Human Growth Factor Protein Stops Tumor Growth by Stimulating Killer Cells

Added Immunostimulation Improves Tumor Vaccination

(Mainz, August 2011)

TRON scientists demonstrated how tumor growth may be stopped by injecting a human growth factor protein alongside a RNA-vaccine. Their findings were published in the August issue of the international journal “Cancer Research”.

The so called Flt3-ligand is a human growth factor protein that had previously been investigated as a possible adjuvant in early clinical trials vaccination studies, demonstrating good tolerability but showing little effect. The TRON scientists were therefore surprised to see doubled efficacy in combination with mRNA based tumor vaccinations where it halted tumor growth in mice.  It appears that this specific human growth factor protein stimulates the growth of antigen presenting cells that trigger the production of T-cells and ultimately of killer T-cells, capable of destroying the tumor.

“We knew that in addition to stimulating killer T-cells through vaccination it is important to provide additional, general immunostimulation. It was exciting to see that the Flt3-ligand had such an impact in mRNA vaccines” says Dr. Sebastian Kreiter, co-investigator of the study. “We think our data may pave the way for a clinical application of this recombinant protein in future tumor vaccination protocols.”

Original publication:

Kreiter S, Diken M, Selmi A, Diekmann J, Attig S, Hüsemann Y, Koslowski M, Huber C, Türeci Ö, Sahin U. FLT3 ligand Enhances the Cancer Therapeutic Potency of Naked RNA Vaccines. Cancer Res. 2011 Aug 4.
DOI; PubMed