MK Cell

Direct and natural-killer cell mediated anti-cancer action

Mesodermal killer (“MK”) cells are a new, unique and patented class of engineered cellular medicine. The MK cell is capable of killing cancer cells directly, i.e. cancer cell cytotoxicity and capable of priming / activating natural killer (“NK”) cells (i.e. increasing the proliferation and/or cytotoxic activity of NK cells). The MK cell is named after the NK cell because it displays similar natural killer characteristics, but it is tissue engineered from mesodermal cells and is quite distinct and different from NK cells in its composition, function and characteristics. MK cells were derived from the novel cellular medicines platform invented by Professor Sir Martin Evans, 2007 Nobel Laureate in Physiology or Medicine.

MK cells have demonstrated significantly increased cytotoxicity (P<0.05) in validated in vitro models of chronic myelogenous leukaemia and plasma cell myeloma. Incubation with MK cells significantly increased (P<0.01) the cytotoxicity of NK cells in validated in vitro models of chronic myelogenous leukaemia and plasma cell myeloma.

The MK cells are patented and identified by a unique ‘finger print’ consisting of six unusual receptors detectable on the surface of the MK cells (CD16, CD96, CD112, CD137L, CD178, CD253 and CD277) and the absence of three more common cell surface markers (CD34, CD45 and CD56). The six receptors present on MKs confer key functions in direct cytotoxicity cells via contact-dependent cell lysis or antibody-dependent cell-mediated cytotoxicity (ADCC) and through the attraction and priming of NK cells.

A key advantage of the MK cells is that they are mesodermal cells, which are typically safe. There is good evidence that these mesodermal cells are safe in human subjects. Thus MK cells are cytotoxic, but are not expected to induce any of the side effects of other cytotoxic cellular therapies, such as Chimeric Antigen Receptor-T (CAR-T) cells. In particular, MK cells are not expected to induce cytokine release syndrome (CRS; aka cytokine storm), macrophage activation syndrome (MAS) and off-target effects.

 

Natural Killer cell priming:

 

slide showing Natural Killer cell priming

 

Direct cytotoxicity:

 

slide showing direct cytotoxicity