Zecher D, van Rooijen N, Rothstein DM, Shlomchik WD, Lakkis FG.
An innate response to allogeneic nonself mediated by monocytes.
The Journal of Immunology. 2009;183(12):7810.
[toggle_content title=”Abstract”] The mammalian innate immune system has evolved diverse strategies to distinguish self from microbial nonself. How the innate immune system distinguishes self-tissues from those of other members of the same species (allogeneic nonself) is less clear. To address this question, we studied the cutaneous hypersensitivity response of lymphocyte-deficient RAG-/- mice to spleen cells transplanted from either allogeneic or syngeneic RAG-/- donors. We found that RAG-/- mice mount a specific response to allogeneic cells characterized by swelling and infiltration of the skin with host monocytes/macrophages and neutrophils. The response required prior priming with allogeneic splenocytes or skin grafts and exhibited features of memory as it could be elicited at least 4 wk after immunization. Neither depletion of host NK cells nor rechallenging immunized mice with F1 hybrid splenocytes inhibited the response, indicating that the response is not mediated by NK cells. Depletion of host monocytes/macrophages or neutrophils at the time of rechallenge significantly diminished the response and, importantly, the adoptive transfer of monocytes from alloimmunized RAG-/- mice conferred alloimmunity to naive RAG-/- hosts. Unlike NK- and T cell-dependent alloresponses, monocyte-mediated alloimmunity could be elicited only when donor and responder mice differed at non-MHC loci. These observations indicate that monocytes mount a response to allogeneic nonself, a function not previously attributed to them, and suggest the existence of mammalian innate allorecognition strategies distinct from detection of missing self-MHC molecules by NK cells. [/toggle_content] [toggle_content title=”Clodronate Liposome Parameters”] [custom_table]
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 PBS

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 250 µl intravenous/tail vein CD115+ F4/80int monocytes; F4/80+
Gr-1int splenic monocytes/; CD115+ F4/80+ bone marrow
no NA

2 Base or background strain. Variants, mutants or otherwise genetically altered strains were also used in this study.

[/custom_table] [/toggle_content] [toggle_content title=”Notes”]
  1. Clodronate and lipid concentrations assumed based on referenced paper, although references provide little information as to final clodronate concentrations.
  2. 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.
[/toggle_content][toggle_content title=”Results”]
  1. % Control Cells Remaining Post-Clodronate Liposome Treatment [custom_table]
    Tissue 16 h 24 h 48 h
    Bone Marrow 40 75 130
    Blood Monocytes 5 10 110
    Spleen 1 1 1

    Numbers extrapolated from supplemental figure 1 in paper.[/custom_table]

  2. /monocytes or neutrophil depletion reduces the allogenic non-self response (pinnae swelling or DTH) by 50%.
  3. PBS control liposome administration does not affect the response.