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A comprehensive structure–activity relationship study on antibody Fc-glycosylation has been performed using the chimeric anti-SSEA4 antibody chMC813-70 as a model.

The globo-series glycosphingolipids (SSEA3, SSEA4, and Globo H) were shown to express in many cancers selectively, and a combination of anti-SSEA4 and anti-Globo H antibodies was able to suppress tumor growth in mice inoculated with breast cancer cell lines. To further understand the effect, we focused on the combined effect of the two antibodies in target binding and antibody-dependent cellular cytotoxicity (ADCC) in vitro. Here, we report that the binding of anti-Globo H antibody (VK9) to MDA-MB231 breast cancer cells was influenced by anti-SSEA4 antibody (MC813-70), and a combination of both antibodies induced a similar effect as did anti-SSEA4 antibodies alone in a reporter-based ADCC assay, indicating that SSEA4 is a major target in breast cancer due to its higher expression than Globo H. Furthermore, we showed that a homogeneous anti-SSEA4 antibody (chMC813-70-SCT) designed to maximize the ADCC activity can be used to isolate a subpopulation of natural killer (NK) cells that exhibit an ∼23% increase in killing the target cells as compared to the unseparated NK cells. These findings can be used to predict a therapy outcome based on the expression levels of antigens and evaluate therapeutic antibody development.

The globo-series glycosphingolipids (GSLs) SSEA3, SSEA4, and Globo-H specifically expressed on cancer cells are found to correlate with tumor progression and metastasis, but the functional roles of these GSLs and the key enzyme β1,3-galactosyltransferase V (β3GalT5) that converts Gb4 to SSEA3 remain largely unclear. Here we show that the expression of β3GalT5 significantly correlates with tumor progression and poor survival in patients, and the globo-series GSLs in breast cancer cells form a complex in membrane lipid raft with caveolin-1 (CAV1) and focal adhesion kinase (FAK) which then interact with AKT and receptor-interacting protein kinase (RIP), respectively. Knockdown of β3GalT5 disrupts the complex and induces apoptosis through dissociation of RIP from the complex to interact with the Fas death domain (FADD) and trigger the Fas-dependent pathway. This finding provides a link between SSEA3/SSEA4/Globo-H and the FAK/CAV1/AKT/RIP complex in tumor progression and apoptosis and suggests a direction for the treatment of breast cancer, as demonstrated by the combined use of antibodies against Globo-H and SSEA4.

This study details the synthesis of high-activity g-C3N4 catalysts for H2 generation from a triethanolamine aqueous solution under visible light. We anneal a mixture of urea and NH4Cl to obtain g-C3N4 nanosheets, which are subsequently solvated with ethanol molecules and annealed to form aromatic carbon-doped g-C3N4. The results of analyses conducted using X-ray photoelectron, Fourier-transform infrared, and carbon-13 nuclear magnetic resonance spectroscopies demonstrated that annealing the ethanol molecules leads to the grafting of aromatic heterocycles on the g-C3N4 nanosheets and substitution of nitrogen with carbon. The grafted aromatic heterocycles and doped carbon atoms extend the π-conjugation system in g-C3N4 to reduce the band gap and facilitate the separation of photogenerated charges. The carbon-incorporating also preserve the crystallinity of g-C3N4 during high-temperature annealing, which facilitates the suppression of the recombination of photogenerated charges at defect sites. The developed...

Background Group A streptococcus (GAS) is a common pathogen in children. Macrolide resistance in GAS has been described worldwide. The aims of this study are to analyze macrolide resistance of GAS isolates in southern Taiwan and to clarify the relationship of emm typing and macrolide resistance in the past decade. Methods All GAS isolated from patients younger than 18 years at a single tertiary center in southern Taiwan were collected from 2000 to 2012. Antibiotics susceptibility to erythromycin, azithromycin, and clindamycin were determined by agar dilution method, and were interpreted by Clinical and Laboratory Standards Institute (CLSI) standards. emm typing was performed by polymerase chain reaction (PCR). Results A total of 301 isolates were collected during the period of 13 years. Scarlet fever (38.5%) and acute pharyngitis (32.2%) were the most common diagnosis. Decreased resistance rate of erythromycin from 53.1% in 2000 to 0% in 2010 was found, but it increased rapidly to 65% in 2011. The resistance rate of azithromycin was the lowest (4.2%) in 2005, but was higher than 15% after 2006. The involvement of the erythromycin resistance genes were mef A (53.1%), erm B (35.9%), and erm TR (10.9%). The resistance of clindamycin also increased since 2011. emm 12 was the most common serotype and accounted for 44.9% of all isolates. Compared with the non- emm 12 group, resistance to erythromycin, azithromycin, and clindamycin were more frequently detected in the emm 12 group. Conclusion Increased resistance of GAS to macrolide and clindamycin was found in recent years. emm 12 was the main serotype for macrolide resistance.

Energy efficiency is a critical issue for battery-driven mobile devices. The popularity of mobile games with increasingly sophisticated graphics raises an urgent need for an online power governor for both CPUs and GPUs. This study proposes an adaptive on-line CPU-GPU governor for games on mobile devices to minimize energy consumption. The concept is implemented on a Google Nexus 7 device and evaluated using real world gaming applications (APPs). The results show an energy savings of up to 26% compared to the Performance governor in Linux (include network, screen, and system idle power) while maintaining a stable user experience.

Hepatitis C virus (HCV) infection is a major cause of chronic hepatitis and hepatocellular carcinoma. It infects human liver cells through several cellular protein receptors including CD81, SR-BI, claudin-1, and occludin. Previous reports also show that lectin receptors can mediate HCV recognition and entry. The envelope proteins of HCV (E1 and E2) are heavily glycosylated, further indicating the possible roles of lectin receptor-virus interaction in HCV infection. However, there is limited study investigating the relationship of HCV envelope glycoproteins and lectin as well as non-lectin receptors. Here we used surface plasmon resonance to examine the binding affinity of different glycoforms of recombinant HCV envelope protein to receptors and inspected the infectivity and assembly of HCV pseudoparticles composed of different glycoforms of envelope proteins. Our results indicated that DC-SIGN, L-SIGN, and Langerin had higher affinity to recombinant HCV envelope proteins in the presence of calcium ions than non-lectin receptors, and envelope proteins with Man8/9 N-glycans showed approximate 10-fold better binding to lectin receptors than envelope proteins with Man5 and complex type N-glycans. Interestingly, comparing among glycoforms, recombinant envelope proteins with Man5 N-glycans showed the highest binding affinity when interacting with non-lectin receptors. In summary, the glycans on HCV envelope protein play a modulatory role in HCV assembly and infection and direct HCV-receptor interaction, which mediates viral entry in different cells. Receptors with high affinity to HCV envelope proteins may be considered as targets for development of a therapeutic strategy against HCV.

The larvae of the cestodes belonging to the genus Echinococcus dwell primarily in mammalian liver. They are protected by the laminated layer (LL), an acellular mucin-based structure. The glycans decorating these mucins constitute the overwhelming majority of molecules exposed by these larvae to their hosts. However, their decoding by host innate immunity has not been studied. Out of 36 mammalian innate receptors with carbohydrate-binding domains, expressed as Fc fusions, only the mouse Kupffer cell receptor (KCR; CLEC4F) bound significantly to the Echinococcus granulosus LL mucins. The receptor also bound the Echinococcus multilocularis LL. Out of several synthetic glycans representing Echinococcus LL structures, the KCR bound strongly in particular to those ending in Galα1-4Galβ1-3 or Galα1-4Galβ1-4GlcNAc, both characteristic LL carbohydrate motifs. LL carbohydrates may be optimized to interact with the KCR, expressed only in liver macrophages, cells known to contribute to the tolerogenic antigen presentation that is characteristic of this organ.

The discovery of cancer stem cells (CSCs), which are responsible for self-renewal and tumor growth in heterogeneous cancer tissues, has stimulated interests in developing new cancer therapies and early diagnosis. However, the markers currently used for isolation of CSCs are often not selective enough to enrich CSCs for the study of this special cell population. Here we show that the breast CSCs isolated with CD44(+)CD24(-/lo)SSEA-3(+) or ESA(hi)PROCR(hi)SSEA-3(+) markers had higher tumorigenicity than those with conventional markers in vitro and in vivo. As few as 10 cells with CD44(+)CD24(-/lo)SSEA-3(+) formed tumor in mice, compared with more than 100 cells with CD44(+)CD24(-/lo). Suppression of SSEA-3 expression by knockdown of the gene encoding β-1,3-galactosyltransferase 5 (β3GalT5) in the globo-series pathway, led to apoptosis in cancer cells specifically but had no effect on normal cells. This finding is further supported by the analysis of SSEA-3 and the two related globo-series epitopes SSEA4 and globo-H in stem cells (embryonic stem cells and induced pluripotent stem cells) and various normal and cancer cells, and by the antibody approach to target the globo-series glycans and the late-stage clinical trials of a breast cancer vaccine.

The surface modification method for a substrate affects its cyto-compatibility. Collagen coating has been considered as an effective way to vary the biological interactions occurring on the Ti6Al4V substrate. However, a uniform collagen coating is difficult to be prepared by direct collagen coating method. In this study, a simple and efficient method was developed to coat a homogenous collagen top layer on a Ti6Al4V sample that was precoated with a biomimetic Ca–P intermediate layer. Scanning electron microscopy (SEM) observations show that a non-uniform collagen coating formed on the surface of a pristine Ti6Al4V substrate, whereas a continuous and homogenous collagen coating formed on a Ti6Al4V surface pre-coated with Ca–P. Human osteosarcoma cells (HOS) were cultured and their cell morphology examined using SEM after 3 and 24 h. After seeding the cultured cell onto the substrates, cell proliferation was measured using the AlamarBlue assay at 1, 5, and 10 days. It was found that cells seeded onto collagen and Collagen/Ca–P coated substrates yielded well-developed filopodia and lamellipodia. However, the cell proliferation of Collagen/Ca–P was significantly higher than those of the other specimen for 5- and 10-day culture specimen. These results suggest that the proposed method can be used to deposit a uniform collagen coating on specimens for biomedical applications.

Glioblastoma multiforme (GBM), the grade IV astrocytoma, is the most common and aggressive brain tumor in adults. Despite advances in medical management, the survival rate of GBM patients remains poor, suggesting that identification of GBM-specific targets for therapeutic development is urgently needed. Analysis of several glycan antigens on GBM cell lines revealed that eight of 11 GBM cell lines are positive for stage-specific embryonic antigen-4 (SSEA-4), and immunohistochemical staining confirmed that 38/55 (69%) of human GBM specimens, but not normal brain tissue, were SSEA-4(+) and correlated with high-grade astrocytoma. In addition, an SSEA-4-specific mAb was found to induce complement-dependent cytotoxicity against SSEA-4(hi) GBM cell lines in vitro and suppressed GBM tumor growth in mice. Because SSEA-4 is expressed on GBM and many other types of cancers, but not on normal cells, it could be a target for development of therapeutic antibodies and vaccines.

Background/Purpose Childhood tuberculosis (TB) continues to be a major public health problem in Taiwan. Taiwan remains a highly endemic area despite neonatal Bacillus Calmette–Guerin (BCG) vaccination and the availability of anti-TB therapy. The presentation is highly variable and it is often difficult to make an accurate diagnosis. This study was designed to evaluate the demographic, clinical, and laboratory findings and outcomes of TB in children with emphasis on central nervous system (CNS) complications. Methods The medical records of 80 children diagnosed with TB at a medical center in southern Taiwan over the past 24 years (1988–2012) were reviewed. Results Among them, 48.8% (39/80) had pulmonary TB, 27.5% (22/80) had isolated extrapulmonary TB, and 23.7% (19/80) had disseminated TB. Most infected cases were aged either 12 years. TB contact history was found in 42.5% (34/80) cases. Fourteen (17.5%) of the cases had CNS involvement. The most common presentations were fever (85.7%), signs of increased intracranial pressure (71.4%), drowsiness (64.3%), and focal neurological signs (57.1%). The major radiological findings were tuberculoma (50%), basilar enhancement (41.6%), infarction (41.6%), hydrocephalus (16.6%), and transverse myelitis (16.6%). The case fatality of CNS TB was 14.3% and 21.4% had neurologic sequelae. Conclusion Findings suggest that positive exposure history and suspicious clinical presentations are important clues for further confirmatory laboratory and image studies in childhood TB. CNS TB usually presented as part of disseminated TB in children. Early diagnosis and treatment may lead to favorable outcomes in CNS TB.