Does lymphoid macrophages secrete antibodies into the blood?

Answer 1

There's a lot we don't currently know about lymphoid (ED3) Macrophages but it's relatively safe to assume that they do not have any major role in secreting antibodies.

Macrophages tend to engulf and enzymatically destroy foreign objects in the body, this is their major purpose, if that object is coated in antibodies they're better at destroying it but they do not produce those antibodies themselves.

The only real way that macrophages affect antibody production is that after destruction of intruder they'll present elements of the intruder to another variety of immune cell which will then go on to produce antibodies, it's also possible that they will produce interleukins or other compounds to upregulate antibody production but again: macrophages are not known to produce antibodies.