KLRK1 and obesity due to melanocortin 4 receptor deficiency: Aside from the characterization of total NK cells, the impact of obesity on the CD56dim and CD56bright subset-specific NK cell phenotype has recently been investigated, which demonstrated decreases in NKG2D-positive and CD69-positive CD56dim NK cells, while there was an increase in NKG2D-positive CD56bright NK cells in obese people.