Fc receptor species specificity?

[celia516]

This is probably a really basic question: I'm setting up a flow cytometry experiment detecting a receptor-bound ligand on mouse macrophages with a fluorochrome-labeled antibody. Should I get an antibody produced in mouse or in another background? Someone in our lab said that if we get a mouse antibody, the Fc portion of the antibody will be recognized by the Fc receptors on our cells, since both are mouse-specific; hence we'll get non-specific binding and high background noise. This assumes that the Fc portion on an antibody made in goat is different than that of mouse and hence will not be recognized by mouse Fc receptors. But then someone else said that if we get a goat or rabbit antibody, they won't be recognized at all and we won't get any signal; I tend to agree with the former argument, since our antibody is binding to a ligand (that was made in human) and is not supposed to bind to anything murine; but I'm really new to flow cytometry and immunological assays in general, so I'm not 100% sure. Help???