T-cell subsets in lymph nodes identify a subgroup of follicular lymphoma patients with favorable outcome

Senescent T Cells in Age-Related Diseases

Age-induced alterations in human immunity are often considered deleterious and are referred to as immunosenescence. The immune system monitors the number of senescent cells in the body, while immunosenescence may represent the initiation of systemic aging. Immune cells, particularly T cells, are the most impacted and involved in age-related immune function deterioration, making older individuals more prone to different age-related diseases. T-cell senescence can impact the effectiveness of immunotherapies that rely on the immune system's function, including vaccines and adoptive T-cell therapies. The research and practice of using senescent T cells as therapeutic targets to intervene in age-related diseases are in their nascent stages. Therefore, in this review, we summarize recent related literature to investigate the characteristics of senescent T cells as well as their formation mechanisms, relationship with various aging-related diseases, and means of intervention. The primary objective of this article is to explore the prospects and possibilities of therapeutically targeting senescent T cells, serving as a valuable resource for the development of immunotherapy and treatment of age-related diseases.

Implications of Senescent T Cells for Cancer Immunotherapy

T-cell senescence is thought to result from the age-related loss of the ability to mount effective responses to pathogens and tumor cells. In addition to aging, T-cell senescence is caused by repeated antigenic stimulation and chronic inflammation. Moreover, we demonstrated that T-cell senescence was induced by treatment with DNA-damaging chemotherapeutic agents. The characteristics of therapy-induced senescent T (TIS-T) cells and general senescent T cells are largely similar. Senescent T cells demonstrate an increase in the senescence-associated beta-galactosidase-positive population, cell cycle arrest, secretion of senescence-associated secretory phenotypic factors, and metabolic reprogramming. Furthermore, senescent T cells downregulate the expression of the co-stimulatory molecules CD27 and CD28 and upregulate natural killer cell-related molecules. Moreover, TIS-T cells showed increased PD-1 expression. However, the loss of proliferative capacity and decreased expression of co-stimulatory molecules associated with T-cell senescence cause a decrease in T-cell immunocompetence. In this review, we discuss the characteristics of senescent T-cells, including therapy-induced senescent T cells.

Advances in Monitoring and Prognostication for Lymphoma by Flow Cytometry

Flow cytometry (FC) is a well-established method important in the diagnosis and subclassification of lymphoma. In this article, the role of FC in lymphoma prognostication will be explored, and the clinical role for FC minimal/measurable residual disease testing as a monitoring tool for mature lymphoma will be introduced. Potential pitfalls of monitoring for residual/recurrent disease following immunotherapy will be presented.

Senescent T cells: a potential biomarker and target for cancer therapy

The failure of T cells to eradicate tumour cells in the tumour microenvironment is mainly due to the dysfunction of T cells. Senescent T cells, with defects in proliferation and effector functions, accumulate in ageing, chronic viral infections, and autoimmune disorders where antigen stimulation persists. Increasing evidence suggests that inducing T cell senescence is a key strategy used by malignant tumours to evade immune surveillance. In this review, we summarize the general features, functional regulation, and signalling network of senescent T cells in tumour development and highlight their potential as prognostic biomarkers in multiple cancer treatments, including chemotherapy, radiotherapy, and immunotherapy. Moreover, we discuss possible therapeutic strategies for preventing or rejuvenating senescence in tumour-specific T cells. Understanding these critical issues may provide novel strategies to enhance cancer immunotherapy.