Epigallocatechin Gallate, a Potential Immunomodulatory Agent of Tea Components, Diminishes Cigarette Smoke Condensate-Induced Suppression of Anti-Legionella pneumophila Activity and Cytokine Responses of Alveolar Macrophages

Even though cigarette smoking has been shown to suppress immune responses in the lungs, little is known about the effect of cigarette smoke components on respiratory infections. In the present study, the effects of cigarette smoke condensate (CSC) on bacterial replication in alveolar macrophages and the immune responses of macrophages to infection were examined. Furthermore, a possible immunotherapeutic effect of epigallocatechin gallate (EGCg), a major form of tea catechins, on the CSC-induced suppression of antimicrobial activity and immune responses of alveolar macrophages was also determined. The treatment of murine alveolar macrophage cell line (MH-S) cells with CSC significantly enhanced the replication of Legionella pneumophila in macrophages and selectively down-regulated the production of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) induced by bacterial infection. The treatment of macrophages with EGCg not only overcame the CSC-induced suppression of antimicrobial activity but also strengthened the resistance of macrophages to infection. EGCg also markedly up-regulated the CSC-suppressed IL-6 and TNF-α production by macrophages in response to infection. The results of exogenous TNF-α treatment and neutralization treatment with anti-TNF-α and anti-gamma-interferon (IFN-γ) antibodies and the determination of IFN-γ mRNA levels indicate that CSC-suppressed macrophages can be activated by EGCg to inhibit L. pneumophila growth by up-regulation of TNF-α and IFN-γ production. Thus, this study revealed that CSC selectively alters the immune responses of macrophages to L. pneumophila infection and leads to an enhancement of bacterial replication in macrophages. In addition, the tea catechin EGCg can diminish such suppressive effects of CSC on alveolar macrophages.     

Differential expression of PD-L1 and PD-L2, ligands for an inhibitory receptor PD-1, in the cells of lymphohematopoietic tissues

PD-1 is a member of the immunoglobulin superfamily expressed on immune cells, including T and B cells, and is involved in the delivery of inhibitory signal upon engagement of its ligands, PD-L1 and PD-L2. While the expression profile of PD-1 has been well documented, the analysis of PD-L1 and PD-L2 distributions on a protein basis has not been carried out because of the lack of available monoclonal antibodies specific for the molecules. In this study, we established two monoclonal antibodies, 1-111A and 122, specific for murine PD-L1 and PD-L2, respectively, and examined their expression profiles. Based on flow cytometric analyses, the expression of PD-L1 was detected in a variety of lymphohematopoietic cell types, including a minor proportion of T and B cells in the spleen, majority of pre-B cells and myeloid cells in bone marrow and subsets of thymocytes, while the expression of PD-L2 was not observed in the lymphohematopoietic cells at all. Notably, a significant proportion of the most immature lineage-marker-negative and c-Kit-positive bone marrow cells containing stem cells did express PD-L1. Following mitogenic stimulation, essentially all lymphocytes expressed PD-L1. Furthermore, a variety of leukemic lines also expressed PD-L1, while none of them did PD-L2. Thus, present results demonstrate the distinct expression patterns of PD-L1 and PD-L2 with the cells of lymphohematopoietic tissues exclusively expressing the former.     

Bax-inhibiting peptide protects glutamate-induced cerebellar granule cell death by blocking Bax translocation

Glutamate-induced excitotoxicity has been implicated in the pathogenesis of various neurological damages and disorders. In the brain damage of immature animals such as neonatal hypoxic-ischemic brain injury, the excitotoxicity appears to be more intimately involved through apoptosis. Bax, a member of the Bcl-2 family proteins, plays a key role in the promotion of apoptosis by translocation from the cytosol to the mitochondria and the release of apoptogenic factors such as cytochrome c. Recently, Bax-inhibiting peptide (BIP), a novel membrane-permeable peptide which can bind Bax in the cytosol and inhibit its translocation to the mitochondria, was developed. To investigate the possibility of a new neuroprotection strategy targeting Bax translocation in glutamate-induced neuronal cell death, cerebellar granule neurons (CGNs) were exposed to glutamate with or without BIP. Pretreatment of CGNs with BIP elicited a dose-dependent reduction of glutamate-induced neuronal cell death as measured by MTT assay. BIP significantly suppressed both the number of TUNEL-positive cells and the increase in caspases 3 and 9 activities induced by glutamate. In addition, immunoblotting after subcellular fractionation revealed that BIP prevented the glutamate-induced Bax translocation to the mitochondria and the release of cytochrome c from the mitochondria. These results suggest that agents capable of inhibiting Bax activity such as BIP might lead to new drugs for glutamate-related diseases in the future.     

A subcutaneously injected UV-inactivated SARS coronavirus vaccine elicits systemic humoral immunity in mice

The recent emergence of severe acute respiratory syndrome (SARS) was caused by a novel coronavirus, SARS-CoV. It spread rapidly to many countries and developing a SARS vaccine is now urgently required. In order to study the immunogenicity of UV-inactivated purified SARS-CoV virion as a vaccine candidate, we subcutaneously immunized mice with UV-inactivated SARS-CoV with or without an adjuvant. We chose aluminum hydroxide gel (alum) as an adjuvant, because of its long safety history for human use. We observed that the UV-inactivated SARS-CoV virion elicited a high level of humoral immunity, resulting in the generation of long-term antibody secreting and memory B cells. With the addition of alum to the vaccine formula, serum IgG production was augmented and reached a level similar to that found in hyper-immunized mice, though it was still insufficient to elicit serum IgA antibodies. Notably, the SARS-CoV virion itself was able to induce long-term antibody production even without an adjuvant. Anti-SARS-CoV antibodies elicited in mice recognized both the spike and nucleocapsid proteins of the virus and were able to neutralize the virus. Furthermore, the UV-inactivated virion induced regional lymph node T-cell proliferation and significant levels of cytokine production (IL-2, IL-4, IL-5, IFN-gamma and TNF-alpha) upon restimulation with inactivated SARS-CoV virion in vitro. Thus, a whole killed virion could serve as a candidate antigen for a SARS vaccine to elicit both humoral and cellular immunity.     

Comparison of HER2 immunohistochemical results using a monoclonal antibody (SV2-61γ) and a polyclonal antibody (for Dako HercepTest) in advanced gastric cancer

We compared a monoclonal antibody (SV2-61γ) and a polyclonal antibody (Dako HercepTest) in immunohistochemical assessments of human epidermal growth factor receptor 2 (HER2) expression in 73 samples of advanced gastric cancer. Results were scored as 0 to 3+, and equivocal or discordant (SV2-61γ/Dako HercepTest = 0/2+, 0/3+, 1+/3+ or 2+/3+) cases were subjected to fluorescence in situ hybridization (FISH) analysis. The frequencies of HER2 scores of 2+ or 3+ were 15.1% (11/73) using SV2-61γ and 38.4% (28/73) using Dako HercepTest. All of the equivocal or discordant cases with a HER2 score of 3+ using Dako HercepTest exhibited amplification of the HER2 gene regardless of the HER2 score determined with SV2-61γ. The results of the HER2 tests differed according to the antibodies used for immunohistochemistry that preceded FISH analysis, being 15.1% (11/73) using SV2-61γ and 23.3% (17/73) using Dako HercepTest. Thus, therapeutic decisions might be markedly influenced by the selection of antibody used in the HER2 test.     

Effects of chromium and nitrogen content on the microstructures and mechanical properties of as-cast Co-Cr-Mo alloys for dental applications

The microstructure and mechanical properties of as-cast Co-(20-33)Cr-5Mo-N alloys were investigated to develop ductile Co-Cr-Mo alloys without Ni addition for dental applications that satisfy the requirements of the type 5 criteria in ISO 22674. The effects of the Cr and N contents on the microstructure and mechanical properties are discussed. The microstructures were evaluated using scanning electron microscopy with energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), and electron back-scattered diffraction pattern analysis. The mechanical properties were evaluated using tensile testing. The proof strength and elongation of N-containing 33Cr satisfied the type 5 criteria in ISO 22674. ε-phase with striations was formed in the N-free (20-29)Cr alloys, while there was slight formation of ε-phase in the N-containing (20-29)Cr alloys, which disappeared in N-containing 33Cr. The lattice parameter of the γ-phase increased with increasing Cr content (i.e. N content) in the N-containing alloys, although the lattice parameter remained almost the same in the N-free alloys because of the small atomic radius difference between Co and Cr. Compositional analyses by EDS and XRD revealed that in the N-containing alloys Cr and Mo were concentrated in the cell boundary, which became enriched in N, stabilizing the γ-phase. The mechanical properties of the N-free alloys were independent of the Cr content and showed low strength and limited elongation. Strain-induced martensite was formed in all the N-free alloys after tensile testing. On the other hand, the proof strength, ultimate tensile strength, and elongation of the N-containing alloys increased with increasing Cr content (i.e. N content). Since formation of ε-phase after tensile testing was confirmed in the N-containing alloys the deformation mechanism may change from strain-induced martensite transformation to another form, such as twinning or dislocation slip, as the N content increases. Thus the N-containing 33Cr alloy with large elongation is promising for use in dentures with adjustable clasps through one piece casting.     

Canine Oral Mucosal Fibroblasts Differentiate into Osteoblastic Cells in Response to BMP‐2

Several lines of evidence show that transplantation of osteoblastic cells or genetically engineered nonosteogenic cells expressing osteoblast‐related genes into bone defects effectively promotes bone regeneration. To extend this possibility, we investigated whether oral mucosal fibroblasts are capable of differentiating into osteoblastic cells by conducting in vitro and in vivo experiments. We investigated the effects of bone morphogenetic protein‐2 (BMP‐2) on osteoblast differentiation of cultured fibroblasts isolated from canine buccal mucosa. We also transplanted green fluorescence protein (GFP)‐expressing fibroblasts with gelatin/BMP‐2 complexes into the subfascial regions of athymic mice, and investigated the localization of GFP‐positive cells in the ectopically formed bones. The cultured canine buccal mucosal fibroblasts differentiated into osteoblastic cells by increasing their alkaline phosphatase (ALP) activity and Osteocalcin, Runx2, and Osterix mRNA expression levels in response to BMP‐2. Transplantation experiments of GFP‐expressing oral mucosal fibroblasts with gelatin/BMP‐2 complexes revealed that 17.1% of the GFP‐positive fibroblasts differentiated into ALP‐positive cells, and these cells accounted for 6.2% of total ALP‐positive cells in the ectopically formed bone. This study suggests that oral mucosal fibroblasts can differentiate into osteogenic cells in response to BMP‐2. Thus, these cells are potential candidates for cell‐mediated bone regeneration therapy in dentistry. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

Infusion of a Glucose Solution Reduces Autophagy in the Liver after LPS-induced Systemic Inflammation

Autophagy is a natural process by which a cell maintains homeostasis, usually taking place unnoticed by adjacent cells. Glucose is involved in a negative feedback loop in autophagy. Autophagy is characterized by the induction and secretion of HMGB1, yet the nature of the inflammatory response during and the effect of glucose administration on autophagy are not well understood. Systemic inflammation was induced in experimental animals by LPS injection (7.5 mg/kg) followed by a continuous infusion of either 1%, 5%, or 25% glucose. Autophagy was visualized by immunohistochemistry 12 h after LPS injection. Likewise, protein levels of microtubule-associated protein light chain 3 (LC3)-II, autophagy-related protein 7 (Atg7), and high-mobility group box 1 (HMGB1) were assayed by western blot analysis. We found that autophagy increased in liver tissue in response to LPS-induced systemic inflammation. However, protein levels decreased in rats receiving LPS and a 5% glucose solution. Our results suggest that LPS-induced systemic inflammation increases autophagy in liver cells, potentially involving the upregulation of LC3-II, Atg7, and HMGB1. We also show that a 5% glucose infusion reduces autophagy. We propose that maintaining serum glucose levels with an adequate glucose dose improves systemic inflammation by reducing autophagy.     

Gonadotropin levels at the start of ovarian stimulation predict normal fertilization after hCG re-trigger in GnRH antagonist cycles

PurposeTo assess the appropriateness of human chorionic gonadotropin (hCG) re‐trigger in poor responders to gonadotropin‐releasing hormone agonist (GnRHa) trigger in controlled ovarian stimulation (COS) cycles.MethodsThe 2251 cycles in 2251 patients triggered with GnRHa for oocyte stimulation, with or without requiring hCG re‐trigger between 2013 and 2018, were retrospectively analyzed to compare gonadotropin levels at the start of COS and the rate of normal fertilization between the re‐trigger and non–re‐trigger group. Furthermore, patients in the re‐trigger group were stratified by the rate of normal fertilization (good: ≥60% or poor: <60%) to compare patient demographics, hormone profiles, and clinical outcome between the subgroups.ResultsIn the re‐trigger group, FSH and LH levels at the start of COS were significantly lower in the good fertilization group than in the poor fertilization group (P < .01). Receiver operating characteristic curves identified cutoff values of the FSH and LH levels of 1.30 and 0.35 mIU/mL, respectively, for predicting ≥60% normal fertilization.ConclusionGonadotropin levels at the start of COS are predictors of response to GnRHa trigger and hCG re‐trigger necessity, and may serve as indicators to help clinicians appropriately choose hCG re‐trigger rather than abandoning the cycles or continuing the first oocyte aspiration attempt.