This is a section from a nodular mass on the foot of a dog. There is an area of dystrophic calcification to the left surrounded by macrophages and giant cells, with fibrous tissue on the right. They have little cytoplasm and often form aggregates or follicle type arrangements. . . Beside the nucleus there is often a clear halo in which the Golgi apparatus is present. These cells are rich in RER and RNA and the cytoplasm stains deep purple-red.
Plasma cells are very numerous in muco-cutaneous junctions eg lips, feet, perineum. . .
This photo includes vascular connective tissue within which there are mixed cells. The largest round cells with oval nuclei are macrophages. The smaller, denser stained round cells are plasma cells. A few neutrophils are also present just to the left of the centre. . . .