Dendritic cells (DCs) are potent antigen-presenting cells (APCs) that are essential in mediating the body's natural and adaptive immune responses. The body can regulate the function of DCs in various ways to enhance their antitumor effects. In the tumour microenvironment (TME), antigen-specific T cell responses are initiated through DC processing and delivery of tumour-associated antigens (TAAs); conversely, tumour cells inhibit DC recruitment by releasing metabolites, cytokines and other regulatory TME and function. Different subpopulations of DCs exist in tumour tissues, and their functions vary. Insight into DC subgroups in TME allows assessment of the effectiveness of tumour immunotherapy. Astragalus polysaccharide (APS) is the main component of the Chinese herb Astragalus membranaceus. The study found that the antitumor effects of APS are closely related to DCs. APS can promote the expression of surface molecules CD80 and CD86, promote the maturation of DCs, and activate CTL to exert antitumor effects. We reviewed the application of DCs in tumor immunotherapy and the mechanism of modulation of DCs by Astragalus polysaccharide to provide new directions and strategies for tumor therapy and new drug development.

T cells play an important role in cancer, and energy metabolism can determine both the proliferation and differentiation of T cells. The inhibition of immune checkpoint molecules programmed cell death protein 1 (PD‑1) and cytotoxic T‑lymphocyte associated protein 4 (CTLA‑4) are a promising cancer treatment. In recent years, research on CD28 has increased. Although numerous reports involve CD28 and its downstream PI3K/AKT/mTOR signaling mechanisms in T cell metabolism, they have not yet been elucidated. A literature search strategy was used for the databases PubMed, Scopus, Web of Science and Cochrane Library to ensure broad coverage of medical and scientific literature, using a combination of keywords including, but not limited to, ‘lung cancer’ and ‘immunotherapy’. Therefore, the present study reviewed the interaction and clinical application of the PD‑1/CTLA‑4/CD28 and PI3K/AKT/mTOR pathways in T cells, aiming to provide a theoretical basis for immunotherapy in clinical cancer patients.

Immune function strongly influences the outcome of patients with non-small cell lung cancer (NSCLC). It's vital to understand the immune state of patients through detecting the percentage and number of lymphocyte subsets accurately, and helpful to evaluate conditions of prognosis and adjust treatment for patients. We conducted a retrospective cohort study in First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China. The absolute counts and percentages of CD3+, CD3 + CD4+, CD3 + CD8+, B and NK cells were determined by single platform technologies. 172 patients received treatment including surgery or chemotherapy after surgery. The factors affecting disease progression were analyzed by Binary Logistic regression. Progression free survival (PFS) calculating survivals were with the method of Kaplan-Meier. The log-rank test and cox's proportional hazard regression (enter method) were used for univariable and multivariable analyses respectively. Relative to normal controls, patients with NSCLC at different stages showed decreased absolute lymphocyte count obviously, rather than lymphocyte percentages. Different treatments had unlike influence on the homeostasis of lymphocytes and the effects last for a long time. Logistic regression showed CD3 + CD4+ and CD3 + CD8+ could contribute to favorable prognosis. Multivariate analysis of prognostic factors of PFS showed CD3 + CD4+ cell was independent factor for predicting PFS. The absolute count of CD3+, CD3 + CD4+, CD3 + CD8+, B and NK cells were better indication of the patient's immune state than percentages of each lymphocyte subsets. Immune function was impaired in patients with non-small cell lung. The high level of baseline absolute CD3 + CD4+ cells count contributed to longer progression free survival. Chinese Clinic Trial Registry number: ChiCTR-IOR-17014139; Registry date: 2017/12/25.

Naïve T and T memory cell subsets are closely related to immune response and can provide important information for the diagnosis and treatment of immunological and hematological disorders. Lymphocyte compartment undergoes dramatic changes during adulthood; age-related reference values derived from healthy individuals are crucial. However, extensively detailed reference values of peripheral blood lymphocytes in the whole spectrum of adulthood detected by multi-color flow cytometry on a single platform are rare. Three hundred and nine healthy adult volunteers were recruited from Tianjin in China. The absolute counts and percentages of CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, naïve T cells (Tn), T memory stem cells (Tscm), central memory T cells (Tcm), effector memory T cells (Tem), and terminal effector T cells (Tte) were detected by flow cytometry with single platform technologies. Reference range of absolute counts and percentage of T lymphocyte subsets were formulated by different age and gender. The results showed that Tn and Tscm cells, which had stem cell properties, decreased with aging; while, Tcm and Tem increased with aging, which increased from 18 to 64 years old but presented no significant change over the 65 years old. Gender had an influence on the fluctuation of lymphocyte subsets, the absolute count of CD3+CD8+, CD8+Tcm, CD8+Tem in males were higher than those in females. The reference values of percentages and absolute numbers of naïve T and T memory cell subsets can help doctors to understand the immune state of patients and evaluate conditions of prognosis then adjust the treatment for patients. (Chinese Clinic Trial Registry number: ChiCTR-IOR-17014139.)

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.

Background. As the number and proportion of lymphocyte subsets are an important indicator of the immune function, an in depth understanding of the immune function of patients with malignant tumor has important clinical values for the treatment, prognosis, and evaluation of the disease. This retrospective study was to evaluate the clinical value of the absolute counts of lymphocyte subsets as potential blood biomarkers for progression and prognosis in breast cancer patients. Methods. A total of 237 BC patients and 55 age‐matched female normal healthy donors were included in this study. Flow cytometry was used to determine the absolute counts and the percentages of CD3⁺, CD4⁺, CD8⁺, B, and NK cells. The receiver operating characteristic curve (ROC) was used to evaluate the accuracy of absolute count of lymphocyte subsets in the curative efficacy assessment. The clinicopathological parameters influencing the disease progression were determined by Cox proportional hazards regression. Progression‐free survival (PFS) was estimated using the Kaplan–Meier method with the log‐rank test. Results: Compared with the healthy donors, the absolute counts of lymphocyte subsets in patients decreased significantly. ROC analysis showed that the area under the curve of the CD4⁺ absolute count was 90% (95% confidence interval 0.859–0.940), and the sensitivity and specificity were 80.9% and 85.3%, respectively. The analysis of Cox regression showed that the cutoff value of the CD4⁺ absolute count ≥451 cells/μL might be a favorable prognostic factor. Multivariate analysis of prognostic factors of PFS showed that the CD4⁺ and CD8⁺ absolute count were independent factors for predicting PFS. Conclusions. The remarkably impaired absolute counts of the CD3⁺, CD4⁺, CD8⁺, B, and NK cells in patients with breast cancer can be used as potential susceptible biomarkers to evaluate the patient’s immune status. The higher level of CD4⁺ and CD8⁺ absolute counts probably contributed to the longer PFS and favorable outcome of BC patients.