Peripheral blood lymphocyte subsets of newly diagnosed DLBCL patients and their dynamic changes with rituximab based immunochemotherapy

PD-L1 Is Involved in the Development of Non-Hodgkin's Lymphoma by Mediating Circulating Lymphocyte Apoptosis

Lymphocyte apoptosis plays a crucial role in tumor-induced immunosuppression. Programmed death ligand-1 (PD-L1) blocks lymphocyte activation via its receptor, PD-1. However, PD-L1/PD-1 expression and its role in enhancing immune suppression in non-Hodgkin lymphoma (NHL) have not been identified. The purpose of the study was to assess PD-L1/PD-1 expression in circulating lymphocytes in NHL and its role in immunosuppression. Twenty newly diagnosed NHL patients and twenty normal volunteers were enrolled in the study. PD-L1/PD-1 expression in circulating lymphocytes and the apoptosis of lymphocyte subsets were assessed using flow cytometry. The findings revealed that the PD-L1 expression in circulating CD3+, CD3+CD4+, CD3+CD8+, and CD20+ lymphocytes were dramatically upregulated in NHL patients (p < 0.001), whereas peripheral lymphocytes expressed low levels of PD-1. Compared with normal volunteers, a significant increase in lymphocyte apoptosis was revealed by annexin-V binding on T and B lymphocytes (p < 0.001). Peripheral lymphocytes expressing PD-L1 were four times more vulnerable to apoptosis than those expressing PD-1. Our findings imply that PD-L1 upregulation contributes to NHL development by promoting circulating lymphocyte apoptosis. This research adds to our understanding of the function of the PD-L1/PD-1 pathway in tumor evasion, establishing a novel therapeutic target in NHL. The results offer additional evidence for the immunomodulatory role of PD-L1 in circulating lymphocytes, providing a rationale for further investigations into immunological dysfunctions resulting from NHL. PD-L1+ lymphocytes could be employed as a biomarker to assess the effectiveness of immune systems and predict illness in patients with NHL.

Systemic immune inflammation index, ratio of lymphocytes to monocytes, lactate dehydrogenase and prognosis of diffuse large B-cell lymphoma patients

BACKGROUND

In malignant tumors, inflammation plays a vital role in the development, invasion, and metastasis of cancer cells. Diffuse large B-cell lymphoma (DLBCL), the most common malignant proliferative disease of the lymphatic system, is commonly associated with inflammation. The international prognostic index (IPI), which includes age, lactate dehydrogenase (LDH), number of extranodal lesions, Ann Arbor score, and Eastern Cooperative Oncology Group (ECOG) score, can evaluate the prognosis of DLBCL. However, its use in accurately identifying high-risk patients and guiding treatment is poor. Therefore, it is important to find novel immune markers in predicting the prognosis of DLBCL patients.

AIM

To determine the association between the systemic immune inflammation index (SII), ratio of lymphocytes to monocytes (LMR), ratio of LMR to LDH (LMR/LDH), and prognosis of patients with DLBCL.

METHODS

A total of 68 patients diagnosed with DLBCL, treated in our hospital between January 2016 and January 2020, were included. χ² test, Pearson’s R correlation, Kaplan Meier curves, and Cox proportional risk regression analysis were used. The differences in the SII, LMR, and LMR/LDH among patients with different clinicopathological features were analyzed. The differences in progression-free survival time among patients with different SII, LMR, and LMR/LDH expressions and influencing factors affecting the prognosis of DLBCL patients, were also analyzed.

RESULTS

The LMR and LMR/LDH in patients with Ann Arbor stage III–IV, ECOG score ≥ 2, and SII, IPI score 2–5 were significantly higher than those of patients with Ann Arbor stage I-II and ECOG score < 2 (P < 0.05). Patients with high SII, LMR, and LMR/LDH had progression-free survival times of 34 mo (95%CI: 32.52–38.50), 35 mo (95%CI: 33.42–36.58) and 35 mo (95%CI: 33.49–36.51), respectively, which were significantly lower than those with low SII, LMR, and LMR/LDH (P < 0.05); the SII, LMR, and LMR/LDH were positively correlated (P < 0.05). Cox proportional risk regression analysis showed that the SII, LMR, and LMR/LDH were influencing factors for the prognosis of DLBCL patients (hazard ratio = 1.143, 1.665, and 1.704, respectively; P < 0.05).

CONCLUSION

The SII, LMR, and LMR/LDH are related to the clinicopathological features of DLCBL, and they also influence the prognosis of patients with the disease.

Dynamic changes in peripheral blood lymphocyte subset counts and functions in patients with diffuse large B cell lymphoma during chemotherapy

Background

This study aimed to analyze the lymphocyte subsets, their activities and their dynamic changes during immunochemotherapy in patients newly diagnosed with diffuse large B cell lymphoma (DLBCL).

Methods

Patients with DLBCL (n = 33) were included in the present study. Their peripheral lymphocyte subsets, phenotypes and functions were detected using flow cytometry. The dynamic results of lymphocyte activities were available for 18 patients.

Results

Compared with healthy controls (HCs), the counts of CD3⁺, CD4⁺, and CD8⁺ T cells as well as those NK cells decreased in patients newly diagnosed with DLBCL, mainly attributed to patients with high risk of prognosis assessed by International Prognostic Index (IPI) score. Lymphocyte counts didn’t present significant difference between high risk (IPI scores 3–5) and low risk patients (IPI scores 0–2), but CD4⁺ T cells and CD8⁺ T cells expressed higher levels of CD28 and HLA-DR, respectively, in patients with IPI score ranging from 3 to 5. Patients at high risk harbored higher percentage of regulatory T cells (Tregs), and their CD4⁺ and CD8⁺ T cells produced lower levels of IFN-γ, reflecting an impaired cellular immune response. The dynamic changes of lymphocyte numbers and functions during treatment were further investigated. Total counts of CD3⁺, CD4⁺, CD8⁺ T and NK cells progressively decreased because of the cytotoxicity of chemotherapy and then gradually recovered after six cycles treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone, R-CHOP). The functions of CD4⁺ and CD8⁺ T cells recovered by the end of two cycles R-CHOP treatment, although NK cell function was not significantly affected throughout treatment. These results suggest that the counts and functions of lymphocytes are significantly decreased in patients with DLBCL, particularly those of CD4⁺ and CD8⁺ T cells.

Conclusions

The absolute counts and functions of CD4⁺, CD8⁺ T cells, which were significantly lower in patients with DLBCL, gradually recovered after effective treatment. Therefore, combined detection of T cell counts and functions are critically important for administering effective personalized immunotherapy as well as for identifying new prognostic markers or DLBCL.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01978-w.