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Reverse transcription quantitative polymerase chain reaction primers.
Source publication
Background aims:
Mesenchymal stromal cells (MSCs) are a multipotent cell population of clinical interest because of their ability to migrate to injury and tumor sites, where they may participate in tissue repair and modulation of immune response. Although the processes regulating MSC function are incompletely understood, it has been shown that sti...
Context in source publication
Context 1
... transcription was performed for 0.5 mg of each RNA sample using amfiRivert Platinum cDNA Synthesis Master Mix (GenDE-POT, Katy, TX, USA). Reverse transcription quantitative polymerase chain reaction contained 1 mL complementary DNA template, 2£ SYBR Green Master Mix (Thermo Fisher Scientific) and 1 mM forward and reverse primers for target genes or beta-actin (Integrated DNA Technologies, Coralville, IA, USA) as a housekeeping control (Table 1). Reverse transcription quantitative polymerase chain reaction was performed in a ViiA 7 Real-Time PCR System (Thermo Fisher Scientific) using the following conditions: 95°C for 3 min and 40 cycles of ...Citations
... Damage-associated molecular patterns (DAMPs) or pathogen-associated molecular patterns (PAMPs) present in this micro-environment induce plastic changes in MSCs' immunoregulatory functions by activating distinct TLRs [22,23]. Among these, TLR4 activation leads to polarization of MSCs towards a pro-inflammatory phenotype characterized by IL-6 secretion, while TLR3 activation results in polarization towards an anti-inflammatory phenotype dominated by IL-10 secretion [24]. Additionally, Duan. ...
Background
The therapeutic efficacy of intra-articular mesenchymal stem cells (MSCs) injection for patients with osteoarthritis (OA) currently exhibits inconsistency, and the underlying mechanism remains elusive. It has been postulated that the immunomodulatory properties and paracrine activity of MSCs might be influenced by the inflammatory micro-environment within osteoarthritic joints, potentially contributing to this observed inconsistency.
Methods
Adipose-derived MSCs (ADSCs) were isolated from SD rats and pre-treated with Toll-like receptor 3 (TLR3) agonist Poly I:C or Toll-like receptor 4 (TLR4) agonist LPS. The pre-treated ADSCs were then co-cultured with IL-1β-induced osteoarthritic chondrocytes using a Transwell system to analyze the paracrine effect of ADSCs on reversing the osteoarthritic phenotype of chondrocytes.
Results
RT-PCR and Western blot analysis revealed that Poly I:C and LPS pre-treatments up-regulated the expression of IL-10 and IL-6 in ADSCs, respectively. Furthermore, only Poly I:C-preconditioned ADSCs significantly promoted proliferation while inhibiting apoptosis in IL-1β-treated chondrocytes. Additionally, Poly I:C-preconditioned ADSCs downregulated MMP13 expression while upregulating aggrecan and collagen II expression levels in IL-1β-treated chondrocytes.
Conclusions
TLR3 activation polarizes ADSCs into an immunomodulatory phenotype distinct from TLR4 activation, exerting differential effects on reversing the osteoarthritic phenotype of chondrocytes; thus indicating that MSCs’ paracrine effect regulated by TLRs signaling impacts the efficacy of intra-articular MSCs injection.
... TLR3/4 priming of MSCs may reprogram them toward an anti-tumour phenotype and modulate the immune-mediated killing of tumour cells by up-regulating pro-inflammatory factors. It is linked to the activation of immune cells by MSCs in vitro and the retardation of tumour cells [34]. ...
Background and aims
Glioblastoma (GBM) is an aggressive primary brain cancer with no promising curative therapies. It has been indicated that MSCs can interact with the tumour microenvironment (TME) through the secretion of soluble mediators regulating intercellular signalling within the TME. TLRs are a multigene family of pattern recognition receptors with evolutionarily conserved regions and are widely expressed in immune and other body cells. MSCs by TLRs can recognize conserved molecular components (DAPMPs and PAPMPs) and activate signalling pathways, which regulate immune and inflammatory responses. MSCs may exert immunomodulatory functions through interaction with their expressed toll-like receptors (TLRs) and exert a protective effect against tumour antigens. As an emerging approach, we aimed to monitor the U87 cell line growth, migration and death markers following specific TLR3/4-primed-MSCs-CMs treatment.
Methods and results
We investigated the phenotypic and functional outcomes of primed-CMs and glioma cell line co-culture following short-term, low-dose TLR3/4 priming. The gene expression profile of target genes, including apoptotic markers and related genes, was analyzed by qRT-PCR. MicroRNA-Seq examined the miRNA expression patterns, and flow cytometry evaluated the cell viability and cycle stages. The results showed significant changes in apoptosis and likely necroptosis-related markers following TLR3/4-primed-MSCs-CMs exposure in the glioma cell line. Notably, we observed a considerable induction of selective pro-apoptotic markers and both the early and late stages of apoptosis in treated U87 cell lines. Additionally, the migration rate of glioma cells significantly decreased following MSCs-CM treatment.
Conclusion
Our findings confirmed that the exposure of TLR3/4-activated-MSCs-CMs with glioma tumour cells possibly changes the immunogenicity of the tumour microenvironment and induces immunogenic programmed cell death. Our results can support the idea that TLR3/4-primed-MSCs can lead to innate immune-mediated cell death and modify tumour cell biology in invasive and metastatic cancers.
... While BM-MSC remain the most commonly studied MSC subtype, and were the focus of the MSC polarization paradigm reports, MSC derived from other tissues may provide advantages for clinical use such as higher relative abundance and differential functional potential (Strioga et al., 2012). In our previous work (Rivera-Cruz and Figueiredo, 2023), we had identified phenotypical and functional consequences of TLR priming on ASC that partially resembled those previously reported for BM-MSC (Waterman et al., 2010). In our assessment, LPS-priming of ASC rendered them immunostimulatory in immune killing assay coculture assays in the presence of human prostate adenocarcinoma cells and stimulated peripheral blood mononuclear cells. ...
... These findings are interesting in that they partially recapitulate the effects of MSC-tumor interactions observed in the initial polarization reports, in that poly I:C induced a pro-tumorigenic action by the BM-MSC treatments (Waterman et al., 2012). Yet, the potentially anti-tumorigenic effects of LPS-primed cells reported by this group and suggested in our ASC in vitro experiments (Rivera-Cruz and Figueiredo, 2023) were not evident in these in vivo experiments. There are many potential reasons for these observed differences. ...
Introduction: Mesenchymal stromal cells (MSC) are envisioned as a potential cellular vehicle for targeted cancer therapies due to their tumor tropism and immune permissiveness. An obstacle in their use is the duality in their interactions within tumors, rendering them pro-tumorigenic or anti-tumorigenic, in a context dependent manner. MSC preconditioning, or priming, has been proposed as a strategy for directing the effector properties of MSC at tumor sites.
Methods: We primed human MSC derived from adipose tissues (ASC), a clinically advantageous MSC source, utilizing toll-like receptor agonists. Subsequently, we explored the consequences in tumor progression and transcriptome upon the interaction of tumor cells with primed or unprimed ASC in an in vivo model of prostate cancer, the second most common cancer and second leading cause of cancer related death in men in the USA.
Results and discussion: In the studied model, poly I:C-primed ASC were found to significantly accelerate tumor growth progression. And while unprimed and LPS-primed ASC did not exert a significant effect on tumor growth at the macroscopic level, gene expression analyses suggested that all treatments promoted distinct modulatory effects in the tumor microenvironment, including altered modulation of angiogenesis, and immune response processes. However, the effects resulting from the collective interaction across these processes must be sufficiently skewed in a pro-tumorigenic or anti-tumorigenic direction for evidence of tumor progression modulation to be detectable at the macroscopic level. Our study highlights potential MSC-tumor microenvironment interactions that may be leveraged and should be considered in the development of cancer therapeutics utilizing MSC.
... Thus, LPS-stimulated MSC1 expressed higher levels of IL-6 and IL-8 mRNAs than poly(I:C)-stimulated MSC2, which inversely expressed immunomodulatory factors, such as IDO, PGE2, and IL-10, at much higher levels than LPS-stimulated MSC1 [103]. Similar observations have been made for ASCs, which, depending on TLR3 or TLR4 stimuli, could behave as immunomodulatory or inflammatory cells, respectively [104]. ...
Adipose tissue-derived mesenchymal stem cells (ASCs) are adult stem cells, endowed with self-renewal, multipotent capacities, and immunomodulatory properties, as mesenchymal stem cells (MSCs) from other origins. However, in a pathological context, ASCs like MSCs can exhibit pro-inflammatory properties and attract inflammatory immune cells at their neighborhood. Subsequently, this creates an inflammatory microenvironment leading to ASCs’ or MSCs’ dysfunctions. One such example is given by obesity where adipogenesis is impaired and insulin resistance is initiated. These opposite properties have led to the classification of MSCs into two categories defined as pro-inflammatory ASC1 or anti-inflammatory ASC2, in which plasticity depends on the micro-environmental stimuli. The aim of this review is to (i) highlight the pathogenic role of ASCs during obesity and obesity-related inflammatory diseases, such as rheumatoid arthritis, multiple sclerosis, psoriasis, inflammatory bowel disease, and cancer; and (ii) describe some of the mechanisms leading to ASCs dysfunctions. Thus, the role of soluble factors, adhesion molecules; TLRs, Th17, and Th22 cells; γδ T cells; and immune checkpoint overexpression will be addressed.
Human adipose tissue-derived stem/stromal cells (hASCs) are adult multipotent mesenchymal stem/stromal cells with immunomodulatory capacities. Here, we present up-to-date knowledge on the impact of different experimental and donor-related factors on hASC immunoregulatory functions in vitro. The experimental determinants include the immunological status of hASCs relative to target immune cells, contact vs. contactless interaction, and oxygen tension. Factors such as the ratio of hASCs to immune cells, the cellular context, the immune cell activation status, and coculture duration are also discussed. Conditioning of hASCs with different approaches before interaction with immune cells, hASC culture in xenogenic or xenofree culture medium, hASC culture in two-dimension vs. three-dimension with biomaterials, and the hASC passage number are among the experimental parameters that greatly may impact the hASC immunosuppressive potential in vitro, thus, they are also considered. Moreover, the influence of donor-related characteristics such as age, sex, and health status on hASC immunomodulation in vitro is reviewed. By analysis of the literature studies, most of the indicated determinants have been investigated in broad non-standardized ranges, so the results are not univocal. Clear conclusions cannot be drawn for the fine-tuned scenarios of many important factors to set a standard hASC immunopotency assay. Such variability needs to be carefully considered in further standardized research. Importantly, field experts’ opinions may help to make it clearer.
Graphical Abstract
Parameters that promote ASC immunosuppression on immune cells. Activation of immune cells induces their proliferation and differentiation and presence of ASCs modulates/suppresses such consequences. Augmented immunosuppressive effects of ASCs can be introduced in direct contact with the immune cells and via complementing the repeatedly reported experimental settings (texts in grey shapes). Abbreviations: ASCs: adipose tissue-derived stem/stromal cells, IFN-ɤ: Interferon gamma, MLR: Mixed lymphocyte reaction, TNF: Tumor necrosis factor.
