Minimum Information about T Regulatory Cells: A Step toward Reproducibility and Standardization.

Cellular therapies with CD4+ T regulatory cells (Tregs) hold promise of efficacious treatment for the variety of autoimmune and allergic diseases as well as posttransplant complications. Nevertheless, current manufacturing of Tregs as a cellular medicinal product varies between different laboratories, which in turn hampers precise comparisons of the results between the studies performed. While the number of clinical trials testing Tregs is already substantial, it seems to be crucial to provide some standardized characteristics of Treg products in order to minimize the problem. We have previously developed reporting guidelines called minimum information about tolerogenic antigen-presenting cells, which allows the comparison between different preparations of tolerance-inducing antigen-presenting cells. Having this experience, here we describe another minimum information about Tregs (MITREG). It is important to note that MITREG does not dictate how investigators should generate or characterize Tregs, but it does require investigators to report their Treg data in a consistent and transparent manner. We hope this will, therefore, be a useful tool facilitating standardized reporting on the manufacturing of Tregs, either for research purposes or for clinical application. This way MITREG might also be an important step toward more standardized and reproducible testing of the Tregs preparations in clinical applications

TrkAIII Promotes Microtubule Nucleation and Assembly at the Centrosome in SH-SY5Y Neuroblastoma Cells, Contributing to an Undifferentiated Anaplastic Phenotype

The alternative TrkAIII splice variant is expressed by advanced stage human neuroblastomas (NBs) and exhibits oncogenic activity in NB models. In the present study, employing stable transfected cell lines and assays of indirect immunofluorescence, immunoprecipitation, Western blotting, microtubule regrowth, tubulin kinase, and tubulin polymerisation, we report that TrkAIII binds α-tubulin and promotes MT nucleation and assembly at the centrosome. This effect depends upon spontaneous TrkAIII activity, TrkAIII localisation to the centrosome and pericentrosomal area, and the capacity of TrkAIII to bind, phosphorylate, and polymerise tubulin. We propose that this novel role for TrkAIII contributes to MT involvement in the promotion and maintenance of an undifferentiated anaplastic NB cell morphology by restricting and augmenting MT nucleation and assembly at the centrosomal MTOC

The TrkAIII oncoprotein inhibits mitochondrial free radical ROS-induced death of SH-SY5Y neuroblastoma cells by augmenting SOD2 expression and activity at the mitochondria, within the context of a tumour stem cell-like phenotype.

The developmental and stress-regulated alternative TrkAIII splice variant of the NGF receptor TrkA is expressed by advanced stage human neuroblastomas (NBs), correlates with worse outcome in high TrkA expressing unfavourable tumours and exhibits oncogenic activity in NB models. In the present study, we report that constitutive TrkAIII expression in human SH-SY5Y NB cells inhibits Rotenone, Paraquat and LY83583-induced mitochondrial free radical reactive oxygen species (ROS)-mediated death by stimulating SOD2 expression, increasing mitochondrial SOD2 activity and attenuating mitochondrial free radical ROS production, in association with increased mitochondrial capacity to produce H2O2, within the context of a more tumour stem cell-like phenotype. This effect can be reversed by the specific TrkA tyrosine kinase inhibitor GW441756, by the multi-kinase TrkA inhibitors K252a, CEP-701 and Gö6976, which inhibit SOD2 expression, and by siRNA knockdown of SOD2 expression, which restores the sensitivity of TrkAIII expressing SH-SY5Y cells to Rotenone, Paraquat and LY83583-induced mitochondrial free radical ROS production and ROS-mediated death. The data implicate the novel TrkAIII/SOD2 axis in promoting NB resistance to mitochondrial free radical-mediated death and staminality, and suggest that the combined use of TrkAIII and/or SOD2 inhibitors together with agents that induce mitochondrial free radical ROS-mediated death could provide a therapeutic advantage that may also target the stem cell niche in high TrkA expressing unfavourable NB

ABCC3 Expressed by CD56dim CD16+ NK Cells Predicts Response in Glioblastoma Patients Treated with Combined Chemotherapy and Dendritic Cell Immunotherapy

Recently, we found that temozolomide (TMZ) can upregulate the expression of the multidrug-resistance protein ABCC3 in NK cells from both glioma-bearing mice and glioblastoma patients treated with dendritic cell immunotherapy combined with TMZ, allowing NK cells to escape apoptosis and favoring their role as antitumor effector cells. Here, we demonstrate that CD56dim NK cells expressing CD16+ are predominant in patients surviving more than 12 months after surgery without disease progression. CD56dim CD16+ NK cells co-expressed high levels of ABCC3 and IFN-γ. Notably, not only basal but also TMZ-induced ABCC3 expression was related to a strong, long-term NK cell response and a better prognosis of patients. The identification of the single nucleotide polymorphism (SNP) rs35467079 with the deletion of a cytosine (−897DelC) in the promoter region of the ABCC3 gene resulted associated with a better patient outcome. ABCC3 expression in patients carrying DelC compared to patients with reference haplotype was higher and modulated by TMZ. The transcription factor NRF2, involved in ABCC3 induction, was phosphorylated in CD56dim CD16+ NK cells expressing ABCC3 under TMZ treatment. Thus, ABCC3 protein and the SNP −897DelC can play a predictive role in patients affected by GBM, and possibly other cancers, treated with dendritic cell immunotherapy combined with chemotherapy

Alendronate promotes plasmin-mediated MMP-9 inactivation by exposing cryptic plasmin degradation sites within the MMP-9 catalytic domain

Irreversible MMP-9 inhibition is considered a significant therapeutic goal in inflammatory, vascular and tumour pathology. We report that divalent cation chelators Alendronate and EDTA not only directly inhibited MMP-9 but also promoted irreversible plasmin-mediated MMP-9 inactivation by exposing cryptic plasmin-degradation sites within the MMP-9 catalytic-domain and producing an inhibitory hemopexin-domain fragment. This effect was also observed using MDA-MB-231 breast cancer cells, which activated exogenous plasminogen to degrade endogenous proMMP-9 in the presence of Alendronate or EDTA. Degradation-mediated inactivation of proMMP-9 occurred in the absence of transient activation, attesting to the incapacity of plasmin to directly activate proMMP-9 and direct MMP-9 inhibition by Alendronate and EDTA. Our study provides a novel rational for therapeutic Alendronate use in MMP-9-dependent pathology characterised by plasminogen activation. Crown Copyright © 2012 Published by Elsevier B.V. on behalf of Federation of European Biochemical society. All rights reserved

SOD2 expression in TrkAIII SH-SY5Y cells is reduced by TrkA, IP3K and NF-κB inhibitors.

<p>A) Western blots demonstrating relative differences in TrkA, TrkAIII, phosphorylated TrkA (pY674/675-TrkA), SOD2, Trx-2 and α-tubulin levels in equal protein concentrations (20 µg) of total extracts from TrkA and TrkAIII SH-SY5Y cell lines, treated without (Con) or with 1 µM CEP-701 (CEP), 1 µM K252a (K2); 25 µM LY294002 (LY294) or 1 µM Gö6976 (Gö69) for 24 hours, at 37°C. B) Representative Western blots demonstrating relative differences in SOD2 and α-tubulin levels in equal protein concentrations (20 µg) of total extracts from TrkA and TrkAIII SH-SY5Y cell lines treated without (Con) or with: 100 nM GW441756 (GW44), 500 µM PDTC (PDTC), 100 µM Bay 11–7082 (BAY11) or 30 µM PD098059 (PD098). C) Representative Western blot of total cell extracts (20 µg), demonstrating inhibition of constitutive TrkAIII Y674/675 phosphorylation (Con) following 3 hours treatment of TrkAIII transfectants with 100 nM GW441756 (GW44). D) Histograms showing the densitometric differences in the SOD2 and Trx-2 levels, as a ratio to α-tubulin, in equal concentrations (20 µg) of total cell extracts from TrkA and TrkAIII SH-SY5Y cells treated without (Con) or with: 1 µM CEP-701 (CEP); 1 µM K252a (K2); 25 µM LY294002 (LY294); 1 µM Gö6976 (Gö69); 100 nM GW441756 (GW44); 500 µM PDTC (PDTC); 100 µM Bay 11–7082 (BAY11) or 30 µM PD098059 (PD098), for 24 hours at 37°C. Results are displayed as mean±s.d fold change compared to untreated controls, adjusted to the arbitrary value of 1±s.d., in 3 independent experiments. Mean values are presented above each column and asterisks denote statistical significance by t-test comparison of treated and untreated TrkAIII SH-SY5Y cells. E) Representative Western blots demonstrating differences in TrkAIII, phosphorylated TrkAIII (pTrkAIII), SOD2 and α-tubulin levels in equal concentrations (20 µg) of total cell extracts from wt-TrkAIII and kd-TrkAIII SH-SY5Y cell lines plus a histogram depicting the densitometric difference in the SOD2 levels as a ratio to α-tubulin, in total cell extracts from wt-TrkAIII and kd-TrkAIII SH-SY5Y cells, displayed as mean±s.d fold difference in densitometric ratio with respect to wt-TrkAIII transfectants adjusted to the arbitrary value of 1±s.d., in three independent experiments. Mean values are presented above each column and asterisks denote statistical significance by t-test comparison of wt and kd TrkAIII transfectants. F) Representative Western blots demonstrating levels of TrkA, tyrosine phosphorylated TrkA (pTrkA), SOD2 and α-tubulin in equal concentrations (20 µg) of total cell extracts from untreated TrkA SH-SY5Y cells (Con) and TrkA SH-SY5Y cells treated for 30, 60 and 180 minutes with 100 ng/ml NGF, plus a histogram showing densitometric differences in the SOD2: α-tubulin ratio in total cell extracts from untreated (Con) and NGF-treated TrkA SH-SY5Y cells (100 ng/ml for 30, 60 and 180 minutes), displayed as mean±s.d. fold difference in SOD2 levels with respect to untreated controls adjusted to the arbitrary value of 1±s.d., in 3 independent experiments. Mean values are provided above each column and asterisks denote statistical significance by t-test comparison between NGF-treated and untreated TrkA SH-SY5Y controls.</p

TrkAIII protects SH-SY5Y cells against ROS-mediated death.

<p>A) Digital fluorescence micrographs demonstrating changes in viability (green = alive; red = dead) in pcDNA, TrkA and TrkAIII SH-SY5Y cells under basal conditions (Control) or treated for 24 hours at 37°C with either 1 µM Rotenone; 250 µM Paraquat; or for 6 hours with 1 µM LY83583, at 37°C (bar = 100 µm). B) Histograms showing differences in the viability of: (I) pcDNA; (II) TrkAI; and (III) TrkAIII SH-SY5Y cells, treated as described above. Results are displayed as mean±s.d percent viability, in three independent experiments performed in duplicate. Mean values are provided above each column and asterisks denote statistical significance by Student’s t-test comparison of Ros-inducer treated and untreated controls. C) Digital fluorescence micrographs demonstrating viability levels (green = alive; red = dead) in untreated TrkAIII SH-SY5Y cells (Control); TrkAIII SH-SY5Y cells treated with either 1 µM CEP-701, 1 µM K252a, 1 µM Gö6976, 100 nM GW441756, 1 µM Rotenone, 250 µM Paraquat or 1 µM LY83583 alone; or pre-incubated with either 1 µM Cep-701, 1 µM K262a, 1 µM Gö6976 or 100 nM GW441756, then treated with either 1 µM Rotenone, 250 µM Paraquat or 1 µM LY83583 in the continuous presence of each respective inhibitor (Cep-701, K262a, Gö6976 or GW441756), (bar = 100 µm). D) Histogram demonstrating differences in TrkAIII SH-SY5Y cell viability in untreated TrkAIII SH-SY5Y cells (Control); TrkAIII SH-SY5Y cells treated with either 1 µM CEP-701, 1 µM K252a, 1 µM Gö6976, 100 nM GW441756, 1 µM Rotenone, 250 µM Paraquat or 1 µM LY83583 alone; or pre-incubated with either 1 µM Cep-701, 1 µM K262a, 1 µM Gö6976 or 100 nM GW441756, then treated with either 1 µM Rotenone, 250 µM Paraquat or 1 µM LY83583 in the continuous presence of each respective inhibitor, as for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094568#pone-0094568-g009" target="_blank">Fig. 9C</a>. Results are displayed as mean±s.d percent viability, in three independent experiments performed in duplicate. Mean values are provided above each column and asterisks denote statistical significance by Student’s t-test (p<0.0001, df = 10) and One-Way ANOVA ((2, 15) p<0.0001), comparing inhibitor alone, ROS-inducer alone and inhibitor plus Ros-inducer groups.</p

TrkAIII promotes mitochondrial hydrogen peroxide production.

<p>Line graph displaying comparative levels of H₂0₂ produced over a 210-minute time course by equivalent protein concentrations (60 µg) of intact purified mitochondria from pcDNA, TrkA and TrkAIII SH-SY5Y cells, in an Amplex Red-based assay, following reaction initiation with 10 mM succinate. Results are displayed as the mean±s.d. relative light units produced in minutes following 10 mM succinate addition, in three independent experiments performed in duplicate (asterisks denote statistical significance by t-test comparison of TrkAIII SH-SY5Y cells to either pcDNA or TrkA SH-SY5Y cells).</p