CD16n

CD16n is not a widely recognized or official name for a protein in major immunology references. In human immunology, the CD16 family is typically referred to by the markers CD16a and CD16b, corresponding to the FCGR3A and FCGR3B genes. The suffix “n” may appear informally in some papers to denote a novel, nonstandard, or context-specific designation, but it does not reflect a widely accepted category.

CD16 refers to Fc gamma receptor III, a receptor for immunoglobulin G. CD16a (FcγRIIIa) is expressed on natural killer cells and some macrophages, while CD16b (FcγRIIIb) is GPI-anchored on neutrophils. These receptors mediate antibody-dependent cellular cytotoxicity and phagocytosis and participate in immune complex handling. The two main isoforms differ in genetic location, tissue distribution, and signaling potential.

If a manuscript uses “CD16n,” readers should examine the authors’ nomenclature to determine what is meant. It could denote an alternate isoform, a species-specific sequence, a splice variant, a truncated receptor, or simply a labeling artifact. Without explicit definition in the source, the term remains ambiguous.

Polymorphisms in FCGR3A (CD16a) influence affinity for IgG and responses to therapeutic antibodies such as rituximab and cetuximab, while FCGR3B (CD16b) copy number variation affects neutrophil function and immune complex handling. These established findings underscore the importance of precise naming, as nonstandard terms like “CD16n” require clear definitions to avoid confusion.

In summary, CD16n is not a standard designation in current immunology databases; accurate interpretation relies on source context and alignment with CD16a (FCGR3A) and CD16b (FCGR3B) biology.