Send to

Choose Destination
See comment in PubMed Commons below
Am J Reprod Immunol. 1995 May;33(5):354-66.

Presence of activated macrophages in a murine model of early embryo loss.

Author information

Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada.



Even though our knowledge of the phenomenon at play at the fetoplacental interface has greatly advanced during the past years, a complete understanding of the reasons why the developing embryo is not rejected by maternal immune effector cells remains largely unknown.


We have used immunohistochemistry with the macrophage-specific markers F4/80 and MHC II to study the relationship between decidual infiltration and resorption in murine models of embryo loss between days 6 and 10 of gestation.


Analysis of day 8 CBA/J x DBA/2 pregnancies has revealed 2 distinct populations of embryos. The majority (69.4%) expressed low levels of F4/80+ cells, but a minority (30.6%) expressed much higher level of the macrophage marker. In FBA/J x BALB/c, most embryos (91.7%) expressed low numbers of F4/80+ cells. As earlier experiments established that products of activated macrophages (TNF-alpha and nitric oxide) were implicated in embryo loss in this model, the activation status of the F4/80+ macrophages was assessed through the cell surface expression of MHC II. Again, a similar association was established: 30.6% of the CBA/J x DBA/2 embryos were infiltrated by significantly more MHC II+ cells than the control CBA/J x BALB/c mating. Finally, when coordinate expression of F4/80, MHC II and CD11b was assessed, it was found that an embryo significantly infiltrated by cells bearing one of the 3 markers was also heavily infiltrated by cells bearing the 2 other markers.


This study has shown that the augmented infiltration of the deciduum with maternal macrophages is an early event which precedes spontaneous abortion of the early embryo.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center