In vitro and in vivo effect of PD‐1/PD‐L1 blockade on microglia/macrophage activation and T cell subset balance in cryptococcal meningitis

2017 ◽  
Vol 119 (4) ◽  
pp. 3044-3057 ◽  
Author(s):  
Yuan‐Mei Che ◽  
Yi Zhang ◽  
Ming Li ◽  
Xiao‐Peng Li ◽  
Lun‐Li Zhang
Author(s):  
Takayoshi Yamauchi ◽  
Toshifumi Hoki ◽  
Takaaki Oba ◽  
Kristopher Attwood ◽  
Xuefang Cao ◽  
...  

AbstractThe use of tumor mutation-derived neoantigen represents a promising approach for cancer vaccines. Preclinical and early-phase human clinical studies have shown the successful induction of tumor neoepitope-directed responses; however, overall clinical efficacy of neoantigen vaccines has been limited. One major obstacle of this strategy is the prevailing lack of sufficient understanding of the mechanism underlying the generation of neoantigen-specific CD8+ T cells. Here, we report a correlation between antitumor efficacy of neoantigen/toll-like receptor 3 (TLR3)/CD40 vaccination and the generation of antigen-specific CD8+ T cells expressing CX3C chemokine receptor 1 (CX3CR1) in a preclinical model. Mechanistic studies using mixed bone marrow chimeras identified that CD40 and CD80/86, but not CD70 signaling in Batf3-dependent conventional type 1 dendritic cells (cDC1s) is required for antitumor efficacy of neoantigen vaccine and generation of neoantigen-specific CX3CR1+ CD8+ T cells. Although CX3CR1+ CD8+ T cells exhibited robust in vitro effector function, depletion of this subset did not alter the antitumor efficacy of neoantigen/TLR3/CD40 agonists vaccination, suggesting that the expanded CX3CR1+ CD8+ T cell subset represents the post-differentiated in vivo effective CX3CR1-negative CD8+ T cell subset. Taken together, our results reveal a critical role of CD40 and CD80/86 signaling in cDC1s in antitumor efficacy of neoantigen-based therapeutic vaccines, and implicate the potential utility of CX3CR1 as a circulating predictive T-cell biomarker in vaccine therapy.


2017 ◽  
Vol 4 (3) ◽  
pp. e340 ◽  
Author(s):  
Mahtab Ghadiri ◽  
Ayman Rezk ◽  
Rui Li ◽  
Ashley Evans ◽  
Felix Luessi ◽  
...  

Objective:To examine the mechanism underlying the preferential CD8+ vs CD4+ T-cell lymphopenia induced by dimethyl fumarate (DMF) treatment of MS.Methods:Total lymphocyte counts and comprehensive T-cell subset analyses were performed in high-quality samples obtained from patients with MS prior to and serially following DMF treatment initiation. Random coefficient mixed-effects analysis was used to model the trajectory of T-cell subset losses in vivo. Survival and apoptosis of distinct T-cell subsets were assessed following in vitro exposure to DMF.Results:Best-fit modeling indicated that the DMF-induced preferential reductions in CD8+ vs CD4+ T-cell counts nonetheless followed similar depletion kinetics, suggesting a similar rather than distinct mechanism involved in losses of both the CD8+ and CD4+ T cells. In vitro, DMF exposure resulted in dose-dependent reductions in T-cell survival, which were found to reflect apoptotic cell death. This DMF-induced apoptosis was greater for CD8+ vs CD4+, as well as for memory vs naive, and conventional vs regulatory T-cell subsets, a pattern which mirrored preferential T-cell subset losses that we observed during in vivo treatment of patients.Conclusions:Differential apoptosis mediated by DMF may underlie the preferential lymphopenia of distinct T-cell subsets, including CD8+ and memory T-cell subsets, seen in treated patients with MS. This differential susceptibility of distinct T-cell subsets to DMF-induced apoptosis may contribute to both the safety and efficacy profiles of DMF in patients with MS.


Blood ◽  
2012 ◽  
Vol 119 (11) ◽  
pp. 2443-2451 ◽  
Author(s):  
Tatiana Akimova ◽  
Ulf H. Beier ◽  
Yujie Liu ◽  
Liqing Wang ◽  
Wayne W. Hancock

Abstract Clinical and experimental studies show that inhibition of histone/protein deacetylases (HDAC) can have important anti-neoplastic effects through cytotoxic and proapoptotic mechanisms. There are also increasing data from nononcologic settings that HDAC inhibitors (HDACi) can exhibit useful anti-inflammatory effects in vitro and in vivo, unrelated to cytotoxicity or apoptosis. These effects can be cell-, tissue-, or context-dependent and can involve modulation of specific inflammatory signaling pathways as well as epigenetic mechanisms. We review recent advances in the understanding of how HDACi alter immune and inflammatory processes, with a particular focus on the effects of HDACi on T-cell biology, including the activation and functions of conventional T cells and the unique T-cell subset, composed of Foxp3+ T-regulatory cells. Although studies are still needed to tease out details of the various biologic roles of individual HDAC isoforms and their corresponding selective inhibitors, the anti-inflammatory effects of HDACi are already promising and may lead to new therapeutic avenues in transplantation and autoimmune diseases.


2019 ◽  
Vol 10 ◽  
Author(s):  
Maria Kuznetsova ◽  
Julia Lopatnikova ◽  
Julia Shevchenko ◽  
Alexander Silkov ◽  
Amir Maksyutov ◽  
...  

1997 ◽  
Vol 186 (9) ◽  
pp. 1407-1418 ◽  
Author(s):  
Dörte Hamann ◽  
Paul A. Baars ◽  
Martin H.G. Rep ◽  
Berend Hooibrink ◽  
Susana R. Kerkhof-Garde ◽  
...  

Human CD8+ memory- and effector-type T cells are poorly defined. We show here that, next to a naive compartment, two discrete primed subpopulations can be found within the circulating human CD8+ T cell subset. First, CD45RA−CD45R0+ cells are reminiscent of memory-type T cells in that they express elevated levels of CD95 (Fas) and the integrin family members CD11a, CD18, CD29, CD49d, and CD49e, compared to naive CD8+ T cells, and are able to secrete not only interleukin (IL) 2 but also interferon γ, tumor necrosis factor α, and IL-4. This subset does not exert cytolytic activity without prior in vitro stimulation but does contain virus-specific cytotoxic T lymphocyte (CTL) precursors. A second primed population is characterized by CD45RA expression with concomitant absence of expression of the costimulatory molecules CD27 and CD28. The CD8+CD45RA+CD27− population contains T cells expressing high levels of CD11a, CD11b, CD18, and CD49d, whereas CD62L (L-selectin) is not expressed. These T cells do not secrete IL-2 or -4 but can produce IFN-γ and TNF-α. In accordance with this finding, cells contained within this subpopulation depend for proliferation on exogenous growth factors such as IL-2 and -15. Interestingly, CD8+CD45RA+CD27− cells parallel effector CTLs, as they abundantly express Fas-ligand mRNA, contain perforin and granzyme B, and have high cytolytic activity without in vitro prestimulation. Based on both phenotypic and functional properties, we conclude that memory- and effector-type T cells can be separated as distinct entities within the human CD8+ T cell subset.


1980 ◽  
Vol 152 (4) ◽  
pp. 823-841 ◽  
Author(s):  
E Fernandez-Cruz ◽  
B A Woda ◽  
J D Feldman

Established subcutaneous Moloney sarcomas (MST-1) of large size and long duration were eliminated from syngeneic rats by intravenous infusion of varying numbers of specific syngeneic effector T lymphocytes. Spleen cells from BN rats in which tumor had regressed were cultured in an in vitro mixed lymphocyte tumor cell culture (MLTC) to augment cytotoxicity of effector cells. In the MLTC a T cell subset was expanded in response to MST-1 antigens and transformed into blast elements. With these changes, there was an increase in the W3/25 antigen on the T cell surface, a decrease of W3/13 antigen, and an increase in the number of T cells with Ia antigens. The subset associated with elimination of established tumors was a blast T cell W3/25+, W3/13+, as detected by monoclonal antibodies to rat T antigens. The W3/25+ subset was poorly cytotoxic in vitro for MST-1 and apparently functioned in vivo as an amplifier or helper cell in the tumor-bearing host. The W3/25- population was a melange of cells that included (W3/13+, W3/25-) T cells, null cells, Ig+ cells, and macrophages, and was associated with enhancement of tumor in vivo, suggesting the presence of suppressor cells.


2004 ◽  
Vol 173 (3) ◽  
pp. 1787-1794 ◽  
Author(s):  
Diana L. Wallace ◽  
Yan Zhang ◽  
Hala Ghattas ◽  
Andrew Worth ◽  
Andrew Irvine ◽  
...  

1996 ◽  
Vol 60 (2) ◽  
pp. 221-229 ◽  
Author(s):  
Henri C. van der Heyde ◽  
M. Merle Elloso ◽  
Wun-Ling Chang ◽  
Barbara J. Pepper ◽  
Joan Batchelder ◽  
...  

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