TY - JOUR
T1 - A human interleukin 3 analog with increased biological and binding activities
AU - Lopez, A. F.
AU - Shannon, M. F.
AU - Barry, S.
AU - Phillips, J. A.
AU - Cambareri, B.
AU - Dottore, M.
AU - Simmons, P.
AU - Vadas, M. A.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1992
Y1 - 1992
N2 - Human interleukin 3 (IL-3) variants generated by site-directed mutagenesis were analyzed in multiple biological and binding assays to identify residues critical for IL-3 activity. Two mutants carrying substitutions in the predicted hydrophilic region within the first α-helix, [Ala21,Leu22]IL-3 and [Ala21Leu22,Ala25IL-3 showed loss of biological activity and high-affinity binding. Mutants in a second predicted hydrophilic region, [Ala44Leu45Ala46]IL-3 and [Ala44,Ala46]IL-3, however, showed similar biological and binding activities to wild-type IL-3. Mutations in a C-terminal hydrophilic region that overlaps the fourth predicted α-helix led to either loss or gain of function. IL-3 analogs [Glu104,Asp105]-, [Leu108]-, [Asn108]-, [Thr108]-, and [Ala101,Leu108]IL-3 were less active than wild-type IL-3, whereas [Ala101,]IL-3 and [Val116,]IL-3 were 2- to 3-fold more potent. Significantly, the double mutant [Ala101,Val116,]IL-3 exhibited a 15-fold greater potency than native IL-3. Receptor binding studies showed that [Ala101,Val116,]IL-3 exhibited increased binding to the high- and low-affinity receptors of monocytes. These results show the generation of an IL-3 analog with increased biological and binding activities and support a model where the C terminus of IL-3 interacts with the a chain of the IL-3 receptor, making this region a useful focus for the development of more potent IL-3 agonists or antagonists.
AB - Human interleukin 3 (IL-3) variants generated by site-directed mutagenesis were analyzed in multiple biological and binding assays to identify residues critical for IL-3 activity. Two mutants carrying substitutions in the predicted hydrophilic region within the first α-helix, [Ala21,Leu22]IL-3 and [Ala21Leu22,Ala25IL-3 showed loss of biological activity and high-affinity binding. Mutants in a second predicted hydrophilic region, [Ala44Leu45Ala46]IL-3 and [Ala44,Ala46]IL-3, however, showed similar biological and binding activities to wild-type IL-3. Mutations in a C-terminal hydrophilic region that overlaps the fourth predicted α-helix led to either loss or gain of function. IL-3 analogs [Glu104,Asp105]-, [Leu108]-, [Asn108]-, [Thr108]-, and [Ala101,Leu108]IL-3 were less active than wild-type IL-3, whereas [Ala101,]IL-3 and [Val116,]IL-3 were 2- to 3-fold more potent. Significantly, the double mutant [Ala101,Val116,]IL-3 exhibited a 15-fold greater potency than native IL-3. Receptor binding studies showed that [Ala101,Val116,]IL-3 exhibited increased binding to the high- and low-affinity receptors of monocytes. These results show the generation of an IL-3 analog with increased biological and binding activities and support a model where the C terminus of IL-3 interacts with the a chain of the IL-3 receptor, making this region a useful focus for the development of more potent IL-3 agonists or antagonists.
KW - Allergy
KW - Function
KW - Growth factors
KW - Hemopoiesis
UR - http://www.scopus.com/inward/record.url?scp=0027085704&partnerID=8YFLogxK
U2 - 10.1073/pnas.89.24.11842
DO - 10.1073/pnas.89.24.11842
M3 - Article
C2 - 1465408
AN - SCOPUS:0027085704
SN - 0027-8424
VL - 89
SP - 11842
EP - 11846
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 24
ER -