A lipoprotein lipase (LPL)-specific monoclonal antibody, 88B8, that abolishes the binding of LPL to GPIHBP1

TY - JOUR

T1 - A lipoprotein lipase (LPL)-specific monoclonal antibody, 88B8, that abolishes the binding of LPL to GPIHBP1

AU - Allan, Christopher M

AU - Larsson, Mikael

AU - Hu, Xuchen

AU - He, Cuiwen

AU - Jung, Rachel S

AU - Mapar, Alaleh

AU - Voss, Constance

AU - Miyashita, Kazuya

AU - Machida, Tetsuo

AU - Murakami, Masami

AU - Nakajima, Katsuyuki

AU - Bensadoun, André

AU - Ploug, Michael

AU - Fong, Loren G

AU - Young, Stephen G

AU - Beigneux, Anne P

N1 - Copyright © 2016, The American Society for Biochemistry and Molecular Biology.

PY - 2016/10

Y1 - 2016/10

N2 - LPL contains two principal domains: an aminoterminal catalytic domain (residues 1.297) and a carboxylterminal domain (residues 298.448) that is important for binding lipids and binding glycosylphosphatidylinositolanchored high density lipoprotein binding protein 1 (GPIHBP1) (an endothelial cell protein that shuttles LPL to the capillary lumen). The LPL sequences required for GPIHBP1 binding have not been examined in detail, but one study suggested that sequences near LPL's carboxyl terminus (residues ∼403-438) were crucial. Here, we tested the ability of LPLspecific monoclonal antibodies (mAbs) to block the binding of LPL to GPIHBP1. One antibody, 88B8, abolished LPL binding to GPIHBP1. Consistent with those results, antibody 88B8 could not bind to GPIHBP1-bound LPL on cultured cells. Antibody 88B8 bound poorly to LPL proteins with amino acid substitutions that interfered with GPIHBP1 binding (e.g., C418Y, E421K). However, the sequences near LPL's carboxyl terminus (residues ∼403-438) were not sufficient for 88B8 binding; upstream sequences (residues 298. 400) were also required. Additional studies showed that these same sequences are required for LPL binding to GPIHBP1. In conclusion, we identified an LPL mAb that binds to LPL's GPIHBP1-binding domain. The binding of both antibody 88B8 and GPIHBP1 to LPL depends on large segments of LPL's carboxyl-terminal domain.

AB - LPL contains two principal domains: an aminoterminal catalytic domain (residues 1.297) and a carboxylterminal domain (residues 298.448) that is important for binding lipids and binding glycosylphosphatidylinositolanchored high density lipoprotein binding protein 1 (GPIHBP1) (an endothelial cell protein that shuttles LPL to the capillary lumen). The LPL sequences required for GPIHBP1 binding have not been examined in detail, but one study suggested that sequences near LPL's carboxyl terminus (residues ∼403-438) were crucial. Here, we tested the ability of LPLspecific monoclonal antibodies (mAbs) to block the binding of LPL to GPIHBP1. One antibody, 88B8, abolished LPL binding to GPIHBP1. Consistent with those results, antibody 88B8 could not bind to GPIHBP1-bound LPL on cultured cells. Antibody 88B8 bound poorly to LPL proteins with amino acid substitutions that interfered with GPIHBP1 binding (e.g., C418Y, E421K). However, the sequences near LPL's carboxyl terminus (residues ∼403-438) were not sufficient for 88B8 binding; upstream sequences (residues 298. 400) were also required. Additional studies showed that these same sequences are required for LPL binding to GPIHBP1. In conclusion, we identified an LPL mAb that binds to LPL's GPIHBP1-binding domain. The binding of both antibody 88B8 and GPIHBP1 to LPL depends on large segments of LPL's carboxyl-terminal domain.

U2 - 10.1194/jlr.m070813

DO - 10.1194/jlr.m070813

M3 - Journal article

C2 - 27494936

SN - 0022-2275

VL - 57

SP - 1889

EP - 1898

JO - Journal of Lipid Research

JF - Journal of Lipid Research

IS - 10

ER -