scholarly journals Loss of TCF-1 regulates production of noncanonical Tregs in a prion-like manner

2021 ◽  
Author(s):  
Rebecca Harris ◽  
Mahinbanu Mammadli ◽  
Mobin Karimi
Keyword(s):  
T Cells ◽  
Transcriptional Regulation ◽  
Regulatory T Cells ◽  
Immune Cells ◽  
Chimeric Mouse ◽  
Aberrant Expression ◽  
Therapeutic Applications ◽  
Donor Cells ◽  
A Cell

AbstractRegulatory T cells (Tregs) are suppressive immune cells used for a variety of clinical and therapeutic applications. Canonical Tregs express CD4, FOXP3, and CD25, which are considered definitive markers of Treg status when used together. However, a subset of noncanonical Tregs expressing only CD4 and FOXP3 have recently been described in some infection contexts. The transcriptional regulation of these cells is still unclear. We found that loss of TCF-1 in all T cells in mice leads to expansion of these cells in multiple tissues in a cell-intrinsic fashion. This effect was not due to aberrant expression of FOXP3, as other functional Treg markers were also expressed. In addition, presence of TCF-1-deficient cells in a chimeric mouse induced increased production of noncanonical Tregs from WT donor cells. Therefore, targeting of TCF-1 may remove suppression on this Treg lineage, increasing the yield of these cells for use in the clinic.Summary sentenceLoss of TCF-1 causes expansion of CD25- FOXP3+ noncanonical Tregs, and TCF-1-deficient T cells induce increased production of CD25- Tregs from WT cells.

scholarly journals METTL3-dependent m6A modification programs T follicular helper cell differentiation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yingpeng Yao ◽  
Ying Yang ◽  
Wenhui Guo ◽  
Lifan Xu ◽  
Menghao You ◽  
...  
Keyword(s):  
T Cells ◽  
Transcriptional Regulation ◽  
Cell Differentiation ◽  
Ectopic Expression ◽  
Signature Genes ◽  
Follicular Helper ◽  
Conditional Deletion ◽  
A Cell ◽  
A Site ◽  
Post Transcriptional Regulation

AbstractT follicular helper (TFH) cells are specialized effector CD4+ T cells critical to humoral immunity. Whether post-transcriptional regulation has a function in TFH cells is unknown. Here, we show conditional deletion of METTL3 (a methyltransferase catalyzing mRNA N6-methyladenosine (m6A) modification) in CD4+ T cells impairs TFH differentiation and germinal center responses in a cell-intrinsic manner in mice. METTL3 is necessary for expression of important TFH signature genes, including Tcf7, Bcl6, Icos and Cxcr5 and these effects depend on intact methyltransferase activity. m6A-miCLIP-seq shows the 3′ UTR of Tcf7 mRNA is subjected to METTL3-dependent m6A modification. Loss of METTL3 or mutation of the Tcf7 3′ UTR m6A site results in accelerated decay of Tcf7 transcripts. Importantly, ectopic expression of TCF-1 (encoded by Tcf7) rectifies TFH defects owing to METTL3 deficiency. Our findings indicate that METTL3 stabilizes Tcf7 transcripts via m6A modification to ensure activation of a TFH transcriptional program, indicating a pivotal function of post-transcriptional regulation in promoting TFH cell differentiation.

scholarly journals The role of FoxP3+ regulatory T cells and IDO+ immune and tumor cells in malignant melanoma – an immunohistochemical study

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Satu Salmi ◽  
Anton Lin ◽  
Benjamin Hirschovits-Gerz ◽  
Mari Valkonen ◽  
Niina Aaltonen ◽  
...  
Keyword(s):  
T Cells ◽  
Prognostic Factors ◽  
Regulatory T Cells ◽  
Tumor Cells ◽  
Immune Cells ◽  
Positive Association ◽  
Tumor Stage ◽  
Melanoma Cells ◽  
Melanoma Progression

Abstract Background FoxP3+ Regulatory T cells (Tregs) and indoleamine-2,3-dioxygenase (IDO) participate in the formation of an immunosuppressive tumor microenvironment (TME) in malignant cutaneous melanoma (CM). Recent studies have reported that IDO expression correlates with poor prognosis and greater Breslow’s depth, but results concerning the role of FoxP3+ Tregs in CM have been controversial. Furthermore, the correlation between IDO and Tregs has not been substantially studied in CM, although IDO is known to be an important regulator of Tregs activity. Methods We investigated the associations of FoxP3+ Tregs, IDO+ tumor cells and IDO+ stromal immune cells with tumor stage, prognostic factors and survival in CM. FoxP3 and IDO were immunohistochemically stained from 29 benign and 29 dysplastic nevi, 18 in situ -melanomas, 48 superficial and 62 deep melanomas and 67 lymph node metastases (LNMs) of CM. The number of FoxP3+ Tregs and IDO+ stromal immune cells, and the coverage and intensity of IDO+ tumor cells were analysed. Results The number of FoxP3+ Tregs and IDO+ stromal immune cells were significantly higher in malignant melanomas compared with benign lesions. The increased expression of IDO in melanoma cells was associated with poor prognostic factors, such as recurrence, nodular growth pattern and increased mitotic count. Furthermore, the expression of IDO in melanoma cells was associated with reduced recurrence˗free survival. We further showed that there was a positive correlation between IDO+ tumor cells and FoxP3+ Tregs. Conclusions These results indicate that IDO is strongly involved in melanoma progression. FoxP3+ Tregs also seems to contribute to the immunosuppressive TME in CM, but their significance in melanoma progression remains unclear. The positive association of FoxP3+ Tregs with IDO+ melanoma cells, but not with IDO+ stromal immune cells, indicates a complex interaction between IDO and Tregs in CM, which demands further studies.

scholarly journals 873 Pharmacologic macrophage depletion affects metastasis formation by modulating systemic immune responses in a genetic pancreatic cancer model

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A926-A926
Author(s):  
Heidi Griesmann ◽  
Heidi Griesmann ◽  
Heidi Griesmann ◽  
Christof Drexel ◽  
Nada Milosevic ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
T Cells ◽  
Regulatory T Cells ◽  
Mouse Model ◽  
Immune Cells ◽  
Tumour Progression ◽  
Metastasis Formation ◽  
Macrophage Depletion ◽  
Genetic Mouse Model ◽  
Liposomal Clodronate

BackgroundTumour-associated macrophages (TAM) play an important role in mediating tumour progression. In pancreatic cancer, infiltrating macrophages have been identified not only in invasive tumours, but also in early preinvasive pancreatic intraepithelial neoplasias and are known to mediate tumour progression.MethodsWe aimed to study the impact of pharmacological macrophage depletion by liposomal clodronate in the genetic mouse model of pancreatic cancer (KPC mouse: LSL-KrasG12D/+;LSL-Trp53R172H/+;Pdx-1-Cre). KPC mice were treated with liposomal clodronate or control liposomes from week 8 to week 20. Tumour and metastasis formation as well as alterations in local and circulating immune cells and cytokines were analysed.ResultsTreatment with liposomal clodronate effectively reduced CD11b-positive macrophages both in the pancreas and other organs such as liver, lung and spleen. Tumour incidence and size was only slightly reduced. However, metastasis formation in the liver und lungs was markedly diminished after macrophage depletion. Reduced macrophage count was associated with significant alterations in circulating growth factors and mediators known to be secreted by macrophages and associated with angiogenesis, most prominently VEGF. Moreover, application of liposomal clodronate led to marked alterations in circulating immune cells, among them reduced regulatory T cells.ConclusionsPharmacological depletion of macrophages in a genetic mouse model of pancreatic cancer markedly reduced metastasis formation and is associated with modulated profile of both secreted mediators and regulatory T cells. Pharmacological modulation of infiltrating macrophages represents a promising avenue for antimetastatic therapeutic approaches.

scholarly journals The Complex Role of Regulatory T Cells in Immunity and Aging

2021 ◽  
Vol 11 ◽  
Author(s):  
Lourdes Rocamora-Reverte ◽  
Franz Leonard Melzer ◽  
Reinhard Würzner ◽  
Birgit Weinberger
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Immune Responses ◽  
Immune Cells ◽  
Treg Cells ◽  
T Cell Subsets ◽  
Γδt Cells ◽  
Cell Functions ◽  
Age Related ◽  
Self Antigens

The immune system is a tightly regulated network which allows the development of defense mechanisms against foreign antigens and tolerance toward self-antigens. Regulatory T cells (Treg) contribute to immune homeostasis by maintaining unresponsiveness to self-antigens and suppressing exaggerated immune responses. Dysregulation of any of these processes can lead to serious consequences. Classically, Treg cell functions have been described in CD4+ T cells, but other immune cells also harbour the capacity to modulate immune responses. Regulatory functions have been described for different CD8+ T cell subsets, as well as other T cells such as γδT cells or NKT cells. In this review we describe the diverse populations of Treg cells and their role in different scenarios. Special attention is paid to the aging process, which is characterized by an altered composition of immune cells. Treg cells can contribute to the development of various age-related diseases but they are poorly characterized in aged individuals. The huge diversity of cells that display immune modulatory functions and the lack of universal markers to identify Treg make the expanding field of Treg research complex and challenging. There are still many open questions that need to be answered to solve the enigma of regulatory T cells.

scholarly journals Transcriptional heterogeneity in cancer-associated regulatory T cells is predictive of survival

2018 ◽  
Author(s):  
Nicholas Borcherding ◽  
Kawther K. Ahmed ◽  
Andrew P. Voigt ◽  
Ajaykumar Vishwakarma ◽  
Ryan Kolb ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Immune Cells ◽  
Ex Vivo ◽  
Expression Patterns ◽  
Suppressive Effect ◽  
Renal Clear Cell Carcinoma ◽  
Cell Fates ◽  
Treg Subset

Regulatory T cells (Tregs) are a population of T cells that exert a suppressive effect on a variety of immune cells and non-immune cells. The suppressive effects of Tregs are detrimental to anti-tumor immunity. Recent investigations into cancer-associated Tregs have identified common expression patterns for tumor-infiltration, however the functional heterogeneity in tumor-infiltrating (TI) Treg is largely unknown. We performed single-cell sequencing on immune cells derived from renal clear cell carcinoma (ccRCC) patients, isolating 160 peripheral-blood (PB) Tregs and 574 TI Tregs. We identified distinct transcriptional TI Treg cell fates, with a suppressive subset expressing CD177. We demonstrate CD177+ TI-Tregs have preferential suppressive effects in vivo and ex vivo. Gene signatures derived the CD177+ Treg subset had superior ability to predict survival in ccRCC and seven other cancer types. Further investigation into the development and regulation of TI-Treg heterogeneity will be vital to the application of tumor immunotherapies that possess minimal side effects.

scholarly journals Targeting regulatory T cells for immunotherapy in melanoma

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Lili Huang ◽  
Yeye Guo ◽  
Shujing Liu ◽  
Huaishan Wang ◽  
Jinjin Zhu ◽  
...  
Keyword(s):  
T Cells ◽  
Tumor Microenvironment ◽  
Regulatory T Cells ◽  
Immune Responses ◽  
Immune Cells ◽  
Therapeutic Efficacy ◽  
Patient Survival ◽  
Therapeutic Antibodies ◽  
Promising Strategy ◽  
Fine Tune

AbstractRegulatory T cells (Tregs) are essential in the maintenance of immunity, and they are also a key to immune suppressive microenvironment in solid tumors. Many studies have revealed the biology of Tregs in various human pathologies. Here we review recent understandings of the immunophenotypes and suppressive functions of Tregs in melanoma, including Treg recruitment and expansion in a tumor. Tregs are frequently accumulated in melanoma and the ratio of CD8+ T cells versus Tregs in the melanoma is predictive for patient survival. Hence, depletion of Tregs is a promising strategy for the enhancement of anti-melanoma immunity. Many recent studies are aimed to target Tregs in melanoma. Distinguishing Tregs from other immune cells and understanding the function of different subsets of Tregs may contribute to better therapeutic efficacy. Depletion of functional Tregs from the tumor microenvironment has been tested to induce clinically relevant immune responses against melanomas. However, the lack of Treg specific therapeutic antibodies or Treg specific depleting strategies is a big hurdle that is yet to be overcome. Additional studies to fine-tune currently available therapies and more agents that specifically and selectively target tumor infiltrating Tregs in melanoma are urgently needed.

Challenges in cryopreservation of regulatory T cells (Tregs) for clinical therapeutic applications

2013 ◽  
Vol 16 (3) ◽  
pp. 371-375 ◽  
Author(s):  
Karolina Golab ◽  
Dennis Leveson-Gower ◽  
Xiao-Jun Wang ◽  
Jakub Grzanka ◽  
Natalia Marek-Trzonkowska ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Therapeutic Applications
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