Leenen PJM, Radosevic K, Voerman JSA, Salomon B, van Rooijen N, Klatzmann D, van Ewijk W.
[toggle_content title=”Abstract”] In the normal mouse spleen, two distinct populations of dendritic cells (DC) are present that differ in microanatomical location. The major population of marginal DC is found in the “marginal zone bridging channels” and extends into the red pulp. The interdigitating cells (IDC) are localized in the T cell areas in the white pulp. The aim of the present study was to characterize these two splenic DC populations with regard to their phenotype, in vivo phagocytic function, and turnover. Both marginal DC and IDC are CD11c+ and CD13+, but only IDC are NLDC-145+ and CD8α+. Notably, both populations, when freshly isolated, express the macrophage markers F4/80, BM8, and Mac-1. To study the phagocytic capacity of these cells, we employed the macrophage “suicide” technique by injecting liposomes loaded with clodronate i.v. Marginal DC, but not IDC, were eliminated by this treatment. Phagocytosis of DiI-labeled liposomes by DC confirmed this finding. The two DC populations differed significantly with regard to their turnover rates, as studied in a transgenic mouse model of conditional depletion of DC populations with high turnover. In these mice, marginal DC were completely eliminated, but the IDC population remained virtually intact. From these data we conclude that the marginal DC population has a high turnover, in contrast to the IDC population. Taken together, the present results indicate that marginal DC and IDC represent two essentially distinct populations of DC in the mouse spleen. They differ not only in location, but also in phenotype, phagocytic ability, and turnover. [/toggle_content]
[toggle_content title=”Clodronate Liposome Parameters”] [custom_table]
Heterogeneity of Mouse Spleen Dendritic Cells: In Vivo Phagocytic Activity, Expression of Macrophage Markers, and Subpopulation Turnover.
The Journal of Immunology. 1998;160(5):2166–73.
|Clodronate Concentration||Total Lipid Concentration||Lipid Composition||Lipid Mole %||Liposome Type||Control Liposomes|
|10 mg/ml 1||46 mg/ml||EPC/Chol||86/14||MLV||none|
1Clodronate and lipid concentrations assumed based on information in paper (dosed 2 mg in 0.2 ml).[/custom_table] [/toggle_content] [toggle_content title=”Animals and Dosing”] [custom_table]
|Animal Description||Clodronate Dose||Dosing Method/Site||Target Phagocytes||Adjunct Dosing?||Adjunct Dosing Route|
|C57BL/6, C57BL/10 mice 2, 8-20 w||200 µl||intravenous||CD11c+, CD13+, F4/80+, etc. splenic DC / IDC||no||NA|
2Base or background strain. Variants, mutants or otherwise genetically altered strains were also used in this study.[/custom_table] [/toggle_content] [toggle_content title=”Notes”]
- Clodronate and lipid concentrations assumed based on referenced paper, although references provide little information as to final clodronate concentrations.
- Reference for clodronate liposome preparation – van Rooijen N, Sanders A. Liposome mediated depletion of macrophages: mechanism of action, preparation of liposomes and applications. Journal of immunological methods. 1994;174(1-2):83–93.
- Splenic marginal, but not interdigitated, dendritic cells were completely depleted at 48 h post-liposomal clodronate treatment as judged by histological analysis.