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B cells play a major role in the adaptive immune response by producing antigen-specific antibodies against pathogens and imparting immunological memory. Following infection or vaccination, antibody-secreting B cells and memory B cells are generated in specialized regions of lymph nodes and spleens, called germinal centers. Here, we report a fully synthetic ex-vivo system that recapitulates the generation of antigen-specific germinal-center (GC) like B cells using material-surface driven polyvalent signaling. This synthetic germinal center (sGC) reaction was effectively induced using biomaterial-based artificial "follicular T helper cells (T FH )" that provided both natural CD40-CD40L ligation as well as crosslinking of CD40 and by mimicking artificial "follicular dendritic cells (FDC)" to provide efficient, polyvalent antigen presentation. The artificial sGC reaction resulted in efficient B cell expansion, immunoglobulin (Ig) class switching, and expression of germinal center phenotypes. Antigen presentation during sGC reaction selectively enhanced the antigen-specific B cell population and induced somatic hyper-mutations for potential affinity maturation. The resulting B cell population consisted primarily of GC-like B cells (centrocytes) as well as some plasma-like B cells expressing CD138. With concurrent cell sorting, we successfully created highly enriched populations of antigen-specific B cells. Adoptive transfer of these GC-like B cells into non-irradiated isogeneic or non-lethally irradiated congenic recipient mice showed successful engraftment and survival of the donor cells for the 4 week test period. We show that this material-surface driven sGC reaction can be successfully applied to not only splenic B cells but also B cells isolated from more therapeutically relevant sources such as peripheral blood mononuclear cells (PBMCs), thus making our current work an exciting prospect in the new era of personalized medicine and custom-immunotherapy., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Reactive oxygen species (ROS) have many physiological and pathological effects on diverse cellular events. In particular, excessive ROS causes oxidative stress that leads to cell death. The mammalian STE20-like kinase-1 (MST1), a multifunctional serine-threonine kinase, plays a pivotal role in oxidative stress-induced cellular signaling events. Tumor necrosis factor receptor (TNFR)-associated factor 2 (TRAF2) is also known to be essential for oxidative stress-induced cell death. Here, we showed that H2O2 induced the physical interaction between TRAF2 and MST1, and that this interaction promoted the homodimerization as well as the activation of MST1. Furthermore, TRAF2 was required for MST1 to mediate the H2O2-induced stimulation of c-Jun N-terminal kinase and p38 kinase as well as apoptosis. Taken together, our results suggest that TRAF2 functions as a key activator of MST1 in oxidative stress-induced intracellular signaling processes., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease. Gallium nitrate has been reported to reserve immunosuppressive activities. Therefore, we assessed the therapeutic effects of gallium nitrate in the mouse model of developed type II collagen-induced arthritis (CIA). CIA was induced by bovine type II collagen with Complete Freund's adjuvant. CIA mice were intraperitoneally treated from day 36 to day 49 after immunization with 3.5mg/kg/day, 7mg/kg/day gallium nitrate or vehicle. Gallium nitrate ameliorated the progression of mice with CIA. The clinical symptoms of collagen-induced arthritis did not progress after treatment with gallium nitrate. Gallium nitrate inhibited the increase of CD4(+) T cell populations (p<0.05) and also inhibited the type II collagen-specific IgG2a-isotype autoantibodies (p<0.05). Gallium nitrate reduced the serum levels of TNF-α, IL-6 and IFN-γ (p<0.05) and the mRNA expression levels of these cytokine and MMPs (MMP2 and MMP9) in joint tissues. Western blotting of members of the NF-κB signaling pathway revealed that gallium nitrate inhibits the activation of NF-κB by blocking IκB degradation. These data suggest that gallium nitrate is a potential therapeutic agent for autoimmune inflammatory arthritis through its inhibition of the NF-κB pathway, and these results may help to elucidate gallium nitrate-mediated mechanisms of immunosuppression in patients with RA., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Human papillomavirus (HPV) testing is an important part of cervical cancer screening and management of women with abnormal cytology results. The Hybrid Capture 2 (HC2) has been recommended for use as a reference test., Objective: To evaluate a new real-time PCR assay (Anyplex II HPV28) for detecting high risk (HR) HPV and to compare it to the HC2. In addition, we compared the genotyping results of the Anyplex II HPV28 to those of sequencing analysis., Study Design: A total of 1114 cervical swab specimens were consecutively obtained from a single healthcare center. We submitted all specimens for HPV detection with Anyplex II HPV28 and HC2, then analyzed the discordant results using multiplex PCR followed by direct sequencing., Results: HC2 detected 72 (6.5%) cases with HR HPV, while Anyplex II HPV28 identified 138 (12.4%) cases. The overall agreement rate was 91.4% (1018/1114) of cases. Discordant results between these two assays were observed in 96 cases; 15 were positive only by HC2, and 81 were positive only by Anyplex II HPV28. Sequencing analyses performed in 80 cases of discordant results revealed 11 false-positive, and 67 false-negative results using HC2 tests and two false-positive results using Anyplex II HPV28., Conclusions: The Anyplex II HPV28 assay is analytically more sensitive in the detection of the 13 HR types represented by the HC2 assay and exhibited a higher concordance with comprehensive genotyping based on the sequencing analysis, and it could be used as a laboratory testing method for identifying HPV genotypes., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In hypoxic/ischemic conditions, neuronal apoptotic events are occurred, resulting in neuronal diseases. Estradiol is a female sex hormone with steroid structure known to provide neuroprotection through multiple mechanisms in the central nervous system. This study was aimed to investigate the signal transduction pathway leading to the inhibitory effects of estradiol against cobalt chloride (CoCl(2))-mediated hypoxic death in PC12 cells. Estradiol inhibits CoCl(2)-induced cell death with genomic DNA fragmentation and morphologic changes such as cell shrinkage and condensed nuclei. Pre-incubation of estradiol prior to CoCl(2) treatment attenuated CoCl(2)-mediated the reactive oxygen species (ROS) production and limited the activities of the caspase cascades, such as caspase-8, -9 and -3. Furthermore, estradiol downregulated the Bax:Bcl-2 ratio and decreased the release of cytochrome c from the mitochondria into the cytosol in CoCl(2)-treated cells, indicating that estradiol affect on mitochondrial pathway. Estradiol attenuated also CoCl(2)-induced upregulation of Fas-ligand (Fas-L) and truncated of Bid in sequence of death receptor-mediated pathway. In addition, estradiol increased the phosphorylation of Akt in CoCl(2)-treated cells, demonstrating that estradiol has no affect on upstream signaling through the PI3K/Akt in inhibition of CoCl(2)-induced apoptosis in PC12 cells. Taken together, estradiol was found to have a neuroprotective effect against CoCl(2)-induced apoptosis of PC12 cells by the attenuating ROS production and the modulating apoptotic signal pathway through Bcl-2 family, cytochrome c, Fas/Fas-L as well as PI3K/Akt pathway.

Advances in nanotechnology, in particular the development of novel types of nanoparticles, will result in advanced tools for biomedical research and clinical practice. One exciting aspect of future nanomaterial research will be the possibility to combine therapy and imaging in multifunctional nanoparticle designs. In this context, anisotropic particles with subcellular dimensions may offer so far unattainable capabilities, because they could provide access to directional information with respect to nanoparticle-cell interactions. We have recently developed an electrified jetting process, which can produce water-stable polymer particles with two distinct phases. To address the first critical hurdle towards the application of these biphasic nanocolloids as imaging probes, short-term biocompatibility was evaluated using model cell culture systems. Exposure of human endothelial cells and murine fibroblasts to biphasic nanocolloids made of 0.5% polyacrylic acid and 4.5% poly(acrylamide-co-acrylic acid) did not affect cell proliferation as determined by a colorimetric proliferation assay. Moreover, double staining with Annexin V and propidium iodide and subsequent flow cytometric analysis indicated high cell viability, although slightly decreased viability was observed at the highest dose tested (1mg particles/10(6) seeded cells). Particle internalization as well as surface binding occurred simultaneously for both cell types, as evidenced by confocal laser scanning microscopy. Taken together, these results suggest excellent short-term biocompatibility in physiological systems for wide concentration ranges of the biphasic nanocolloids and open possibilities for future work investigating receptor- or surface marker-mediated targeting.

Reactive oxygen species (ROS), generated by infiltrating neutrophils, are considered as an important regulator in the pathogenesis and development of pancreatitis. A hallmark of the inflammatory response is the induction of cytokine gene expression, which may be regulated by oxidant-sensitive transcription factor, nuclear factor-kappaB (NF-kappaB). Present study aims to investigate whether neutrophils primed by 4beta-phorbol 12beta-myristate 13alpha-acetate (PMA) affect the productions of H(2)O(2) and lipid peroxide (LPO), NF-kappaB activation and cytokine production in pancreatic acinar cells, and whether these alterations were inhibited by N-acetylcysteine (NAC) and superoxide dismutase (SOD). Neutrophils generated ROS by stimulation with PMA, which was inhibited by NAC and SOD. In acinar cells, PMA-primed neutrophils increased the productions of H(2)O(2), LPO, and cytokines both time and dose dependently. PMA-primed neutrophils resulted in the activation of two species of NF-kappaB dimers (a p50/p65 heterodimer and a p50 homodimer) in acinar cells. Both NAC and SOD inhibited neutrophil-induced, oxidant-mediated alterations in acinar cells. In conclusion, ROS, generated by neutrophils, activates NF-kappaB, resulting in upregulation of inflammatory cytokines in acinar cells. Antioxidants such as NAC might be useful antiinflammatory agents by inhibiting oxidant-mediated activation of NF-kappaB and decreasing cytokine production.