In-house study on apoD interactions

Introduction
The study "ApoD Mediates Binding of HDL to LDL and to Growing T24 Carcinoma" was performed in collaboration between researchers at Mabtech and Karolinska Institutet. Braesch-Andersen et al. explore the interactions of ApolipoproteinD (apoD) in lipid metabolism. 

About apoD
In human plasma, apoD is a glycoprotein mainly found on HDL, but also on LDL and VLDL. Unlike other apolipoproteins, apoD is not only located on lipoproteins, but in a variety of cells; apoD is expressed in brain, spleen, testes, and mammary cysts. ApoD shares little sequence similarity with other apolipoproteins. Instead, it is a lipocalin that binds to hydrophobic ligands such as progesterone, pregnenolone, and arachidonic acid. Previous studies have linked apoD to the resistance to oxidative stress and neuroprotection. This study adds to the understanding of the role of apoD in lipid trafficking. 

Tools used
New monoclonal antibodies against human apoD have been developed at Mabtech for this study. Moreover, our antibodies against human apoA1, apo B, apoE, apoJ, and apoH were also used. Then, a detergent-free dual-specific ELISA was established to study interactions between lipoproteins, for example, by capturing apoD and detecting apoB (Figure 1). Detergent-free ELISAs were performed to maintain the integrity of lipoproteins, the addition of detergents abolished the observed interactions. Biosensor experiments were run as a complement. 

Conclusions
This study establishes apoD as a link in the transient interaction between HDL and LDL and between HDL and cells. 

Learn more about apolipoproteins