., and Durum S.K. Interleukin-7 receptor expression: intelligent design. Nat Rev Immunol 7 (2007) 144-154
59. Moriggl R., Sexl V., Piekorz R., Topham D., and Ihle J.N. Stat5 activation is uniquely associated with cytokine signaling in peripheral T cells. Immunity 11 (1999) 225-230
60. Munitic I., Williams J.A., Yang Y., Dong B., Lucas P.J., El Kassar N., et al. Dynamic regulation of IL-7 receptor expression is required for normal thymopoiesis. Blood 104 (2004) 4165-4172
61. Namen A.E., Lupton S., Hjerrild K., Wignall J., Mochizuki D.Y., Schmierer A., et al. Stimulation of B-cell progenitors by cloned murine interleukin-7. Nature 333 (1988) 571-573
62. Nosaka T., van Deursen J.M., Tripp R.A., Thierfelder W.E., Witthuhn B.A., McMickle A.P., et al. Defective lymphoid development in mice lacking Jak3. Science 270 (1995) 800-802
63. Nyga R., Pecquet C., Harir N., Gu H., Dhennin-Duthille I., Regnier A., et al. Activated STAT5 proteins induce activation of the PI 3-kinase/Akt and Ras/MAPK pathways via the Gab2 scaffolding adapter. Biochem J 390 (2005) 359-366
64. O'Shea J.J., Husa M., Li D., Hofmann S.R., Watford W., Roberts J.L., et al. Jak3 and the pathogenesis of severe combined immunodeficiency. Mol Immunol 41 (2004) 727-737
65. Onishi M., Nosaka T., Misawa K., Mui A.L., Gorman D., McMahon M., et al. Identification and characterization of a constitutively active STAT5 mutant that promotes cell proliferation. Mol Cell Biol 18 (1998) 3871-3879
66. Osborne L.C., Dhanji S., Snow J.W., Priatel J.J., Ma M.C., Miners M.J., et al. Impaired CD8 T cell memory and CD4 T cell primary responses in IL-7R alpha mutant mice. J Exp Med 204 (2007) 619-631
67. Pacheco R., Gallart T., Lluis C., and Franco R. Role of glutamate on T-cell mediated immunity. J Neuroimmunol 185 (2007) 9-19
68. Pallard C., Stegmann A.P., van Kleffens T., Smart F., Venkitaraman A., and Spits H. Distinct roles of the phosphatidylinositol 3-kinase and STAT5 pathways in IL-7-mediated development of human thymocyte precursors. Immunity 10 (1999) 525-535
69. Park J.H., Yu Q., Erman B., Appelbaum J.S., Montoya-Durango D., Grimes H.L., et al. Suppression of IL7Ralpha transcription by IL-7 and other prosurvival cytokines: a novel mechanism for maximizing IL-7-dependent T cell survival. Immunity 21 (2004) 289-302
70. Pellegrini M., Bouillet P., Robati M., Belz G.T., Davey G.M., and Strasser A. Loss of Bim increases T cell production and function in interleukin 7 receptor-deficient mice. J Exp Med 200 (2004) 1189-1195
71. Peschon J.J., Morrissey P.J., Grabstein K.H., Ramsdell F.J., Maraskovsky E., Gliniak B.C., et al. Early lymphocyte expansion is severely impaired in interleukin 7 receptor-deficient mice. J Exp Med 180 (1994) 1955-1960
72. Porter B.O., Scibelli P., and Malek T.R. Control of T cell development in vivo by subdomains within the IL-7 receptor alpha-chain cytoplasmic tail. J Immunol 166 (2001) 262-269
73. Puel A., Ziegler S.F., Buckley R.H., and Leonard W.J. Defective IL7R expression in T(-)B(+)NK(+) severe combined immunodeficiency. Nat Genet 20 (1998) 394-397
74. Rajnavolgyi E., Benbernou N., Rethi B., Reynolds D., Young H.A., Magocsi M., et al. IL-7 withdrawal induces a stress pathway activating p38 and Jun N-terminal kinases. Cell Signal 14 (2002) 761-769
75. Rathmell J.C., Farkash E.A., Gao W., and Thompson C.B. IL-7 enhances the survival and maintains the size of naive T cells. J Immunol 167 (2001) 6869-6876
76. Rich B.E., and Leder P. Transgenic expression of interleukin 7 restores T cell populations in nude mice. J Exp Med 181 (1995) 1223-1228
77. Schluns K.S., Kieper W.C., Jameson S.C., and Lefrancois L. Interleukin-7 mediates the homeostasis of naive and memory CD8 T cells in vivo. Nat Immunol 1 (2000) 426-432
78. Schmelzle T., and Hall M.N. TOR, a central controller of cell growth. Cell 103 (2000) 253-262
79. Sexl V., Diehl J.A., Sherr C.J., Ashmun R., Beach D., and Roussel M.F. A rate limiting function of cdc25A for S phase entry inversely correlates with tyrosine dephosphorylation of Cdk2. Oncogene 18 (1999) 573-582
80. Sharfe N., Dadi H.K., and Roifman C.M. JAK3 protein tyrosine kinase mediates interleukin-7-induced activation of phosphatidylinositol-3' kinase. Blood 86 (1995) 2077-2085
81. Shelton J.G., Steelman L.S., Lee J.T., Knapp S.L., Blalock W.L., Moye P.W., et al. Effects of the RAF/MEK/ERK and PI3K/AKT signal transduction pathways on the abrogation of cytokine-dependence and prevention of apoptosis in hematopoietic cells. Oncogene 22 (2003) 2478-2492
82. Sherr C.J., and Roberts J.M. CDK inhibitors: positive and negative regulators of G1-phase progression. Genes Dev 13 (1999) 1501-1512
83. Stahl M., Dijkers P.F., Kops G.J., Lens S.M., Coffer P.J., Burgering B.M., et al. The forkhead transcription factor FoxO regulates transcription of p27Kip1 and Bim in response to IL-2. J Immunol 168 (2002) 5024-5031
84. Surh C.D., Boyman O., Purton J.F., and Sprent J. Homeostasis of memory T cells. Immunol Rev 211 (2006) 154-163
85. Suzuki K., Nakajima H., Saito Y., Saito T., Leonard W.J., and Iwamoto I. Janus kinase 3 (Jak3) is essential for common cytokine receptor gamma chain (gamma(c))-dependent signaling: comparative analysis of gamma(c), Jak3, and gamma(c) and Jak3 double-deficient mice. Int Immunol 12 (2000) 123-132
86. Swainson L., Kinet S., Manel N., Battini J.L., Sitbon M., and Taylor N. Glucose transporter 1 expression identifies a population of cycling CD4+ CD8+ human thymocytes with high CXCR4-induced chemotaxis. Proc Natl Acad Sci USA 102 (2005) 12867-12872
87. Swainson L., Kinet S., Mongellaz C., Sourisseau M., Henriques T., and Taylor N. IL-7-induced proliferation of recent thymic emigrants requires activation of the PI3K pathway. Blood 109 (2007) 1034-1042
88. Swainson L., Verhoeyen E., Cosset F.L., and Taylor N. IL-7R alpha gene expression is inversely correlated with cell cycle progression in IL-7-stimulated T lymphocytes. J Immunol 176 (2006) 6702-6708
89. Tan J.T., Dudl E., LeRoy E., Murray R., Sprent J., Weinberg K.I., et al. IL-7 is critical for homeostatic proliferation and survival of naive T cells. Proc Natl Acad Sci USA 98 (2001) 8732-8737
90. Tanner J.W., Chen W., Young R.L., Longmore G.D., and Shaw A.S. The conserved box 1 motif of cytokine receptors is required for association with JAK kinases. J Biol Chem 270 (1995) 6523-6530
91. Vander H.M., Plas D.R., Rathmell J.C., Fox C.J., Harris M.H., and Thompson C.B. Growth factors can influence cell growth and survival through effects on glucose metabolism. Mol Cell Biol 21 (2001) 5899-5912
92. Vanhaesebroeck B., and Waterfield M.D. Signaling by distinct classes of phosphoinositide 3-kinases. Exp Cell Res 253 (1999) 239-254
93. Vidal A., and Koff A. Cell-cycle inhibitors: three families united by a common cause. Gene 247 (2000) 1-15
94. Vivanco I., and Sawyers C.L. The phosphatidylinositol 3-kinase AKT pathway in human cancer. Nat Rev Cancer 2 (2002) 489-501
95. von-Freeden-Jeffry U., Vieira P., Lucian L.A., McNeil T., Burdach S.E., and Murray R. Lymphopenia in interleukin (IL)-7 gene-deleted mice identifies IL-7 as a nonredundant cytokine. J Exp Med 181 (1995) 1519-1526
96. Wallace D.C. Mitochondria and cancer: warburg addressed. Cold Spring Harb Symp Quant Biol 70 (2005) 363-374
97. Wells W.A. Does size matter?. J Cell Biol 158 (2002) 1156-1159
98. Wieman H.L., Wofford J.A., and Rathmell J.C. Cytokine stimulation promotes glucose uptake via phosphatidylinositol-3 kinase/Akt regulation of Glut1 activity and trafficking. Mol Biol Cell 18 (2007) 1437-1446
99. Yao Z., Cui Y., Watford W.T., Bream J.H., Yamaoka K., Hissong B.D., et al. Stat5a/b are essential for normal lymphoid development and differentiation. Proc Natl Acad Sci USA 103 (2006) 1000-1005
100. Yu C.R., Young H.A., and Ortaldo J.R. Characterization of cytokine differential induction of STAT complexes in primary human T and NK cells. J Leukoc Biol 64 (1998) 245-258
101. Ziegler S.E., Morella K.K., Anderson D., Kumaki N., Leonard W.J., Cosman D., et al. Reconstitution of a functional interleukin (IL)-7 receptor demonstrates that the IL-2 receptor gamma chain is required for IL-7 signal transduction. Eur J Immunol 25 (1995) 399-404