Sterically Bulky Caging of Transferrin for Photoactivatable Intracellular Delivery.

Photoactivatable ligand proteins are potentially useful for light-induced intracellular delivery of therapeutic and diagnostic cargos through receptor-mediated cellular uptake. Here, we report the simple and effective caging of transferrin (Tf), a representative ligand protein with cellular uptake ability, which has been used in the delivery of various cargos. Tf was modified with several biotin molecules through a photocleavable linker, and then the biotinylated Tf (bTf) was conjugated with the biotin-binding protein, streptavidin (SA), to provide steric hindrance to block the interaction with the Tf receptor. Without exposure to light, the cellular uptake of the bTf-SA complex was effectively inhibited. In response to light exposure, the complex was degraded with the release of Tf, leading to cellular uptake of Tf. Similarly, the cellular uptake of Tf-doxorubicin (Dox) conjugates could be suppressed by caging with biotinylation and SA binding, and the intracellular delivery of Dox could be triggered in a light-dependent manner. The intracellularly accumulated Dox decreased the cell viability to 25% because of the cell growth inhibitory effect of Dox. These results provided proof of principle that the caged Tf can be employed as a photoactivatable molecular device for the intracellular delivery of cargos.

Separation and Analysis of Adherent and Non-Adherent Cancer Cells Using a Single-Cell Microarray Chip.

A new single-cell microarray chip was designed and developed to separate and analyze single adherent and non-adherent cancer cells. The single-cell microarray chip is made of polystyrene with over 60,000 microchambers of 10 different size patterns (31-40 µm upper diameter, 11-20 µm lower diameter). A drop of suspension of adherent carcinoma (NCI-H1650) and non-adherent leukocyte (CCRF-CEM) cells was placed onto the chip, and single-cell occupancy of NCI-H1650 and CCRF-CEM was determined to be 79% and 84%, respectively. This was achieved by controlling the chip design and surface treatment. Analysis of protein expression in single NCI-H1650 and CCRF-CEM cells was performed on the single-cell microarray chip by multi-antibody staining. Additionally, with this system, we retrieved positive single cells from the microchambers by a micromanipulator. Thus, this system demonstrates the potential for easy and accurate separation and analysis of various types of single cells.

Innate partnership of HLA-B and KIR3DL1 subtypes against HIV-1.

Allotypes of the natural killer (NK) cell receptor KIR3DL1 vary in both NK cell expression patterns and inhibitory capacity upon binding to their ligands, HLA-B Bw4 molecules, present on target cells. Using a sample size of over 1,500 human immunodeficiency virus (HIV)+ individuals, we show that various distinct allelic combinations of the KIR3DL1 and HLA-B loci significantly and strongly influence both AIDS progression and plasma HIV RNA abundance in a consistent manner. These genetic data correlate very well with previously defined functional differences that distinguish KIR3DL1 allotypes. The various epistatic effects observed here for common, distinct KIR3DL1 and HLA-B Bw4 combinations are unprecedented with regard to any pair of genetic loci in human disease, and indicate that NK cells may have a critical role in the natural history of HIV infection.

Analysis of binding of KIR3DS1*014 to HLA suggests distinct evolutionary history of KIR3DS1.

NK cell activity is regulated by the integration of positive and negative signals. One important source of these signals for human NK cells is the killer Ig-like receptor (KIR) family, which includes both members that transduce positive and those that generate negative signals. KIR3DL1 inhibits NK cell activity upon engagement by its ligand HLA-Bw4. The highly homologous KIR3DS1 is an activating receptor, which is implicated in the outcome of a variety of pathological situations. However, unlike KIR3DL1, direct binding of KIR3DS1(+) cells to HLA has not been demonstrated. We analyzed four key amino acid differences between KIR3DL1*01502 and KIR3DS1*013 to determine their role in KIR binding to HLA. Single substitutions of these residues dramatically reduced binding by KIR3DL1. In the reciprocal experiment, we found that the rare KIR3DS1 allotype KIR3DS1*014 binds HLA-Bw4 even though it differs from KIR3DS1*013 at only one of these positions (position 138). This reactivity was unexpectedly dependent on residues at other variable positions, as HLA-Bw4 binding was lost in receptors with KIR3DL1-like residues at both positions 199 and 138. These data provide the first evidence, to our knowledge, for the direct binding of KIR3DS1(+) cells to HLA-Bw4 and highlight the key role for position 138 in determining ligand specificity of KIR3DS1. They also reveal that KIR3DS1 reactivity and specificity is dictated by complex interactions between the residues in this region, suggesting a unique functional evolution of KIR3DS1 within the activating KIR family.

Systematic literature review of the disease burden and vaccination of pneumococcal disease among adults in select Asia-Pacific areas.

INTRODUCTION: Pneumococcal diseases are common and cause significant morbidity and mortality, with higher rates especially in developing areas including many in the Asia-Pacific (AP) region. However, current strategies to prevent pneumococcal disease in adults are quite complicated and not well implemented among many AP areas, and vaccination coverage rates among adults are generally low or perceived as low in the region. Thus, this literature review's purpose was to summarize the disease burden and vaccination against pneumococcal diseases among adults in select AP areas (Australia, Hong Kong, India, Indonesia, South Korea, Malaysia, New Zealand, the Philippines, Singapore, Taiwan, Thailand, and Vietnam). AREAS COVERED: This systematic review included published articles from January 2010 to August 2020 using MEDLINE/Embase. Grey literature websites were searched for national immunization programs and medical society vaccination recommendations from areas of interest. A total of 69 publications were identified. EXPERT OPINION: In the AP region, pneumococcal disease burden and serotype prevalence are variable among adult populations, particularly among older adults. Data was provided primarily from countries with established national immunization programs (NIPs). Further research on the disease burden and emphasis on the benefits of vaccination in AP areas lacking pneumococcal vaccination programs is warranted.

Analysis of Single Nucleotide-Mutated Single-Cancer Cells Using the Combined Technologies of Single-Cell Microarray Chips and Peptide Nucleic Acid-DNA Probes.

Research into cancer cells that harbor gene mutations relating to anticancer drug-resistance at the single-cell level has focused on the diagnosis of, or treatment for, cancer. Several methods have been reported for detecting gene-mutated cells within a large number of non-mutated cells; however, target single nucleotide-mutated cells within a large number of cell samples, such as cancer tissue, are still difficult to analyze. In this study, a new system is developed to detect and isolate single-cancer cells expressing the T790M-mutated epidermal growth factor receptor (EGFR) mRNA from multiple non-mutated cancer cells by combining single-cell microarray chips and peptide nucleic acid (PNA)-DNA probes. The single-cell microarray chip is made of polystyrene with 62,410 microchambers (31-40 µm diameter). The T790M-mutated lung cancer cell line, NCI-H1975, and non-mutated lung cancer cell line, A549, were successfully separated into single cells in each microchambers on the chip. Only NCI-H1975 cell was stained on the chip with a fluorescein isothiocyanate (FITC)-conjugated PNA probe for specifically detecting T790M mutation. Of the NCI-H1975 cells that spiked into A549 cells, 0-20% were quantitatively analyzed within 1 h, depending on the spike concentration. Therefore, our system could be useful in analyzing cancer tissue that contains a few anticancer drug-resistant cells.

Potentiometric responses of ion-selective microelectrode with bovine serum albumin adsorption.

There is a growing demand for an in situ measurement of local pH and ion concentrations in biological milieu to monitor ongoing process of bioreaction and bioresponse in real time. An ion-selective microelectrode can meet the requirements. However, the contact of the electrode with biological fluids induces biofouling by protein adsorption to result in a noise signal. Therefore, we investigated the relationship between the amount of nonspecific protein adsorption and the electrical signals in potentiometry by using ion-selective microelectrodes, namely silver/silver chloride (Ag/AgCl), iridium/iridium oxides (Ir/IrOx), and platinum/iridium oxides (Pt/IrOx). The microelectrodes reduced a potential change following the adsorption of bovine serum albumin (BSA) by comparison with the original metal microelectrodes without oxide layers. Suppression in the noise signal was attributed to the increased capacitance at the electrode/solution interface due to the formation of granulated metal oxide layer rather than a decrease in the amount of protein adsorbed. Ion sensitivity was maintained for Ir/IrOx against proton, but it was not for Ag/AgCl against chloride ion (Cl(-)), because of the interference of the equilibrium reaction by adsorbed BSA molecules on the electrode surface at<10(-2)M [Cl(-)] in the solution. The results open up the application of the Ir/IrOx microelectrode for measuring local pH in realistic dirty samples with a limited influence of electrode pollution by protein adsorption.

Low haemoglobin levels contribute to low grip strength independent of low-grade inflammation in Japanese elderly women.

Muscle strength declines with age. However, factors that contribute to such declines are not well documented and have not been extensively studied in elderly populations of Asian origin. Correlations of grip strength with a broad range of factors associated with declines in muscle strength were examined in 202 community-living elderly Japanese women. After adjustment for age, grip strength was positively correlated with body weight, height, serum albumin, haemoglobin, high-density lipoprotein cholesterol (HDL-C) and serum iron and inversely with serum copper, and log high-sensitivity C-reactive protein (hsCRP). Multiple linear regression analysis with grip strength as a dependent variable showed that 47.0% of variability of grip strength could be accounted for by height, age and haemoglobin in order of increasing R2. In conclusion, low haemoglobin may contribute to low muscle strength independently of age, anthropometric, nutritional, and inflammatory markers in the elderly, and may represent an important confounder of the association between grip strength and functional decline in community- living Japanese elderly women.

Association of pulse pressure with serum TNF-α and neutrophil count in the elderly.

AIMS: Elevated pulse pressure (PP) has been reported to be a risk factor for type 2 diabetes in elderly patients with hypertension. METHODS: Cross-sectional relationships of PP with known risk factors for type 2 diabetes and inflammatory markers were examined in 150 elderly community-dwelling women, 79 women (52.7%) of whom had hypertension. RESULTS: Systolic blood pressure (standardized ß, 0.775), log tumor necrosis factor-α (TNF-α, standardized ß, 0.110), age (standardized ß, 0.140), and neutrophil count (standardized ß, 0.114) emerged as determinants of PP independent of high-sensitivity C-reactive protein, interleukin-6, monocyte count, plasminogen activator inhibitor-1, homeostasis model assessment of insulin resistance, HDL-cholesterol, and adiponectin (R(2) = 0.772). CONCLUSIONS: The present studies have demonstrated an independent association of higher PP with higher TNF-α, a marker of insulin resistance, and neutrophil count in community-living elderly women and suggest that insulin resistance and chronic low-grade inflammation may in part be responsible for the association between high PP and incident type 2 diabetes found in elderly patients with hypertension.

Contrast agent Gd-EOB-DTPA (EOB·Primovist®) for low-field magnetic resonance imaging of canine focal liver lesions.

Contrast-enhanced magnetic resonance (MR) imaging with a new liver-specific contrast agent gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA; EOB·Primovist®) was studied in 14 normal beagles and 9 dogs with focal liver lesions. Gd-EOB-DTPA accumulates in normally functioning hepatocytes 20 min after injection. As with Gd-DTPA, it is also possible to perform a dynamic multiphasic examination of the liver with Gd-EOB-DTPA, including an arterial phase and a portal venous phase. First, a reliable protocol was developed and the appropriate timings for the dynamic study and the parenchymal phase in normal dogs using Gd-EOB-DTPA were determined. Second, the patterns of these images were evaluated in patient dogs with hepatic masses. The optimal time of arterial imaging was from 15 s after injection, and the optimal time for portal venous imaging was from 40 s after injection. Meanwhile, the optimal time to observe changes during the hepatobiliary phase was from 20 min after injection. In patient dogs, 11 lesions were diagnosed as malignant tumors; all were hypointense to the surrounding normal liver parenchyma during the hepatobiliary phase. Even with a low-field MR imaging unit, the sequences afforded images adequate to visualize the liver parenchyma and to detect tumors within an appropriate scan time. Contrast-enhanced MR imaging with Gd-EOB-DTPA provides good demarcation on low-field MR imaging for diagnosing canine focal liver lesions.

Paired receptor systems of the innate immune system.

This appendix describes paired receptors involved in the innate immune system. "Paired Receptors" are defined as families of related membrane proteins that show the following characteristics: (1) they are encoded by different genes, but located as a gene cluster on a given chromosome; (2) they have significant homology within their extracellular domains; (3) they are expressed on overlapping immune populations; and (4) they are confirmed to have both activating and inhibitory members. For simplicity in nomenclature, the authors used the official gene nomenclature provided by NCBI and listed all other names in the alias field. Paired receptor information related to both mouse and human systems is included, as some families exist in both species whereas others are important in the study of either human or murine models of disease.

Novel KIR3DL1 alleles and their expression levels on NK cells: convergent evolution of KIR3DL1 phenotype variation?

KIR3DL1 shows extensive polymorphism, and its variation has functional significance in terms of cell-surface expression levels and inhibitory capacity. We characterized nine KIR3DL1 alleles (*022, *028, *029, *033, *035, *051, *052, *053, and *054), four of which were identified for the first time in this study, and compared them to known alleles in phylogenetic analysis. Blood was available from eight individuals with these alleles, and cell-surface expression on NK cells could be determined for six of them using the KIR3DL1-specific Ab DX9. Four of the alleles were expressed at clearly detectable levels, and two others showed exceptionally low levels of expression. Site-directed mutagenesis demonstrated that single amino acid changes can result in either diminished or enhanced DX9 staining compared with the respective related KIR3DL1 allotypes. These results raise the possibility that KIR3DL1 evolution maintains variation in KIR3DL1 cell-surface expression levels, potentially due to the effect of such variation on functional capacity.

Alterations in receptor binding properties of recent human influenza H3N2 viruses are associated with reduced natural killer cell lysis of infected cells.

Natural killer (NK) cell recognition of influenza virus-infected cells involves hemagglutinin (HA) binding to sialic acid (SA) on activating NK receptors. SA also acts as a receptor for the binding of influenza virus to its target host cells. The SA binding properties of H3N2 influenza viruses have been observed to change during circulation in humans: recent isolates are unable to agglutinate chicken red blood cells and show reduced affinity for synthetic glycopolymers representing SA-alpha-2,3-lactose (3'SL-PAA) and SA-alpha-2,6-N-acetyl lactosamine (6'SLN-PAA) carbohydrates. Here, NK lysis of cells infected with human H3N2 influenza viruses isolated between 1969 and 2003 was analyzed. Cells infected with recent isolates (1999 to 2003) were found to be lysed less effectively than cells infected with older isolates (1969 to 1996). This change occurred concurrently with the acquisition of two new potential glycosylation site motifs in HA. Deletion of the potential glycosylation site motif at 133 to 135 in HA1 from a recent isolate partially restored the agglutination phenotype to a recombinant virus, indicating that the HA-SA interaction is inhibited by the glycosylation modification. Deletion of either of the recently acquired potential glycosylation sites from HA led to increased NK lysis of cells infected with recombinant viruses carrying modified HA. These results indicate that alterations in HA glycosylation may affect NK cell recognition of influenza virus-infected cells in addition to virus binding to host cells.

Detection of KIR3DS1 on the cell surface of peripheral blood NK cells facilitates identification of a novel null allele and assessment of KIR3DS1 expression during HIV-1 infection.

KIR3DL1 is a highly polymorphic killer cell Ig-like receptor gene with at least 23 alleles described, including its activating counterpart, KIR3DS1. Recently, the KIR3DS1 allele has been shown to slow progression to AIDS in individuals expressing HLA-Bw4 with isoleucine at position 80. However, due to the lack of a specific Ab, KIR3DS1 expression and function is not well characterized. In this study, we demonstrate KIR3DS1 expression on a substantial subset of peripheral natural killer cells through its recognition by the mAb Z27. The fidelity of this detection method was confirmed by analysis of KIR3DS1 transfectants and the identification of a novel KIR3DS1 null allele. Interestingly, KIR3DS1 is also expressed by a small proportion of CD56(+) T cells. We show that ligation of KIR3DS1 by Z27 leads to NK cell IFN-gamma production and degranulation as assessed by expression of CD107a. Furthermore, we document the persistence of KIR3DS1(+) NK cells in HIV-1 viremic patients. The high frequency of KIR3DS1 expression, along with its ability to activate NK cells, and its maintenance during HIV-1 viremia are consistent with the epidemiological data suggesting a critical role for this receptor in controlling HIV-1 pathogenesis.

Analysis of the binding of hepatitis C virus genotype 1a and 1b E2 glycoproteins to peripheral blood mononuclear cell subsets.

Hepatitis C virus (HCV) binding to hepatocytes is thought to be mediated via interaction of the E2 glycoprotein with (co-)receptors including CD81 and scavenger receptor class B type I (SR-BI). Here, the expression of CD81 and SR-BI was analysed on peripheral blood mononuclear cell (PBMC) subsets, and the binding of genotype 1 soluble truncated E2 (sE2) proteins to these cells was investigated. All PBMC subsets expressed CD81, although at varying levels. In contrast, SR-BI was only detected on monocytes and dendritic cells (DCs). The genotype 1a H77c sE2 protein showed higher PBMC binding than other genotype 1a/b sE2s. H77c sE2 binding to different PBMC subsets largely paralleled their level of CD81 expression, and could be inhibited by blocking E2-CD81 interaction. However, those PBMC subsets reported to be infected by HCV in vivo (monocytes, DCs and B cells) also exhibited residual, CD81-independent binding, indicating roles for SR-BI/other receptor(s) in mediating haematopoietic cell infection.

Synthesis and biological activity of novel alpha-substituted beta-phenylpropionic acids having pyridin-2-ylphenyl moiety as antihyperglycemic agents.

We previously reported the identification of novel oximes having 5-benzyl-2,4-thiazolidinedione with antihyperglycemic activity. We now report the synthesis and biological activity of a novel series of oximes and amides having alpha-substituted-beta-phenylpropionic acids. In this series, we obtained potent PPAR alpha/gamma dual agonist (S)-9d, with which activation of PPAR alpha and PPAR gamma was considerably more potent than that of the reference compounds GW9578 22 and rosiglitazone 3, respectively. This means (S)-9d is of the strongest class of PPAR alpha/gamma dual agonists. In the course of this study, we also obtained 8h, which indicated potent plasma glucose lowering effect in spite of weak PPAR alpha/gamma agonistic activity.