It has been suggested that the copper-S100A12 complex might sequester copper as part of the nutritional immunity response, similarly to how calprotectin (S100A8/S100A9, also known as the cystic fibrosis antigen, calgranulin A/B, and MRP-8/9) sequesters metals [44]. This evidence concerns the gene S100A8 and cystic fibrosis.