B23

B23 is an alphanumeric designation that appears in several, unrelated contexts. It does not refer to a single concept, but rather to different entities identified by the same code.

In biology and medicine, B23 most often refers to nucleophosmin, a nucleolar phosphoprotein encoded by the NPM1 gene in humans. B23/nucleophosmin is involved in ribosome biogenesis and can shuttle between the nucleolus and the cytoplasm. It plays a role in centrosome duplication and responds to cellular stress. Mutations in NPM1 are associated with acute myeloid leukemia, particularly forms where NPM1 protein localization is altered.

In other domains, B23 functions as an informal or official designation in information systems, including transportation networks, consumer products, and scholarly catalogs. Because these uses are specific to each field, the meaning of B23 remains determined by its context, and no universal definition exists.