title: Enumeration of NKG2C+ natural killer cells early following allogeneic stem cell transplant recipients does not allow prediction of the occurrence of cytomegalovirus DNAemia.
abstract: The role of Natural killer (NK) cells in the control of cytomegalovirus (CMV) infection in allogeneic stem cell transplant recipients has not been precisely characterized. The current study is aimed at investigating the potential role of NK cells expressing the activating receptor NKG2C in affording protection against the development of CMV DNAemia in patients exhibiting detectable CMV-specific CD8(+) T-cell responses early following transplantation. A total of 61 nonconsecutive patients were included in the study. Peripheral levels of CD56(bright) CD16(-/low) and CD56(dim) CD16(+) NKG2C(+) NK cells and CMV pp65/IE-1-specific IFN-γ-producing CD8(+) T-cells were enumerated by flow cytometry at days +30 and +60 after transplant. Neither the absolute number of NKG2C(+) NK cells, nor that of CD56(bright) CD16(-/low) and CD56(dim) CD16(+) NKG2C(+) NK-cell subsets at day 30 differed significantly between patients with or without subsequent CMV DNAemia. No significant correlation was found between levels of both NKG2C(+) NK-cell populations and the peak CMV DNA load within subsequent episodes of CMV DNAemia. The data indicate that enumeration of NKG2C(+) NK cells early after transplant is unlikely to be helpful in identifying those patients at highest risk of developing CMV DNAemia. Moreover, the data do not support a direct implication of NKG2C(+) NK cells in preventing the development of CMV DNAemia.
authors: Microbiology Service, Hospital Clínico Universitario, Fundación INCLIVA, Valencia, Spain.
authors: Estela
authors: E
authors: Giménez
authors: Hematology and Medical Oncology Service, Hospital Clínico Universitario, Fundación INCLIVA, Valencia, Spain.|Department of Medicine, School of Medicine, University of Valencia, Valencia, Spain.
authors: Carlos
authors: C
authors: Solano
authors: Hematology and Medical Oncology Service, Hospital Clínico Universitario, Fundación INCLIVA, Valencia, Spain.
authors: Paula
authors: P
authors: Amat
authors: Hematology Service, Hospital de La Princesa, Madrid, Spain.
authors: Rafael
authors: R
authors: de la Cámara
authors: Hematology Service Hospital Morales Meseguer, Murcia, Spain.
authors: José
authors: J
authors: Nieto
authors: Hematology Service, Hospital Ramón y Cajal, Madrid, Spain.
authors: Javier
authors: J
authors: López
authors: Hematology Service, Hospital de La Princesa, Madrid, Spain.
authors: Ana
authors: A
authors: Garcia-Noblejas
authors: Microbiology Service, Hospital Clínico Universitario, Fundación INCLIVA, Valencia, Spain.|Department of Microbiology, School of Medicine, University of Valencia, Valencia, Spain.
authors: David
authors: D
authors: Navarro
mesh_terms: D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003587:Cytomegalovirus / Q000235:genetics / Q000302:isolation & purification*; D003586:Cytomegalovirus Infections / Q000276:immunology* / Q000821:virology; D004279:DNA, Viral / Q000097:blood*; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000821:virology; D018655:Lymphocyte Count; D008297:Male; D055654:NK Cell Lectin-Like Receptor Subfamily C / Q000032:analysis*; D019562:Viral Load; D014766:Viremia
chemical_list: D004279:DNA, Viral; D055654:NK Cell Lectin-Like Receptor Subfamily C
keywords: IFNγ-producing CD8+ T-cells; NK cells; active CMV infection; allogeneic stem cell transplantation; cytomegalovirus