title: Uterine natural killer cells in peri-implantation endometrium from women with repeated implantation failure after IVF.
abstract: Several studies have suggested that endometrial uNK (CD56+) cells may play a role in implantation. The aim of this study was to investigate the number of CD56+, CD16+ and CD69+ cells in the unstimulated endometrium of women with recurrent implantation failure after IVF. The percentage of stromal cells positive for CD56, CD16 and CD69 was identified by immunocytochemistry in endometrial biopsies from 15 normal control women and 40 women with recurrent implantation failure. All biopsies were obtained on days LH+7 to LH+9. The density of CD56+ cells in endometrium from women with repeated implantation failure after IVF [median (range) CD56+ cell density=14.5% (1.5-71.4%)] was significantly higher (P=0.005) than in endometrium from control women [5% (2.1-19.2%)]. There was no significant difference in the densities of CD16+ and CD69+ cells in the endometrium from women in the two groups. The increased density of CD56+ cells in the endometrium of women with recurrent implantation failure suggests that these cells are directly involved in the implantation process; alternatively this may indicate a general endometrial defect in these women, which leads to the inability of the embryo to implant.
authors.affiliation: Biomedical Research Unit, Jessop Wing, Tree Root Walk, Sheffield S10 2SF, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Tuckerman
authors.forename: Najat
authors.initials: N
authors.lastname: Mariee
authors.forename: Alka
authors.initials: A
authors.lastname: Prakash
authors.forename: Tin C
authors.initials: TC
authors.lastname: Li
authors.forename: Susan
authors.initials: S
authors.lastname: Laird
mesh_terms: D015703:Antigens, CD / Q000032:analysis / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis / Q000276:immunology; D019002:CD56 Antigen / Q000032:analysis / Q000276:immunology; D010064:Embryo Implantation; D020964:Embryo Loss / Q000276:immunology*; D004717:Endometrium / Q000276:immunology* / Q000473:pathology; D005260:Female; D005307:Fertilization in Vitro; D005455:Fluorescent Antibody Technique; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D037181:Lectins, C-Type / Q000032:analysis / Q000276:immunology; D011247:Pregnancy / Q000276:immunology*; D017452:Receptors, IgG / Q000032:analysis / Q000276:immunology; D017154:Stromal Cells / Q000276:immunology; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D019002:CD56 Antigen; D037181:Lectins, C-Type; D017452:Receptors, IgG; D000099192:CD69 Antigens