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A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity
06:08

A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity

Published on: August 9, 2017

Age-related changes in natural killer cell receptors from childhood through old age

Aline Almeida-Oliveira1, Monique Smith-Carvalho, Luis Cristovão Porto

  • 1Bone Marrow Transplantation Center (CEMO), National Cancer Institute (INCA), Rio de Janeiro, RJ, Brazil. aline.almeida@bio.fiocruz.br

Human Immunology
|January 26, 2011
PubMed

Insights

Natural killer (NK) cell receptor expression changes with age, with decreased activating receptors in the elderly. Despite these changes, cytotoxic activity is maintained, possibly due to increased CD56(dim) cell numbers.

Area of Science:

  • Immunology
  • Aging Research
  • Cell Biology

Background:

  • Natural killer (NK) cell research often focuses on cell numbers and overall cytotoxic activity.
  • NK cell function is regulated by surface receptors: killer cell immunoglobulin-like receptors (KIRs), natural cytotoxicity receptors (NCRs), and C-type lectins.

Purpose of the Study:

  • To investigate the age-related expression of NK cell surface receptors across different cell types and subsets.
  • To analyze the association of specific KIR genotypes with advanced age.

Main Methods:

  • Flow cytometry was used to analyze receptor expression (KIRs, NCRs, C-type lectins, NKG2D) on T, NKT, and NK cells (CD56(dim) and CD56(bright) subsets) from childhood to old age.
  • KIR genotyping was performed.

Main Results:

  • Elderly individuals showed decreased expression of activating NK receptors (NKp30, NKp46) on NK cells and NKG2D on T cells.
  • KIR expression increased in the CD56(bright) NK cell subset in the elderly.
  • KIR2DL5 and KIR2DS3 genotypes were significantly associated with old age.
  • Cytotoxic activity remained preserved across all age groups.

Conclusions:

  • Age-associated alterations in NK cell receptor expression occur, particularly a decrease in activating receptors.
  • Preserved cytotoxic activity in the elderly may be a compensatory mechanism related to an increased number of CD56(dim) NK cells.
  • Further research is needed to understand how these NK receptor expression changes impact disease susceptibility.

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