title: Possible roles of KIR2DL4 expression on uNK cells in human pregnancy.
abstract: OBJECTIVE
  To investigate possible roles of the natural killer (NK) cell receptor killer immunoglobulin-like receptor (KIR)2DL4 expressed on uterine NK (uNK) cells during pregnancy, we investigated KIR2DL4 expression on uNK cells isolated from patients with early recurrent spontaneous abortion (RSA) and normal early pregnancy women, and functions of KIR2DL4 was analyzed in vitro. METHODS OF THE STUDY: Semi-quantitative RT-PCR analysis was introduced to detect KIR2DL4 messenger RNA (mRNA) expression on uNK cells. Cytotoxicity and cytokine production as the result of interaction of KIR2DL4 and its ligand human leukocyte antigen (HLA)-G were analyzed in vitro with lactic dehydrogenase releasing method and enzyme-linked immunosorbent assay, respectively.
  
  
  RESULTS
  No significant difference in KIR2DL4 mRNA expression was observed, while the KIR2DL4 protein level in isolated uNK cells is much higher in normal controls than that in RSA patients. Data showed that HLA-G transfection could not reverse the lysis of uNK against HLA-G transfected K562 cells but induced cytokine production. Furthermore, we demonstrated that, via KIR2DL4, membrane-bound HLA-G could induce high cytotoxicity and cytokine production in a high cytotoxic, IL-2 dependent human NK cell line NK-92 cells.
  
  
  CONCLUSIONS
  Our data suggest that KIR2DL4 might play a crucial implication for human pregnancy.
authors.affiliation: Medical Research Center, Taizhou Hospital of Zhejiang Province, Wenzhou Medical College, Linhai, Zhejiang, People's Republic of China. yanwhcom@yahoo.com
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Yan
authors.forename: Aifen
authors.initials: A
authors.lastname: Lin
authors.forename: Bao-Guo
authors.initials: BG
authors.lastname: Chen
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Zhou
authors.forename: Mei-Zhen
authors.initials: MZ
authors.lastname: Dai
authors.forename: Xue-Jiao
authors.initials: XJ
authors.lastname: Chen
authors.forename: Ling-Hong
authors.initials: LH
authors.lastname: Gan
authors.forename: Min
authors.initials: M
authors.lastname: Zhu
authors.forename: Wei-Wu
authors.initials: WW
authors.lastname: Shi
authors.forename: Bo-Li
authors.initials: BL
authors.lastname: Li
mesh_terms: D000026:Abortion, Habitual / Q000276:immunology* / Q000378:metabolism; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006680:HLA Antigens / Q000276:immunology; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism*; D011247:Pregnancy / Q000276:immunology* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011971:Receptors, Immunologic / Q000276:immunology / Q000378:metabolism*; D054340:Receptors, KIR; D054345:Receptors, KIR2DL4; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014599:Uterus / Q000276:immunology* / Q000378:metabolism
chemical_list: D016207:Cytokines; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; C515079:KIR2DL4 protein, human; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D054345:Receptors, KIR2DL4