passages.id: split_1_test_2833_passage
passages.type: progene_text
passages.text: These observations indicate that linked regulatory elements within the genomic clones are sufficient to allow appropriate expression of KIRs in mice , and illustrate that the presence of the natural ligands for these receptors , in the form of human MHC class I proteins , is not necessary for the expression of the KIRs observed in these mice .