Effective deletion of the <i>Lrp1</i> gene in elicited macrophages, bone marrow-derived macrophages, and Kupffer cells.

<p>(<b>a</b>) Quantitative real-time PCR was performed on bone marrow derived macrophages to determine <i>Lrp1</i> levels (**p = 0.005, Student’s t-test comparing LRP1+/+ with macLRP1-/-, n = 3 independent experiments). (<b>b</b>) Elicited peritoneal-derived macrophages from LRP1+/+ and macLRP1-/- mice were measured for their ability to internalize activated forms of ¹²⁵I-labeled α₂-macroglobulin (*p = 0.003, Student’s t-test comparing LRP1+/+ with macLRP1-/-, n = 2 independent experiments). (<b>c</b>) macLRP1-/- (open symbols) and LRP1+/+ (closed symbols) mice were injected with ¹²⁵I-α₂M* alone or with excess RAP. Plasma was sampled over time and counted. Counts were normalized to the amount of radioactivity detected at 1 min following injection. (¹²⁵I-α₂M*, n = 6; ¹²⁵I-α₂M* + RAP, n = 3). Error bars denote SEM. (<b>d-i</b>) Formalin-fixed paraffin-embedded liver sections from Western-fed LRP1+/+ (<b>d-f</b>) and macLRP1-/- mice (<b>g-i</b>) were stained with Alexa 488-anti-Mac-2 (<b>d,g</b>) and Alexa 546-anti-LRP1 (<b>e,h</b>) antibodies. Fluorescent channels merged with phase contrast images of the tissue (<b>f,i</b>) show yellow co-staining of LRP1 and Mac-2 in LRP1+/+ livers (<b>f</b>). No co-staining was observed in the macLRP1-/- livers (<b>i</b>). Livers from three sibling pairs of mice were stained. Representative fields from one pair are shown.