An LPL–specific monoclonal antibody, 88B8, that abolishes the binding of LPL to GPIHBP1[S]

Journal of Lipid Research

Loren G. Fong¹  Anne P. Beigneux²  Cuiwen He³  Mikael Larsson³  Alaleh Mapar³  Stephen G. Young³  Xuchen Hu³  Rachel S. Jung³  Constance Voss³  Christopher M. Allan³  André Bensadoun⁴  Michael Ploug⁵  Tetsuo Machida⁶  Masami Murakami⁶  Kazuya Miyashita⁶  Katsuyuki Nakajima⁶ 

[1] Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen N, Denmark;To whom correspondence should be addressed. (A.P.B.);Departments of Medicine University of California Los Angeles, Los Angeles, CA;Division of Nutritional Science, Cornell University, Ithaca, NY;Finsen Laboratory, Rigshospitalet, Copenhagen N, Denmark;Gunma University, Graduate School of Medicine, Maebashi, Japan;

关键词: chylomicrons;    endothelial cells;    lipids/chemistry;    lipolysis and fatty acid metabolism;    triglycerides;    lipoprotein lipase;   

DOI  :  

来源: DOAJ

【 摘 要 】

LPL contains two principal domains: an amino-terminal catalytic domain (residues 1–297) and a carboxyl-terminal domain (residues 298–448) that is important for binding lipids and binding glycosylphosphatidylinositol-anchored 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 LPL-specific 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.

【 授权许可】

Unknown