Peripheral T cells of patients with B cell non-Hodgkin's lymphoma show a shift in their memory status

Implication of immune cell signature of tumor microenvironment in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a genetically heterogeneous disease with complex tumor microenvironment (TME) alterations. However, immune cell signatures of TME and their prognostic value remain unclear in DLBCL. We aimed to identify high-risk DLBCL with specific immune cell signatures in TME. Clinical and gene expression data of DLBCL patients were obtained from previously reported retrospective datasets in Gene Expression Omnibus (GSE10846⁶ and GSE53786¹⁶ ) and a multi-center prospective clinical trial NHL001 (NCT01852435). Patients treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen (n = 159) from GSE10846 were referred as training cohort for CHOP regimen, while patients treated with rituximab-CHOP (R-CHOP) regimen (n = 192) from GSE10846 as training cohort for R-CHOP regimen. Patients from NHL001 (n = 68) and GSE53786 (n = 57) were referred as validation cohorts for R-CHOP regimen. CIBERSORT was applied to estimate the relative proportions of 22 subtype of immune cells. We established a prognostic model for model for R-CHOP regimen included Age, performance status, lactate dehydrogenase, T cells follicular helper and macrophages M0, defining a low-risk group with 2-years OS of 92.9% and a high-risk group with 2-years OS of 52.5% (HR 6.57 [3.27-13.18], p < 0.0001). Immune cell signatures could be used as prognostic markers and provided further insights for individualized immunotherapeutic strategies in DLBCL.

Peripheral blood T cell alterations in newly diagnosed diffuse large B cell lymphoma patients and their long-term dynamics upon rituximab-based chemoimmunotherapy

The importance of T cell-dependent immune responses in achieving long-term cure of chemoimmunotherapy-treated cancer patients is underscored by the recently described "vaccinal effect" exerted by therapeutic mAbs. In accordance, pre- and post-therapy peripheral blood lymphopenia represents a well-established negative prognostic factor in DLBCL. We analyzed the phenotypic and functional (IFNγ production, and Granzyme B (GrzB) cytotoxic granule marker expression) profile of peripheral blood T lymphocyte subsets ("conventional" CD4+ and CD8+, FOXP3+CD25bright Treg, and "innate-like" CD56+) in DLBCL patients at diagnosis, and assessed the long-term impact of R-CHOP chemoimmunotherapy, in a prospective study. At diagnosis, DLBCL patients showed lower lymphocyte counts, due to selective decrement of CD4+ T (including Treg) and B lymphocytes. While all T cell subsets transiently decreased during therapy, CD4+ T cell and Treg remained significantly lower than controls, up to 1 year after R-CHOP. Phenotypically skewed profile of CD4+ and CD8+ T cell subsets associated with higher frequencies of IFNγ+ and GrzB+ cells at diagnosis, that transiently decreased during therapy, and re-attained persistently elevated levels, till up to 1 year after therapy. Differently, the pre-therapy elevated levels of circulating monocytes, and of plasma IL-6 and IL-10 rapidly normalized upon R-CHOP. In sum, we describe a quantitatively and functionally altered status of the peripheral blood T cell compartment in DLBCL patients at diagnosis, that persists long-term after tumor eradication, and it is only transiently perturbed by R-CHOP chemoimmunotherapy. Moreover, data suggest the association of selected T cell functional features with DLBCL phenotype, and with therapy outcome.

Immune modulation effects of concomitant temozolomide and radiation therapy on peripheral blood mononuclear cells in patients with glioblastoma multiforme

Concomitant radiation therapy (RT) and temozolomide (TMZ) therapy after surgery is the standard treatment for glioblastoma multiforme (GBM). Radiation and chemotherapy can affect the immune system with implications on subsequent immune therapy. Therefore, we examined the phenotype and function of peripheral blood mononuclear cells in 25 patients with GBM prior to and 4 weeks after treatment with RT-TMZ using multicolor flow cytometry, as well as in vitro CD4(+) regulatory T cell (T(reg)) suppressor and dendritic cell maturation assays. RT-TMZ induced significant lymphopenia, with a decrease in total CD4(+) T cells, but did not significantly change monocyte counts. The proportion of functional T(reg) cells increased after treatment, whereas their absolute numbers remained stable. There was also a measurable decrease in the proportion of CD8(+)CD56(+) and absolute number of CD3(-)CD56(+) effector cells. Posttherapy monocytes retained the ability to mature into dendritic cells. Treatment with RT-TMZ is associated with changes in regulatory and effector peripheral blood mononuclear cells that tilt the balance towards an immune suppressive state. This shift can affect the outcome of immune therapy following RT-TMZ treatment and should be considered in the design of future combination therapy regimens.

Difference in the relative distribution of CD4+ T-cell subsets in B-CLL with mutated and unmutated immunoglobulin (Ig) VH genes: implication for the course of disease

B-cell chronic lymphocytic leukemia (B-CLL) is a clinically heterogeneous disease in which the clinical course is influenced by the presence or absence of immunoglobulin (Ig) variable heavy chain (VH) gene mutations. The poor clinical outcome of the subgroup with unmutated Ig VH genes has been linked to the persistent ability of the B-cell receptor in tumor cells from these cases to respond to antigen. As B-cell receptor signaling generally relies on T-cell help, we hypothesized that the course of B-CLL might not only be influenced by the Ig VH mutational status but also by the activation/differentiation status of T cells. We assessed the relative distribution of naive and memory T-cell subsets in peripheral blood from patients with mutated (M-CLL, n=71) and unmutated Ig VH genes (UM-CLL, n=42) and correlated it with the course of disease. We also compared the prosurvival potential of naive and memory T cells cocultured with B-CLL cells in vitro. A significant increase in relative numbers of central and effector memory T cells was observed in the CD4 T-cell pool from UM-CLL as compared with M-CLL cases and was associated with high Rai stage, progressive disease and shorter treatment-free survival (TFS). In a multivariate analysis, the relative number of CD4 central and effector memory T cells remained a significant prognostic parameter for TFS after correction for CD38 expression, Ig VH status, genomic aberrations, and Rai stage. The inverse correlation of memory CD4 T cells with TFS might be explained by their potential to support survival of B-CLL cells.