Effect of age and CMV on NK cell subpopulations.
NK cells represent an important component of the innate immune response against infection and tumors. Age-associated changes in NK cell phenotype have been previously reported that can be responsible of functional NK cell deficiency. The aim of this work was to analyze the effect CMV seropositivity and aging on the distribution of NK cell subsets with a focus on the expression of cytotoxicity-related molecules and on the expression of CD94/NKG2 heterodimers and CD57 on these NK cell subsets. Our results show that CMV seropositivity in young individuals does not significantly affect peripheral blood NK cell percentage and NK cell subsets defined by the use of CD56 and CD16 markers. In contrast a significant increase in the percentage of NK cells is observed in elderly donors, all of them are CMV seropositive, when compared with young CMV seropositive subjects. A decrease in the percentage of CD56bright NK cells, either fully immature CD16 negative or CD16+ and an increase in the CD56-CD16+ subset are also found in the elderly. CMV seropositivity either in healthy young or elderly individuals is associated to the expression of CD94/NKG2C dimers and high expression of CD57on the CD56dimCD16+ NK cell subset. CD56-CD16+ NK cells, which are expanded in the elderly, show a decreased expression of granzymes A and B and an increased expression of CD94/NKG2C and CD57 in CMV seropositive young donors when compared with CMV seronegative young individuals. These results indicate that CMV and age have a different effect on NK cell phenotype and emphasize the relevance of including the determination of CMV serostatus in those studies addressed to analyze the immune response in the elderly.
IMIBIC, Reina Sofia University Hospital, University of Cordoba, Cordoba, Spain.
Carmen
C
Campos
IMIBIC, Reina Sofia University Hospital, University of Cordoba, Cordoba, Spain. Electronic address: alejandrapera@gmail.com.
Alejandra
A
Pera
Immunology Unit, University of Extremadura, Caceres, Spain.
Beatriz
B
Sanchez-Correa
IMIBIC, Reina Sofia University Hospital, University of Cordoba, Cordoba, Spain.
Corona
C
Alonso
Residencia Municipal de Mayores de Torrecampo, Cordoba, Spain.
Isabel
I
Lopez-Fernandez
Immunology Unit, University of Extremadura, Caceres, Spain.
Sara
S
Morgado
Immunology Unit, University of Extremadura, Caceres, Spain.
Raquel
R
Tarazona
IMIBIC, Reina Sofia University Hospital, University of Cordoba, Cordoba, Spain.
Rafael
R
Solana
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019002:CD56 Antigen / Q000378:metabolism; D018959:CD57 Antigens / Q000378:metabolism; D003586:Cytomegalovirus Infections / Q000201:enzymology / Q000276:immunology*; D005260:Female; D053804:Granzymes / Q000378:metabolism; D006801:Humans; D007694:Killer Cells, Natural / Q000201:enzymology / Q000821:virology*; D016131:Lymphocyte Subsets / Q000201:enzymology / Q000821:virology; D008297:Male; D051920:NK Cell Lectin-Like Receptor Subfamily D / Q000378:metabolism; D054353:Perforin / Q000378:metabolism; D055815:Young Adult
D019002:CD56 Antigen; D018959:CD57 Antigens; D051920:NK Cell Lectin-Like Receptor Subfamily D; D054353:Perforin; D053804:Granzymes
CD57; CD94; Granzyme; Immunosenescence; NKG2A; NKG2C; Natural Killer cells; Perforin