Reportage in a laboratory which develops therapeutic vaccinations to treat small-cell lung cancer, using optimised cryptic peptide technology. These vaccinations are intended to treat cancer by stimulating the immune system so it can recognise and attack cancer cells, without harming normal cells. They target over-expressed antigens present in tumourous cells (universal tumour antigens). The lab grows T lymphocytes and dendritic cells. Dendritic cells are filled with optimised cryptic peptides (antigens), then put into contact with T cells so they become responsive to the antigen. The activated T lymphocytes are then able to target the cancer cells. Colouring T lymphocytes before the cell count.