Natural Killer (NK) Cells

What are Natural Killer (NK) cells?

Natural killer (NK) cells are lymphocytes of the innate immune system. A key feature of NK cells is their ability to recognize a wide range of cells in distress [1], particularly tumor cells and cells infected with viruses. They combine both direct effector functions against their cellular targets and participate in the generation, shaping and maintenance of a multicellular immune response.

NK cells uses killing mechanism such as apoptosis (cell shrinkage) and necrosis (cell rupture) on unrecognizable cells. They also communicate with other immune cells, e.g. T cells and antigen presenting cells (APC), to alert them of the presence of “invaders”.

In layman terms, NK cells kill cells they do not recognize [2] (e.g. cancer cells, mutated cells, infected cells). They act as “immigration officers” or “policemen” in your own body by coming into contact with other cells and initiate “self – marker” recognition. Healthy cells containing proper “self-markers” are ignored by NK cells while infected/cancer cells lacking these “self-markers” trigger NK cell killing immediately upon contact. [3]

Beneficial effects from NK cells therapy include anti-cancer, boost immunity, reduction of allergies and dormant infections.

[1] Natural killer cell therapies. Nature. 2024 Feb;626(8000):727-736.
[2] Natural killer cell recognition of missing self. Nat Immunol. 2008 May;9(5):477-80.
[3] Functions of natural killer cells. Nat Immunol 9, 503–510 (2008)

Projects in progress

Stage of Development

Discovery Preclinical Phase I Phase II Phase III
Completed
Completed
Preparation

We have developed state of the art magnetic separation technique to isolate and purify untouched NK cells from whole blood. Pure NK cells are expanded before subjected to detailed flow cytometry analysis.

NK(CD56+) cell quality of > 99% purity is consistently achieved in every isolation and expansion experiment. NK cells expanded using our proprietary protocol also increases the cytotoxicity of NK cells leading to higher potency.

Mechanism of Action

NK cells kill cells they do not recognize with 3 different mechanisms: Apoptosis (cell shrink until it implodes into smaller pieces), Necrosis (cell rupture, bursting out all internal structures) and Pyroptosis (cell perforated with holes, leaking out all internal structures)

Apoptosis: Cell Shrinkage

Necrosis: Cell rupture

Pyroptosis: Pore formation, cell leakage

NK Cells use cell surface markers to initiate recognition. Healthy cells contain markers to inhibit NK cell killing. Infected/cancer cells do not have those markers to stop NK cell killing. Some may even contain markers that trigger NK cell killing. NK cells are also able to alert other immune cells, e.g. T cells and antigen presenting cells (APC), to the presence of “invaders”.

NK cells in culture over 14 days