SubComdTaco writes "Harvard has announced their approach towards an implantable cancer vaccine (press release here). To anyone familiar with how the immune system works, this appears to be a synthetic lymph node, an intriguing bit of biomimicry. From the Science Daily article: 'A cancer vaccine carried into the body on a carefully engineered, fingernail-sized implant is the first to successfully eliminate tumors in mammals, scientists recently reported in the journal Science Translational Medicine. The new approach, pioneered by bioengineers and immunologists at Harvard University, uses plastic disks impregnated with tumor-specific antigens and implanted under the skin to reprogram the mammalian immune system to attack tumors. The new paper describes the use of such implants to eradicate melanoma tumors in mice. ... The slender implants... are 8.5 millimeters in diameter and made of an FDA-approved biodegradable polymer. Ninety percent air, the disks are highly permeable to immune cells and release cytokines, powerful recruiters of immune-system messengers called dendritic cells. These cells enter an implant's pores, where they are exposed to antigens specific to the type of tumor being targeted. The dendritic cells then report to nearby lymph nodes, where they direct the immune system's T cells to hunt down and kill tumor cells.'"