The eccentrically located nucleus of this plasma cell contains a lot of condensed chromatin that lies in lumps against the cell membrane, as well as a clear nucleolus. Note the double membrane surrounding the nucleus and a few nuclear pores. The cytoplasm is filled with large amounts of granular endoplasmic reticulum (RER) and otherwise contains a clear Golgi apparatus and some mitochondria. Note small granules towards the surface (secretory granules?) and parts of RER segregated by membrane (autophagosome?)
Abundant RER and Golgi apparatus are typical for cells with a large synthesis of proteins to be exported out of the cell, in this case immunoglobulins.