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Background. The live attenuated vaccine Zostavax was developed to prevent varicella zoster virus (VZV) reactivation that causes herpes zoster (shingles) in older humans. However, the impact of vaccination on the cutaneous response to VZV is not known. Methods. We investigated the response to intradermal VZV antigen challenge before and after Zostavax vaccination in participants >70 years of age by immunohistological and transcriptomic analyses of skin biopsy specimens collected from the challenge site. Results. Vaccination increased the proportion of VZV-specific CD4(+) T cells in the blood and promoted the accumulation of both CD4(+) and CD8(+) T cells in the skin after VZV antigen challenge. However, Zostavax did not alter the proportion of resident memory T cells (CD4(+) and CD8(+)) or CD4(+) Foxp3(+) regulatory T cells in unchallenged skin. After vaccination, there was increased cutaneous T-cell proliferation at the challenge site and also increased recruitment of T cells from the blood, as indicated by an elevated T-cell migratory gene signature. CD8(+) T-cell-associated functional genes were also highly induced in the skin after vaccination. Conclusion. Zostavax vaccination does not alter the abundance of cutaneous resident memory T cells but instead increases the recruitment of VZV-specific T cells from the blood and enhances T-cell activation, particularly cells of the CD8(+) subset, in the skin after VZV antigen challenge.

Stem cells regenerate tissues in homeostasis and under stress. By taking cues from their microenvironment or "niche,'' they smoothly transition between these states. Immune cells have surfaced as prominent members of stem cell niches across the body. Here, we draw parallels between different stem cell niches to explore the context-specific interactions that stem cells have with tissue-resident and recruited immune cells. We also highlight stem cells' innate ability to sense and respond to stress and the enduring memory that forms from such encounters. This fascinating crosstalk holds great promise for novel therapies in inflammatory diseases and regenerative medicine.

The massive expansions of odorant receptor (OR) genes in ant genomes are notable examples of rapid genome evolution and adaptive gene duplication. However, the molecular mechanisms leading to gene family expansion remain poorly understood, partly because available ant genomes are fragmentary. Here, we present a highly contiguous, chromosome-level assembly of the clonal raider ant genome, revealing the largest known OR repertoire in an insect. While most ant ORs originate via local tandem duplication, we also observe several cases of dispersed duplication followed by tandem duplication in the most rapidly evolving OR clades. We found that areas of unusually high transposable element density (TE islands) were depauperate in ORs in the clonal raider ant, and found no evidence for retrotransposition of ORs. However, OR loci were enriched for transposons relative to the genome as a whole, potentially facilitating tandem duplication by unequal crossing over. We also found that ant OR genes are highly AT-rich compared to other genes. In contrast, in flies, OR genes are dispersed and largely isolated within the genome, and we find that fly ORs are not AT-rich. The genomic architecture and composition of ant ORs thus show convergence with the unrelated vertebrate ORs rather than the related fly ORs. This might be related to the greater gene numbers and/or potential similarities in gene regulation between ants and vertebrates as compared to flies.

Prescription opioid abuse, for example of oxycodone, is a pressing public health issue. This study focuses on how chronic oxycodone self-administration (SA) affects the reward pathways in the mouse brain. In this study, we tested the hypothesis that the expression of reward-related genes in the ventral and dorsal striatum, areas involved in different aspects of opioid addiction models, was altered within 1 h after chronic oxycodone SA, using transcriptome-wide sequencing (RNA-seq). Based on results from earlier human genetic and rodent preclinical studies, we focused on a set of genes that may be associated with the development of addictive diseases and the rewarding effect of drugs of abuse, primarily in the opioid, stress response and classical neurotransmitter systems. We found that 32 transcripts in the ventral striatum, and 7 in the dorsal striatum, were altered significantly in adult mice that had self-administered oxycodone (n = 5) for 14 consecutive days (4 hiday) compared with yoked saline controls (n = 5). The following 5 genes in the ventral striatum showed experiment-wise significant changes: proopiomelanocortin (Pomc) and serotonin 5-HT-2A receptor (Htr2a) were upregulated; serotonin receptor 7 (Htr7), galanin receptor1 (Galr1) and glycine receptor 1 (Glra1) were downregulated. Some genes detected by RNA-seq were confirmed by quantitative polymerase chain reaction (qPCR). Conclusion: A RNA-seq study shows that chronic oxycodone SA alters the expression of several reward-related genes in the dorsal and ventral striatum. These results suggest potential mechanisms underlying neuronal adaptation to chronic oxycodone self-exposure, of relevance to our mechanistic understanding of prescription opioid abuse. (C) 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

The N-glycans attached to the Fab and Fc domains play distinct roles in modulating the functions of antibodies. However, post-translational site-selective modifications of glycans in antibodies and other multiply glycosylated proteins remain a challenging task. Here, we report a chemoenzymatic method that permits independent manipulation of the Fab and Fc N-glycans, using cetuximab as a model therapeutic monoclonal antibody. Taking advantage of the substrate specificity of three endoglycosidases (Endo-S, Endo-S2, and Endo-F3) and their glycosynthase mutants, together with an unexpected substrate site-selectivity of a bacterial alpha 1,6-fucosidase from Lactobacillus casei (AlfC), we were able to synthesize an optimal homogeneous glycoform of cetuximab in which the heterogeneous and immunogenic Fab N-glycans were replaced with a single sialylated N-glycan, and the core-fucosylated Fc N-glycans were remodeled with a nonfucosylated and fully galactosylated N-glycan. The glycoengineered cetuximab demonstrated increased affinity for the Fc gamma IIIa receptor and significantly enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) activity.

Mature microRNAs (miRNAs) are a class of small noncoding RNA molecules involved in regulation of post-translational gene expression. Although aberrant levels of miRNAs have been found in various tumor tissues, their importance in tumor development and the molecular basis of their regulatory role remain unclear. Our bioinformatic analysis on The Cancer Genome Atlas database and microarray-based comparison of miRNA in different cell lines revealed that the level of mir-1287 is suppressed in hepatocellular carcinoma (HCC) cells. When upregulated, mir-1287 can reduce the tumorigenesis phenotypes of HCC cells in several in vitro models. We further found that mir-1287 directly targets messenger RNA encoding PIK3R3, which is a tumor-promoting factor acting in several pathways linked to tumorigenesis. Our study suggests that aberrant suppression of mir-1287 is potentially responsible for the development of HCC, and miRNA-based strategies may be developed for efficient detection and treatment of HCC.

Background: The prevalence of nosocomial meticillin-resistant Staphylococcus aureus (MRSA) was previously estimated as 23% in a paediatric hospital in Luanda, Angola and 18% in a general hospital in Sao Tome and Principe. Aim: To evaluate the prevalence of S. aureus/MRSA colonization among hospitalized children and their parents at two hospitals in Angola and Sao Tome and Principe. Methods: In 2017, 127 hospitalized children and 129 of their parents had nasal swabs for S. aureus/MRSA carriage in the two countries. The isolates were tested for the presence of the mecA and Panton-Valentine leukocidin (PVL) genes, and characterized by pulsed-field gel electrophoresis (PFGE), spa typing, multi-locus sequence typing and SCCmec typing. Findings: Twenty of 127 children (15.7%) and 13 of 129 parents (10.1%) were MRSA nasal carriers. Three lineages comprised 88% of the MRSA isolates: (i) PFGE A-ST5-SCCmec IVa (N=15; 45%), associated with spa type t105, recovered in Angola alone; (ii) PFGE N-ST8-IV/ V (N=7; 21%), associated with spa types t008/t121, recovered in Sao Tome and Principe alone; and (iii) PFGE B-ST88-IVa (N=7; 21%), associated with spa types t325/t786, present in both countries. Fifteen child/guardian pairs were colonized with identical MRSA (N=8) or meticillin-susceptible S. aureus (N=7) strains. PVL was detected in 25% of isolates, including two MRSA (ST30-V and ST8-IVa). Conclusion: Hospitalized children and their parents are important reservoirs of MRSA. Infection control measures should focus on parents in order to minimize the spread of MRSA to the community. (C) 2018 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Lead exposure is an unresolved pediatric health risk and disproportionately affects children in lower-income neighborhoods. Residences with children younger than age 5 years are the focus of mitigation policies; however, studies have shown that older children between the ages of 5 and 12 years also are at risk of central nervous system effects. Whether historically contaminated neighborhoods present ongoing risk to older children also is of concern. This study compared the blood lead levels (BLLs) of older children from an historically contaminated urban neighborhood to those of demographically matched children from a nearby rural locale and predicted significantly higher BLLs in the urban children. The study included 222 children aged 5-12 years, 111 from the urban neighborhood and 111 from local rural townships, matched for age, sex, race/ethnicity, and family income. Blood lead, cadmium, and mercury were measured using inductively coupled plasma mass spectrometry. General linear models tested whether geographic location (urban vs. rural) predicted child heavy metal levels, controlling for sex and age. Only location predicted only child BLL (R-2=0.36); children living in the urban setting had significantly higher BLLs as compared with matched rural township children (F=125, df(220,2), p<0.001). Neighborhoods with a history of lead contamination can present current risk of lead exposure for older children between the ages of 5 and 12 years, as well as for infants and toddlers. More studies are needed to better characterize the risk of lead exposure to older children, particularly in lower-income neighborhoods with a history of lead contamination.