Proteomic characterization of CD56posCD57 NK cell subsets

ABSTRACT: NK cells are lymphocytes that provide a first defense against viral infections and cancer. They act (i) cytotoxic by killing virus-infected and tumorigenic cells and (ii) immune regulatory by releasing cytokines and chemokines. These innate immune cells are commonly further classified as CD56bright and CD56dim NK cells. Former studies confirmed immune regulatory CD56bright NK cells as progenitors of cytotoxic CD56dim NK cells. CD57 was previously described as T cell marker for senescence and terminal differentiation. Recent studies detected CD57+ and CD57- NK cells among the CD56dim NK cell population and suggested a fully mature developmental status for CD57+ NK cells. The recent NK cell maturation model includes CD34+ hematopoietic stem cells (HSC), which develop into CD56bright NK cells, later into CD56dimCD57- and finally into terminally maturated CD56dimCD57+ (1) (2) (3). The molecular mechanisms of human NK cell differentiation and maturation remain unknown to this date. We performed for the first time a proteomic analysis of these distinct developmental stages of human primary NK cells, isolated from overall 10 healthy human blood donors. CD56bright NK cells versusCD56dim and CD56dimCD57- versus CD56dimCD57+ NK cells were analyzed by using quantitative peptide sequencing, which revealed individual protein signatures (3400 proteins) of these different NK cell developmental stages. Notably, our data support the current NK cell differentiation model by highlighting both strong distinctions between CD56dim/bright NK cells and close relationships between CD57+/- NK cells on the proteomic level. Among the most prominent and conserved regulated proteins, we detected myosin IIa, Calvasculin and Calcyclin with very similar expression patterns. We investigated their sub-cellular localization and observed specific recruitment- and accumulation-events at the NK cell immunological synapse (NKIS) after NK activation.

INSTRUMENT(S): LTQ Orbitrap, instrument model

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Peripheral Blood

SUBMITTER: Lothar Jaensch  

PROVIDER: PRD000666 | Pride | 2013-01-23

REPOSITORIES: Pride