Expecting that the frequency and number of MDSCs could distinguish between lung cancer patients and healthy controls, immunoglobulin-like transcript 3 (ILT3), which is expressed by MDSCs [43], and arginase-1 (Arg-1) mRNA [44], which is expressed by MDSCs, could also be used as surrogate markers for the frequency of MDSCs in PBMC and as attractive targets for immune intervention. The gene discussed is LILRB4; the disease is lung carcinoma.