The immune cells
that fight first.
Our immune system has two layers. Adaptive immunity, what vaccines train, takes time to build a response. Innate immunity acts immediately, the moment something suspicious appears. NK cells are the most aggressive responders in the innate system, capable of killing cancer cells and virus-infected cells on contact.
When NK cells weaken, the body becomes more vulnerable. Aging, chronic stress, certain medications, and some cancers suppress NK cell activity. NK cell therapy reverses this by expanding and activating the patient's own cells outside the body, then reinfusing them in larger numbers and combat-ready state.
Unlike T-cells which need prior antigen exposure, NK cells recognise abnormal cells through pattern detection. They identify cells missing the normal "self" markers (often cancer cells) or displaying stress signals (often virus-infected cells) and kill them directly, no training required.
NK cells target cancer cells that have downregulated MHC-I molecules, a common way tumours try to hide from T-cells. This makes NK cells particularly valuable as cancer surveillance. They can detect malignant cells that have escaped other immune mechanisms.
NK cells are the body's primary defense against viral infections in the first 72 hours after exposure, before adaptive immunity is activated. Supporting NK cell numbers and function may help the body respond more effectively to both acute viral illness and chronic viral infections.
In 23C's protocol, harvested NK cells are cultured for 1 to 2 weeks with interleukin-2 (IL-2) and other activating factors. This expands the cell count many times over and shifts them into a more aggressive anti-cancer, anti-viral state before reinfusion.
NK cell therapy has one of the lowest side-effect profiles among cell-based immunotherapies. Compared to CAR-T or checkpoint inhibitors, which can trigger severe inflammatory reactions, NK therapy typically produces only mild, transient effects like brief fever or fatigue after infusion.
