Serous demilune
（重定向自Demilunes of Heidenhain）
![](/Images/godic/202501/08/Gray10252032.png")
A serous demilune or Crescents of Gianuzzi is a cap in the shape of a half-moon (hence the name "demilune") on some salivary glands.
Serous demilunes are the serous cells at the distal end of mucous tubuloalveolar secretory unit of certain salivary glands. These demilune cells secrete the proteins that contain the enzyme lysozyme, which degrades the cell walls of bacteria. In this way, lysozyme confers antimicrobial activity to mucus.