cd1

cd1 is a term that can refer to more than one concept in biology and biomedical research. The most common usage is in immunology, where CD1 refers to a family of lipid antigen–presenting glycoproteins related to the MHC class I family. In humans, the CD1 family includes CD1a, CD1b, CD1c, CD1d, and CD1e. These molecules are expressed on professional antigen-presenting cells such as dendritic cells, monocytes, and Langerhans cells, and they specialize in presenting lipid and glycolipid antigens to T cells. Unlike peptide-presenting MHC molecules, CD1 proteins present lipid antigens to T cell subsets such as invariant natural killer T (iNKT) cells, contributing to immune responses against mycobacterial infections, skin immunity, and autoimmunity. The different CD1 isoforms have distinct tissue distribution and lipid-binding properties, which influence their antigen repertoire and physiological roles.

In a separate scientific usage, CD-1 (often written with a dash) denotes an outbred mouse strain widely used in biomedical research. CD-1 mice are valued for high fecundity, robust vigor, and genetic diversity, making them useful for toxicology, teratology, and general screening studies. The strain originated from a Swiss outbred stock and is maintained by commercial vendors as an albino stock. Researchers compare results across inbred strains and outbred populations to assess variability and generalizability.

Outside these contexts, "cd1" may be encountered as a project-specific abbreviation or naming convention, and its meaning should be inferred from the field or accompanying terminology.