In immunology, a centrocyte generally refers to a B cell with a cleaved nucleus,[1] as may appear in e.g. follicular lymphoma.[2] Centrocytes are B cells that are found in the light zones of germinal centers. Centrocytes are the non-dividing progeny of centroblasts, and although they are relatively similar in size, centrocytes lack distinct nucleoli and are more irregularly shaped than centroblasts.[3] Centrocytes also express the cell-surface hypermutated B-cell receptor following AID activation. This hypermutated B-cell receptor allows centrocytes to compete for binding of the antigen, internalize it, and then express the processed peptides through their MHC class II receptor.[4] Centrocyte can also refer to a cell with a protoplasm that contains single and double granules of varying size stainable with hematoxylin, as seen in lesions of lichen planus,[1] or a nondividing, activated B cell that expresses membrane immunoglobulin.[1]