T-cell immune suppression in patients with hematologic malignancies: clinical implications

CD20+ T cells in monoclonal B cell lymphocytosis and chronic lymphocytic leukemia: frequency, phenotype and association with disease progression

Introduction

In monoclonal B cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL), the expansion of malignant B cells disrupts the normal homeostasis and interactions between B cells and T cells, leading to immune dysregulation. CD20+ T cells are a subpopulation of T cells that appear to be involved in autoimmune diseases and cancer.

Methods

Here, we quantified and phenotypically characterized CD20+ T cells from MBL subjects and CLL patients using flow cytometry and correlated our findings with the B-cell receptor mutational status and other features of the disease.

Results and discussion

CD20+ T cells were more represented within the CD8+ T cell compartment and they showed a predominant memory Tc1 phenotype. CD20+ T cells were less represented in MBL and CLL patients vs healthy controls, particularly among those with unmutated IGVH gene. The expansion of malignant B cells was accompanied by phenotypic and functional changes in CD20+ T cells, including an increase in follicular helper CD4+ CD20+ T cells and CD20+ Tc1 cells, in addition to the expansion of the TCR Vβ 5.1 in CD4+ CD20+ T cells in CLL.

Clinical Characteristics and Outcomes of COVID-19 in 1290 New Cancer Patients: Single-center, Prospective Cohort Study from Iran

OBJECTIVE

To determine the clinical characteristics and outcomes of COVID-19 in a large cohort of new cancer patients referred to an oncology clinic in the north of Iran.

METHODS

During the 20-months COVID-19 pandemic, new cancer patients were followed-up. Demographic, pathologic, and clinical variables were collected for each patient. COVID-19 was confirmed based on a positive polymerase chain reaction test. Analyses were performed using the STATA version 14.0 at a significance level of 0.05.

RESULTS

In this study, 1294 new cancer patients were followed for 24 months (mean age: 58.7 years [range 10 to 95]). During the study period, COVID-19 was diagnosed in 9.4% of the patients with hospitalization rate of 3.4%, an ICU admission rate of 0.7%, and COVID-19 mortality rate of 4.9%. Hematological malignancies (OR_U= 2.6, CI95% 1.28- 5.34), receiving palliative treatments (OR_A=3.03, CI95% 1.6-5.45) and receiving radiotherapy (OR_A=2.07, 1.17-3.65) were the most common predictive factors of COVID infection in cancer patients. Also, the COVID mortality was higher in brain cancer patients (P = 0.07), metastatic disease (P = 0.01) and patients receiving palliative treatments (P = 0.02).

CONCLUSION

In patients suffering from cancer, COVID-19 infection can be predicted by cancer type, palliative care, and radiotherapy in cancer patients. Furthermore, brain cancers, metastasis, and palliative care were all associated with COVID-19 related mortality.

OUP accepted manuscript

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has currently affected >220 million individuals worldwide. The complex interplay of immune dysfunction, active malignancy, the effect of cancer treatment on the immune system and additional comorbidities associated with cancer and COVID-19 all affect the outcomes of COVID-19 in patients with cancer. We have discussed the published findings (through the end of September 2021) on the effects of cancer on the morbidity and mortality of COVID-19, common factors between cancer and COVID-19, the interaction of cancer and COVID-19 treatments, the impact of COVID-19 on cancer clinical services, immune test findings in cancer patients with COVID-19 and the long-term effects of COVID-19 on cancer survivors.

The roles of stem cell memory T cells in hematological malignancies

Adoptive cell therapy (ACT) is rapidly migrating from bench to clinical therapy for hematological malignancies. Recently, a new subtype of memory T cells, stem cell memory T (TSCM) cells, was shown to be one of the most favorable subsets for ACT. TSCM has high self-renewal capacity and is associated with superior T cell engraftment, persistence, and antitumor immunity. In this review, we focused on the characteristics of antigen-specific TSCM cells and discussed their potential for immunotherapy targeting hematological malignancies.

Enhancement of the TCRζ expression, polyclonal expansion, and activation of t cells from patients with acute myeloid leukemia after IL-2, IL-7, and IL-12 induction

Defective T cell receptor (TCR) signaling resulting in lower T cell function plays a crucial role in the pathogenesis of T cell immunodeficiency in leukemia. Previous studies have indicated that lower TCRζ levels are a common characteristic of patients with leukemia, and upregulating TCRζ could partially recover T cell function. In this study, we characterized the effect of the stimulating factor induction on the TCRζ, Zap-70, and FcɛRIγ levels, IFN-γ secretion, and the distribution and clonal expansion of TCR Vβ subfamilies in CD3(+) T cells sorted from peripheral blood from acute myeloid leukemia (AML) patients. The induction included single stimulating factor or a combination with different cytokines (IL-2, IL-7, IL-2+IL-7, IL-7+IL-12, CD3, CD3+CD28 antibody, CD3+CD28 antibody+IL-2, and CD3+CD28 antibody+IL-7) at 72 h. The results showed that increased TCRζ and Zap-70 levels with deceased FcɛRIγ in T cells after induction, and different responses to cytokine in T cell from different cases may indicate the heterogeneity of T cells and different immune statuses in different AML cases. Increased IFN-γ levels in T cells from AML patients were detected after induction in the IL-12+IL-7, CD3+CD28+IL-2, and CD3+CD28+IL-7 groups. Moreover, the number of TCR Vβ subfamily T cells expressed was increased; however, all of the TCR Vβ subfamily T cells in the AML patients could not be completely recovered after induction. In conclusion, the cytotoxicity and activation function of T cells could be enhanced after induction by different stimuli accompanied by an increase in TCRζ and Zap-70 and recovery of the TCR Vβ repertoire in AML patients.