Results: As compare with vehicle-treated animals, empagliflozin-t

Results: As compare with vehicle-treated animals, empagliflozin-treated OLETF rats showed approximately 1,000-fold increase in

urinary glucose excretion and improved glucose metabolism. Furthermore, empagliflozin significantly decreased blood pressure, which was associated with increases in urinary excretion of sodium. Conclusion: These data suggest that empagliflozin elicits beneficial effects on glucose metabolism and hypertension in salt-treated obese metabolic syndrome rats. WU VIN-CENT1, HUANG TAO-MIN2 1National Taiwan University Hospital; selleck compound 2National Taiwan University Hospital, Yun-Lin Branch Introduction: The incidence rate of acute kidney injury (AKI) in hospitalized patients is increasing. However, relatively little attention has been paid to association of AKI with long-term risk of adverse coronary events. Methods: Our Temozolomide chemical structure study investigated hospitalized patients who recovered from de novo dialysis-requiring AKI between 1999 and 2008. Their data were collected from inpatient claims of the Taiwan National Health Insurance (NHI). We used Cox regression with time-varying covariates to adjust for subsequent chronic kidney disease (CKD) and end-stage renal disease (ESRD) after discharge. Results

were further validated by analysis of a prospectively constructed database. Results: Among the 17,106 acute dialysis patients who were discharged, 4,869 recovered from dialysis-requiring AKI (AKI-recovery group) and were matched with 4,869 non-AKI patients. The incidence rates of coronary events were 19.8 and 10.3 per 1,000 person-years in the AKI-recovery and the non-AKI groups, respectively. AKI-recovery was associated with higher risk of coronary events (hazard ratio (HR), 1.67) and all-cause mortality (HR, 1.67), independent of the effects of subsequent progression of CKD and ESRD. The risk levels of de novo coronary events after hospital discharge were close in those with diabetes alone and AKI alone (p = 0.227). Conclusion: Our study results reveal that AKI with recovery was mafosfamide associated with higher long-term risks of coronary events and death, suggesting that AKI could be added into the list

of criteria identifying patients with high risk of future coronary events. It may be warranted to enhance post-discharge follow-up of renal function, even among patients who have recovered from temporary dialysis. MARBA IAN LEE V. Chong Hua Hospital, Cebu Introduction: Contrast-induced nephropathy is now established as the third most common cause of hospital acute kidney injury after surgery and hypotension. With the increase in numbers of PCI performed in the tertiary hospitals in the country, institution may apply a scoring system that will predict the risk of CIN and dialysis. Hence, this local study was conducted to validate the Mehran score in predicting CIN after PCI and used this scoring system as part of the hospital quality improvement goal.

Using a thioglycollate-induced peritonitis model and an acute as

Using a thioglycollate-induced peritonitis model and an acute as well as chronic lung inflammation model, we demonstrate that Thy-1 plays an important role in the control of leukocyte recruitment at sites of inflammation and in the conditioning of the inflammatory tissue microenvironment. Because Thy-1 displays a species-specific expression Sunitinib in vitro pattern 6, 17, 18, we analysed Thy-1 expression on ECs at sites of inflammation in mice. In healthy lung or healthy peritoneal tissue, Thy-1 was only hardly detectable on few ECs (Fig. 1A and B). In contrast to humans, Thy-1 seems to be slightly expressed

on resting ECs in mice. However, upon induction of inflammation, Thy-1 expression on ECs was massively enhanced (Fig. 1C–F). We found strong Thy-1 expression on ECs of WT mice during lung inflammation, induced by immunization with OVA (Fig. 1D and F). In addition, Thy-1 was expressed on ECs in peritoneal tissue upon induction of inflammation, induced by thioglycollate (Fig. 1C and E). The functional role of Thy-1 in mediating adhesion and transmigration of neutrophils and monocytes was studied in a thioglycollate-induced peritonitis model in Thy-1−/− mice Palbociclib supplier and littermates. Prior

to induction of inflammation, the blood leukocyte count as well as the subset proportions in Thy-1−/− mice and control mice were similar (Table 1). Induction of inflammation by i.p. injection of thioglycollate

induced strong recruitment of leukocytes into the peritoneal cavity (Fig. 2A), which MRIP peaked 24 h after injection. The number of emigrated leukocytes was significantly decreased at 6 and 24 h after the i.p. injection in Thy-1−/− mice, compared to WT littermates. At later time points, no significant differences in the influx of inflammatory cells into the peritoneal cavity in Thy-1−/− and WT mice were detected (Fig. 2A). Analysis of extravasated cells 24 h after thioglycollate injection revealed that the recruitment of neutrophils and monocytes was significantly reduced in Thy1−/− mice (Fig. 2B). Lymphocytes were only marginally detectable. Histological analysis of peritoneal tissue confirmed these data. In contrast to those in Thy-1−/− mice, inflammatory cells in WT mice could be observed by H&E staining (Fig. 2C and D). Using immunohistochemical staining, a clear infiltration of CD11b+ cells was detected in the peritoneal tissue of WT mice (Fig. 2G). In Thy1−/− mice the infiltration was significantly inhibited (Fig. 2H). Further analysis of these infiltrates revealed that F4/80+macrophages (Fig. 2I and J) and Gr-1+neutrophil granulocytes (Fig. 2K and L) were decreased in peritoneal tissue of Thy1−/− mice. Taken together, Thy-1 plays an important role in the recruitment of neutrophils and monocytes during thioglycollate-induced peritoneal inflammation.

25 There were no significant

differences in CD161 express

25 There were no significant

differences in CD161 expression on NKT cells between all four groups. The NKT cells can became activated during a variety of infections and inflammatory responses,26 but HLA-DR expression was not significantly different between study groups. The NKT cells are activated in response to the glycolipid antigen α-GalCer and antigen presentation occurs through CD1d.7 The ELISPOT assay is a sensitive method for detecting and quantifying antigen-reactive cells in a population of lymphocytes with multiple Tanespimycin order specificities.27 To determine the frequency of α-GalCer-reactive cells, we analysed PBMCs in a single-colour ELISPOT assay using the DX-α-GalCer stimulation method.28 Cells secreting IFN-γ and IL-4 were detected from all four groups. Results were expressed in spot-forming units (SFU) per million cells. We demonstrated that, when stimulated with specific antigen α-GalCer, PBMC from co-infected patients showed greater secretion of IFN-γ (median 10 SFU, IQR 3–14) compared with leprosy mono-infected Akt inhibitor patients (median 0 SFU, IQR 0.0–5.5), P < 0.05 (Fig. 3a). No difference in IL-4 secretion by NKT cells was detected between the groups

(Fig. 3b). However, IFN-γ frequencies in co-infected patients were positively correlated with the percentage of CD161+ NKT cells (r = 0.81, P = 0.02) (data not shown). In this study, we demonstrated that patients co-infected with M. leprae and HIV-1 had lower frequencies of NKT cells in

peripheral blood than healthy subjects and HIV-1-mono-infected patients. Although many studies have attributed beneficial anti-pathogen Resveratrol responses to NKT cells, they have also been implicated in detrimental immune responses that lead to immunopathology and disease.8 In HIV-1-infected individuals, the frequency of NKT cells is markedly reduced in peripheral blood compared with uninfected controls,2,29,30 and this loss of NKT cells could lead to autoimmunity or to autoimmune-like conditions. Diminished NKT cell-mediated anti-tumour responses could also contribute to increased incidence of infection-related tumours such as Kaposi sarcoma and non-Hodgkin’s lymphoma in AIDS patients.24 In another human retrovirus infection, lower numbers of circulating Vα24+ Vβ11+ NKT cells in individuals infected with human T lymphotropic virus type 1 (HTLV-1) have been demonstrated.31 Natural killer T cells also participate in host defence against mycobacterial infection. Some groups have described lower numbers of NKT cells in peripheral blood of patients with mycobacterial infections.32,33 There are significantly lower percentages of circulating NKT cells in patients with active pulmonary tuberculosis than in subjects uninfected with Mycobacterium tuberculosis33 and these cells become activated upon infection.32 Activation of NKT cells in M.

Gregory Tsay (Taiwan) suggested that RNA interference targeting I

Gregory Tsay (Taiwan) suggested that RNA interference targeting IL-10 is an effective strategy to silence the IL-10 pathway and has therapeutic potential that could be useful in the management of

SLE and possibly other immune-mediated disorders. Chetan Chitnis (India) and Nirbhay Kumar (USA) presented their research work which is moving towards the development of a vaccine against malaria. Sunil Arora (India) highlighted one of the reasons for the success of antiviral therapy in chronic hepatitis C infection which relates to the functional status of myeloid dendritic cells (mDCs) in these patients. The sixth symposium covered the broad theme of autoimmunity, featuring discussions on the genetic and functional aspects of autoimmune diseases. Chella David (USA) and Kamal Moudgil (USA) unraveled novel aspects of autoimmune pathogenesis. The role of complement in RA and SLE, with a main focus on B-cell functions, was highlighted by Anna Erdei (Hungary). Veena Taneja (USA) described the importance of the interaction between the HLA gene products and gut microbes in the development selleck inhibitor of rheumatoid arthritis. Moncef Zouali

(France) and Rahul Pal (India) gave an overview of new pathways and new targets in autoimmune diseases. The theme-based symposium of the last day of the Congress featured talks on immune mechanisms underlying infectious diseases. In this session, Miles Davenport (Australia) explained that the CD8+ T-cell response to Rucaparib supplier viral infection involves the recruitment of multiple different T-cell clonotypes, each bearing a unique T-cell receptor. Nageshwar Rao (India) discussed the mechanism leading to immune suppression during the progression of leprosy from tuberculoid to lepromatous, namely the overproduction of CD4+CD25+/FoxP3+ cells. Padmini Salgame (USA) showed that the T helper and regulatory response induced by helminths could modulate the host protective response against M. tuberculosis. Suresh Mahalingam (Australia) highlighted the link between viral infections and inflammatory disease focusing on the Chikungunia virus. Symposium 8 started with a theme focused on infections, immunodeficiencies and HIV. The first

speaker of this symposium, Rose Ffrench (Australia), presented data on the production of interferon-lambda in chronic HCV infection. This was followed by Gurvinder Kaur (India) who discussed the genetic architecture of HIV infection particularly in relation to disease susceptibility, progression and transmission. Gurvinder Kaur’s lecture focused on three sets of immuno-regulatory molecules and their genetic polymorphisms, namely HLA, chemokines and cytokine gene polymorphisms. Stanley Schwartz (USA) linked the application of nanotechnology to HIV infection and Madhu Vajpayee (India) discussed the abnormal behavior of T cells in HIV. Ashok Kumar (USA) and Nirupama Trehanpati (India) focused on the immunology of ocular infectious disease and HBV infection in newborns respectively.

However, increased levels of IL-10 could contribute to increased

However, increased levels of IL-10 could contribute to increased susceptibility towards bacterial infections. see more Furthermore, several studies have demonstrated the influence of the PKB/Akt

signaling cascade on the LPS-driven IL-10 production [35-38]. In analogy to our study (Fig. 5C and Supporting Information Fig. 2D), Schaffer et al. [38] showed that LPS stimulation of human PBMCs after mTOR inhibition resulted in reduced IL-10 secretion, whereas TNF levels were not affected. Furthermore, inhibition of PI3K or mTOR and subsequent LPS-stimulation of human monocytes and dendritic cells and murine macrophages yielded similar results: IL-10 synthesis was abolished and IL-12 production increased [33, 35-37, 39]. The counter-regulation of IL-10 and IL-12 is most likely attributable to IL-10-mediated inhibition of IL-12 production as previously demonstrated in human monocytes [40]. We therefore speculate that IRAK4-silenced selleck inhibitor monocytes resemble rapamycin-treated DCs that display a similar cytokine pattern and defective allogenic T-cell stimulatory capacity [39]. IRAK4-deficiency and mTOR inhibitors

might, thus, counteract the tolerogenic properties of PKB/Akt signaling in innate immune cells resulting inflammation and stomatitis, an important side effect of these drugs [41, 42]. Nevertheless, it remains elusive how TLR signaling is connected to the PI3K/PKB/Akt cascade and how IRAK4 is engaged in this process. In co-immunoprecipitation experiments there was no evidence for a direct

interaction of IRAK4 with PI3K or PKB/Akt (data not shown). However, PI3K is recruited upon TLR activation [43-45]: the cytosolic domain of TLR2 interacted with the regulatory polypeptide p85 of PI3K, resulting in PKB/Akt activation [43] and LPS-induced formation of a TLR4/MyD88/PI3K multiprotein signalosome, which lead to Akt-triggered cytokine secretion in mouse macrophages [44]. Most importantly, a direct interaction of MyD88 with the p85 subunit of PI3K was demonstrated via co-immunoprecipitation, most likely involving an YXXM motif in the TIR domain of MyD88 [44, 45]. Thus, MyD88 could be directly linked to the PI3K/PKB/Akt signaling pathway. We can, however, only speculate that the absence of IRAK4 makes additional MyD88 Avelestat (AZD9668) binding sites available for PI3K and thereby favors PKB/Akt signaling. Binding of IRAK4 could, thus, interfere with MyD88-PI3K interaction by inducing a conformational change in the MyD88 molecule or by competitively blocking MyD88-binding sites for PI3K. Similarly, we cannot exclude that a so far unknown signaling pathway downstream of IRAK4 negatively regulates PKB/Akt signaling. Future work is needed to clarify this matter. By suppressing IL-10 secretion and FoxO3a transcription factor activation, IRAK4 switches the cell from a tolerogenic to a pro-inflammatory phenotype.

1D) This partial RING domain is insufficient to confer E3 ubiqui

1D). This partial RING domain is insufficient to confer E3 ubiquitin ligase activity on viral Pellino since a recombinant form of the latter failed to catalyse the in vitro generation of polyubiquitin chains in the presence of E1 and E2 enzymes, whereas the mammalian member Pellino3S shows strong catalytic activity (Fig.

1E). Western immunoblotting using an anti-myc Tofacitinib chemical structure antibody shows that the lack of activity of viral Pellino relative to Pellino3 cannot be attributed to differences in protein quantity since both proteins show comparable levels of immunoreactivity. Interestingly, viral Pellino has a mobility corresponding to its predicted size of 25.4 kDa but it also shows a fainter immunoreactive band of slower electrophoretic mobility. The identity of this protein is unknown but its lack of reactivity with the anti-ubiquitin

antibody excludes selleck chemical the possibility of the protein being modified by ubiquitination. The above analysis suggests that viral Pellino resembles its mammalian counterparts in containing a core FHA domain but differs in lacking both a wing appendage to the FHA domain and a functional RING-like motif. The emerging roles of Pellino proteins in TLR signalling coupled to the discovery of a viral homolog prompted studies on the ability of viral Pellino to regulate TLR signal transduction. Viral Pellino is encoded by the genome of MsEPV and given that the natural host of MsEPV is insect cells, the highly AT-rich sequence of the viral Pellino gene reflects an adaptation to this environment. In order

to ensure expression of viral Pellino in both insect and human cells, a form of the gene was chemically synthesised with codon sequences optimised for recognition by human translation machinery. This involved replacing As or Ts in the third position of each codon with a G or C, without altering the amino acid sequence of the translated protein. Such an approach was previously shown to enhance expression of poxviral genes in human cells 24. We initially Thiamine-diphosphate kinase assessed the effects of viral Pellino on Toll signalling in macrophage-like Drosophila S2 cells. A myc-tagged version of the viral protein showed uniform cytoplasmic distribution after transfection in these cells (Fig. 2A). The effects of increasing levels of viral Pellino expression on signalling by the Toll ligand C-106 was then assessed (Fig. 2B). C-106 is the active C-terminal fragment of the Spätzle protein and induced activation of a firefly luciferase reporter under the control of the drosomycin promoter. Toll signalling can induce expression of this antimicrobial peptide through the Rel family transactivators Dorsal and Dif. Thus, the activation of the drosomycin promoter was an especially relevant readout for Toll signalling in the present studies in light of the demonstration that Drosophila Pellino plays a key role in driving expression of drosomycin 13.

Treatment with an anti-IL-17 mAb protected NOD mice against diabe

Treatment with an anti-IL-17 mAb protected NOD mice against diabetes only when performed at late stage of disease development 27. Although learn more it is clear that Th17 cells play an important role in some autoimmune disease models, their precise role in diabetes remains to be elucidated. All these observations on the role of IL-17 and iNKT cells in autoimmune diseases led us to characterize iNKT17 cells in the NOD mouse and to investigate whether these

cells play a pathogenic role in diabetes. To investigate the role of iNKT17 cells in type 1 diabetes, we have compared the frequency and absolute number of these cells in NOD and C57BL/6 mice. C57BL/6 mice were used as the control mice, since they develop neither diabetes nor other autoimmune pathologies. iNKT17 cells were analyzed in the thymus, spleen, inguinal LNs (ILNs) and PLNs. ILNs were used as control tissue since they are enriched in iNKT17 cells 28. IL-17 production by iNKT cells was detected after CD1d-αGalCer tetramer staining and stimulation with phorbolmyristyl acetate (PMA) and ionomycin (Fig. 1A). As previously shown in C57BL/6 mice,

iNKT17 cells do not express the NK1.1 marker. These cells are also NK1.1− in NK1.1 congenic NOD mice used for this analysis (Fig. 1B). Interestingly, iNKT17 cell frequency was four to six-fold increased in NOD mice as compared PS-341 order with C57BL/6 mice (Fig. 1B and C). This difference was also observed in terms of absolute number (Fig. 1D). Of note, in PLNs of NOD mice, iNKT17 cells represent 13% of total iNKT cells compared with only 2% in C57BL/6 mice. The high frequency and absolute number in PLNs of NOD mice suggest that iNKT17 cells could

play a role in the development of type 1 diabetes. Previous studies have shown that unlike Th17 cells, iNKT17 cells are generated during thymic differentiation 19. iNKT cell maturation can be divided in three differentiation stages; stage 1 (CD44− NK1.1−), stage 2 (CD44+ NK1.1− CD4− or CD4+) and stage 3 (CD44+ NK1.1+). We have analyzed the expression of genes usually associated with the iNKT17 lineage in thymic iNKT cells. Quantitative-PCR data show that il-17a gene is mainly transcribed in stage 2 CD4− iNKT cells and to a lesser extent in Ribonucleotide reductase stage 1 and stage 2 CD4+ iNKT cells (Fig. 1D). In agreement with our results obtained by intracellular IL-17 staining, IL-17A mRNA level is increased (10-fold) in stage 2 CD4− iNKT cells from NOD as compared with C57BL/6 mice. Analysis of mRNA encoding RORγt, which is required for iNKT17 cell differentiation 21, revealed its high expression in the stage 2 CD4− iNKT cells and 3-fold increased in NOD mice. IL-23R is constitutively expressed by iNKT17 cells 20, and its expression is high in stage 2 CD4− iNKT cells, however, there is no significant difference between NOD and C57BL/6 mice.

[29] These results led to the hypothesis that DM functions as a g

[29] These results led to the hypothesis that DM functions as a general purpose peptide exchange catalyst.[30] However, experiments examining the activity

of DM during peptide loading in vivo suggested that DM also has the ability to act as an MHCII-specific chaperone by stabilizing empty MHCII under low pH conditions.[31-33] In contrast to the expected MK-8669 1 : 1 ratio, quantitative immunoblot analysis demonstrates a 5 : 1 molar ratio of MHCII to DM, which is more consistent with a catalytic role for DM than simply chaperone-like.[34] In the attempt to reconcile DM’s catalytic activity on the dissociation of the bound peptide with the one facilitating loading of peptide into the MHCII groove, many groups began to investigate the mechanism by which DM molecules interact with MHCII. Unfortunately the crystal structures of DM or the murine H2-M [35] did not reveal any obvious structural features that SAHA HDAC research buy might explain peptide exchange activity for either molecule. Clearly, an association of DM to DR appeared to be required, as DM/MHCII complexes could be immunoprecipitated from solubilized cells under low pH conditions.[36] Indeed, the altered conformations of both MHCII and DM induced by low pH may favour binding.[37] To date,

any attempt to co-crystallize MHCII/DM complexes has failed, but it now appears likely that the lateral face of the MHCII molecule near the N-terminus of the bound peptide is the site of interaction (Fig. 1).[38-40] The structural studies of the DM/MHCII interaction have not been sufficient Protirelin to outline a conclusive mechanism of DM activity. Several works have been published

in which the focus was on determining the characteristics that make a pMHCII complex susceptible to DM-mediated peptide release. The initial hypothesis postulated that the intrinsic dissociation rate of the complex was directly related to its susceptibility to DM-mediated exchange, and the factor by which the DM-catalysed rate constant for peptide release exceeded the rate constant of the uncatalysed reaction was indicated as j factor.[29] The observation that the j factor was constant for complexes with different off-rates suggested that DM promotes peptide release by destabilizing sequence-independent interactions, such as the H-bond network. Indeed, several works have indicated the H-bond network as a viable target of DM activity, possibly promoting or stabilizing a form of the MHCII in which one or more of the H-bonds from the peptide main chain to the MHCII are broken.[41, 42] In particular, it was proposed that DM specifically targets the H-bond formed by the conserved histidine at position β81 in MHCII molecules.

Systemic autoimmune diseases can be modeled in transgenic mice ha

Systemic autoimmune diseases can be modeled in transgenic mice harboring defects in DC apoptosis 10 but not in mice with apoptosis defects in T and B cells 11–13. Our study shows that in addition to the dogma of DC apoptosis as a mechanism to eliminate activated DC to prevent hyperactivation of the immune response, DC apoptosis also plays an

active role in induction and maintenance of tolerance through induction of Treg, whereby defects in DC apoptosis may trigger autoimmunity. High levels of spontaneous DC apoptosis have also been observed in breast cancer patients, with its significance being unclear 15, 16. Our study indicates that DC apoptosis in cancer patients may play a role in suppressing immune responses against the tumor by inducing immunosuppression and tolerance. Therefore, prevention selleck chemicals llc of DC apoptosis may enhance the therapeutic

effects of chemotherapy in tumor AZD3965 eradication 15, 16. Our findings may also represent a therapeutic approach in the prevention of unwanted immune responses in autoimmune diseases and transplantation along with inhibition of DC apoptosis to assist in tumor eradication. C57BL/6 mice were purchased from Charles River Laboratories (St. Constant, QC) and maintained as per guidelines of SickKids animal facilities. All the animal studies were reviewed and approved by the SickKids Institutional Committee for humane use of laboratory animals. OT-II mice were purchased from Jackson Laboratories (Bar Harbor, ME). The following antibodies were purchased from eBioscience (San Diego, CA): CD11c PE, CD86 PE, CD80 PE, MHC II PE, IL-10 Alexa647, IL-12 APC, IL-17 PE, Foxp3 PE along with neutralizing

IL-4 and IFN-γ Ab, and the following from BD Biosciences (Mississauga, ON): CD11c-FITC, CD4-FITC and CD3-PE. Anti-TGF-β neutralizing Ab (MAB1835) was obtained from R&D Systems (Minneapolis, MN). Isotype control IgG were obtained from eBioscience and/or Florfenicol Serotec (Raleigh, NC). CFSE was obtained from Molecular Probes (Burlington, ON); BrdU, OVA, cytochalasin D, rapamycin and PI were obtained from Sigma-Aldrich (Oakville, ON). GM-CSF was obtained from R&D Systems. IL-6 and TGF-β were obtained from Peprotech (Rocky Hill, NJ). Bone marrow cells were isolated from tibia and femurs of adult mice and cultured in the presence of GM-CSF for 7 days as described previously 34. DC were harvested and stained with 1 μM CFSE as described previously 35. Naïve CD4+CD25–CD62L+ T cells were isolated from spleens of mice using CD4+CD62L+ naïve T-cell isolation kit in conjunction with MACS columns from Miltenyi Biotec (Auburn, CA), following the manufacturer’s instructions. DC were cultured on a six-well dish and irradiated for 2 min with a UV transilluminator, with a peak intensity of 9000 mW/cm2 at the filter surface and a peak emission of 313 nm.

However, in contrast to ALS, the number of Gems does not decrease

However, in contrast to ALS, the number of Gems does not decrease in the spinal motor neurons in other motor neuron diseases.[34] Thus, in human spinal motor neurons, the nonspecific alteration of Gems resulting from the suppression of transcriptional activity is less likely. Therefore, we speculate that the alteration of TDP-43 directly decreases the number of Gems. Another important question is how TDP-43 is associated with the formation of Gems. Two hypotheses have been proposed for the formation of nuclear bodies: (i) ordered assembly

Dactolisib cost of the component proteins; or (ii) stochastic assembly, in which component proteins accumulate in an unordered manner at specific RNA or the complex of core proteins.[27-29, 44, 45] Although the process of how nuclear bodies are formed remains unclear, there are several indispensable CP-868596 supplier component

proteins in each body. Thus, two possible molecular mechanisms exist for decreasing the number of Gems by depletion of TDP-43: (i) the depletion of TDP-43 alters the mRNA of the component proteins of Gem; or (ii) TDP-43 directly contributes to the formation of Gems, such that its depletion results in fewer Gems. With regard to the first possibility, it has been reported that TDP-43 regulates the alternative splicing of SMN. The depletion of TDP-43 increased the SMN splicing variant excluding exon 7 in a reporter system.[46] The SMN excluding exon 7 is less stable than SMN with exon 7, resulting in less SMN product.[47] Indeed, we found that the amount of SMN proteins decreased due to the depletion of TDP-43.[34] However, we were unable to confirm the increase in the SMN splicing variants excluding exon 7 in intrinsic SMN mRNA by depletion of TDP-43. Instead of the alteration of splicing variants, we found that the SMN mRNA decreased in the

cells with depleted TDP-43, suggesting that the depletion of TDP-43 induces additional splicing, and the splicing isoform may be less stable than canonical SMN mRNA. However, we were unable to detect the additional splicing variants, which may contribute to the reduced amount of SMN mRNA. Moreover, researchers have not fully evaluated whether the SMN protein Tau-protein kinase or mRNA are reduced in tissues affected with ALS.[48] Therefore, although the intrinsic SMN protein is reduced in cultured cells with the depletion of TDP-43, it is not clear that this is the mechanism underlying the reduction of SMN in tissue affected by ALS. Next, we hypothesized that TDP-43 binds to the component proteins of Gem and increases their stability. Indeed, the protein–protein interaction between TDP-43 and SMN has been reported in a forced expression system,[9, 37, 49] although the result is controversial.[34] In addition, comprehensive analysis of binding proteins to TDP-43 using mass spectrometry failed to identify SMN or other component proteins of Gem.