We observed that sheep erythrocytes and, later, Cancer Stem Cells (CSCs) are spontaneously destroyed by circulating lymphocytes without prior immunization. These lymphocytes, subsequently referred to as Natural Killer Cells (NKC), are the first line of defense in the blood against viruses and cancer stem cells. Much of our research has used nutraceuticals to enhance NKC activity against cancer cells. Our initial discovery of the NKC occurred while carefully observing non-immunized mouse lymphocytes centrifuged onto a lawn of sheep Red Blood Cells (SRBC) on a microscope slide. These “killer” lymphocytes would completely destroy the surrounding foreign erythrocytes on contact within a 15-minute incubation at 37 °C, forming clear plaques in a lawn of SRBC. We were able to purify these killer cells at least fivefold using continuous isotonic bovine serum albumin gradients (density = 1.0498) of normal mouse spleen cells. After glutaraldehyde fixation and Giemsa staining, Nomarski microscopy showed that the killer cells were small to medium lymphocytes. Scanning electron microscopy revealed a rough surface for these cells. Subsequently, a lawn of K562 leukemic stem cells was used as a target for the lymphocytes. We observed binding to the cancer cells, followed by the destruction of their cell membranes, as shown by Nomarski microscopy. The “blebbing” destruction of the K562 membranes is visualized in the transmission and scanning electron microscopy images. Interestingly, the NKCs exhibit pseudopodia membranes that resemble fangs, allowing them to deposit their venom into the cancer cell. Additionally, one can observe the rough endoplasmic reticulum aligning itself on the side where destruction occurs, indicating the production of cytolytic proteins. We have devoted significant research to identifying nutraceuticals that enhance NKCs and overall immunity, with an emphasis on increasing bioavailability through micellized formulations, which will be presented.https://youtu.be/HNP1EAYLhOs?si=QmsD3xDo5C9FrRZw