scholarly journals Myeloid-Derived Suppressor Cells: Implications in the Resistance of Malignant Tumors to T Cell-Based Immunotherapy

Author(s):  
Houhui Shi ◽  
Kai Li ◽  
Yanghong Ni ◽  
Xiao Liang ◽  
Xia Zhao

T lymphocytes function as major players in antigen-mediated cytotoxicity and have become powerful tools for exploiting the immune system in tumor elimination. Several types of T cell-based immunotherapies have been prescribed to cancer patients with durable immunological response. Such strategies include immune checkpoint inhibitors, adoptive T cell therapy, cancer vaccines, oncolytic virus, and modulatory cytokines. However, the majority of cancer patients still failed to take the advantage of these kinds of treatments. Currently, extensive attempts are being made to uncover the potential mechanism of immunotherapy resistance, and myeloid-derived suppressor cells (MDSCs) have been identified as one of vital interpretable factors. Here, we discuss the immunosuppressive mechanism of MDSCs and their contributions to failures of T cell-based immunotherapy. Additionally, we summarize combination therapies to ameliorate the efficacy of T cell-based immunotherapy.

2021 ◽  
Vol 4 (2) ◽  
pp. 25-38
Author(s):  
O.Yu. Nikolaeva ◽  
R.V. Liubota ◽  
O.S. Zotov ◽  
R.I. Vereshchako

Cancer immunotherapy is a relatively new and pro­mising method of treating neoplasms. Understanding the antigen-directed cytotoxicity of T-lymphocytes has become one of the central directions in involving the immune system in the fight against cancer. Basic research in this area has led to the invention of checkpoint inhibitors, adoptive T-cell therapy, and cancer vaccines. Cytokines can enhance the action of T-lymphocytes for their ability to directly stimulate effector and stromal cells in tumor focus and enhance recognition of tumor cells by cytotoxic effector cells. They were the first in cancer immunotherapy and remain relevant to this day. Today, immunotherapy is an effective treatment for most malignant tumors, including melanoma, non-small cell lung cancer, liver, stomach, bladder, cervical cancer, some types of breast cancer, lymphoma, etc. However, immunotherapy of some malignant tumors is ineffective, therefore, the development of new and improvement of existing immunotherapy agents is actively underway, and there is a hope that the indications for its use will expand. For this purpose, this review discusses the principles of action of various classes of immunotherapeutic anticancer agents, namely cytokines, immune checkpoint inhibitors, and adaptive T-cell therapy. The work highlights their indications, efficacy and toxicity from the use of each class of drugs, as well as the prospects for the development of immunotherapeutic anticancer drugs.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4653-4653
Author(s):  
James E Talmadge ◽  
Elizabeth Reed ◽  
Kenneth Cowan ◽  
Dmitry Gabrilovich ◽  
Phyllis Warkentin ◽  
...  

Abstract Myeloid derived suppressor cells (MDSCs) have been reported to be expanded in cancer patients, following growth factor administration and after chemotherapy. These cells have been associated with a loss of T-cell number and function and provide one mechanism of immune evasion. We examined the effect of dose dense chemotherapy on immune phenotypes and function in patients with breast cancers 4 cms or larger and/or four or more involved nodes. The adjuvant therapy was dose-dense doxorubicin, cyclophosphamide (AC) followed by paclitaxel (P), then 33 doses of radiation (R). Blood samples were obtained and studied prior to therapy, 1 week post AC and 1, 15 and 21 weeks post P and then 3, 6 and 12 months later. Flow cytometric analyses of cellular phenotypes were done on these blood specimens and compared to the levels prior to therapeutic intervention and to normal age and sex matched donors. Twenty-three pts have been followed a median of 29 months (range 5.5–50.5 months) from study entry. Two patients relapsed 8 and 23 months after diagnosis. T-cell CD-4 numbers declined following AC from an average of 4.9±0.5 ×106/ml to 1.7±0.3×106/ml, but increased to an average of 2.7± 0.3 × 106/ml, 21 weeks after P or 12 weeks after R. In this study the MDSCs were defined as Lin- (CD3, CD19, CD14 and CD13), HLA-DR- and CD33+. The numbers of MDSCs, which in normal donors were 0.62±0.16×106/ml and in the cancer patients at diagnosis were 11.8±9.6×106/ml increased to 58.4±25.9×106/ml 15 weeks after R. They remained significantly elevated through one year after diagnosis when they were 27.3±12.3×106/ml. The majority of the MDSCs had a high side scatter and forward scatter by flow analysis suggesting a granulocytic commitment rather than a monocytic commitment. The increase in MDSC numbers was apparently associated with R as the numbers of MDSCs were not significantly increased by AC (15.7±13.5×106/ml) or P (10.9±6×106/ml) one week following completion of each cycle of dose dense therapy. In association with the increase in MDSCs there was a significant decrease in PHA proliferation by the peripherial blood mononuclear cells (MNCs) and suppressive activity by irradiated MNC for allergenic lymphocytes.


2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 126-126
Author(s):  
Jaspreet Singh Grewal ◽  
Numan Al-Rayyan ◽  
Jamaal Ritchie ◽  
Paxton Schowe ◽  
Cam Falkner ◽  
...  

126 Background: Myeloid derived suppressor cells (MDSCs) inhibit the expansion of tumor antigen-specific effector CD8+ T cells via different mechanisms including increased expression of arginase, transforming growth factor – β (TGF – β) and indoleamine 2,3-dioxygenase (IDO). Recently, MDSCs were found to over-express hypoxia inducible factor 1 alpha (HIF-1α) which is required for their differentiation. An essential transcriptional target of HIF-1α is 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) which synthesizes fructose 2,6-bisphosphate, an allosteric stimulator of glycolysis and of proliferation via stimulation of cyclin dependent kinase-1 (CDK1). We hypothesized that MDSCs might over-express PFKFB3 which in turn might be required for their function as T cell suppressors. Methods: We used monocytic MDSCs (M-MDSCs) induced by co-culture with A375 melanoma cells, M-MDSCs from metastatic melanoma patients, murine bone marrow MDSCs and splenic M-MDSCs from B16 F10 tumor bearing mice for our studies. T cell suppression assays were performed to analyze M-MDSC suppression and reversal following PFKFB3 blockade. Results: We found that M-MDSCs have increased PFKFB3 expression. We also found that PFK-158 administration in B16 (wild-type) melanoma-bearing mice results in a marked reduction in MDSCs and a simultaneous increase in CD8+ T cell infiltration in the tumors. We analyzed three advanced cancer patients for circulating MDSCs before and after PFK-158 administration as part of a multi-center phase 1 clinical trial. And, we found that the MDSCs were markedly reduced in each patient. In addition, we have generated data for MDSC suppressive activity following in vitro treatment with PFK-158 showing reversal of suppressive activity. Conclusions: Taken together, these data indicate that selective inhibition of PFKFB3 may be a novel approach to target MDSCs and combinations of PFKFB3 inhibitors with immunotherapies may be a rational strategy to promote durable immune-mediated remissions in cancer patients.


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e15203-e15203
Author(s):  
Di Zhang ◽  
Lihua Shi ◽  
Susan Tam ◽  
Man-Cheong Fung

e15203 Background: Although checkpoint inhibitor immunotherapy and adoptive T-cell therapy revolutionized cancer treatments, such approaches suffer either from lack of target specificity for checkpoint inhibitors or inability to target intracellular tumor-related antigens from CAR-T therapy. Here, we report the development of novel Tavo Immune Modulator (TIM) biologics molecules which can specifically recognize tumor antigen-specific T cells through an engineered pMHC complex with peptides derived from intracellular tumor-related antigens. These molecules can selectively activate such T cells through engineered T cell co-stimulatory modulators for enhanced tumor cell killing. Methods: NY-ESO-1 and MAGE-A10 TIM molecules were constructed as fusions of HLA-A*02:01 MHC complexed with either NY-ESO-1 (157-165) or MAGE-A10 (254-262) epitope peptides at the N-termini and various T cell costimulatory modulators at the C-termini of IgG heavy and light chains. TIM molecules were expressed in Expi293 cells and purified by Protein A affinity chromatography. Specific binding of TIM with cancer specific T cells was evaluated by immunostaining. The activation and proliferation of tumor specific CD8+ T cells were confirmed in T cell activation and recall assays. Results: Both NY-ESO-1 and MAGE-A10 specific TIM molecules were generated which recognized corresponding tumor specific T cells. NY-ESO-1 TIM engineered with IL2 could activate NY-ESO-1 specific CD8+ T cell exclusively. Engineering additional T cell costimulatory factors along with IL2 on NY-ESO-1 TIM molecule could further boost T cell proliferation and activation in T cell recall assays. Besides NY-ESO-1, combinations of T cell costimulatory factors with MAGE-A10 TIM molecules enhanced specific T cell activation. Additional in vitro and in vivo studies are ongoing to demonstrate efficacy of such novel TIM molecules in eliminating different types of NY-ESO-1 and MAGE-A10 which are over-expressed on tumor cells. Conclusions: This study demonstrates the utility of NY-ESO-1 and MAGE-A10 TIM molecules in the selective recognition and activation of tumor antigen-specific T cells. Such novel biologics molecules may provide target specificity in tumor treatment, and potential targeting of intracellular tumor-related antigens presented as peptides in MHC complexes on cell surfaces. Selective activation of tumor-specific T cells may provide a unique method for the treatment of various solid tumors and warrants further investigation.


Cancers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 5127
Author(s):  
Yijun Wang ◽  
Tongyue Zhang ◽  
Mengyu Sun ◽  
Xiaoyu Ji ◽  
Meng Xie ◽  
...  

One of the major challenges in hepatocellular carcinoma (HCC) treatment is drug resistance and low responsiveness to systemic therapies, partly due to insufficient T cell infiltration. Myeloid-derived suppressor cells (MDSCs) are immature marrow-derived cell populations with heterogeneity and immunosuppression characteristics and are essential components of the suppressive tumor immune microenvironment (TIME). Increasing evidence has demonstrated that MDSCs are indispensable contributing factors to HCC development in a T cell-dependent or non-dependent manner. Clinically, the frequency of MDSCs is firmly linked to HCC clinical outcomes and the effectiveness of immune checkpoint inhibitors (ICIs) and tyrosine kinase inhibitors (TKIs). Furthermore, MDSCs can also be used as prognostic and predictive biomarkers for patients with HCC. Therefore, treatments reprograming MDSCs may offer potential therapeutic opportunities in HCC. Here, we recapitulated the dynamic relevance of MDSCs in the initiation and development of HCC and paid special attention to the effect of MDSCs on T cells infiltration in HCC. Finally, we pointed out the potential therapeutic effect of targeting MDSCs alone or in combination, hoping to provide new insights into HCC treatment.


2020 ◽  
Vol 8 (2) ◽  
pp. e000668
Author(s):  
Troels Holz Borch ◽  
Rikke Andersen ◽  
Eva Ellebaek ◽  
Özcan Met ◽  
Marco Donia ◽  
...  

Personalized cell therapy targeting tumor antigens with expanded tumor-infiltrating lymphocytes (TILs) has shown great promise in metastatic melanoma (MM) since the 90s. However, MM was first-in line to benefit from the wave of checkpoint inhibitors (CPI), which shifted the focus of immunotherapy almost fully to immune CPI. Still, the majority of patients fail to benefit from CPI treatment, raising the intriguing question on how TIL therapy may fit into the changing landscape of melanoma treatment. We took advantage of data from a unique cohort of patients with MM treated with T-cell therapy in consecutive clinical trials at our institution across the last 10 years. Based on detailed data on patient characteristics, pre-TIL and post-TIL treatments and long-term follow-up, we were able to address the important issue of how TIL therapy can be positioned in the current CPI era. We found that previous progression on anticytotoxic T-lymphocyte-associated protein 4 do not seem to harm neither rate nor duration of response to TIL therapy. Importantly, even in the hard-to-treat population of patients who progressed on antiprogrammed cell death protein 1 (anti-PD-1), an objective response rate of 32% was achieved, including durable responses. Yet, median progression-free survival was reduced in this anti-PD-1 refractory population. Trial registration number: ClinicalTrials.gov ID: NCT00937625, NCT02379195 and NCT02354690.


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