Clinical predictive value of naïve and memory T cells in advanced NSCLC

Currently, there is no sensitive prognostic biomarker to screen out benefit patients from the non-benefit population in advanced non-small cell lung cancer patients (aNSCLCs). The 435 aNSCLCs and 278 normal controls (NCs) were recruited. The percentages and absolute counts (AC) of circulating naïve and memory T lymphocytes of CD4⁺ and CD8⁺ T cells (Tn/Tm) were measured by flow cytometry. The percentage of CD4⁺ naïve T (Tn), CD8⁺ Tn, CD8⁺ T memory stem cell (Tscm), and CD8⁺ terminal effector T cell decreased obviously. Still, all AC of Tn/Tm of aNSCLCs was significantly lower compared to NCs. Higher AC and percentage of CD4⁺ Tn, CD8⁺ Tn, and CD4⁺ Tscm showed markedly longer median PFS in aNSCLCs. Statistics demonstrated the AC of CD4⁺ Tn (≥ 3.7 cells/μL) was an independent protective factor for PFS. The analysis of the prognosis of immunotherapy showed the higher AC and percentage of CD4⁺ Tn and CD4⁺ Tscm and higher AC of CD8⁺ Tscm had significantly longer median PFS and the AC of CD4⁺ Tn (≥ 5.5 cells/μL) was an independent protective factor for PFS. Moreover, higher AC and percentages of Tn/Tm suggested higher disease control rate and lower progressive disease rate. The AC of Tn/Tm showed more regular patterns of impairment and was more relative with the disease progression than percentages in aNSCLCs. AC had a better predictive value than percentages in Tn/Tm for PFS. Notably, the AC of CD4⁺ Tn was a potential prognostic biomarker for the PFS and efficacy of immunotherapy.