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bioRxiv · 10.1101/2021.04.19.440471

Multiparametric assessment of cellular lipid metabolism in hypercholesterolemia

Pfisterer, S. G.·Brock, I.·Kanerva, K.·Hlushchenko, I.·Paavolainen, L.·Ripatti, P.·Islam, M. M.·Kyttala, A.·Di Taranto, M. D.·di Frega, A. S.·Fortunato, G.·Kuusisto, J.·Horvath, P.·Ripatti, S.·Laakso, M.·Ikonen, E.
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Abstract

Systematic insight into cellular dysfunctions can improve understanding of disease etiology, risk assessment and patient stratification. We present a multiparametric high-content imaging platform enabling quantification of low-density lipoprotein (LDL) uptake and lipid storage in cytoplasmic droplets of primary leukocyte subpopulations. We validated this platform with samples from 65 individuals with variable blood LDL-cholesterol (LDL-c) levels, including familial hypercholesterolemia (FH) and non-FH subjects. We integrated lipid storage data into a novel readout, lipid mobilization, measuring the efficiency with which cells deplete lipid reservoirs. Lipid mobilization correlated positively with LDL uptake and negatively with hypercholesterolemia and age, improving differentiation of individuals with normal and elevated LDL-c. Moreover, combination of cell-based readouts with a polygenic risk score for LDL-c explained hypercholesterolemia better than the genetic risk score alone. This platform provides functional insights into cellular lipid trafficking from a few mls of blood and is applicable to dissect metabolic disorders, such as hypercholesterolemia. MotivationWe have limited information on how cellular lipid uptake and processing differ between individuals and influence the development of metabolic diseases, such as hypercholesterolemia. Available assays are labor intensive, require skilled personnel and are difficult to scale to higher throughput, making it challenging to obtain systematic functional cell-based data from individuals. To overcome this problem, we established a scalable automated analysis pipeline enabling reliable quantification of multiple cellular readouts, including lipid uptake, storage and mobilization, from different white blood cell populations. This approach provides new personalized insights into the cellular basis of hypercholesterolemia and obesity. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/440471v4_ufig1.gif" ALT="Figure 1"> View larger version (84K): org.highwire.dtl.DTLVardef@9222c1org.highwire.dtl.DTLVardef@27e289org.highwire.dtl.DTLVardef@89ba82org.highwire.dtl.DTLVardef@33c9cd_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Pfisterer, S. G., Brock, I., Kanerva, K., Hlushchenko, I., Paavolainen, L., Ripatti, P., Islam, M. M., Kyttala, A., Di Taranto, M. D., di Frega, A. S., Fortunato, G., Kuusisto, J., Horvath, P., Ripatti, S., Laakso, M., Ikonen, E.. 2021-04-19. Multiparametric assessment of cellular lipid metabolism in hypercholesterolemia. https://doi.org/10.1101/2021.04.19.440471

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