CD4 and lung cancer: Our specific aim was to determine the functionality of total T cells and their subsets, including cytotoxic CD8+ T, CD4+ helper T cells, NK, CD56+T, NKCD4+T and NKCD8+T cells in lung cancer patients before, during and after induction of chemotherapy using a polyclonal activation approach consists of 5 μg/ml Con A and 50ng/ml IL-2.