Therefore, we analysed the 5 gene panel (CD247, LCK, LAT, VAV2 and VAV3) by applying PCR to the COPD and S pulmonary samples; CD247 (fold change −1.79, relative reduction 46% p = 0.006) and LCK (fold change −1.77, relative reduction 44% p = 0.03) were both expressed at significantly lower levels in COPD compared to S pulmonary CD8 cells (Figure 4). Here, LCK is linked to chronic obstructive pulmonary disease.