Gene therapy for glycogen storage diseases.

Glycogen storage disorders (GSDs) are inherited disorders of metabolism resulting from the deficiency of individual enzymes involved in the synthesis, transport, and degradation of glycogen. This literature review summarizes the development of gene therapy for the GSDs. The abnormal accumulation of glycogen and deficiency of glucose production in GSDs lead to unique symptoms based upon the enzyme step and tissues involved, such as liver and kidney involvement associated with severe hypoglycemia during fasting and the risk of long-term complications including hepatic adenoma/carcinoma and end stage kidney disease in GSD Ia from glucose-6-phosphatase deficiency, and cardiac/skeletal/smooth muscle involvement associated with myopathy +/- cardiomyopathy and the risk for cardiorespiratory failure in Pompe disease. These symptoms are present to a variable degree in animal models for the GSDs, which have been utilized to evaluate new therapies including gene therapy and genome editing. Gene therapy for Pompe disease and GSD Ia has progressed to Phase I and Phase III clinical trials, respectively, and are evaluating the safety and bioactivity of adeno-associated virus vectors. Clinical research to understand the natural history and progression of the GSDs provides invaluable outcome measures that serve as endpoints to evaluate benefits in clinical trials. While promising, gene therapy and genome editing face challenges with regard to clinical implementation, including immune responses and toxicities that have been revealed during clinical trials of gene therapy that are underway. Gene therapy for the glycogen storage diseases is under development, addressing an unmet need for specific, stable therapy for these conditions.

Successful AAV8 readministration: Suppression of capsid-specific neutralizing antibodies by a combination treatment of bortezomib and CD20 mAb in a mouse model of Pompe disease.

BACKGROUND: A major challenge to adeno-associated virus (AAV)-mediated gene therapy is the presence of anti-AAV capsid neutralizing antibodies (NAbs), which can block viral vector transduction even at very low titers. In the present study, we examined the ability of a combination immunosuppression (IS) treatment with bortezomib and a mouse-specific CD20 monoclonal antibody to suppress anti-AAV NAbs and enable readministration of AAV vectors of the same capsid in mice. METHODS: An AAV8 vector (AAV8-CB-hGAA) that ubiquitously expresses human α-glucosidase was used for initial gene therapy and a second AAV8 vector (AAV8-LSP-hSEAP) that contains a liver-specific promoter to express human secreted embryonic alkaline phosphatase (hSEAP) was used for AAV readministration. Plasma samples were used for determination of anti-AAV8 NAb titers. Cells isolated from whole blood, spleen, and bone marrow were analyzed for B-cell depletion by flow cytometry. The efficiency of AAV readministration was determined by the secretion of hSEAP in blood. RESULTS: In näive mice, an 8-week IS treatment along with AAV8-CB-hGAA injection effectively depleted CD19+ B220+ B cells from blood, spleen, and bone marrow and prevented the formation of anti-AAV8 NAbs. Following administration of AAV8-LSP-hSEAP, increasing levels of hSEAP were detected in blood for up to 6 weeks, indicating successful AAV readministration. In mice pre-immunized with AAV8-CB-hGAA, comparison of IS treatment for 8, 12, 16, and 20 weeks revealed that the 16-week IS treatment demonstrated the highest plasma hSEAP level following AAV8-LSP-hSEAP readministration. CONCLUSIONS: Our data suggest that this combination treatment is an effective IS approach that will allow retreatment of patients with AAV-mediated gene therapy. A combination IS treatment with bortezomib and a mouse-specific CD20 monoclonal antibody effectively suppressed anti-AAV NAbs in naïve mice and in mice with pre-existing antibodies, allowing successful readministration of the same AAV capsid vector.

Metal oxide-based macroporous ordered double affinity molecularly imprinted polymer for specific separation and enrichment of glycoprotein from food samples: a co-modification of DMSA and boronate affinity.

Metal oxide-based macroporous ordered double affinity molecularly imprinted polymers (D-MIPs) were developed as solid phase extraction (SPE) adsorbents for the specific identification of ovalbumin (OVA) under physiological pH conditions prior to ultraviolet visible (UV-vis) spectrophotometric detection. Herein, macroporous alumina (MA) was used as a matrix; dimercaptosuccinic acid (DMSA) and 3-aminophenylboric acid (APBA) were employed as dual-functional monomers; APBA is a self-polymerizing monomer. The effects of synthesis conditions, SPE conditions as well as selectivity, reproducibility, and reusability were studied. The co-modification of DMSA and boronate affinity renders the adsorbent exhibiting a high adsorption capacity (114.4 mg g-1) and short equilibrium time (30 min). The surface imprinting technology causes the adsorbent to have high selectivity towards OVA. The OVA recovery range is 91.1-99.6%. This study provides a promising method for the enrichment of OVA and other cis-diol-containing analytes in complex biological samples. A novel metal oxide-based macroporous ordered nanoparticle with a combination of DMSA and boronate affinity was successfully prepared for specific separation and enrichment of glycoprotein from complex biological samples.

Gene therapy for glycogen storage diseases.

The focus of this review is the development of gene therapy for glycogen storage diseases (GSDs). GSD results from the deficiency of specific enzymes involved in the storage and retrieval of glucose in the body. Broadly, GSDs can be divided into types that affect liver or muscle or both tissues. For example, glucose-6-phosphatase (G6Pase) deficiency in GSD type Ia (GSD Ia) affects primarily the liver and kidney, while acid α-glucosidase (GAA) deficiency in GSD II causes primarily muscle disease. The lack of specific therapy for the GSDs has driven efforts to develop new therapies for these conditions. Gene therapy needs to replace deficient enzymes in target tissues, which has guided the planning of gene therapy experiments. Gene therapy with adeno-associated virus (AAV) vectors has demonstrated appropriate tropism for target tissues, including the liver, heart and skeletal muscle in animal models for GSD. AAV vectors transduced liver and kidney in GSD Ia and striated muscle in GSD II mice to replace the deficient enzyme in each disease. Gene therapy has been advanced to early phase clinical trials for the replacement of G6Pase in GSD Ia and GAA in GSD II (Pompe disease). Other GSDs have been treated in proof-of-concept studies, including GSD III, IV and V. The future of gene therapy appears promising for the GSDs, promising to provide more efficacious therapy for these disorders in the foreseeable future.

Characterization of liver GSD IX γ2 pathophysiology in a novel Phkg2-/- mouse model.

INTRODUCTION: Liver Glycogen Storage Disease IX is a rare metabolic disorder of glycogen metabolism caused by deficiency of the phosphorylase kinase enzyme (PhK). Variants in the PHKG2 gene, encoding the liver-specific catalytic γ2 subunit of PhK, are associated with a liver GSD IX subtype known as PHKG2 GSD IX or GSD IX γ2. There is emerging evidence that patients with GSD IX γ2 can develop severe and progressive liver disease, yet research regarding the disease has been minimal to date. Here we characterize the first mouse model of liver GSD IX γ2. METHODS: A Phkg2-/- mouse model was generated via targeted removal of the Phkg2 gene. Knockout (Phkg2-/-, KO) and wild type (Phkg2+/+, WT) mice up to 3 months of age were compared for morphology, Phkg2 transcription, PhK enzyme activity, glycogen content, histology, serum liver markers, and urinary glucose tetrasaccharide Glcα1-6Glcα1-4Glcα1-4Glc (Glc4). RESULTS: When compared to WT controls, KO mice demonstrated significantly decreased liver PhK enzyme activity, increased liver: body weight ratio, and increased glycogen in the liver, with no glycogen accumulation observed in the brain, quadricep, kidney, and heart. KO mice demonstrated elevated liver blood markers as well as elevated urine Glc4, a commonly used biomarker for glycogen storage disease. KO mice demonstrated features of liver structural damage. Hematoxylin & Eosin and Masson's Trichrome stained KO mice liver histology slides revealed characteristic GSD hepatocyte architectural changes and early liver fibrosis, as have been reported in liver GSD patients. DISCUSSION: This study provides the first evidence of a mouse model that recapitulates the liver-specific pathology of patients with GSD IX γ2. The model will provide the first platform for further study of disease progression in GSD IX γ2 as well as for the evaluation of novel therapeutics.

Elevated interleukin-37 associated with tophus and pro-inflammatory mediators in Chinese gout patients.

INTRODUCTION: Interleukin-37(IL-37), a natural inhibitor of innate immunity, has been identified to protect against various inflammatory diseases, including monosodium urate (MSU)-induced inflammation. However, the association of IL-37 with clinical indexes and pro-inflammatory mediators in gout patients remains unclear. The aim of this study was to determine IL-37 level in hyperuricemia and gout patients with or without tophus, and to investigate the correlations of IL-37 with clinical indexs such as Uric Acid (UA), CRP(C-reactive protein), Creatinine Clearance Rate (Ccr), Erythrocyte Sedimentation Rate (ESR) and so on, as well as with the pro-inflammatory mediators in serum including Interleukin-1ß(IL-1ß), Interleukin-6(IL-6) and Interleukin-18(IL-18) from gout patients. METHODOLOGY: The serum levels of IL-37, IL-1ß, IL-6 and IL-18 levels in serum of gout patients were determined by ELISA; the correlations between IL-37 and clinical values or pro-inflammatory mediators in serum of gout were analyzed by Spearman correlation test. RESULTS: The serum levels of IL-37 were higher in active gout patients than inactive gout patients and HCs, especially in active gout patients with tophus. No significant difference was observed in serum IL-37 levels between hyperuricemia and normal controls. IL-1ß, IL-6 and IL-18 levels were significant elevated in gout patients with tophus than those without tophus; Serum IL-37 were positively correlated with CRP and ESR, as well as with IL-1ß, IL-6 and IL-18, negatively correlated with Ccr, and not correlated with UA, creatinine (Cr) and triglyceride (TG) in gout patients. CONCLUSIONS: IL-37 increased in gout patients positively associated CRP and ESR, as well as with proinflammatory mediators IL-1ß, IL-6, IL-18, the presence of tophus and chronic kidney disease in gout. It may be a novel marker for predicting this pathology.

Transcriptomic and Proteomic Analysis of Clear Cell Foci (CCF) in the Human Non-Cirrhotic Liver Identifies Several Differentially Expressed Genes and Proteins with Functions in Cancer Cell Biology and Glycogen Metabolism.

Clear cell foci (CCF) of the liver are considered to be pre-neoplastic lesions of hepatocellular adenomas and carcinomas. They are hallmarked by glycogen overload and activation of AKT (v-akt murine thymoma viral oncogene homolog)/mTOR (mammalian target of rapamycin)-signaling. Here, we report the transcriptome and proteome of CCF extracted from human liver biopsies by laser capture microdissection. We found 14 genes and 22 proteins differentially expressed in CCF and the majority of these were expressed at lower levels in CCF. Using immunohistochemistry, the reduced expressions of STBD1 (starch-binding domain-containing protein 1), USP28 (ubiquitin-specific peptidase 28), monad/WDR92 (WD repeat domain 92), CYB5B (Cytochrome b5 type B), and HSPE1 (10 kDa heat shock protein, mitochondrial) were validated in CCF in independent specimens. Knockout of Stbd1, the gene coding for Starch-binding domain-containing protein 1, in mice did not have a significant effect on liver glycogen levels, indicating that additional factors are required for glycogen overload in CCF. Usp28 knockout mice did not show changes in glycogen storage in diethylnitrosamine-induced liver carcinoma, demonstrating that CCF are distinct from this type of cancer model, despite the decreased USP28 expression. Moreover, our data indicates that decreased USP28 expression is a novel factor contributing to the pre-neoplastic character of CCF. In summary, our work identifies several novel and unexpected candidates that are differentially expressed in CCF and that have functions in glycogen metabolism and tumorigenesis.

Therapeutic Benefit of Autophagy Modulation in Pompe Disease.

The complexity of the pathogenic cascade in lysosomal storage disorders suggests that combination therapy will be needed to target various aspects of pathogenesis. The standard of care for Pompe disease (glycogen storage disease type II), a deficiency of lysosomal acid alpha glucosidase, is enzyme replacement therapy (ERT). Many patients have poor outcomes due to limited efficacy of the drug in clearing muscle glycogen stores. The resistance to therapy is linked to massive autophagic buildup in the diseased muscle. We have explored two strategies to address the problem. Genetic suppression of autophagy in muscle of knockout mice resulted in the removal of autophagic buildup, increase in muscle force, decrease in glycogen level, and near-complete clearance of lysosomal glycogen following ERT. However, this approach leads to accumulation of ubiquitinated proteins, oxidative stress, and exacerbation of muscle atrophy. Another approach involves AAV-mediated TSC knockdown in knockout muscle leading to upregulation of mTOR, inhibition of autophagy, reversal of atrophy, and efficient cellular clearance on ERT. Importantly, this approach reveals the possibility of reversing already established autophagic buildup, rather than preventing its development.

Starch Binding Domain-containing Protein 1 Plays a Dominant Role in Glycogen Transport to Lysosomes in Liver.

A small portion of cellular glycogen is transported to and degraded in lysosomes by acid α-glucosidase (GAA) in mammals, but it is unclear why and how glycogen is transported to the lysosomes. Stbd1 has recently been proposed to participate in glycogen trafficking to lysosomes. However, our previous study demonstrated that knockdown of Stbd1 in GAA knock-out mice did not alter lysosomal glycogen storage in skeletal muscles. To further determine whether Stbd1 participates in glycogen transport to lysosomes, we generated GAA/Stbd1 double knock-out mice. In fasted double knock-out mice, glycogen accumulation in skeletal and cardiac muscles was not affected, but glycogen content in liver was reduced by nearly 73% at 3 months of age and by 60% at 13 months as compared with GAA knock-out mice, indicating that the transport of glycogen to lysosomes was suppressed in liver by the loss of Stbd1. Exogenous expression of human Stbd1 in double knock-out mice restored the liver lysosomal glycogen content to the level of GAA knock-out mice, as did a mutant lacking the Atg8 family interacting motif (AIM) and another mutant that contains only the N-terminal 24 hydrophobic segment and the C-terminal starch binding domain (CBM20) interlinked by an HA tag. Our results demonstrate that Stbd1 plays a dominant role in glycogen transport to lysosomes in liver and that the N-terminal transmembrane region and the C-terminal CBM20 domain are critical for this function.

Alglucosidase alfa enzyme replacement therapy as a therapeutic approach for a patient presenting with a PRKAG2 mutation.

OBJECTIVE: PRKAG2 syndrome, an autosomal dominant disorder, is characterized by severe infantile hypertrophic cardiomyopathy and heart rhythm disturbances to cases with a later presentation and a spectrum of manifestations including cardiac manifestations, myopathy and seizures. The cardiac features of PRKAG2 resemble the cardiac manifestations of Pompe disease. We present a patient who was initially diagnosed with Pompe disease and treated with alglucosidase-alfa enzyme replacement therapy (ERT); however, he was eventually diagnosed to carrying a PRKAG2 pathogenic gene mutation; he did not have Pompe disease instead he was a carrier for the common adult leaky splice site mutation in the GAA gene. CASE REPORT: At 2.5months, the patient had hypotonia/generalized muscle weakness, a diagnosis of non-classic infantile Pompe disease was made based on low acid alpha-glucosidase activity and the patient started on ERT at 11months. However, 1month later, the patient began to have seizures. As the patient's medical history was somewhat unusual for infantile Pompe disease, further evaluation was initiated and included a glycogen storage disease sequencing panel which showed that the patient had a pathogenic mutation in PRKAG2 which had been reported previously. ERT was discontinued and patient had a progression of motor deficits. ERT was reinitiated by the treating physician, and a clinical benefit was noted. CONCLUSION: This report outlines the benefits of ERT with alglucosidase alfa in a patient with PRKAG2 syndrome, the decline in his condition when the ERT infusions were discontinued, and the significant positive response when ERT was reinitiated.

Adjunctive ß2-agonists reverse neuromuscular involvement in murine Pompe disease.

Pompe disease has resisted enzyme replacement therapy with acid α-glucosidase (GAA), which has been attributed to inefficient cation-independent mannose-6-phosphate receptor (CI-MPR) mediated uptake. We evaluated ß2-agonist drugs, which increased CI-MPR expression in GAA knockout (KO) mice. Clenbuterol along with a low-dose adeno-associated virus vector increased Rotarod latency by 75% at 4 wk, in comparison with vector alone (P<2×10(-5)). Glycogen content was lower in skeletal muscles, including soleus (P<0.01), extensor digitorum longus (EDL; P<0.001), and tibialis anterior (P<0.05) following combination therapy, in comparison with vector alone. Glycogen remained elevated in the muscles following clenbuterol alone, indicating an adjunctive effect with gene therapy. Elderly GAA-KO mice treated with combination therapy demonstrated 2-fold increased wirehang latency, in comparison with vector or clenbuterol alone (P<0.001). The glycogen content of skeletal muscle decreased following combination therapy in elderly mice (P<0.05). Finally, CI-MPR-KO/GAA-KO mice did not respond to combination therapy, indicating that clenbuterol's effect depended on CI-MPR expression. In summary, adjunctive ß2-agonist treatment increased CI-MPR expression and enhanced efficacy from gene therapy in Pompe disease, which has implications for other lysosomal storage disorders that involve primarily the brain.

Stbd1 is highly elevated in skeletal muscle of Pompe disease mice but suppression of its expression does not affect lysosomal glycogen accumulation.

Previous studies strongly suggest that starch binding domain containing protein 1 (Stbd1) plays an important role in intracellular glycogen trafficking into lysosomes. We report here that Stbd1 expression is markedly increased in skeletal muscles but not in heart and liver of GAA-KO mice. An AAV2/9 vector expressing a Stbd1-specific shRNA effectively suppressed Stbd1 expression but did not alter lysosomal glycogen accumulation in the affected tissues of GAA-KO mice. Our results indicate that inhibition of Stbd1 does not appear to be an effective therapeutic approach for Pompe disease.

Alglucosidase alfa enzyme replacement therapy as a therapeutic approach for glycogen storage disease type III.

We investigated the feasibility of using recombinant human acid-α glucosidase (rhGAA, Alglucosidase alfa), an FDA approved therapy for Pompe disease, as a treatment approach for glycogen storage disease type III (GSD III). An in vitro disease model was established by isolating primary myoblasts from skeletal muscle biopsies of patients with GSD IIIa. We demonstrated that rhGAA significantly reduced glycogen levels in the two GSD IIIa patients' muscle cells (by 17% and 48%, respectively) suggesting that rhGAA could be a novel therapy for GSD III. This conclusion needs to be confirmed in other in vivo models.

Pathogenesis of growth failure and partial reversal with gene therapy in murine and canine Glycogen Storage Disease type Ia.

Glycogen Storage Disease type Ia (GSD-Ia) in humans frequently causes delayed bone maturation, decrease in final adult height, and decreased growth velocity. This study evaluates the pathogenesis of growth failure and the effect of gene therapy on growth in GSD-Ia affected dogs and mice. Here we found that homozygous G6pase (-/-) mice with GSD-Ia have normal growth hormone (GH) levels in response to hypoglycemia, decreased insulin-like growth factor (IGF) 1 levels, and attenuated weight gain following administration of GH. Expression of hepatic GH receptor and IGF 1 mRNAs and hepatic STAT5 (phospho Y694) protein levels are reduced prior to and after GH administration, indicating GH resistance. However, restoration of G6Pase expression in the liver by treatment with adeno-associated virus 8 pseudotyped vector expressing G6Pase (AAV2/8-G6Pase) corrected body weight, but failed to normalize plasma IGF 1 in G6pase (-/-) mice. Untreated G6pase (-/-) mice also demonstrated severe delay of growth plate ossification at 12 days of age; those treated with AAV2/8-G6Pase at 14 days of age demonstrated skeletal dysplasia and limb shortening when analyzed radiographically at 6 months of age, in spite of apparent metabolic correction. Moreover, gene therapy with AAV2/9-G6Pase only partially corrected growth in GSD-Ia affected dogs as detected by weight and bone measurements and serum IGF 1 concentrations were persistently low in treated dogs. We also found that heterozygous GSD-Ia carrier dogs had decreased serum IGF 1, adult body weights and bone dimensions compared to wild-type littermates. In sum, these findings suggest that growth failure in GSD-Ia results, at least in part, from hepatic GH resistance. In addition, gene therapy improved growth in addition to promoting long-term survival in dogs and mice with GSD-Ia.

Evaluation of carbon neutrality capacity based on a novel comprehensive model.

The Chinese government actively participates in global climate governance and has proposed to achieve the goal of carbon neutrality by 2060. Due to large differences in regional development, local governments need to comprehend their own carbon neutrality status and then scientifically plan a path to achieve carbon neutrality. In this study, we constructed a new carbon neutrality capacity evaluation indicator system named CNCIS, which can dynamically reflect the balance of energy, economy and environment in the process of reducing carbon emissions. In addition, to scientifically evaluate the carbon neutrality capacity, we proposed a novel comprehensive evaluation model, namely, the BWM-Entropy TOPSIS method, which can solve the unbalanced weighting and low efficiency problem in weighting indicators and improve the applicability of TOPSIS. Finally, based on real data from 30 provinces in China, we proved the effectiveness of our method and analyse the reasons for the different carbon neutrality capacities of the provinces. The main findings are as follows: (1) Clean and efficient utilization of energy had the greatest impact on achieving carbon neutrality, which is mainly represented by carbon emissions intensity, CO2 emissions per capita and coal consumption per capita. (2) In the energy, economy and environmental aspects, the factors that most affect carbon neutrality were carbon emissions intensity, the volume of technology marketing and water consumption per capita respectively. (3) Sorted by carbon neutrality capacities, the provinces could be divided into three categories, in which economically developed provinces more easily achieve carbon neutrality while resource-based provinces are the hardest. Based on these results, corresponding suggestions were proposed to help local governments scientifically plan a path to achieve carbon neutrality.

One-Dimensional Nickel Molybdate Nanostructures with Enhanced Supercapacitor Performance.

One-dimensional NiMoO4 nanofibers were successfully prepared by electrospinning and high-temperature calcination. The supercapacitor performance tests were conducted on the prepared materials in a three-electrode system, and it was found that the calcination temperature during the preparation of the fibers seriously affects the final morphology and electrochemical performance of the obtained samples. The sample with a calcination temperature of 500 °C has better performance, its specific capacitance can reach 1947 F g-1, and the retention rate is 82.35% after 3000 cycles of constant current charging-discharging. The improvement of electrochemical performance is primarily on account of the unique one-dimensional nanostructure of the material, which can both enhance the charge transfer efficiency and effectively increase the speed of electrolyte ion diffusion.

Scurvy in a young man: a rare case report.

Scurvy, resulting from vitamin C deficiency, has nonspecific constitutional symptoms, including weakness, malaise, and fatigue. It is frequently misdiagnosed due to the lack of specific clinical manifestations. Although there are sporadic cases of scurvy currently reported in children, scurvy in young people is seldom encountered. Here, we report on a 25-year-old male patient without any underlying conditions who presented with severe pain and ecchymoses of both lower extremities. He was diagnosed with scurvy due to a long history of staying indoors and inadequate intake of fruits or vegetables.

Clinical significance of anti-rheumatoid arthritis 33 antibody in patients with systemic lupus erythematosus.

Although anti-rheumatoid arthritis (RA) 33 antibodies have been reported to be present in various connective tissue diseases (CTDs), the clinical significance of anti-RA33 in CTDs is still obscure. This study was performed to explore the clinical significance of anti-RA33 in CTDs, especially systemic lupus erythematosus (SLE). A total of 565 patients with positive anti-nuclear antibodies who had been tested for anti-RA33 were included in this study and were further classified into RA33-positive and RA33-negative groups. The association between anti-RA33 and the clinical features of CTDs was examined. Receiver operating characteristic (ROC) analysis was performed to explore the diagnostic value of anti-RA33 in SLE and SLE-related organ involvement. The results showed that SLE was the most common disease in CTD patients positive for anti-RA33 (48.8%). Compared with the RA33-negative group, higher proportions of SLE-associated antibodies and SLE patients with a high disease activity as well as lower levels of serum complement components were observed in the RA33-positive group (all p < 0.05). Furthermore, CTD patients with positive anti-RA33 were more likely to suffer from mucocutaneous and hematological involvement as well as interstitial lung disease (all p < 0.05). ROC analysis revealed an area under the curve value of 0.634 (95% confidence interval: 0.587-0.681) for anti-RA33 in the diagnosis of SLE, with a specificity and sensitivity of 92.9% and 13.5%, respectively. Taken together, this study reveals a significant association between anti-RA33 and the clinical features of CTDs, especially SLE, indicating a potential clinical significance of anti-RA33 in the management of SLE.

Comparative proteome analysis of peripheral blood mononuclear cells in systemic lupus erythematosus with iTRAQ quantitative proteomics.

To identify and quantify protein profiles from peripheral blood mononuclear cells (PBMC) of systemic lupus erythematosus (SLE) patients with isobaric Tagging for Relative and Absolute protein Quantification (iTRAQ)-based proteomic technology and to find differentially expressed proteins in SLE. PBMC were collected from patients of six stable SLE, six active SLE, six rheumatoid arthritis (RA), and six healthy donors. After protein extraction and concentration, the pooled protein content was labeled with iTRAQ reagents and then subjected to multiple chromatographic fractionation and tandem mass spectrometry. ProteinPilot™ 3.0 software and a database of IPI (International Protein Index) human 3.62 were used for database searching and statistical analysis. A total of 452 proteins were identified. Of these, 67 unique proteins were observed twofold or more alteration in levels across groups. The proteins determined support existing knowledge and uncover novel biomarker candidates. These results indicate that iTRAQ-based technology can serve as a useful aid for identification and quantification proteins from PBMC.

Suppression of pullulanase-induced cytotoxic T cell response with a dual promoter in GSD IIIa mice.

Glycogen debranching enzyme deficiency in glycogen storage disease type III (GSD III) results in excessive glycogen accumulation in multiple tissues, primarily the liver, heart, and skeletal muscle. We recently reported that an adeno-associated virus vector expressing a bacterial debranching enzyme (pullulanase) driven by the ubiquitous CMV enhancer/chicken ß-actin (CB) promoter cleared glycogen in major affected tissues of infant GSD IIIa mice. In this study, we developed a potentially novel dual promoter consisting of a liver-specific promoter (LSP) and the CB promoter for gene therapy in adult GSD IIIa mice. Ten-week treatment with an adeno-associated virus vector containing the LSP-CB dual promoter in adult GSD IIIa mice significantly increased pullulanase expression and reduced glycogen contents in the liver, heart, and skeletal muscle, accompanied by the reversal of liver fibrosis, improved muscle function, and a significant decrease in plasma biomarkers alanine aminotransferase, aspartate aminotransferase, and creatine kinase. Compared with the CB promoter, the dual promoter effectively decreased pullulanase-induced cytotoxic T lymphocyte responses and enabled persistent therapeutic gene expression in adult GSD IIIa mice. Future studies are needed to determine the long-term durability of dual promoter-mediated expression of pullulanase in adult GSD IIIa mice and in large animal models.