I picked this paper up from another IV page (TCRT by frank303) so credit noted. But here is a link to a Cell paper in which neutrophils (PMNs) are studied for anti tumor effects. It is animal model data testing a variety of human tumors in a mice transplant model and showing profound systemic anti tumor effects. This discovery is not from any specific company its U of Chicago research group. There are a few companies working on PMNs in treatments, but this study has identified what PMNs make that efficiently kills tumor cells. And it is a remarkable simple finding that an enzyme called elastase by its self appears to selectively activate programmed cell death in tumor cells. It’s a real wow factor discovery that will change this field profoundly.

http://www.sciencedirect.com/science/article/pii/S0092867421004955. Careful those easily triggered it’s a science direct link.

Edit
There are a couple companies doing cell therapies using PMNs but none as yet using this simple enzyme as a biologic drug. That will change very very soon. This is a discovery of a life time

Edit. There is a non public company taking this forward into trials Onchilles they are about to do a series A. Credit here goes to a poster Relaxx who has a few very informative posts on start ups in this innate immunity space. Much gratitude to these most excellent posters. That board is private so most will not have access, thus my linking the Cell paper.