Lymph vessels grow as wounds heal and cancers spread — a process that can be imaged in living animals, researchers demonstrate in mice.

Lymph vessels often sprout at sites of inflammation, and their growth has been linked to tumour metastasis. Sagrario Ortega at the Spanish National Cancer Research Centre in Madrid and her colleagues genetically engineered a mouse to express a luminescent protein under the control of the gene Vegfr3, a lymphatic marker.

The team imaged live mice, tracking vessel growth during embryo development, wound healing and inflammation. They also watched as lymph vessels grew at the edge of melanoma tumours and in lymph nodes infiltrated by the cancer. This vessel growth may aid the spread of cancer to distant organs, the authors say.

Proc. Natl Acad. Sci. USA http://dx.doi.org/10.1073/pnas.1115542109 (2012)